Cutis

Eyelid dermatitis is a common dermatologic concern representing a broad group of inflammatory dermatoses and typically presenting as eczematous lesions on the eyelids.¹ One of the most common causes of eyelid dermatitis is thought to be allergic contact dermatitis (ACD), a type IV delayed hypersensitivity reaction caused by exposure to external allergens.² Although ACD can occur anywhere on the body, dermatitis on the face and eyelids is quite common.^1,2 This article aims to explore the clinical manifestation, evaluation, and management of eyelid ACD.

Pathophysiology of Eyelid ACD

Studies have shown that ACD is the most common cause of eyelid dermatitis, estimated to account for 46% to 72% of cases worldwide.^3-6 Allergic contact dermatitis is a T cell–mediated type IV hypersensitivity reaction to external antigens that manifests as eczematous lesions at the site of contact with the allergen that may spread.⁷ Allergic contact dermatitis is a common condition, and it is estimated that at least 20% of the general worldwide population has a contact allergy.^8,9 Histologically, ACD manifests as spongiotic dermatitis, though this is not unique and also may be seen in atopic dermatitis (AD) and irritant contact dermatitis.² Allergic contact dermatitis is diagnosed via epicutaneous patch testing, and treatment involves allergen avoidance with or without adjuvant topical and/or systemic immunomodulatory treatments.⁷

The eyelids are uniquely prone to the development of ACD given their thinner epidermis and increased susceptibility to irritation. They frequently are exposed to allergens through the direct topical route as well as indirectly via airborne exposure, rinse-down products (eg, shampoos), and substances transferred from an individual’s own hands. The occluded skin folds of the eyelids facilitate increased exposure to trapped allergens.^10,11 Additionally, the skin of the eyelids is thin, flexible, highly vascularized, and lacking in subcutaneous tissue, making this area more susceptible to antigen penetration than other locations on the body.^1,2,10,12,13

Clinical Manifestations

Eyelid ACD is more common in females than males, which is thought to be related to increased use of cosmetics and fragrances.^1,3,12,14-16 Clinical manifestations may resemble eczematous papules and plaques.¹ Eyelid ACD commonly spreads beyond the eyelid margin, which helps to differentiate it from AD and irritant contact dermatitis. Symptoms of ACD on the eyelids typically include pruritus, redness, swelling, tearing, scaling, and pain.² Persistent untreated eyelid dermatitis can lead to eyelash loss, damage to meibomian glands, and hyperpigmentation.^2,17,18

Patterns of Eyelid ACD

Allergic contact dermatitis on the eyelids can occur due to direct application of allergens onto the skin of the eyelids, runoff of products from the hair/scalp (eg, shampoo), transfer of allergens from the hands, or contact with airborne allergens.^1,2,11,12 Some reports have suggested that eyelid ACD more often is caused by products applied to the scalp or face rather than those applied directly to the eyelids.¹¹ Because the scalp and face are less reactive to contact allergens, in some cases the eyelids may be the only affected site.^10,12,13

The specific pattern of dermatitis on or around the eyelids can provide clues to the allergenic source. Dermatitis present around the eyelids and periorbital region with involvement of the bilateral upper and lower eyelids suggests direct exposure to a contact allergen, such as makeup or other cosmetic products.¹ Unilateral involvement of only 1 eyelid can occur with ectopic transfer of allergens from the hands or nails.^1,19 Involvement of the fingers or nails in addition to the eyelids may further suggest ectopic transfer, such as from allergens in nail polish.¹⁰ Unilateral eyelid dermatitis also could be caused by unique exposures such as a microscope or camera eyepiece.¹⁹ Distribution around the lower eyelids and upper cheeks is indicative of a drip or runoff pattern, which may result from an ophthalmic solution such as eye drops or contact lens solution.^1,19 Finally, dermatitis affecting the upper eyelids along with the nasolabial folds and upper chest may suggest airborne contact dermatitis to fragrances or household cleaning products.^1,11

Common Culprits of Eyelid ACD

Common causes of eyelid ACD include cosmetic products, ophthalmic medications, nail lacquers, and jewelry.^10,13,20 Within the broader category of cosmetics, allergens may be found in makeup and makeup removers, cosmetic applicators and brushes, soaps and cleansers, creams and sunscreens, antiaging products, hair products, nail polish and files, and hair removal products, among many others.^10,13,16,20 Additionally, ophthalmologic and topical medications are common sources of ACD, including eyedrops, contact lens solution, and topical antibiotics.^10,13,21 Costume jewelry commonly contains allergenic metals, which also can be found in eyelash curlers, eyeglasses, toys, and other household items.^22,23 Finally, contact allergens can be found in items such as goggles, gloves, textiles, and a variety of other occupational and household exposures.

Allergic contact dermatitis of the eyelids occurs predominantly—but not exclusively—in females.^16,20,24 This finding has been attributed to the traditionally greater use of cosmetics and fragrances among women; however, the use of skin care products among men is increasing, and recent studies have shown the eyelids to be a common location of facial contact dermatitis among men.^16,24 Although eyelid dermatitis has not been specifically analyzed by sex, a retrospective analysis of 1332 male patients with facial dermatitis found the most common sites to be the face (not otherwise specified)(48.9%), eyelids (23.5%), and lips (12.6%). In this cohort, the most common allergens were surfactants in shampoos and paraphenylenediamine in hair dyes.²⁴

Common Allergens

Common contact allergens among patients with ACD of the eyelids include metals, fragrances, preservatives, acrylates, and topical medications.^{3,10,16,20,25-27} Sources of common contact allergens are reviewed in Table 1.

Metals—Metals are among the most common causes of ACD overall, and nickel frequently is reported as one of the top contact allergens in patients with eyelid dermatitis.^16,27 A retrospective analysis of 2332 patients with eyelid dermatitis patch tested by the North American Contact Dermatitis Group from 1994 to 2016 found that 18.6% of patients with eyelid ACD had a clinically relevant nickel allergy. Sources of nickel exposure include jewelry, grooming devices, makeup and makeup applicators, and eyelash curlers, as well as direct transfer from the hands after contact with consumer products.¹⁶

Other metals that can cause ACD include cobalt (found in similar products to nickel) and gold. Gold often is associated with eyelid dermatitis, though its clinical relevance has been debated, as gold is a relatively inert metal that rarely is present in eye cosmetics and its ions are not displaced from objects and deposited on the skin via sweat in the same way as nickel.^{4,16,20,28-30} Despite this, studies have shown that gold is a common positive patch test reaction among patients with eyelid dermatitis, even in patients with no dermatitis at the site of contact with gold jewelry.^20,29,31 Gold has been reported to be the most common allergen causing unilateral eyelid dermatitis via ectopic transfer.^16,19,20,29 It has been proposed that titanium dioxide, present in many cosmetics and sunscreens, displaces gold allowing its release from jewelry, thereby liberating the fine gold ions and allowing them to desposit on the face and eyelids.^30,31 Given the uncertain clinical relevance of positive patch test reactions to gold, Warshaw at al¹⁶ recommend a 2- to 3-month trial of gold jewelry avoidance to establish relevance, and Ehrlich and Gold²⁹ noted that avoidance of gold leads to improvement.

Fragrances—Fragrances represent a broad category of naturally occurring and man-made components that often are combined to produce a desired scent in personal care products.³² Essential oils and botanicals are both examples of natural fragrances.³³ Fragrances are found in numerous products including makeup, hair products, and household cleaning supplies and represent some of the most common contact allergens.³² Common fragrance allergens include fragrance mixes I and II, hydroperoxides of linalool, and balsam of Peru.^12,32,34 Allergic contact dermatitis to fragrances typically manifests on the eyelids, face, or hands.³³ Several studies have found fragrances to be among the top contact allergens in patients with eyelid dermatitis.^{3,12,20,25,34} Patch testing for fragrance allergy may include baseline series, supplemental fragrance series, and personal care products.^32,35

Preservatives—Preservatives, including formaldehyde and formaldehyde releasers (eg, quaternium-15 and ­bronopol) and methylchloroisothiazolinone/­methylisothiazolinone, may be found in personal care products such as makeup, makeup removers, emollients, shampoos, hair care products, and ophthalmologic solutions and are among the most common cosmetic sources of ACD.^13,36-39 Preservatives are among the top allergens causing eyelid dermatitis.²⁰ In particular, patch test positivity rates to methylchloroisothiazolinone/methylisothiazolinone have been increasing in North America.⁴⁰ Sensitization to preservatives may occur through direct skin contact or transfer from the hands.⁴¹

Acrylates—Acrylates are compounds derived from acrylic acid that may be found in acrylic and gel nails, eyelash extensions, and other adhesives and are frequent causes of eyelid ACD.^4,10,42 Acrylate exposure may be cosmetic among consumers or occupational (eg, aestheticians).^42,43 Acrylates on the nails may cause eyelid dermatitis via ectopic transfer from the hands and also may cause periungual dermatitis manifesting as nail bed erythema.¹⁰ Hydroxyethyl methacrylate is one of the more common eyelid ACD allergens, and studies have shown increasing prevalence of positive reaction rates to hydroxyethylmethacrylate.^10,44Topical Medications—Contact allergies to topical medications are quite common, estimated to occur in 10% to 17% of patients undergoing patch testing.⁴⁵ Both active and inactive ingredients of topical medications may be culprits in eyelid ACD. The most common topical medication allergens include antibiotics, steroids, local anesthetics, and nonsteroidal anti-inflammatory drugs.⁴⁵ Topical antibiotics such as neomycin and bacitracin represent some of the most common causes of eyelid dermatitis^4,10 and may be found in a variety of products, including antibacterial ointments and eye drops.¹ Many ophthalmologic medications also contain corticosteroids, with the most common allergenic steroids being tixocortol pivalate (a marker for hydrocortisone allergy) and budesonide.^10,20 Topical steroids pose a particular dilemma, as they can be either the source of or a treatment for ACD.¹⁰ Eye drops also may contain anesthetics, β-blockers, and antihistamines, as well as the preservative benzalkonium chloride, all of which may be contact allergens.^21,39

Differential Diagnosis of Eyelid Dermatitis

Although ACD is reported to be the most common cause of eyelid dermatitis, the differential diagnosis is broad, including endogenous inflammatory dermatoses and exogenous exposures (Table 2). Symptoms of eyelid ACD can be nonspecific (eg, erythema, pruritus), making diagnosis challenging.⁴⁶

Atopic dermatitis represents another common cause of eyelid dermatitis, accounting for 14% to 39.5% of cases.^3-5,49 Atopic dermatitis of the eyelids classically manifests with lichenification of the medial aspects of the eyelids.⁵⁰ Atopic dermatitis and ACD may be difficult to distinguish, as the 2 conditions appear clinically similar and can develop concomitantly.⁵¹ Additionally, atopic patients are likely to have comorbid allergic rhinitis and sensitivity to environmental allergens, which may lead to chronic eye scratching and lichenification.^1,51 Clinical features of eyelid dermatitis suggesting allergic rhinitis and likely comorbid AD include creases in the lower eyelids (Dennie-Morgan lines) and periorbital hyperpigmentation (known as the allergic shiner) due to venous congestion.^1,52

Seborrheic dermatitis is an inflammatory reaction to Malassezia yeast that occurs in sebaceous areas such as the groin, scalp, eyebrows, eyelids, and nasolabial folds.^1,53,54

Irritant contact dermatitis, a nonspecific inflammatory reaction caused by direct cell damage from external irritants, also may affect the eyelids and appear similar to ACD.¹ It typically manifests with a burning or stinging sensation, as opposed to pruritus, and generally develops and resolves more rapidly than ACD.¹ Personal care products are common causes of eyelid irritant contact dermatitis.¹⁶

Patch Testing for Eyelid ACD

The gold standard for diagnosis of ACD is patch testing, outlined by the International Contact Dermatitis Research Group.^55-57 Patch testing generally is performed with standardized panels of allergens and can be customized either with supplemental panels based on unique exposures or with the patient’s own personal care products to increase the sensitivity of testing. Therefore, a thorough history is crucial to identifying potential allergens in a patient’s environment.

False negatives are possible, as the skin on the back may be thicker and less sensitive than the skin at the location of dermatitis.^2,58 This is particularly relevant when using patch testing to diagnose ACD of the eyelids, where the skin is particularly thin and sensitive.² Additionally, ingredients of ophthalmic medications are known to have an especially high false-negative rate with standard patch testing and may require repeated testing with higher drug concentrations or modified patch testing procedures (eg, open testing, scratch-patch testing).^1,59

Treatment

Management of ACD involves allergen avoidance, typically dictated by patch test results.¹⁰ Allergen avoidance may be facilitated using online resources such as the Contact Allergen Management Program (https://www.acdscamp.org/) created by the American Contact Dermatitis Society.^10,18 Patient counseling following patch testing is crucial to educating patients about sources of potential allergen exposures and strategies for avoidance. In the case of eyelid dermatitis, it is particularly important to consider exposure to airborne allergens such as fragrances.¹⁶ Fragrance avoidance is uniquely difficult, as labelling standards in the United States currently do not require disclosure of specific fragrance components.³³ Additionally, products labelled as unscented may still contain fragrances. As such, some patients with fragrance allergy may need to carefully avoid all products containing fragrances.³³

In addition to allergen avoidance, eyelid ACD may be treated with topical medications (eg, steroids, calcineurin inhibitors, Janus kinase inhibitors); however, these same topical medications also can cause ACD due to some ingredients such as propylene glycol.¹⁰ Topical steroids should be used with caution on the eyelids given the risk for atrophy, cataracts, and glaucoma.¹

Final Interpretation

Eyelid dermatitis is a common dermatologic condition most frequently caused by ACD due to exposure to allergens in cosmetic products, ophthalmic medications, nail lacquers, and jewelry, among many other potential sources. The most common allergens causing eyelid dermatitis include metals (particularly nickel), fragrances, preservatives, acrylates, and topical medications. Eyelid ACD is diagnosed via patch testing, and the mainstay of treatment is strict allergen avoidance. Patient counseling is vital for successful allergen avoidance and resolution of eyelid ACD.

Eyelid dermatitis is a common dermatologic concern representing a broad group of inflammatory dermatoses and typically presenting as eczematous lesions on the eyelids.¹ One of the most common causes of eyelid dermatitis is thought to be allergic contact dermatitis (ACD), a type IV delayed hypersensitivity reaction caused by exposure to external allergens.² Although ACD can occur anywhere on the body, dermatitis on the face and eyelids is quite common.^1,2 This article aims to explore the clinical manifestation, evaluation, and management of eyelid ACD.

Pathophysiology of Eyelid ACD

Studies have shown that ACD is the most common cause of eyelid dermatitis, estimated to account for 46% to 72% of cases worldwide.^3-6 Allergic contact dermatitis is a T cell–mediated type IV hypersensitivity reaction to external antigens that manifests as eczematous lesions at the site of contact with the allergen that may spread.⁷ Allergic contact dermatitis is a common condition, and it is estimated that at least 20% of the general worldwide population has a contact allergy.^8,9 Histologically, ACD manifests as spongiotic dermatitis, though this is not unique and also may be seen in atopic dermatitis (AD) and irritant contact dermatitis.² Allergic contact dermatitis is diagnosed via epicutaneous patch testing, and treatment involves allergen avoidance with or without adjuvant topical and/or systemic immunomodulatory treatments.⁷

The eyelids are uniquely prone to the development of ACD given their thinner epidermis and increased susceptibility to irritation. They frequently are exposed to allergens through the direct topical route as well as indirectly via airborne exposure, rinse-down products (eg, shampoos), and substances transferred from an individual’s own hands. The occluded skin folds of the eyelids facilitate increased exposure to trapped allergens.^10,11 Additionally, the skin of the eyelids is thin, flexible, highly vascularized, and lacking in subcutaneous tissue, making this area more susceptible to antigen penetration than other locations on the body.^1,2,10,12,13

Clinical Manifestations

Eyelid ACD is more common in females than males, which is thought to be related to increased use of cosmetics and fragrances.^1,3,12,14-16 Clinical manifestations may resemble eczematous papules and plaques.¹ Eyelid ACD commonly spreads beyond the eyelid margin, which helps to differentiate it from AD and irritant contact dermatitis. Symptoms of ACD on the eyelids typically include pruritus, redness, swelling, tearing, scaling, and pain.² Persistent untreated eyelid dermatitis can lead to eyelash loss, damage to meibomian glands, and hyperpigmentation.^2,17,18

Patterns of Eyelid ACD

Allergic contact dermatitis on the eyelids can occur due to direct application of allergens onto the skin of the eyelids, runoff of products from the hair/scalp (eg, shampoo), transfer of allergens from the hands, or contact with airborne allergens.^1,2,11,12 Some reports have suggested that eyelid ACD more often is caused by products applied to the scalp or face rather than those applied directly to the eyelids.¹¹ Because the scalp and face are less reactive to contact allergens, in some cases the eyelids may be the only affected site.^10,12,13

The specific pattern of dermatitis on or around the eyelids can provide clues to the allergenic source. Dermatitis present around the eyelids and periorbital region with involvement of the bilateral upper and lower eyelids suggests direct exposure to a contact allergen, such as makeup or other cosmetic products.¹ Unilateral involvement of only 1 eyelid can occur with ectopic transfer of allergens from the hands or nails.^1,19 Involvement of the fingers or nails in addition to the eyelids may further suggest ectopic transfer, such as from allergens in nail polish.¹⁰ Unilateral eyelid dermatitis also could be caused by unique exposures such as a microscope or camera eyepiece.¹⁹ Distribution around the lower eyelids and upper cheeks is indicative of a drip or runoff pattern, which may result from an ophthalmic solution such as eye drops or contact lens solution.^1,19 Finally, dermatitis affecting the upper eyelids along with the nasolabial folds and upper chest may suggest airborne contact dermatitis to fragrances or household cleaning products.^1,11

Common Culprits of Eyelid ACD

Common causes of eyelid ACD include cosmetic products, ophthalmic medications, nail lacquers, and jewelry.^10,13,20 Within the broader category of cosmetics, allergens may be found in makeup and makeup removers, cosmetic applicators and brushes, soaps and cleansers, creams and sunscreens, antiaging products, hair products, nail polish and files, and hair removal products, among many others.^10,13,16,20 Additionally, ophthalmologic and topical medications are common sources of ACD, including eyedrops, contact lens solution, and topical antibiotics.^10,13,21 Costume jewelry commonly contains allergenic metals, which also can be found in eyelash curlers, eyeglasses, toys, and other household items.^22,23 Finally, contact allergens can be found in items such as goggles, gloves, textiles, and a variety of other occupational and household exposures.

Allergic contact dermatitis of the eyelids occurs predominantly—but not exclusively—in females.^16,20,24 This finding has been attributed to the traditionally greater use of cosmetics and fragrances among women; however, the use of skin care products among men is increasing, and recent studies have shown the eyelids to be a common location of facial contact dermatitis among men.^16,24 Although eyelid dermatitis has not been specifically analyzed by sex, a retrospective analysis of 1332 male patients with facial dermatitis found the most common sites to be the face (not otherwise specified)(48.9%), eyelids (23.5%), and lips (12.6%). In this cohort, the most common allergens were surfactants in shampoos and paraphenylenediamine in hair dyes.²⁴

Common Allergens

Common contact allergens among patients with ACD of the eyelids include metals, fragrances, preservatives, acrylates, and topical medications.^{3,10,16,20,25-27} Sources of common contact allergens are reviewed in Table 1.

Metals—Metals are among the most common causes of ACD overall, and nickel frequently is reported as one of the top contact allergens in patients with eyelid dermatitis.^16,27 A retrospective analysis of 2332 patients with eyelid dermatitis patch tested by the North American Contact Dermatitis Group from 1994 to 2016 found that 18.6% of patients with eyelid ACD had a clinically relevant nickel allergy. Sources of nickel exposure include jewelry, grooming devices, makeup and makeup applicators, and eyelash curlers, as well as direct transfer from the hands after contact with consumer products.¹⁶

Other metals that can cause ACD include cobalt (found in similar products to nickel) and gold. Gold often is associated with eyelid dermatitis, though its clinical relevance has been debated, as gold is a relatively inert metal that rarely is present in eye cosmetics and its ions are not displaced from objects and deposited on the skin via sweat in the same way as nickel.^{4,16,20,28-30} Despite this, studies have shown that gold is a common positive patch test reaction among patients with eyelid dermatitis, even in patients with no dermatitis at the site of contact with gold jewelry.^20,29,31 Gold has been reported to be the most common allergen causing unilateral eyelid dermatitis via ectopic transfer.^16,19,20,29 It has been proposed that titanium dioxide, present in many cosmetics and sunscreens, displaces gold allowing its release from jewelry, thereby liberating the fine gold ions and allowing them to desposit on the face and eyelids.^30,31 Given the uncertain clinical relevance of positive patch test reactions to gold, Warshaw at al¹⁶ recommend a 2- to 3-month trial of gold jewelry avoidance to establish relevance, and Ehrlich and Gold²⁹ noted that avoidance of gold leads to improvement.

Fragrances—Fragrances represent a broad category of naturally occurring and man-made components that often are combined to produce a desired scent in personal care products.³² Essential oils and botanicals are both examples of natural fragrances.³³ Fragrances are found in numerous products including makeup, hair products, and household cleaning supplies and represent some of the most common contact allergens.³² Common fragrance allergens include fragrance mixes I and II, hydroperoxides of linalool, and balsam of Peru.^12,32,34 Allergic contact dermatitis to fragrances typically manifests on the eyelids, face, or hands.³³ Several studies have found fragrances to be among the top contact allergens in patients with eyelid dermatitis.^{3,12,20,25,34} Patch testing for fragrance allergy may include baseline series, supplemental fragrance series, and personal care products.^32,35

Preservatives—Preservatives, including formaldehyde and formaldehyde releasers (eg, quaternium-15 and ­bronopol) and methylchloroisothiazolinone/­methylisothiazolinone, may be found in personal care products such as makeup, makeup removers, emollients, shampoos, hair care products, and ophthalmologic solutions and are among the most common cosmetic sources of ACD.^13,36-39 Preservatives are among the top allergens causing eyelid dermatitis.²⁰ In particular, patch test positivity rates to methylchloroisothiazolinone/methylisothiazolinone have been increasing in North America.⁴⁰ Sensitization to preservatives may occur through direct skin contact or transfer from the hands.⁴¹

Acrylates—Acrylates are compounds derived from acrylic acid that may be found in acrylic and gel nails, eyelash extensions, and other adhesives and are frequent causes of eyelid ACD.^4,10,42 Acrylate exposure may be cosmetic among consumers or occupational (eg, aestheticians).^42,43 Acrylates on the nails may cause eyelid dermatitis via ectopic transfer from the hands and also may cause periungual dermatitis manifesting as nail bed erythema.¹⁰ Hydroxyethyl methacrylate is one of the more common eyelid ACD allergens, and studies have shown increasing prevalence of positive reaction rates to hydroxyethylmethacrylate.^10,44Topical Medications—Contact allergies to topical medications are quite common, estimated to occur in 10% to 17% of patients undergoing patch testing.⁴⁵ Both active and inactive ingredients of topical medications may be culprits in eyelid ACD. The most common topical medication allergens include antibiotics, steroids, local anesthetics, and nonsteroidal anti-inflammatory drugs.⁴⁵ Topical antibiotics such as neomycin and bacitracin represent some of the most common causes of eyelid dermatitis^4,10 and may be found in a variety of products, including antibacterial ointments and eye drops.¹ Many ophthalmologic medications also contain corticosteroids, with the most common allergenic steroids being tixocortol pivalate (a marker for hydrocortisone allergy) and budesonide.^10,20 Topical steroids pose a particular dilemma, as they can be either the source of or a treatment for ACD.¹⁰ Eye drops also may contain anesthetics, β-blockers, and antihistamines, as well as the preservative benzalkonium chloride, all of which may be contact allergens.^21,39

Differential Diagnosis of Eyelid Dermatitis

Although ACD is reported to be the most common cause of eyelid dermatitis, the differential diagnosis is broad, including endogenous inflammatory dermatoses and exogenous exposures (Table 2). Symptoms of eyelid ACD can be nonspecific (eg, erythema, pruritus), making diagnosis challenging.⁴⁶

Atopic dermatitis represents another common cause of eyelid dermatitis, accounting for 14% to 39.5% of cases.^3-5,49 Atopic dermatitis of the eyelids classically manifests with lichenification of the medial aspects of the eyelids.⁵⁰ Atopic dermatitis and ACD may be difficult to distinguish, as the 2 conditions appear clinically similar and can develop concomitantly.⁵¹ Additionally, atopic patients are likely to have comorbid allergic rhinitis and sensitivity to environmental allergens, which may lead to chronic eye scratching and lichenification.^1,51 Clinical features of eyelid dermatitis suggesting allergic rhinitis and likely comorbid AD include creases in the lower eyelids (Dennie-Morgan lines) and periorbital hyperpigmentation (known as the allergic shiner) due to venous congestion.^1,52

Seborrheic dermatitis is an inflammatory reaction to Malassezia yeast that occurs in sebaceous areas such as the groin, scalp, eyebrows, eyelids, and nasolabial folds.^1,53,54

Irritant contact dermatitis, a nonspecific inflammatory reaction caused by direct cell damage from external irritants, also may affect the eyelids and appear similar to ACD.¹ It typically manifests with a burning or stinging sensation, as opposed to pruritus, and generally develops and resolves more rapidly than ACD.¹ Personal care products are common causes of eyelid irritant contact dermatitis.¹⁶

Patch Testing for Eyelid ACD

The gold standard for diagnosis of ACD is patch testing, outlined by the International Contact Dermatitis Research Group.^55-57 Patch testing generally is performed with standardized panels of allergens and can be customized either with supplemental panels based on unique exposures or with the patient’s own personal care products to increase the sensitivity of testing. Therefore, a thorough history is crucial to identifying potential allergens in a patient’s environment.

False negatives are possible, as the skin on the back may be thicker and less sensitive than the skin at the location of dermatitis.^2,58 This is particularly relevant when using patch testing to diagnose ACD of the eyelids, where the skin is particularly thin and sensitive.² Additionally, ingredients of ophthalmic medications are known to have an especially high false-negative rate with standard patch testing and may require repeated testing with higher drug concentrations or modified patch testing procedures (eg, open testing, scratch-patch testing).^1,59

Treatment

Management of ACD involves allergen avoidance, typically dictated by patch test results.¹⁰ Allergen avoidance may be facilitated using online resources such as the Contact Allergen Management Program (https://www.acdscamp.org/) created by the American Contact Dermatitis Society.^10,18 Patient counseling following patch testing is crucial to educating patients about sources of potential allergen exposures and strategies for avoidance. In the case of eyelid dermatitis, it is particularly important to consider exposure to airborne allergens such as fragrances.¹⁶ Fragrance avoidance is uniquely difficult, as labelling standards in the United States currently do not require disclosure of specific fragrance components.³³ Additionally, products labelled as unscented may still contain fragrances. As such, some patients with fragrance allergy may need to carefully avoid all products containing fragrances.³³

In addition to allergen avoidance, eyelid ACD may be treated with topical medications (eg, steroids, calcineurin inhibitors, Janus kinase inhibitors); however, these same topical medications also can cause ACD due to some ingredients such as propylene glycol.¹⁰ Topical steroids should be used with caution on the eyelids given the risk for atrophy, cataracts, and glaucoma.¹

Final Interpretation

Eyelid dermatitis is a common dermatologic condition most frequently caused by ACD due to exposure to allergens in cosmetic products, ophthalmic medications, nail lacquers, and jewelry, among many other potential sources. The most common allergens causing eyelid dermatitis include metals (particularly nickel), fragrances, preservatives, acrylates, and topical medications. Eyelid ACD is diagnosed via patch testing, and the mainstay of treatment is strict allergen avoidance. Patient counseling is vital for successful allergen avoidance and resolution of eyelid ACD.

Eyelid dermatitis is a common dermatologic concern representing a broad group of inflammatory dermatoses and typically presenting as eczematous lesions on the eyelids.¹ One of the most common causes of eyelid dermatitis is thought to be allergic contact dermatitis (ACD), a type IV delayed hypersensitivity reaction caused by exposure to external allergens.² Although ACD can occur anywhere on the body, dermatitis on the face and eyelids is quite common.^1,2 This article aims to explore the clinical manifestation, evaluation, and management of eyelid ACD.

Pathophysiology of Eyelid ACD

Studies have shown that ACD is the most common cause of eyelid dermatitis, estimated to account for 46% to 72% of cases worldwide.^3-6 Allergic contact dermatitis is a T cell–mediated type IV hypersensitivity reaction to external antigens that manifests as eczematous lesions at the site of contact with the allergen that may spread.⁷ Allergic contact dermatitis is a common condition, and it is estimated that at least 20% of the general worldwide population has a contact allergy.^8,9 Histologically, ACD manifests as spongiotic dermatitis, though this is not unique and also may be seen in atopic dermatitis (AD) and irritant contact dermatitis.² Allergic contact dermatitis is diagnosed via epicutaneous patch testing, and treatment involves allergen avoidance with or without adjuvant topical and/or systemic immunomodulatory treatments.⁷

The eyelids are uniquely prone to the development of ACD given their thinner epidermis and increased susceptibility to irritation. They frequently are exposed to allergens through the direct topical route as well as indirectly via airborne exposure, rinse-down products (eg, shampoos), and substances transferred from an individual’s own hands. The occluded skin folds of the eyelids facilitate increased exposure to trapped allergens.^10,11 Additionally, the skin of the eyelids is thin, flexible, highly vascularized, and lacking in subcutaneous tissue, making this area more susceptible to antigen penetration than other locations on the body.^1,2,10,12,13

Clinical Manifestations

Eyelid ACD is more common in females than males, which is thought to be related to increased use of cosmetics and fragrances.^1,3,12,14-16 Clinical manifestations may resemble eczematous papules and plaques.¹ Eyelid ACD commonly spreads beyond the eyelid margin, which helps to differentiate it from AD and irritant contact dermatitis. Symptoms of ACD on the eyelids typically include pruritus, redness, swelling, tearing, scaling, and pain.² Persistent untreated eyelid dermatitis can lead to eyelash loss, damage to meibomian glands, and hyperpigmentation.^2,17,18

Patterns of Eyelid ACD

Allergic contact dermatitis on the eyelids can occur due to direct application of allergens onto the skin of the eyelids, runoff of products from the hair/scalp (eg, shampoo), transfer of allergens from the hands, or contact with airborne allergens.^1,2,11,12 Some reports have suggested that eyelid ACD more often is caused by products applied to the scalp or face rather than those applied directly to the eyelids.¹¹ Because the scalp and face are less reactive to contact allergens, in some cases the eyelids may be the only affected site.^10,12,13

The specific pattern of dermatitis on or around the eyelids can provide clues to the allergenic source. Dermatitis present around the eyelids and periorbital region with involvement of the bilateral upper and lower eyelids suggests direct exposure to a contact allergen, such as makeup or other cosmetic products.¹ Unilateral involvement of only 1 eyelid can occur with ectopic transfer of allergens from the hands or nails.^1,19 Involvement of the fingers or nails in addition to the eyelids may further suggest ectopic transfer, such as from allergens in nail polish.¹⁰ Unilateral eyelid dermatitis also could be caused by unique exposures such as a microscope or camera eyepiece.¹⁹ Distribution around the lower eyelids and upper cheeks is indicative of a drip or runoff pattern, which may result from an ophthalmic solution such as eye drops or contact lens solution.^1,19 Finally, dermatitis affecting the upper eyelids along with the nasolabial folds and upper chest may suggest airborne contact dermatitis to fragrances or household cleaning products.^1,11

Common Culprits of Eyelid ACD

Common causes of eyelid ACD include cosmetic products, ophthalmic medications, nail lacquers, and jewelry.^10,13,20 Within the broader category of cosmetics, allergens may be found in makeup and makeup removers, cosmetic applicators and brushes, soaps and cleansers, creams and sunscreens, antiaging products, hair products, nail polish and files, and hair removal products, among many others.^10,13,16,20 Additionally, ophthalmologic and topical medications are common sources of ACD, including eyedrops, contact lens solution, and topical antibiotics.^10,13,21 Costume jewelry commonly contains allergenic metals, which also can be found in eyelash curlers, eyeglasses, toys, and other household items.^22,23 Finally, contact allergens can be found in items such as goggles, gloves, textiles, and a variety of other occupational and household exposures.

Allergic contact dermatitis of the eyelids occurs predominantly—but not exclusively—in females.^16,20,24 This finding has been attributed to the traditionally greater use of cosmetics and fragrances among women; however, the use of skin care products among men is increasing, and recent studies have shown the eyelids to be a common location of facial contact dermatitis among men.^16,24 Although eyelid dermatitis has not been specifically analyzed by sex, a retrospective analysis of 1332 male patients with facial dermatitis found the most common sites to be the face (not otherwise specified)(48.9%), eyelids (23.5%), and lips (12.6%). In this cohort, the most common allergens were surfactants in shampoos and paraphenylenediamine in hair dyes.²⁴

Common Allergens

Common contact allergens among patients with ACD of the eyelids include metals, fragrances, preservatives, acrylates, and topical medications.^{3,10,16,20,25-27} Sources of common contact allergens are reviewed in Table 1.

Metals—Metals are among the most common causes of ACD overall, and nickel frequently is reported as one of the top contact allergens in patients with eyelid dermatitis.^16,27 A retrospective analysis of 2332 patients with eyelid dermatitis patch tested by the North American Contact Dermatitis Group from 1994 to 2016 found that 18.6% of patients with eyelid ACD had a clinically relevant nickel allergy. Sources of nickel exposure include jewelry, grooming devices, makeup and makeup applicators, and eyelash curlers, as well as direct transfer from the hands after contact with consumer products.¹⁶

Other metals that can cause ACD include cobalt (found in similar products to nickel) and gold. Gold often is associated with eyelid dermatitis, though its clinical relevance has been debated, as gold is a relatively inert metal that rarely is present in eye cosmetics and its ions are not displaced from objects and deposited on the skin via sweat in the same way as nickel.^{4,16,20,28-30} Despite this, studies have shown that gold is a common positive patch test reaction among patients with eyelid dermatitis, even in patients with no dermatitis at the site of contact with gold jewelry.^20,29,31 Gold has been reported to be the most common allergen causing unilateral eyelid dermatitis via ectopic transfer.^16,19,20,29 It has been proposed that titanium dioxide, present in many cosmetics and sunscreens, displaces gold allowing its release from jewelry, thereby liberating the fine gold ions and allowing them to desposit on the face and eyelids.^30,31 Given the uncertain clinical relevance of positive patch test reactions to gold, Warshaw at al¹⁶ recommend a 2- to 3-month trial of gold jewelry avoidance to establish relevance, and Ehrlich and Gold²⁹ noted that avoidance of gold leads to improvement.

Fragrances—Fragrances represent a broad category of naturally occurring and man-made components that often are combined to produce a desired scent in personal care products.³² Essential oils and botanicals are both examples of natural fragrances.³³ Fragrances are found in numerous products including makeup, hair products, and household cleaning supplies and represent some of the most common contact allergens.³² Common fragrance allergens include fragrance mixes I and II, hydroperoxides of linalool, and balsam of Peru.^12,32,34 Allergic contact dermatitis to fragrances typically manifests on the eyelids, face, or hands.³³ Several studies have found fragrances to be among the top contact allergens in patients with eyelid dermatitis.^{3,12,20,25,34} Patch testing for fragrance allergy may include baseline series, supplemental fragrance series, and personal care products.^32,35

Preservatives—Preservatives, including formaldehyde and formaldehyde releasers (eg, quaternium-15 and ­bronopol) and methylchloroisothiazolinone/­methylisothiazolinone, may be found in personal care products such as makeup, makeup removers, emollients, shampoos, hair care products, and ophthalmologic solutions and are among the most common cosmetic sources of ACD.^13,36-39 Preservatives are among the top allergens causing eyelid dermatitis.²⁰ In particular, patch test positivity rates to methylchloroisothiazolinone/methylisothiazolinone have been increasing in North America.⁴⁰ Sensitization to preservatives may occur through direct skin contact or transfer from the hands.⁴¹

Acrylates—Acrylates are compounds derived from acrylic acid that may be found in acrylic and gel nails, eyelash extensions, and other adhesives and are frequent causes of eyelid ACD.^4,10,42 Acrylate exposure may be cosmetic among consumers or occupational (eg, aestheticians).^42,43 Acrylates on the nails may cause eyelid dermatitis via ectopic transfer from the hands and also may cause periungual dermatitis manifesting as nail bed erythema.¹⁰ Hydroxyethyl methacrylate is one of the more common eyelid ACD allergens, and studies have shown increasing prevalence of positive reaction rates to hydroxyethylmethacrylate.^10,44Topical Medications—Contact allergies to topical medications are quite common, estimated to occur in 10% to 17% of patients undergoing patch testing.⁴⁵ Both active and inactive ingredients of topical medications may be culprits in eyelid ACD. The most common topical medication allergens include antibiotics, steroids, local anesthetics, and nonsteroidal anti-inflammatory drugs.⁴⁵ Topical antibiotics such as neomycin and bacitracin represent some of the most common causes of eyelid dermatitis^4,10 and may be found in a variety of products, including antibacterial ointments and eye drops.¹ Many ophthalmologic medications also contain corticosteroids, with the most common allergenic steroids being tixocortol pivalate (a marker for hydrocortisone allergy) and budesonide.^10,20 Topical steroids pose a particular dilemma, as they can be either the source of or a treatment for ACD.¹⁰ Eye drops also may contain anesthetics, β-blockers, and antihistamines, as well as the preservative benzalkonium chloride, all of which may be contact allergens.^21,39

Differential Diagnosis of Eyelid Dermatitis

Although ACD is reported to be the most common cause of eyelid dermatitis, the differential diagnosis is broad, including endogenous inflammatory dermatoses and exogenous exposures (Table 2). Symptoms of eyelid ACD can be nonspecific (eg, erythema, pruritus), making diagnosis challenging.⁴⁶

Atopic dermatitis represents another common cause of eyelid dermatitis, accounting for 14% to 39.5% of cases.^3-5,49 Atopic dermatitis of the eyelids classically manifests with lichenification of the medial aspects of the eyelids.⁵⁰ Atopic dermatitis and ACD may be difficult to distinguish, as the 2 conditions appear clinically similar and can develop concomitantly.⁵¹ Additionally, atopic patients are likely to have comorbid allergic rhinitis and sensitivity to environmental allergens, which may lead to chronic eye scratching and lichenification.^1,51 Clinical features of eyelid dermatitis suggesting allergic rhinitis and likely comorbid AD include creases in the lower eyelids (Dennie-Morgan lines) and periorbital hyperpigmentation (known as the allergic shiner) due to venous congestion.^1,52

Seborrheic dermatitis is an inflammatory reaction to Malassezia yeast that occurs in sebaceous areas such as the groin, scalp, eyebrows, eyelids, and nasolabial folds.^1,53,54

Irritant contact dermatitis, a nonspecific inflammatory reaction caused by direct cell damage from external irritants, also may affect the eyelids and appear similar to ACD.¹ It typically manifests with a burning or stinging sensation, as opposed to pruritus, and generally develops and resolves more rapidly than ACD.¹ Personal care products are common causes of eyelid irritant contact dermatitis.¹⁶

Patch Testing for Eyelid ACD

The gold standard for diagnosis of ACD is patch testing, outlined by the International Contact Dermatitis Research Group.^55-57 Patch testing generally is performed with standardized panels of allergens and can be customized either with supplemental panels based on unique exposures or with the patient’s own personal care products to increase the sensitivity of testing. Therefore, a thorough history is crucial to identifying potential allergens in a patient’s environment.

False negatives are possible, as the skin on the back may be thicker and less sensitive than the skin at the location of dermatitis.^2,58 This is particularly relevant when using patch testing to diagnose ACD of the eyelids, where the skin is particularly thin and sensitive.² Additionally, ingredients of ophthalmic medications are known to have an especially high false-negative rate with standard patch testing and may require repeated testing with higher drug concentrations or modified patch testing procedures (eg, open testing, scratch-patch testing).^1,59

Treatment

Management of ACD involves allergen avoidance, typically dictated by patch test results.¹⁰ Allergen avoidance may be facilitated using online resources such as the Contact Allergen Management Program (https://www.acdscamp.org/) created by the American Contact Dermatitis Society.^10,18 Patient counseling following patch testing is crucial to educating patients about sources of potential allergen exposures and strategies for avoidance. In the case of eyelid dermatitis, it is particularly important to consider exposure to airborne allergens such as fragrances.¹⁶ Fragrance avoidance is uniquely difficult, as labelling standards in the United States currently do not require disclosure of specific fragrance components.³³ Additionally, products labelled as unscented may still contain fragrances. As such, some patients with fragrance allergy may need to carefully avoid all products containing fragrances.³³

In addition to allergen avoidance, eyelid ACD may be treated with topical medications (eg, steroids, calcineurin inhibitors, Janus kinase inhibitors); however, these same topical medications also can cause ACD due to some ingredients such as propylene glycol.¹⁰ Topical steroids should be used with caution on the eyelids given the risk for atrophy, cataracts, and glaucoma.¹

Final Interpretation

Eyelid dermatitis is a common dermatologic condition most frequently caused by ACD due to exposure to allergens in cosmetic products, ophthalmic medications, nail lacquers, and jewelry, among many other potential sources. The most common allergens causing eyelid dermatitis include metals (particularly nickel), fragrances, preservatives, acrylates, and topical medications. Eyelid ACD is diagnosed via patch testing, and the mainstay of treatment is strict allergen avoidance. Patient counseling is vital for successful allergen avoidance and resolution of eyelid ACD.

THE DIAGNOSIS: Dengue Hemorrhagic Fever

The retiform purpura observed in our patient was suggestive of a vasculitic, thrombotic, or embolic etiology. Dengue IgM serologic testing performed based on her extensive travel history and recent return from a dengue-endemic area was positive, indicating acute infection. A clinical diagnosis of dengue hemorrhagic fever (DHF) was made based on the hemorrhagic appearance of the lesion. Histopathology revealed leukocytoclastic vasculitis (Figure). Anti–double-stranded DNA, antideoxyribonuclease, C3 and C4, CH50 (total hemolytic complement), antineutrophil cytoplasmic antibodies, HIV, and hepatitis B virus tests were normal. Direct immunofluorescence was negative.

Dengue virus is a single-stranded RNA virus transmitted by Aedes aegypti and Aedes albopictus mosquitoes and is one of the most prevalent arthropod-borne viruses affecting humans today.^1,2 Infection with the dengue virus generally is seen in travelers visiting tropical regions of Africa, Mexico, South America, South and Central Asia, Southeast Asia, and the Caribbean.¹ The Table shows the global distribution of dengue serotypes from 2000 to 2014.^3,4 There are 4 serotypes of the dengue virus: DENV-1 to DENV-4. Infection with 1 strain elicits longlasting immunity to that strain, but subsequent infection with another strain can result in severe DHF due to antibody cross-reaction.¹

Dengue virus infection ranges from mildly symptomatic to a spectrum of increasingly severe conditions that comprise dengue fever (DF) and DHF, as well as dengue shock syndrome and brain stem hemorrhage, which may be fatal.^2,5 Dengue fever manifests as severe myalgia, fever, headache (usually retro-orbital), arthralgia, erythema, and rubelliform exanthema.⁶ The frequency of skin eruptions in patients with DF varies with the virus strain and outbreaks.⁷ The lesions initially develop with the onset of fever and manifest as flushing or erythematous mottling of the face, neck, and chest areas.^1,7 The morbilliform eruption develops 2 to 6 days after the onset of the fever, beginning on the trunk and spreading to the face and extremities.^1,7 The rash may become confluent with characteristic sparing of small round areas of normal skin described as white islands in a sea of red.² Verrucous papules on the ears also have been described and may resemble those seen in Cowden syndrome. In patients with prior infection with a different strain of the virus, hemorrhagic lesions may develop, including characteristic retiform purpura, a positive tourniquet test, and the appearance of petechiae on the lower legs. Pruritus and desquamation, especially on the palms and soles, may follow the termination of the eruption.⁷

The differential diagnosis of DF includes measles, rubella, enteroviruses, and influenza. Chikungunya and West Nile viruses in Asia and Africa and the O’nyong-nyong virus in Africa are also arboviruses that cause a clinical picture similar to DF but not DHF. Other diagnostic considerations include phases of scarlet fever, typhoid, malaria, leptospirosis, hepatitis A, and trypanosomal and rickettsial diseases.⁷ The differential diagnosis of DHF includes antineutrophil cytoplasmic antibody–associated vasculitis, rheumatoid vasculitis, and bacterial septic vasculitis.

Acute clinical diagnosis of DF can be challenging because of the nonspecific symptoms that can be seen in almost every infectious disease. Clinical presentation assessment should be confirmed with laboratory testing.⁶ Dengue virus infection usually is confirmed by the identification of viral genomic RNA, antigens, or the antibodies it elicits. Enzyme-linked immunosorbent assay–based serologic tests are cost-effective and easy to perform.⁵ IgM antibodies usually show cross-reactivity with platelets, but the antibody levels are not positively correlated with the severity of DF.⁸ Primary infection with the dengue virus is characterized by the elevation of specific IgM levels that usually occurs 3 to 5 days after symptom onset and persists during the postfebrile stage (up to 30 to 60 days). In secondary infections, the IgM levels usually rise more slowly and reach a lower level than in primary infections.⁹ For both primary and secondary infections, testing IgM levels after the febrile stage may be helpful with the laboratory diagnosis.

Currently, there is no antiviral drug available for dengue. Treatment of dengue infection is symptomatic and supportive.²

Dengue hemorrhagic fever is indicated by a rising hematocrit (≥20%) and a falling platelet count (>100,000/mm³) accompanying clinical signs of hemorrhage. Treatment includes intravenous fluid replacement and careful clinical monitoring of hematocrit levels, platelet count, vitals, urine output, and other signs of shock.⁵ For patients with a history of dengue infection, travel to areas with other serotypes is not recommended.

If any travel to a high-risk area is planned, countryspecific travel recommendations and warnings should be reviewed from the Centers for Disease Control and Prevention’s website (https://wwwnc.cdc.gov/travel/notices/level1/dengue-global). Use of an Environmental Protection Agency–registered insect repellent to avoid mosquito bites and acetaminophen for managing symptoms is advised. During travel, staying in places with window and door screens and using a bed net during sleep are suggested. Long-sleeved shirts and long pants also are preferred. Travelers should see a health care provider if they have symptoms of dengue.¹⁰

African tick bite fever (ATBF) is caused by Rickettsia africae transmitted by Amblyomma ticks. Skin findings in ATBF include erythematous, firm, tender papules with central eschars consistent with the feeding patterns of ticks.¹¹ Histopathology of ATBF usually includes fibrinoid necrosis of vessels in the dermis with a perivascular inflammatory infiltrate and coagulation necrosis of the surrounding dermis consistent with eschar formation.¹² The lack of an eschar weighs against this diagnosis.

African trypanosomiasis (also known as sleeping sickness) is caused by protozoa transmitted by the tsetse fly. A chancrelike, circumscribed, rubbery, indurated red or violaceous nodule measuring 2 to 5 cm in diameter often develops as the earliest cutaneous sign of the disease.¹³ Nonspecific histopathologic findings, such as infiltration of lymphocytes and macrophages and proliferation of endothelial cells and fibroblasts, may be observed.¹⁴ Extravascular parasites have been noted in skin biopsies.¹⁵ In later stages, skin lesions called trypanids may be observed as macular, papular, annular, targetoid, purpuric, and erythematous lesions, and histopathologic findings consistent with vasculitis also may be seen.¹³

Chikungunya virus infection is an acute-onset, mosquito-borne viral disease. Skin manifestations may start with nonspecific, generalized, morbilliform, maculopapular rashes coinciding with fever, which also may be seen initially with DHF. Skin hyperpigmentation, mostly centrofacial and involving the nose (chik sign); purpuric and ecchymotic lesions over the trunk and flexors of limbs in adults, often surmounted by subepidermal bullae and lesions resembling toxic epidermal necrolysis; and nonhealing ulcers in the genital and groin areas are common skin manifestations of chikungunya infection.¹⁶ Intraepithelial splitting with acantholysis and perivascular lymphohistiocytic infiltration may be observed in the histopathology of blistering lesions, which are not consistent with DHF.¹⁷

Zika virus infection is caused by an arbovirus within the Flaviviridae family, which also includes the dengue virus. Initial mucocutaneous findings of the Zika virus include nonspecific diffuse maculopapular eruptions. The eruption generally spares the palms and soles; however, various manifestations including involvement of the palms and soles have been reported.¹⁸ The morbilliform eruption begins on the face and extends to the trunk and extremities. Mild hemorrhagic manifestations, including petechiae and bleeding gums, may be observed. Distinguishing between dengue and Zika virus infection relies on the severity of symptoms and laboratory tests, including polymerase chain reaction or IgM antibody testing.¹⁹ The other conditions listed do not produce hemorrhagic fever.

THE DIAGNOSIS: Dengue Hemorrhagic Fever

The retiform purpura observed in our patient was suggestive of a vasculitic, thrombotic, or embolic etiology. Dengue IgM serologic testing performed based on her extensive travel history and recent return from a dengue-endemic area was positive, indicating acute infection. A clinical diagnosis of dengue hemorrhagic fever (DHF) was made based on the hemorrhagic appearance of the lesion. Histopathology revealed leukocytoclastic vasculitis (Figure). Anti–double-stranded DNA, antideoxyribonuclease, C3 and C4, CH50 (total hemolytic complement), antineutrophil cytoplasmic antibodies, HIV, and hepatitis B virus tests were normal. Direct immunofluorescence was negative.

Dengue virus is a single-stranded RNA virus transmitted by Aedes aegypti and Aedes albopictus mosquitoes and is one of the most prevalent arthropod-borne viruses affecting humans today.^1,2 Infection with the dengue virus generally is seen in travelers visiting tropical regions of Africa, Mexico, South America, South and Central Asia, Southeast Asia, and the Caribbean.¹ The Table shows the global distribution of dengue serotypes from 2000 to 2014.^3,4 There are 4 serotypes of the dengue virus: DENV-1 to DENV-4. Infection with 1 strain elicits longlasting immunity to that strain, but subsequent infection with another strain can result in severe DHF due to antibody cross-reaction.¹

Dengue virus infection ranges from mildly symptomatic to a spectrum of increasingly severe conditions that comprise dengue fever (DF) and DHF, as well as dengue shock syndrome and brain stem hemorrhage, which may be fatal.^2,5 Dengue fever manifests as severe myalgia, fever, headache (usually retro-orbital), arthralgia, erythema, and rubelliform exanthema.⁶ The frequency of skin eruptions in patients with DF varies with the virus strain and outbreaks.⁷ The lesions initially develop with the onset of fever and manifest as flushing or erythematous mottling of the face, neck, and chest areas.^1,7 The morbilliform eruption develops 2 to 6 days after the onset of the fever, beginning on the trunk and spreading to the face and extremities.^1,7 The rash may become confluent with characteristic sparing of small round areas of normal skin described as white islands in a sea of red.² Verrucous papules on the ears also have been described and may resemble those seen in Cowden syndrome. In patients with prior infection with a different strain of the virus, hemorrhagic lesions may develop, including characteristic retiform purpura, a positive tourniquet test, and the appearance of petechiae on the lower legs. Pruritus and desquamation, especially on the palms and soles, may follow the termination of the eruption.⁷

The differential diagnosis of DF includes measles, rubella, enteroviruses, and influenza. Chikungunya and West Nile viruses in Asia and Africa and the O’nyong-nyong virus in Africa are also arboviruses that cause a clinical picture similar to DF but not DHF. Other diagnostic considerations include phases of scarlet fever, typhoid, malaria, leptospirosis, hepatitis A, and trypanosomal and rickettsial diseases.⁷ The differential diagnosis of DHF includes antineutrophil cytoplasmic antibody–associated vasculitis, rheumatoid vasculitis, and bacterial septic vasculitis.

Acute clinical diagnosis of DF can be challenging because of the nonspecific symptoms that can be seen in almost every infectious disease. Clinical presentation assessment should be confirmed with laboratory testing.⁶ Dengue virus infection usually is confirmed by the identification of viral genomic RNA, antigens, or the antibodies it elicits. Enzyme-linked immunosorbent assay–based serologic tests are cost-effective and easy to perform.⁵ IgM antibodies usually show cross-reactivity with platelets, but the antibody levels are not positively correlated with the severity of DF.⁸ Primary infection with the dengue virus is characterized by the elevation of specific IgM levels that usually occurs 3 to 5 days after symptom onset and persists during the postfebrile stage (up to 30 to 60 days). In secondary infections, the IgM levels usually rise more slowly and reach a lower level than in primary infections.⁹ For both primary and secondary infections, testing IgM levels after the febrile stage may be helpful with the laboratory diagnosis.

Currently, there is no antiviral drug available for dengue. Treatment of dengue infection is symptomatic and supportive.²

Dengue hemorrhagic fever is indicated by a rising hematocrit (≥20%) and a falling platelet count (>100,000/mm³) accompanying clinical signs of hemorrhage. Treatment includes intravenous fluid replacement and careful clinical monitoring of hematocrit levels, platelet count, vitals, urine output, and other signs of shock.⁵ For patients with a history of dengue infection, travel to areas with other serotypes is not recommended.

If any travel to a high-risk area is planned, countryspecific travel recommendations and warnings should be reviewed from the Centers for Disease Control and Prevention’s website (https://wwwnc.cdc.gov/travel/notices/level1/dengue-global). Use of an Environmental Protection Agency–registered insect repellent to avoid mosquito bites and acetaminophen for managing symptoms is advised. During travel, staying in places with window and door screens and using a bed net during sleep are suggested. Long-sleeved shirts and long pants also are preferred. Travelers should see a health care provider if they have symptoms of dengue.¹⁰

African tick bite fever (ATBF) is caused by Rickettsia africae transmitted by Amblyomma ticks. Skin findings in ATBF include erythematous, firm, tender papules with central eschars consistent with the feeding patterns of ticks.¹¹ Histopathology of ATBF usually includes fibrinoid necrosis of vessels in the dermis with a perivascular inflammatory infiltrate and coagulation necrosis of the surrounding dermis consistent with eschar formation.¹² The lack of an eschar weighs against this diagnosis.

African trypanosomiasis (also known as sleeping sickness) is caused by protozoa transmitted by the tsetse fly. A chancrelike, circumscribed, rubbery, indurated red or violaceous nodule measuring 2 to 5 cm in diameter often develops as the earliest cutaneous sign of the disease.¹³ Nonspecific histopathologic findings, such as infiltration of lymphocytes and macrophages and proliferation of endothelial cells and fibroblasts, may be observed.¹⁴ Extravascular parasites have been noted in skin biopsies.¹⁵ In later stages, skin lesions called trypanids may be observed as macular, papular, annular, targetoid, purpuric, and erythematous lesions, and histopathologic findings consistent with vasculitis also may be seen.¹³

Chikungunya virus infection is an acute-onset, mosquito-borne viral disease. Skin manifestations may start with nonspecific, generalized, morbilliform, maculopapular rashes coinciding with fever, which also may be seen initially with DHF. Skin hyperpigmentation, mostly centrofacial and involving the nose (chik sign); purpuric and ecchymotic lesions over the trunk and flexors of limbs in adults, often surmounted by subepidermal bullae and lesions resembling toxic epidermal necrolysis; and nonhealing ulcers in the genital and groin areas are common skin manifestations of chikungunya infection.¹⁶ Intraepithelial splitting with acantholysis and perivascular lymphohistiocytic infiltration may be observed in the histopathology of blistering lesions, which are not consistent with DHF.¹⁷

Zika virus infection is caused by an arbovirus within the Flaviviridae family, which also includes the dengue virus. Initial mucocutaneous findings of the Zika virus include nonspecific diffuse maculopapular eruptions. The eruption generally spares the palms and soles; however, various manifestations including involvement of the palms and soles have been reported.¹⁸ The morbilliform eruption begins on the face and extends to the trunk and extremities. Mild hemorrhagic manifestations, including petechiae and bleeding gums, may be observed. Distinguishing between dengue and Zika virus infection relies on the severity of symptoms and laboratory tests, including polymerase chain reaction or IgM antibody testing.¹⁹ The other conditions listed do not produce hemorrhagic fever.

THE DIAGNOSIS: Dengue Hemorrhagic Fever

The retiform purpura observed in our patient was suggestive of a vasculitic, thrombotic, or embolic etiology. Dengue IgM serologic testing performed based on her extensive travel history and recent return from a dengue-endemic area was positive, indicating acute infection. A clinical diagnosis of dengue hemorrhagic fever (DHF) was made based on the hemorrhagic appearance of the lesion. Histopathology revealed leukocytoclastic vasculitis (Figure). Anti–double-stranded DNA, antideoxyribonuclease, C3 and C4, CH50 (total hemolytic complement), antineutrophil cytoplasmic antibodies, HIV, and hepatitis B virus tests were normal. Direct immunofluorescence was negative.

Dengue virus is a single-stranded RNA virus transmitted by Aedes aegypti and Aedes albopictus mosquitoes and is one of the most prevalent arthropod-borne viruses affecting humans today.^1,2 Infection with the dengue virus generally is seen in travelers visiting tropical regions of Africa, Mexico, South America, South and Central Asia, Southeast Asia, and the Caribbean.¹ The Table shows the global distribution of dengue serotypes from 2000 to 2014.^3,4 There are 4 serotypes of the dengue virus: DENV-1 to DENV-4. Infection with 1 strain elicits longlasting immunity to that strain, but subsequent infection with another strain can result in severe DHF due to antibody cross-reaction.¹

Dengue virus infection ranges from mildly symptomatic to a spectrum of increasingly severe conditions that comprise dengue fever (DF) and DHF, as well as dengue shock syndrome and brain stem hemorrhage, which may be fatal.^2,5 Dengue fever manifests as severe myalgia, fever, headache (usually retro-orbital), arthralgia, erythema, and rubelliform exanthema.⁶ The frequency of skin eruptions in patients with DF varies with the virus strain and outbreaks.⁷ The lesions initially develop with the onset of fever and manifest as flushing or erythematous mottling of the face, neck, and chest areas.^1,7 The morbilliform eruption develops 2 to 6 days after the onset of the fever, beginning on the trunk and spreading to the face and extremities.^1,7 The rash may become confluent with characteristic sparing of small round areas of normal skin described as white islands in a sea of red.² Verrucous papules on the ears also have been described and may resemble those seen in Cowden syndrome. In patients with prior infection with a different strain of the virus, hemorrhagic lesions may develop, including characteristic retiform purpura, a positive tourniquet test, and the appearance of petechiae on the lower legs. Pruritus and desquamation, especially on the palms and soles, may follow the termination of the eruption.⁷

The differential diagnosis of DF includes measles, rubella, enteroviruses, and influenza. Chikungunya and West Nile viruses in Asia and Africa and the O’nyong-nyong virus in Africa are also arboviruses that cause a clinical picture similar to DF but not DHF. Other diagnostic considerations include phases of scarlet fever, typhoid, malaria, leptospirosis, hepatitis A, and trypanosomal and rickettsial diseases.⁷ The differential diagnosis of DHF includes antineutrophil cytoplasmic antibody–associated vasculitis, rheumatoid vasculitis, and bacterial septic vasculitis.

Acute clinical diagnosis of DF can be challenging because of the nonspecific symptoms that can be seen in almost every infectious disease. Clinical presentation assessment should be confirmed with laboratory testing.⁶ Dengue virus infection usually is confirmed by the identification of viral genomic RNA, antigens, or the antibodies it elicits. Enzyme-linked immunosorbent assay–based serologic tests are cost-effective and easy to perform.⁵ IgM antibodies usually show cross-reactivity with platelets, but the antibody levels are not positively correlated with the severity of DF.⁸ Primary infection with the dengue virus is characterized by the elevation of specific IgM levels that usually occurs 3 to 5 days after symptom onset and persists during the postfebrile stage (up to 30 to 60 days). In secondary infections, the IgM levels usually rise more slowly and reach a lower level than in primary infections.⁹ For both primary and secondary infections, testing IgM levels after the febrile stage may be helpful with the laboratory diagnosis.

Currently, there is no antiviral drug available for dengue. Treatment of dengue infection is symptomatic and supportive.²

Dengue hemorrhagic fever is indicated by a rising hematocrit (≥20%) and a falling platelet count (>100,000/mm³) accompanying clinical signs of hemorrhage. Treatment includes intravenous fluid replacement and careful clinical monitoring of hematocrit levels, platelet count, vitals, urine output, and other signs of shock.⁵ For patients with a history of dengue infection, travel to areas with other serotypes is not recommended.

If any travel to a high-risk area is planned, countryspecific travel recommendations and warnings should be reviewed from the Centers for Disease Control and Prevention’s website (https://wwwnc.cdc.gov/travel/notices/level1/dengue-global). Use of an Environmental Protection Agency–registered insect repellent to avoid mosquito bites and acetaminophen for managing symptoms is advised. During travel, staying in places with window and door screens and using a bed net during sleep are suggested. Long-sleeved shirts and long pants also are preferred. Travelers should see a health care provider if they have symptoms of dengue.¹⁰

African tick bite fever (ATBF) is caused by Rickettsia africae transmitted by Amblyomma ticks. Skin findings in ATBF include erythematous, firm, tender papules with central eschars consistent with the feeding patterns of ticks.¹¹ Histopathology of ATBF usually includes fibrinoid necrosis of vessels in the dermis with a perivascular inflammatory infiltrate and coagulation necrosis of the surrounding dermis consistent with eschar formation.¹² The lack of an eschar weighs against this diagnosis.

African trypanosomiasis (also known as sleeping sickness) is caused by protozoa transmitted by the tsetse fly. A chancrelike, circumscribed, rubbery, indurated red or violaceous nodule measuring 2 to 5 cm in diameter often develops as the earliest cutaneous sign of the disease.¹³ Nonspecific histopathologic findings, such as infiltration of lymphocytes and macrophages and proliferation of endothelial cells and fibroblasts, may be observed.¹⁴ Extravascular parasites have been noted in skin biopsies.¹⁵ In later stages, skin lesions called trypanids may be observed as macular, papular, annular, targetoid, purpuric, and erythematous lesions, and histopathologic findings consistent with vasculitis also may be seen.¹³

Chikungunya virus infection is an acute-onset, mosquito-borne viral disease. Skin manifestations may start with nonspecific, generalized, morbilliform, maculopapular rashes coinciding with fever, which also may be seen initially with DHF. Skin hyperpigmentation, mostly centrofacial and involving the nose (chik sign); purpuric and ecchymotic lesions over the trunk and flexors of limbs in adults, often surmounted by subepidermal bullae and lesions resembling toxic epidermal necrolysis; and nonhealing ulcers in the genital and groin areas are common skin manifestations of chikungunya infection.¹⁶ Intraepithelial splitting with acantholysis and perivascular lymphohistiocytic infiltration may be observed in the histopathology of blistering lesions, which are not consistent with DHF.¹⁷

Zika virus infection is caused by an arbovirus within the Flaviviridae family, which also includes the dengue virus. Initial mucocutaneous findings of the Zika virus include nonspecific diffuse maculopapular eruptions. The eruption generally spares the palms and soles; however, various manifestations including involvement of the palms and soles have been reported.¹⁸ The morbilliform eruption begins on the face and extends to the trunk and extremities. Mild hemorrhagic manifestations, including petechiae and bleeding gums, may be observed. Distinguishing between dengue and Zika virus infection relies on the severity of symptoms and laboratory tests, including polymerase chain reaction or IgM antibody testing.¹⁹ The other conditions listed do not produce hemorrhagic fever.

To the Editor:

Histopathologic analysis of debulk specimens in Mohs micrographic surgery (MMS) may augment identification of high-risk factors in cutaneous squamous cell carcinoma (cSCC), which may warrant tumor upstaging.¹ Intratumor location has not been studied when looking at these high-risk factors. Herein, we report 4 cSCCs initially categorized as well differentiated that were reclassified as moderate to poorly differentiated on analysis of debulk specimens obtained via shave removal.

An 80-year-old man (patient 1) presented with a tender 2-cm erythematous plaque with dried hemorrhagic crusting on the frontal scalp. He had a history of nonmelanoma skin cancers. A biopsy revealed a ­well-differentiated cSCC, which was upgraded from a T2a tumor to T2b during MMS due to galea involvement. Debulk analysis revealed moderate to poorly differentiated cSCC, with the least-differentiated cells at the deep margin (Figure 1A). Given T2b staging, baseline imaging and radiation therapy were recommended.

To the Editor:

Histopathologic analysis of debulk specimens in Mohs micrographic surgery (MMS) may augment identification of high-risk factors in cutaneous squamous cell carcinoma (cSCC), which may warrant tumor upstaging.¹ Intratumor location has not been studied when looking at these high-risk factors. Herein, we report 4 cSCCs initially categorized as well differentiated that were reclassified as moderate to poorly differentiated on analysis of debulk specimens obtained via shave removal.

An 80-year-old man (patient 1) presented with a tender 2-cm erythematous plaque with dried hemorrhagic crusting on the frontal scalp. He had a history of nonmelanoma skin cancers. A biopsy revealed a ­well-differentiated cSCC, which was upgraded from a T2a tumor to T2b during MMS due to galea involvement. Debulk analysis revealed moderate to poorly differentiated cSCC, with the least-differentiated cells at the deep margin (Figure 1A). Given T2b staging, baseline imaging and radiation therapy were recommended.

To the Editor:

Histopathologic analysis of debulk specimens in Mohs micrographic surgery (MMS) may augment identification of high-risk factors in cutaneous squamous cell carcinoma (cSCC), which may warrant tumor upstaging.¹ Intratumor location has not been studied when looking at these high-risk factors. Herein, we report 4 cSCCs initially categorized as well differentiated that were reclassified as moderate to poorly differentiated on analysis of debulk specimens obtained via shave removal.

An 80-year-old man (patient 1) presented with a tender 2-cm erythematous plaque with dried hemorrhagic crusting on the frontal scalp. He had a history of nonmelanoma skin cancers. A biopsy revealed a ­well-differentiated cSCC, which was upgraded from a T2a tumor to T2b during MMS due to galea involvement. Debulk analysis revealed moderate to poorly differentiated cSCC, with the least-differentiated cells at the deep margin (Figure 1A). Given T2b staging, baseline imaging and radiation therapy were recommended.

The mango tree (Mangifera indica) produces ­nutrient-dense fruit—known colloquially as the “king of fruits”—that is widely consumed across the world. Native to southern Asia, the mango tree is a member of the Anacardiaceae family, a large family of flowering, fruit-bearing plants.¹ Many members of the Anacardiaceae family, which includes poison ivy and poison oak, are known to produce urushiol, a skin irritant associated with allergic contact dermatitis (ACD).² Interestingly, despite its widespread consumption and categorization in the Anacardiaceae family, allergic reactions to mango are comparatively rare; they occur as either immediate type I hypersensitivity reactions manifesting with rapid-onset symptoms such as urticaria, wheezing, and angioedema, or delayed type IV hypersensitivity reactions manifesting as ACD.³ Although exposure to components of the mango tree has been most characteristically linked to type IV hypersensitivity reactions, there remain fewer than 40 reported cases of mango-induced ACD since it was first described in 1939.⁴

Evaluation of ACD most commonly includes a thorough clinical assessment with diagnostic support from patch testing and histopathologic review following skin biopsy. In recent years, reflectance confocal microscopy (RCM) has shown promising potential to join the ­repertoire of diagnostic tools for ACD by enabling dynamic and high-resolution imaging of contact dermatitis in vivo.^5-10 Reflectance confocal microscopy is a noninvasive optical imaging technique that uses a low-energy diode laser to penetrate the layers of the skin. The resulting reflected light generates images that facilitate visualization of cutaneous structures to the depth of the papillary dermis.¹¹ While it is most commonly used in skin cancer diagnostics, preliminary studies also have shown an emerging role for RCM in the evaluation of eczematous and inflammatory skin disease, including contact dermatitis.^5-10 Herein, we present a unique case of mango sap–induced ACD imaged and diagnosed in real time via RCM.

Case Report

A 39-year-old woman presented to our clinic with a pruritic vesicular eruption on the right leg of 2 weeks’ duration that initially had developed within 7 days of exposure to mango tree sap (Figure 1). The patient reported having experienced similar pruritic eruptions in the past following contact with mango sap while eating mangos but denied any history of reactions from ingestion of the fruit. She also reported a history of robust reactions to poison ivy; however, a timeline specifying the order of first exposure to these irritants was unknown. She denied any personal or family history of atopic conditions.

The affected skin was imaged in real time during clinic using RCM, which showed an inflammatory infiltrate represented by dark spongiotic vesicles containing bright cells (Figure 2). Additional RCM imaging at the level of the stratum spinosum showed dark spongiotic areas with bright inflammatory cells infiltrating the vesicles, which were surrounded by normal skin showing a typical epidermal honeycomb pattern (Figure 3). These findings were diagnostic of ACD secondary to exposure to mango sap. The patient was advised to apply clobetasol cream 0.05% to the affected area. Notable improvement of the rash was noted within 10 days of treatment.

Comment

Exposure to the mango tree and its fruit is a rare cause of ACD, with few reported cases in the literature. The majority of known instances have occurred in non–mango-cultivating countries, largely the United States, although cases also have been reported in Canada, Australia, France, Japan, and Thailand.^3,12 Mango-induced contact allergy follows a roughly equal distribution between males and females and most often occurs in young adults during the third and fourth decades of life.^4,12-21 Importantly, delayed-type hypersensitivity reactions to mango can manifest as either localized or systemic ACD. Localized ACD can be induced via direct contact with the mango tree and its components or ingestion of the fruit.^3,12,22 Conversely, systemic ACD is primarily stimulated by ingestion of the fruit. In our case, the patient had no history of allergy following mango ingestion, and her ACD was prompted by isolated contact with mango sap. The time from exposure to symptom onset of known instances of mango ACD varies widely, ranging from less than 24 hours to as long as 9 days.^3,12 Diagnosis of mango-induced ACD largely is guided by clinical findings. Presenting symptoms often include an eczematous, vesicular, pruritic rash on affected areas of the skin, frequently the head, neck, and extremities. Patients also commonly present with linear papulovesicular lesions and periorbital or perioral edema.

The suspected allergens responsible for mango-induced ACD are derived from resorcinol—specifically heptadecadienyl resorcinol, heptadecenyl resorcinol, and pentadecyl resorcinol, which are collectively known as mango allergens.²³ These allergens can be found within the pulp and skin of the mango fruit as well as in the bark and leaves of the mango tree, which may explain observed allergic reactions to components of both the mango fruit and tree.¹² Similar to these resorcinol derivatives, the urushiol resin found in poison ivy and poison oak is a catechol derivative.² Importantly, both resorcinols and catechols are isomers of the same aromatic ­phenol—dihydroxybenzene. Because of these similarities, it is thought that the allergens in mangos may cross-react with urushiol in poison ivy or poison oak.²³ Alongside their shared categorization in the Anacardiaceae family, it is hypothesized that this cross-reactivity underlies the sensitization that has been noted between mango and poison ivy or poison oak exposure.^12,23,24 Thus, ACD often can occur on initial contact with the mango tree or its components, as a prior exposure to poison ivy or poison oak may serve as the inciting factor for hypersensitization. The majority of reported cases in the literature also occurred in countries where exposure to poison ivy and poison oak are common, further supporting the notion that these compounds may provide a sensitizing trigger for a future mango contact allergy.¹²

A detailed clinical history combined with adjunctive diagnostic support from patch testing and histopathology of biopsied skin lesions classically are used in the diagnosis of mango-induced ACD. Due to its ability to provide quick and noninvasive in vivo imaging of cutaneous lesions, RCM's applications have expanded to include evaluation of inflammatory skin diseases such as contact dermatitis. Many features of contact dermatitis identified via RCM are common between ACD and irritant contact dermatitis (ICD) and include disruption of the stratum corneum, parakeratosis, vesiculation, spongiosis, and exocytosis.^6,10,25 Studies also have described features shown via RCM that are unique to ACD, including vasodilation and intercellular edema, compared to more distinct targetoid keratinocytes and detached corneocytes seen in ICD.^6,10,25 Studies by Astner et al^5,6 demonstrated a wide range of sensitivity from 52% to 96% and a high specificity of RCM greater than 95% for many of the aforementioned features of contact dermatitis, including disruption of the stratum corneum, parakeratosis, spongiosis, and exocytosis. Additional studies have further strengthened these findings, demonstrating sensitivity and specificity values of 83% and 92% for contact dermatitis under RCM, respectively.²⁶ Importantly, given the similarities and potentially large overlap of features between ACD and ICD identified via RCM as well as findings seen on physical examination and histopathology, an emphasis on clinical correlation is essential when differentiating between these 2 variants of contact dermatitis. Thus, taken in consideration with clinical contexts, RCM has shown potent diagnostic accuracy and great potential to support the evaluation of ACD alongside patch testing and histopathology.

Final Thoughts

Contact allergy to the mango tree and its components is uncommon. We report a unique case of mango sap–induced ACD evaluated and diagnosed via dynamic visualization under RCM. As a noninvasive and reproducible imaging technique with resolutions comparable to histopathologic analysis, RCM is a promising tool that can be used to support the diagnostic evaluation of ACD.

The mango tree (Mangifera indica) produces ­nutrient-dense fruit—known colloquially as the “king of fruits”—that is widely consumed across the world. Native to southern Asia, the mango tree is a member of the Anacardiaceae family, a large family of flowering, fruit-bearing plants.¹ Many members of the Anacardiaceae family, which includes poison ivy and poison oak, are known to produce urushiol, a skin irritant associated with allergic contact dermatitis (ACD).² Interestingly, despite its widespread consumption and categorization in the Anacardiaceae family, allergic reactions to mango are comparatively rare; they occur as either immediate type I hypersensitivity reactions manifesting with rapid-onset symptoms such as urticaria, wheezing, and angioedema, or delayed type IV hypersensitivity reactions manifesting as ACD.³ Although exposure to components of the mango tree has been most characteristically linked to type IV hypersensitivity reactions, there remain fewer than 40 reported cases of mango-induced ACD since it was first described in 1939.⁴

Evaluation of ACD most commonly includes a thorough clinical assessment with diagnostic support from patch testing and histopathologic review following skin biopsy. In recent years, reflectance confocal microscopy (RCM) has shown promising potential to join the ­repertoire of diagnostic tools for ACD by enabling dynamic and high-resolution imaging of contact dermatitis in vivo.^5-10 Reflectance confocal microscopy is a noninvasive optical imaging technique that uses a low-energy diode laser to penetrate the layers of the skin. The resulting reflected light generates images that facilitate visualization of cutaneous structures to the depth of the papillary dermis.¹¹ While it is most commonly used in skin cancer diagnostics, preliminary studies also have shown an emerging role for RCM in the evaluation of eczematous and inflammatory skin disease, including contact dermatitis.^5-10 Herein, we present a unique case of mango sap–induced ACD imaged and diagnosed in real time via RCM.

Case Report

A 39-year-old woman presented to our clinic with a pruritic vesicular eruption on the right leg of 2 weeks’ duration that initially had developed within 7 days of exposure to mango tree sap (Figure 1). The patient reported having experienced similar pruritic eruptions in the past following contact with mango sap while eating mangos but denied any history of reactions from ingestion of the fruit. She also reported a history of robust reactions to poison ivy; however, a timeline specifying the order of first exposure to these irritants was unknown. She denied any personal or family history of atopic conditions.

The affected skin was imaged in real time during clinic using RCM, which showed an inflammatory infiltrate represented by dark spongiotic vesicles containing bright cells (Figure 2). Additional RCM imaging at the level of the stratum spinosum showed dark spongiotic areas with bright inflammatory cells infiltrating the vesicles, which were surrounded by normal skin showing a typical epidermal honeycomb pattern (Figure 3). These findings were diagnostic of ACD secondary to exposure to mango sap. The patient was advised to apply clobetasol cream 0.05% to the affected area. Notable improvement of the rash was noted within 10 days of treatment.

Comment

Exposure to the mango tree and its fruit is a rare cause of ACD, with few reported cases in the literature. The majority of known instances have occurred in non–mango-cultivating countries, largely the United States, although cases also have been reported in Canada, Australia, France, Japan, and Thailand.^3,12 Mango-induced contact allergy follows a roughly equal distribution between males and females and most often occurs in young adults during the third and fourth decades of life.^4,12-21 Importantly, delayed-type hypersensitivity reactions to mango can manifest as either localized or systemic ACD. Localized ACD can be induced via direct contact with the mango tree and its components or ingestion of the fruit.^3,12,22 Conversely, systemic ACD is primarily stimulated by ingestion of the fruit. In our case, the patient had no history of allergy following mango ingestion, and her ACD was prompted by isolated contact with mango sap. The time from exposure to symptom onset of known instances of mango ACD varies widely, ranging from less than 24 hours to as long as 9 days.^3,12 Diagnosis of mango-induced ACD largely is guided by clinical findings. Presenting symptoms often include an eczematous, vesicular, pruritic rash on affected areas of the skin, frequently the head, neck, and extremities. Patients also commonly present with linear papulovesicular lesions and periorbital or perioral edema.

The suspected allergens responsible for mango-induced ACD are derived from resorcinol—specifically heptadecadienyl resorcinol, heptadecenyl resorcinol, and pentadecyl resorcinol, which are collectively known as mango allergens.²³ These allergens can be found within the pulp and skin of the mango fruit as well as in the bark and leaves of the mango tree, which may explain observed allergic reactions to components of both the mango fruit and tree.¹² Similar to these resorcinol derivatives, the urushiol resin found in poison ivy and poison oak is a catechol derivative.² Importantly, both resorcinols and catechols are isomers of the same aromatic ­phenol—dihydroxybenzene. Because of these similarities, it is thought that the allergens in mangos may cross-react with urushiol in poison ivy or poison oak.²³ Alongside their shared categorization in the Anacardiaceae family, it is hypothesized that this cross-reactivity underlies the sensitization that has been noted between mango and poison ivy or poison oak exposure.^12,23,24 Thus, ACD often can occur on initial contact with the mango tree or its components, as a prior exposure to poison ivy or poison oak may serve as the inciting factor for hypersensitization. The majority of reported cases in the literature also occurred in countries where exposure to poison ivy and poison oak are common, further supporting the notion that these compounds may provide a sensitizing trigger for a future mango contact allergy.¹²

A detailed clinical history combined with adjunctive diagnostic support from patch testing and histopathology of biopsied skin lesions classically are used in the diagnosis of mango-induced ACD. Due to its ability to provide quick and noninvasive in vivo imaging of cutaneous lesions, RCM's applications have expanded to include evaluation of inflammatory skin diseases such as contact dermatitis. Many features of contact dermatitis identified via RCM are common between ACD and irritant contact dermatitis (ICD) and include disruption of the stratum corneum, parakeratosis, vesiculation, spongiosis, and exocytosis.^6,10,25 Studies also have described features shown via RCM that are unique to ACD, including vasodilation and intercellular edema, compared to more distinct targetoid keratinocytes and detached corneocytes seen in ICD.^6,10,25 Studies by Astner et al^5,6 demonstrated a wide range of sensitivity from 52% to 96% and a high specificity of RCM greater than 95% for many of the aforementioned features of contact dermatitis, including disruption of the stratum corneum, parakeratosis, spongiosis, and exocytosis. Additional studies have further strengthened these findings, demonstrating sensitivity and specificity values of 83% and 92% for contact dermatitis under RCM, respectively.²⁶ Importantly, given the similarities and potentially large overlap of features between ACD and ICD identified via RCM as well as findings seen on physical examination and histopathology, an emphasis on clinical correlation is essential when differentiating between these 2 variants of contact dermatitis. Thus, taken in consideration with clinical contexts, RCM has shown potent diagnostic accuracy and great potential to support the evaluation of ACD alongside patch testing and histopathology.

Final Thoughts

Contact allergy to the mango tree and its components is uncommon. We report a unique case of mango sap–induced ACD evaluated and diagnosed via dynamic visualization under RCM. As a noninvasive and reproducible imaging technique with resolutions comparable to histopathologic analysis, RCM is a promising tool that can be used to support the diagnostic evaluation of ACD.

The mango tree (Mangifera indica) produces ­nutrient-dense fruit—known colloquially as the “king of fruits”—that is widely consumed across the world. Native to southern Asia, the mango tree is a member of the Anacardiaceae family, a large family of flowering, fruit-bearing plants.¹ Many members of the Anacardiaceae family, which includes poison ivy and poison oak, are known to produce urushiol, a skin irritant associated with allergic contact dermatitis (ACD).² Interestingly, despite its widespread consumption and categorization in the Anacardiaceae family, allergic reactions to mango are comparatively rare; they occur as either immediate type I hypersensitivity reactions manifesting with rapid-onset symptoms such as urticaria, wheezing, and angioedema, or delayed type IV hypersensitivity reactions manifesting as ACD.³ Although exposure to components of the mango tree has been most characteristically linked to type IV hypersensitivity reactions, there remain fewer than 40 reported cases of mango-induced ACD since it was first described in 1939.⁴

Evaluation of ACD most commonly includes a thorough clinical assessment with diagnostic support from patch testing and histopathologic review following skin biopsy. In recent years, reflectance confocal microscopy (RCM) has shown promising potential to join the ­repertoire of diagnostic tools for ACD by enabling dynamic and high-resolution imaging of contact dermatitis in vivo.^5-10 Reflectance confocal microscopy is a noninvasive optical imaging technique that uses a low-energy diode laser to penetrate the layers of the skin. The resulting reflected light generates images that facilitate visualization of cutaneous structures to the depth of the papillary dermis.¹¹ While it is most commonly used in skin cancer diagnostics, preliminary studies also have shown an emerging role for RCM in the evaluation of eczematous and inflammatory skin disease, including contact dermatitis.^5-10 Herein, we present a unique case of mango sap–induced ACD imaged and diagnosed in real time via RCM.

Case Report

A 39-year-old woman presented to our clinic with a pruritic vesicular eruption on the right leg of 2 weeks’ duration that initially had developed within 7 days of exposure to mango tree sap (Figure 1). The patient reported having experienced similar pruritic eruptions in the past following contact with mango sap while eating mangos but denied any history of reactions from ingestion of the fruit. She also reported a history of robust reactions to poison ivy; however, a timeline specifying the order of first exposure to these irritants was unknown. She denied any personal or family history of atopic conditions.

The affected skin was imaged in real time during clinic using RCM, which showed an inflammatory infiltrate represented by dark spongiotic vesicles containing bright cells (Figure 2). Additional RCM imaging at the level of the stratum spinosum showed dark spongiotic areas with bright inflammatory cells infiltrating the vesicles, which were surrounded by normal skin showing a typical epidermal honeycomb pattern (Figure 3). These findings were diagnostic of ACD secondary to exposure to mango sap. The patient was advised to apply clobetasol cream 0.05% to the affected area. Notable improvement of the rash was noted within 10 days of treatment.

Comment

Exposure to the mango tree and its fruit is a rare cause of ACD, with few reported cases in the literature. The majority of known instances have occurred in non–mango-cultivating countries, largely the United States, although cases also have been reported in Canada, Australia, France, Japan, and Thailand.^3,12 Mango-induced contact allergy follows a roughly equal distribution between males and females and most often occurs in young adults during the third and fourth decades of life.^4,12-21 Importantly, delayed-type hypersensitivity reactions to mango can manifest as either localized or systemic ACD. Localized ACD can be induced via direct contact with the mango tree and its components or ingestion of the fruit.^3,12,22 Conversely, systemic ACD is primarily stimulated by ingestion of the fruit. In our case, the patient had no history of allergy following mango ingestion, and her ACD was prompted by isolated contact with mango sap. The time from exposure to symptom onset of known instances of mango ACD varies widely, ranging from less than 24 hours to as long as 9 days.^3,12 Diagnosis of mango-induced ACD largely is guided by clinical findings. Presenting symptoms often include an eczematous, vesicular, pruritic rash on affected areas of the skin, frequently the head, neck, and extremities. Patients also commonly present with linear papulovesicular lesions and periorbital or perioral edema.

The suspected allergens responsible for mango-induced ACD are derived from resorcinol—specifically heptadecadienyl resorcinol, heptadecenyl resorcinol, and pentadecyl resorcinol, which are collectively known as mango allergens.²³ These allergens can be found within the pulp and skin of the mango fruit as well as in the bark and leaves of the mango tree, which may explain observed allergic reactions to components of both the mango fruit and tree.¹² Similar to these resorcinol derivatives, the urushiol resin found in poison ivy and poison oak is a catechol derivative.² Importantly, both resorcinols and catechols are isomers of the same aromatic ­phenol—dihydroxybenzene. Because of these similarities, it is thought that the allergens in mangos may cross-react with urushiol in poison ivy or poison oak.²³ Alongside their shared categorization in the Anacardiaceae family, it is hypothesized that this cross-reactivity underlies the sensitization that has been noted between mango and poison ivy or poison oak exposure.^12,23,24 Thus, ACD often can occur on initial contact with the mango tree or its components, as a prior exposure to poison ivy or poison oak may serve as the inciting factor for hypersensitization. The majority of reported cases in the literature also occurred in countries where exposure to poison ivy and poison oak are common, further supporting the notion that these compounds may provide a sensitizing trigger for a future mango contact allergy.¹²

A detailed clinical history combined with adjunctive diagnostic support from patch testing and histopathology of biopsied skin lesions classically are used in the diagnosis of mango-induced ACD. Due to its ability to provide quick and noninvasive in vivo imaging of cutaneous lesions, RCM's applications have expanded to include evaluation of inflammatory skin diseases such as contact dermatitis. Many features of contact dermatitis identified via RCM are common between ACD and irritant contact dermatitis (ICD) and include disruption of the stratum corneum, parakeratosis, vesiculation, spongiosis, and exocytosis.^6,10,25 Studies also have described features shown via RCM that are unique to ACD, including vasodilation and intercellular edema, compared to more distinct targetoid keratinocytes and detached corneocytes seen in ICD.^6,10,25 Studies by Astner et al^5,6 demonstrated a wide range of sensitivity from 52% to 96% and a high specificity of RCM greater than 95% for many of the aforementioned features of contact dermatitis, including disruption of the stratum corneum, parakeratosis, spongiosis, and exocytosis. Additional studies have further strengthened these findings, demonstrating sensitivity and specificity values of 83% and 92% for contact dermatitis under RCM, respectively.²⁶ Importantly, given the similarities and potentially large overlap of features between ACD and ICD identified via RCM as well as findings seen on physical examination and histopathology, an emphasis on clinical correlation is essential when differentiating between these 2 variants of contact dermatitis. Thus, taken in consideration with clinical contexts, RCM has shown potent diagnostic accuracy and great potential to support the evaluation of ACD alongside patch testing and histopathology.

Final Thoughts

Contact allergy to the mango tree and its components is uncommon. We report a unique case of mango sap–induced ACD evaluated and diagnosed via dynamic visualization under RCM. As a noninvasive and reproducible imaging technique with resolutions comparable to histopathologic analysis, RCM is a promising tool that can be used to support the diagnostic evaluation of ACD.

To the Editor:

Mutations of the BRAF protein kinase gene are implicated in a variety of malignancies.¹ BRAF mutations in malignancies cause the mitogen-activated protein kinase (MAPK) pathway to become constitutively active, which results in unchecked cellular proliferation,^2,3 making the BRAF mutation an attractive target for inhibition with pharmacologic agents to potentially halt cancer growth.⁴ Vemurafenib—the first selective BRAF inhibitor used in clinical practice—initially was approved by the US Food and Drug Administration in 2011. The approval of dabrafenib followed in 2013 and most recently encorafenib in 2018.⁵

Although targeted treatment of BRAF-mutated malignancies with BRAF inhibitors has become common, it often is associated with cutaneous adverse events (AEs), such as rash, pruritus, photosensitivity, actinic keratosis, and verrucous keratosis. Some reports demonstrate these events in up to 95% of patients undergoing BRAF inhibitor treatment.⁶ In several cases the eruption of verrucous keratoses is among the most common cutaneous AEs seen among patients receiving BRAF inhibitor treatment.^5-7

In general, lesions can appear days to months after therapy is initiated and may resolve after switching to dual therapy with a MEK inhibitor or with complete cessation of BRAF inhibitor therapy.^5,7,8 One case of spontaneous resolution of vemurafenib-associated panniculitis during ongoing BRAF inhibitor therapy has been reported⁹; however, spontaneous resolution of cutaneous AEs is uncommon. Herein, we describe verrucous keratoses in a patient undergoing treatment with encorafenib that resolved spontaneously despite ongoing BRAF inhibitor therapy.

A 61-year-old woman presented to the emergency department with pain in the right lower quadrant. Computed tomography (CT) of the abdomen and pelvis revealed a large ovarian mass. Subsequent bloodwork revealed elevated carcinoembryonic antigen levels. The patient underwent a hysterectomy, bilateral salpingo-oophorectomy, omentectomy, right hemicolectomy with ileotransverse side-to-side anastomosis, right pelvic lymph node reduction, and complete cytoreduction. Histopathology revealed an adenocarcinoma of the cecum with tumor invasion into the visceral peritoneum and metastases to the left ovary, fallopian tube, and omentum. A BRAF V600E mutation was detected.

Two months after the initial presentation, the patient started her first cycle of chemotherapy with a combination of folinic acid, fluorouracil, and oxaliplatin. She completed 11 cycles of this regimen, then was switched to capecitabine and oxaliplatin for an additional 2 cycles due to insurance concerns. At the end of treatment, there was no evidence of disease on CT, thus the patient was followed with observation. However, she presented 10 months later to the emergency department with abdominal pain, and CT revealed new lesions in the liver that were concerning for potential metastases. She started oral encorafenib 300 mg/d and intravenous cetuximab 500 mg weekly; after 1 week, encorafenib was reduced to 150 mg/d due to nausea and loss of appetite. Within 2 weeks of starting treatment, the patient reported the relatively abrupt appearance of more than 50 small papules across the shoulders and back (Figure 1A). She was referred to dermatology, and shave biopsies of 2 lesions—one from the left anterior thigh, the other from the right posterior shoulder—revealed verrucous keratosis pathology (Figure 2). At this time, encorafenib was increased again to 300 mg/d as the patient had been tolerating the reduced dose. She continued to report the appearance of new lesions for the next 3 months, after which the lesions were stable for approximately 2 months. By 2.5 months after initiation of therapy, the patient had ­undergone CT demonstrating resolution of the liver lesions. At 5 months of therapy, the patient reported a stable to slightly reduced number of skin lesions but had begun to experience worsening joint pain, and the dosage of encorafenib was reduced to 225 mg/d. At 7 months of therapy, the dosage was further reduced to 150 mg/d due to persistent arthralgia. A follow-up examination at 10 months of therapy showed improvement in the number and size of the verrucous keratoses, and near resolution was seen by 14 months after the initial onset of the lesions (Figure 1B). At 20 months after initial onset, only 1 remaining verrucous keratosis was identified on physical examination and biopsy. The patient had continued a regimen of encorafenib 150 mg/d and weekly intravenous 500 mg cetuximab up to this point. Over the entire time period that the patient was seen, up to 12 lesions located in high-friction areas had become irritated and were treated with cryotherapy, but this contributed only minorly to the patient’s overall presentation.

To the Editor:

Mutations of the BRAF protein kinase gene are implicated in a variety of malignancies.¹ BRAF mutations in malignancies cause the mitogen-activated protein kinase (MAPK) pathway to become constitutively active, which results in unchecked cellular proliferation,^2,3 making the BRAF mutation an attractive target for inhibition with pharmacologic agents to potentially halt cancer growth.⁴ Vemurafenib—the first selective BRAF inhibitor used in clinical practice—initially was approved by the US Food and Drug Administration in 2011. The approval of dabrafenib followed in 2013 and most recently encorafenib in 2018.⁵

Although targeted treatment of BRAF-mutated malignancies with BRAF inhibitors has become common, it often is associated with cutaneous adverse events (AEs), such as rash, pruritus, photosensitivity, actinic keratosis, and verrucous keratosis. Some reports demonstrate these events in up to 95% of patients undergoing BRAF inhibitor treatment.⁶ In several cases the eruption of verrucous keratoses is among the most common cutaneous AEs seen among patients receiving BRAF inhibitor treatment.^5-7

In general, lesions can appear days to months after therapy is initiated and may resolve after switching to dual therapy with a MEK inhibitor or with complete cessation of BRAF inhibitor therapy.^5,7,8 One case of spontaneous resolution of vemurafenib-associated panniculitis during ongoing BRAF inhibitor therapy has been reported⁹; however, spontaneous resolution of cutaneous AEs is uncommon. Herein, we describe verrucous keratoses in a patient undergoing treatment with encorafenib that resolved spontaneously despite ongoing BRAF inhibitor therapy.

A 61-year-old woman presented to the emergency department with pain in the right lower quadrant. Computed tomography (CT) of the abdomen and pelvis revealed a large ovarian mass. Subsequent bloodwork revealed elevated carcinoembryonic antigen levels. The patient underwent a hysterectomy, bilateral salpingo-oophorectomy, omentectomy, right hemicolectomy with ileotransverse side-to-side anastomosis, right pelvic lymph node reduction, and complete cytoreduction. Histopathology revealed an adenocarcinoma of the cecum with tumor invasion into the visceral peritoneum and metastases to the left ovary, fallopian tube, and omentum. A BRAF V600E mutation was detected.

Two months after the initial presentation, the patient started her first cycle of chemotherapy with a combination of folinic acid, fluorouracil, and oxaliplatin. She completed 11 cycles of this regimen, then was switched to capecitabine and oxaliplatin for an additional 2 cycles due to insurance concerns. At the end of treatment, there was no evidence of disease on CT, thus the patient was followed with observation. However, she presented 10 months later to the emergency department with abdominal pain, and CT revealed new lesions in the liver that were concerning for potential metastases. She started oral encorafenib 300 mg/d and intravenous cetuximab 500 mg weekly; after 1 week, encorafenib was reduced to 150 mg/d due to nausea and loss of appetite. Within 2 weeks of starting treatment, the patient reported the relatively abrupt appearance of more than 50 small papules across the shoulders and back (Figure 1A). She was referred to dermatology, and shave biopsies of 2 lesions—one from the left anterior thigh, the other from the right posterior shoulder—revealed verrucous keratosis pathology (Figure 2). At this time, encorafenib was increased again to 300 mg/d as the patient had been tolerating the reduced dose. She continued to report the appearance of new lesions for the next 3 months, after which the lesions were stable for approximately 2 months. By 2.5 months after initiation of therapy, the patient had ­undergone CT demonstrating resolution of the liver lesions. At 5 months of therapy, the patient reported a stable to slightly reduced number of skin lesions but had begun to experience worsening joint pain, and the dosage of encorafenib was reduced to 225 mg/d. At 7 months of therapy, the dosage was further reduced to 150 mg/d due to persistent arthralgia. A follow-up examination at 10 months of therapy showed improvement in the number and size of the verrucous keratoses, and near resolution was seen by 14 months after the initial onset of the lesions (Figure 1B). At 20 months after initial onset, only 1 remaining verrucous keratosis was identified on physical examination and biopsy. The patient had continued a regimen of encorafenib 150 mg/d and weekly intravenous 500 mg cetuximab up to this point. Over the entire time period that the patient was seen, up to 12 lesions located in high-friction areas had become irritated and were treated with cryotherapy, but this contributed only minorly to the patient’s overall presentation.

To the Editor:

Mutations of the BRAF protein kinase gene are implicated in a variety of malignancies.¹ BRAF mutations in malignancies cause the mitogen-activated protein kinase (MAPK) pathway to become constitutively active, which results in unchecked cellular proliferation,^2,3 making the BRAF mutation an attractive target for inhibition with pharmacologic agents to potentially halt cancer growth.⁴ Vemurafenib—the first selective BRAF inhibitor used in clinical practice—initially was approved by the US Food and Drug Administration in 2011. The approval of dabrafenib followed in 2013 and most recently encorafenib in 2018.⁵

Although targeted treatment of BRAF-mutated malignancies with BRAF inhibitors has become common, it often is associated with cutaneous adverse events (AEs), such as rash, pruritus, photosensitivity, actinic keratosis, and verrucous keratosis. Some reports demonstrate these events in up to 95% of patients undergoing BRAF inhibitor treatment.⁶ In several cases the eruption of verrucous keratoses is among the most common cutaneous AEs seen among patients receiving BRAF inhibitor treatment.^5-7

In general, lesions can appear days to months after therapy is initiated and may resolve after switching to dual therapy with a MEK inhibitor or with complete cessation of BRAF inhibitor therapy.^5,7,8 One case of spontaneous resolution of vemurafenib-associated panniculitis during ongoing BRAF inhibitor therapy has been reported⁹; however, spontaneous resolution of cutaneous AEs is uncommon. Herein, we describe verrucous keratoses in a patient undergoing treatment with encorafenib that resolved spontaneously despite ongoing BRAF inhibitor therapy.

A 61-year-old woman presented to the emergency department with pain in the right lower quadrant. Computed tomography (CT) of the abdomen and pelvis revealed a large ovarian mass. Subsequent bloodwork revealed elevated carcinoembryonic antigen levels. The patient underwent a hysterectomy, bilateral salpingo-oophorectomy, omentectomy, right hemicolectomy with ileotransverse side-to-side anastomosis, right pelvic lymph node reduction, and complete cytoreduction. Histopathology revealed an adenocarcinoma of the cecum with tumor invasion into the visceral peritoneum and metastases to the left ovary, fallopian tube, and omentum. A BRAF V600E mutation was detected.

Two months after the initial presentation, the patient started her first cycle of chemotherapy with a combination of folinic acid, fluorouracil, and oxaliplatin. She completed 11 cycles of this regimen, then was switched to capecitabine and oxaliplatin for an additional 2 cycles due to insurance concerns. At the end of treatment, there was no evidence of disease on CT, thus the patient was followed with observation. However, she presented 10 months later to the emergency department with abdominal pain, and CT revealed new lesions in the liver that were concerning for potential metastases. She started oral encorafenib 300 mg/d and intravenous cetuximab 500 mg weekly; after 1 week, encorafenib was reduced to 150 mg/d due to nausea and loss of appetite. Within 2 weeks of starting treatment, the patient reported the relatively abrupt appearance of more than 50 small papules across the shoulders and back (Figure 1A). She was referred to dermatology, and shave biopsies of 2 lesions—one from the left anterior thigh, the other from the right posterior shoulder—revealed verrucous keratosis pathology (Figure 2). At this time, encorafenib was increased again to 300 mg/d as the patient had been tolerating the reduced dose. She continued to report the appearance of new lesions for the next 3 months, after which the lesions were stable for approximately 2 months. By 2.5 months after initiation of therapy, the patient had ­undergone CT demonstrating resolution of the liver lesions. At 5 months of therapy, the patient reported a stable to slightly reduced number of skin lesions but had begun to experience worsening joint pain, and the dosage of encorafenib was reduced to 225 mg/d. At 7 months of therapy, the dosage was further reduced to 150 mg/d due to persistent arthralgia. A follow-up examination at 10 months of therapy showed improvement in the number and size of the verrucous keratoses, and near resolution was seen by 14 months after the initial onset of the lesions (Figure 1B). At 20 months after initial onset, only 1 remaining verrucous keratosis was identified on physical examination and biopsy. The patient had continued a regimen of encorafenib 150 mg/d and weekly intravenous 500 mg cetuximab up to this point. Over the entire time period that the patient was seen, up to 12 lesions located in high-friction areas had become irritated and were treated with cryotherapy, but this contributed only minorly to the patient’s overall presentation.

THE DIAGNOSIS: Secondary Syphilis

Histopathology demonstrated a mild superficial perivascular and interstitial infiltrate composed of lymphocytes, histiocytes, and rare plasma cells with a background of extravasated erythrocytes (Figure, A). Treponema pallidum staining highlighted multiple spirochetes along the dermoepidermal junction and in the superficial dermis (Figure, B). Direct immunofluorescence was negative. Laboratory workup revealed a reactive rapid plasma reagin screen with a titer of 1:16 and positive IgG and IgM treponemal antibodies. The patient was diagnosed with secondary syphilis and was treated with a single dose of 2.4 million U of intramuscular benzathine penicillin G, with notable improvement of the rash and arthritis symptoms at 2-week follow-up.

Syphilis is a sexually transmitted infection caused by the spirochete T pallidum that progresses through active and latent stages. The incidence of both the primary and secondary stages of syphilis was at a historic low in the year 2000 and has increased annually since then.¹ Syphilis is more common in men, and men who have sex with men (MSM) are disproportionately affected. Although the incidence of syphilis in MSM has increased since 2000, rates have slowed, with slight decreases in this population between 2019 and 2020.¹ Conversely, rates among women have increased substantially in recent years, suggesting a more recent epidemic affecting heterosexual men and women.²

Classically, the primary stage of syphilis manifests as an asymptomatic papule followed by a painless ulcer (chancre) that heals spontaneously. The secondary stage of syphilis results from dissemination of T pallidum and is characterized by a wide range of mucocutaneous manifestations and prodromal symptoms. The most common cutaneous manifestation is a diffuse, nonpruritic, papulosquamous rash with red-brown scaly macules or papules on the trunk and extremities.³ The palms and soles commonly are involved. Mucosal patches, “snail-track” ulcers in the mouth, and condylomata lata are the characteristic mucosal lesions of secondary syphilis. Mucocutaneous findings typically are preceded by systemic signs including fever, malaise, myalgia, and generalized lymphadenopathy. However, syphilis is considered “the great mimicker,” with new reports of unusual presentations of the disease. In addition to papulosquamous morphologies, pustular, targetoid, psoriasiform, and noduloulcerative (also known as lues maligna) forms of syphilis have been reported.^3-5

The histopathologic features of secondary syphilis also are variable. Classically, secondary syphilis demonstrates vacuolar interface dermatitis and acanthosis with slender elongated rete ridges. Other well-known features include endothelial swelling and the presence of plasma cells in most cases.⁶ However, the histopathologic features of secondary syphilis may vary depending on the morphology of the skin eruption and when the biopsy is taken. Our patient lacked the classic histopathologic features of secondary syphilis. However, because syphilis was in the clinical differential diagnosis, a treponemal stain was ordered and confirmed the diagnosis. Immunohistochemical stains using antibodies to treponemal antigens have a reported sensitivity of 71% to 100% and are highly specific.⁷ Although the combination of endothelial swelling, interstitial inflammation, irregular acanthosis, and elongated rete ridges should raise the possibility of syphilis, a treponemal stain may be useful to identify spirochetes if clinical suspicion exists.⁸

Given our patient’s known history of GPA, leukocytoclastic vasculitis was high on the list of differential diagnoses. However, leukocytoclastic vasculitis most classically manifests as petechiae and palpable purpura, and unlike in secondary syphilis, the palms and soles are less commonly involved. Because our patient’s rash was mainly localized to the lower limbs, the differential also included 2 pigmented purpuric dermatoses (PPDs): progressive pigmentary purpura (Schamberg disease) and purpura annularis telangiectodes (Majocchi disease). Progressive pigmentary purpura is the most common manifestation of PPD and appears as cayenne pepper–colored macules that coalesce into golden brown–pigmented patches on the legs.⁹ Purpura annularis telangiectodes is another variant of PPD that manifests as pinpoint telangiectatic macules that progress to annular hyperpigmented patches with central clearing. Although PPDs frequently occur on the lower extremities, reports of plantar involvement are rare.¹⁰ Annular lichen planus manifests as violaceous papules with a clear center; however, it would be atypical for these lesions to be restricted to the feet and ankles. Palmoplantar lichen planus can mimic secondary syphilis clinically, but these cases manifest as hyperkeratotic pruritic papules on the palms and soles in contrast to the faint brown asymptomatic macules noted in our case.¹¹

Our case highlights an unusual presentation of secondary syphilis and demonstrates the challenge of diagnosing this entity on clinical presentation alone. Because this patient lacked the classic clinical and histopathologic features of secondary syphilis, a skin biopsy with positive immunohistochemical staining for treponemal antigens was necessary to make the diagnosis. Given the variability in presentation of secondary syphilis, a biopsy or serologic testing may be necessary to make a proper diagnosis.

THE DIAGNOSIS: Secondary Syphilis

Histopathology demonstrated a mild superficial perivascular and interstitial infiltrate composed of lymphocytes, histiocytes, and rare plasma cells with a background of extravasated erythrocytes (Figure, A). Treponema pallidum staining highlighted multiple spirochetes along the dermoepidermal junction and in the superficial dermis (Figure, B). Direct immunofluorescence was negative. Laboratory workup revealed a reactive rapid plasma reagin screen with a titer of 1:16 and positive IgG and IgM treponemal antibodies. The patient was diagnosed with secondary syphilis and was treated with a single dose of 2.4 million U of intramuscular benzathine penicillin G, with notable improvement of the rash and arthritis symptoms at 2-week follow-up.

Syphilis is a sexually transmitted infection caused by the spirochete T pallidum that progresses through active and latent stages. The incidence of both the primary and secondary stages of syphilis was at a historic low in the year 2000 and has increased annually since then.¹ Syphilis is more common in men, and men who have sex with men (MSM) are disproportionately affected. Although the incidence of syphilis in MSM has increased since 2000, rates have slowed, with slight decreases in this population between 2019 and 2020.¹ Conversely, rates among women have increased substantially in recent years, suggesting a more recent epidemic affecting heterosexual men and women.²

Classically, the primary stage of syphilis manifests as an asymptomatic papule followed by a painless ulcer (chancre) that heals spontaneously. The secondary stage of syphilis results from dissemination of T pallidum and is characterized by a wide range of mucocutaneous manifestations and prodromal symptoms. The most common cutaneous manifestation is a diffuse, nonpruritic, papulosquamous rash with red-brown scaly macules or papules on the trunk and extremities.³ The palms and soles commonly are involved. Mucosal patches, “snail-track” ulcers in the mouth, and condylomata lata are the characteristic mucosal lesions of secondary syphilis. Mucocutaneous findings typically are preceded by systemic signs including fever, malaise, myalgia, and generalized lymphadenopathy. However, syphilis is considered “the great mimicker,” with new reports of unusual presentations of the disease. In addition to papulosquamous morphologies, pustular, targetoid, psoriasiform, and noduloulcerative (also known as lues maligna) forms of syphilis have been reported.^3-5

The histopathologic features of secondary syphilis also are variable. Classically, secondary syphilis demonstrates vacuolar interface dermatitis and acanthosis with slender elongated rete ridges. Other well-known features include endothelial swelling and the presence of plasma cells in most cases.⁶ However, the histopathologic features of secondary syphilis may vary depending on the morphology of the skin eruption and when the biopsy is taken. Our patient lacked the classic histopathologic features of secondary syphilis. However, because syphilis was in the clinical differential diagnosis, a treponemal stain was ordered and confirmed the diagnosis. Immunohistochemical stains using antibodies to treponemal antigens have a reported sensitivity of 71% to 100% and are highly specific.⁷ Although the combination of endothelial swelling, interstitial inflammation, irregular acanthosis, and elongated rete ridges should raise the possibility of syphilis, a treponemal stain may be useful to identify spirochetes if clinical suspicion exists.⁸

Given our patient’s known history of GPA, leukocytoclastic vasculitis was high on the list of differential diagnoses. However, leukocytoclastic vasculitis most classically manifests as petechiae and palpable purpura, and unlike in secondary syphilis, the palms and soles are less commonly involved. Because our patient’s rash was mainly localized to the lower limbs, the differential also included 2 pigmented purpuric dermatoses (PPDs): progressive pigmentary purpura (Schamberg disease) and purpura annularis telangiectodes (Majocchi disease). Progressive pigmentary purpura is the most common manifestation of PPD and appears as cayenne pepper–colored macules that coalesce into golden brown–pigmented patches on the legs.⁹ Purpura annularis telangiectodes is another variant of PPD that manifests as pinpoint telangiectatic macules that progress to annular hyperpigmented patches with central clearing. Although PPDs frequently occur on the lower extremities, reports of plantar involvement are rare.¹⁰ Annular lichen planus manifests as violaceous papules with a clear center; however, it would be atypical for these lesions to be restricted to the feet and ankles. Palmoplantar lichen planus can mimic secondary syphilis clinically, but these cases manifest as hyperkeratotic pruritic papules on the palms and soles in contrast to the faint brown asymptomatic macules noted in our case.¹¹

Our case highlights an unusual presentation of secondary syphilis and demonstrates the challenge of diagnosing this entity on clinical presentation alone. Because this patient lacked the classic clinical and histopathologic features of secondary syphilis, a skin biopsy with positive immunohistochemical staining for treponemal antigens was necessary to make the diagnosis. Given the variability in presentation of secondary syphilis, a biopsy or serologic testing may be necessary to make a proper diagnosis.

THE DIAGNOSIS: Secondary Syphilis

Histopathology demonstrated a mild superficial perivascular and interstitial infiltrate composed of lymphocytes, histiocytes, and rare plasma cells with a background of extravasated erythrocytes (Figure, A). Treponema pallidum staining highlighted multiple spirochetes along the dermoepidermal junction and in the superficial dermis (Figure, B). Direct immunofluorescence was negative. Laboratory workup revealed a reactive rapid plasma reagin screen with a titer of 1:16 and positive IgG and IgM treponemal antibodies. The patient was diagnosed with secondary syphilis and was treated with a single dose of 2.4 million U of intramuscular benzathine penicillin G, with notable improvement of the rash and arthritis symptoms at 2-week follow-up.

Syphilis is a sexually transmitted infection caused by the spirochete T pallidum that progresses through active and latent stages. The incidence of both the primary and secondary stages of syphilis was at a historic low in the year 2000 and has increased annually since then.¹ Syphilis is more common in men, and men who have sex with men (MSM) are disproportionately affected. Although the incidence of syphilis in MSM has increased since 2000, rates have slowed, with slight decreases in this population between 2019 and 2020.¹ Conversely, rates among women have increased substantially in recent years, suggesting a more recent epidemic affecting heterosexual men and women.²

Classically, the primary stage of syphilis manifests as an asymptomatic papule followed by a painless ulcer (chancre) that heals spontaneously. The secondary stage of syphilis results from dissemination of T pallidum and is characterized by a wide range of mucocutaneous manifestations and prodromal symptoms. The most common cutaneous manifestation is a diffuse, nonpruritic, papulosquamous rash with red-brown scaly macules or papules on the trunk and extremities.³ The palms and soles commonly are involved. Mucosal patches, “snail-track” ulcers in the mouth, and condylomata lata are the characteristic mucosal lesions of secondary syphilis. Mucocutaneous findings typically are preceded by systemic signs including fever, malaise, myalgia, and generalized lymphadenopathy. However, syphilis is considered “the great mimicker,” with new reports of unusual presentations of the disease. In addition to papulosquamous morphologies, pustular, targetoid, psoriasiform, and noduloulcerative (also known as lues maligna) forms of syphilis have been reported.^3-5

The histopathologic features of secondary syphilis also are variable. Classically, secondary syphilis demonstrates vacuolar interface dermatitis and acanthosis with slender elongated rete ridges. Other well-known features include endothelial swelling and the presence of plasma cells in most cases.⁶ However, the histopathologic features of secondary syphilis may vary depending on the morphology of the skin eruption and when the biopsy is taken. Our patient lacked the classic histopathologic features of secondary syphilis. However, because syphilis was in the clinical differential diagnosis, a treponemal stain was ordered and confirmed the diagnosis. Immunohistochemical stains using antibodies to treponemal antigens have a reported sensitivity of 71% to 100% and are highly specific.⁷ Although the combination of endothelial swelling, interstitial inflammation, irregular acanthosis, and elongated rete ridges should raise the possibility of syphilis, a treponemal stain may be useful to identify spirochetes if clinical suspicion exists.⁸

Given our patient’s known history of GPA, leukocytoclastic vasculitis was high on the list of differential diagnoses. However, leukocytoclastic vasculitis most classically manifests as petechiae and palpable purpura, and unlike in secondary syphilis, the palms and soles are less commonly involved. Because our patient’s rash was mainly localized to the lower limbs, the differential also included 2 pigmented purpuric dermatoses (PPDs): progressive pigmentary purpura (Schamberg disease) and purpura annularis telangiectodes (Majocchi disease). Progressive pigmentary purpura is the most common manifestation of PPD and appears as cayenne pepper–colored macules that coalesce into golden brown–pigmented patches on the legs.⁹ Purpura annularis telangiectodes is another variant of PPD that manifests as pinpoint telangiectatic macules that progress to annular hyperpigmented patches with central clearing. Although PPDs frequently occur on the lower extremities, reports of plantar involvement are rare.¹⁰ Annular lichen planus manifests as violaceous papules with a clear center; however, it would be atypical for these lesions to be restricted to the feet and ankles. Palmoplantar lichen planus can mimic secondary syphilis clinically, but these cases manifest as hyperkeratotic pruritic papules on the palms and soles in contrast to the faint brown asymptomatic macules noted in our case.¹¹

Our case highlights an unusual presentation of secondary syphilis and demonstrates the challenge of diagnosing this entity on clinical presentation alone. Because this patient lacked the classic clinical and histopathologic features of secondary syphilis, a skin biopsy with positive immunohistochemical staining for treponemal antigens was necessary to make the diagnosis. Given the variability in presentation of secondary syphilis, a biopsy or serologic testing may be necessary to make a proper diagnosis.

To the Editor:

Kratom (Mitragyna speciosa) is an evergreen tree native to Southeast Asia.¹ Its leaves contain psychoactive compounds including mitragynine and 7-­hydroxymitragynine, which exert dose-dependent effects on the central nervous system through opioid and monoaminergic receptors.^2,3 At low doses (1–5 g), kratom elicits mild stimulant effects such as increased sociability, alertness, and talkativeness. At high doses (5–15 g), kratom has depressant effects that can provide relief from pain and opioid-withdrawal symptoms.³

Traditionally, kratom has been used in Southeast Asia for recreational and ceremonial purposes, to ease opioid-withdrawal symptoms, and to reduce fatigue from manual labor.⁴ In the 21st century, availability of kratom expanded to Europe, Australia, and the United States, largely facilitated by widespread dissemination of deceitful ­marketing and unregulated sales on the internet.¹ Although large-scale epidemiologic studies evaluating kratom’s prevalence are scarce, available evidence indicates rising worldwide usage, with a notable increase in kratom-related poison center calls between 2011 and 2017 in the United States.⁵ In July 2023, kratom made headlines due to the death of a woman in Florida following use of the substance.⁶

A cross-sectional study revealed that in the United States, kratom typically is used by White individuals for self-treatment of anxiety, depression, pain, and opioid withdrawal.⁷ However, the potential for severe adverse effects and dependence on kratom can outweigh the benefits.^6,8 Reported adverse effects of kratom include tachycardia, hypercholesteremia, liver injury, hallucinations, respiratory depression, seizure, coma, and death.^9,10 We present a case of kratom-induced photodistributed hyperpigmentation.

A 63-year-old man presented to the dermatology clinic with diffuse tender, pruritic, hyperpigmented skin lesions that developed over the course of 1 year. The lesions were distributed on sun-exposed areas, including the face, neck, and forearms (Figure 1). The patient reported no other major symptoms, and his health was otherwise unremarkable. He had a medical history of psoriasiform and spongiotic dermatitis consistent with eczema, psoriasis, hypercholesteremia, and hyperlipidemia. The patient was not taking any medications at the time of presentation. He had a family history of plaque psoriasis in his father. Five years prior to the current presentation, the patient was treated with adalimumab for steroid-resistant psoriasis; however, despite initial improvement, he experienced recurrence of scaly erythematous plaques and had discontinued adalimumab the year prior to presentation.

To the Editor:

Kratom (Mitragyna speciosa) is an evergreen tree native to Southeast Asia.¹ Its leaves contain psychoactive compounds including mitragynine and 7-­hydroxymitragynine, which exert dose-dependent effects on the central nervous system through opioid and monoaminergic receptors.^2,3 At low doses (1–5 g), kratom elicits mild stimulant effects such as increased sociability, alertness, and talkativeness. At high doses (5–15 g), kratom has depressant effects that can provide relief from pain and opioid-withdrawal symptoms.³

Traditionally, kratom has been used in Southeast Asia for recreational and ceremonial purposes, to ease opioid-withdrawal symptoms, and to reduce fatigue from manual labor.⁴ In the 21st century, availability of kratom expanded to Europe, Australia, and the United States, largely facilitated by widespread dissemination of deceitful ­marketing and unregulated sales on the internet.¹ Although large-scale epidemiologic studies evaluating kratom’s prevalence are scarce, available evidence indicates rising worldwide usage, with a notable increase in kratom-related poison center calls between 2011 and 2017 in the United States.⁵ In July 2023, kratom made headlines due to the death of a woman in Florida following use of the substance.⁶

A cross-sectional study revealed that in the United States, kratom typically is used by White individuals for self-treatment of anxiety, depression, pain, and opioid withdrawal.⁷ However, the potential for severe adverse effects and dependence on kratom can outweigh the benefits.^6,8 Reported adverse effects of kratom include tachycardia, hypercholesteremia, liver injury, hallucinations, respiratory depression, seizure, coma, and death.^9,10 We present a case of kratom-induced photodistributed hyperpigmentation.

A 63-year-old man presented to the dermatology clinic with diffuse tender, pruritic, hyperpigmented skin lesions that developed over the course of 1 year. The lesions were distributed on sun-exposed areas, including the face, neck, and forearms (Figure 1). The patient reported no other major symptoms, and his health was otherwise unremarkable. He had a medical history of psoriasiform and spongiotic dermatitis consistent with eczema, psoriasis, hypercholesteremia, and hyperlipidemia. The patient was not taking any medications at the time of presentation. He had a family history of plaque psoriasis in his father. Five years prior to the current presentation, the patient was treated with adalimumab for steroid-resistant psoriasis; however, despite initial improvement, he experienced recurrence of scaly erythematous plaques and had discontinued adalimumab the year prior to presentation.

To the Editor:

Kratom (Mitragyna speciosa) is an evergreen tree native to Southeast Asia.¹ Its leaves contain psychoactive compounds including mitragynine and 7-­hydroxymitragynine, which exert dose-dependent effects on the central nervous system through opioid and monoaminergic receptors.^2,3 At low doses (1–5 g), kratom elicits mild stimulant effects such as increased sociability, alertness, and talkativeness. At high doses (5–15 g), kratom has depressant effects that can provide relief from pain and opioid-withdrawal symptoms.³

Traditionally, kratom has been used in Southeast Asia for recreational and ceremonial purposes, to ease opioid-withdrawal symptoms, and to reduce fatigue from manual labor.⁴ In the 21st century, availability of kratom expanded to Europe, Australia, and the United States, largely facilitated by widespread dissemination of deceitful ­marketing and unregulated sales on the internet.¹ Although large-scale epidemiologic studies evaluating kratom’s prevalence are scarce, available evidence indicates rising worldwide usage, with a notable increase in kratom-related poison center calls between 2011 and 2017 in the United States.⁵ In July 2023, kratom made headlines due to the death of a woman in Florida following use of the substance.⁶

A cross-sectional study revealed that in the United States, kratom typically is used by White individuals for self-treatment of anxiety, depression, pain, and opioid withdrawal.⁷ However, the potential for severe adverse effects and dependence on kratom can outweigh the benefits.^6,8 Reported adverse effects of kratom include tachycardia, hypercholesteremia, liver injury, hallucinations, respiratory depression, seizure, coma, and death.^9,10 We present a case of kratom-induced photodistributed hyperpigmentation.

A 63-year-old man presented to the dermatology clinic with diffuse tender, pruritic, hyperpigmented skin lesions that developed over the course of 1 year. The lesions were distributed on sun-exposed areas, including the face, neck, and forearms (Figure 1). The patient reported no other major symptoms, and his health was otherwise unremarkable. He had a medical history of psoriasiform and spongiotic dermatitis consistent with eczema, psoriasis, hypercholesteremia, and hyperlipidemia. The patient was not taking any medications at the time of presentation. He had a family history of plaque psoriasis in his father. Five years prior to the current presentation, the patient was treated with adalimumab for steroid-resistant psoriasis; however, despite initial improvement, he experienced recurrence of scaly erythematous plaques and had discontinued adalimumab the year prior to presentation.

Vitiligo, the most common skin pigmentation disorder, has affected patients for thousands of years.¹ The psychological and social impacts on patients include sleep and sexual disorders, low self-esteem, low quality of life, anxiety, and depression when compared to those without vitiligo.^2,3 There have been substantial therapeutic advancements in the treatment of vitiligo, with the recent approval of ruxolitinib cream 1.5% by the US Food and Drug Administration (FDA) in 2022 and by the European Medicines Agency in 2023.⁴ Ruxolitinib is the first topical Janus kinase (JAK) inhibitor approved by the FDA for the treatment of nonsegmental vitiligo in patients 12 years and older, ushering in the era of JAK inhibitors for patients affected by vitiligo. The efficacy and safety of ruxolitinib was supported by 2 randomized clinical trials.⁴ It also is FDA approved for the intermittent and short-term treatment of mild to moderate atopic dermatitis in nonimmunocompromised patients 12 years and older whose disease is not adequately controlled with other topical medications.⁵

Vitiligo is characterized by an important inflammatory component, with the JAK/STAT (signal transducer and activator of transcription) pathway playing a crucial role in transmitting signals of inflammatory cytokines. In particular, IFN-γ and chemokines CXCL9 and CXCL10 are major contributors to the development of vitiligo, acting through the JAK/STAT pathway in local keratinocytes. Inhibiting JAK activity helps mitigate the effects of IFN-γ and downstream chemokines.⁶

Currently, baricitinib is not FDA approved for the treatment of vitiligo; it is FDA approved for moderate to severe active rheumatoid arthritis, severe alopecia areata, and in specific cases for COVID-19.⁷ Mumford et al⁸ first reported the use of oral baricitinib for the treatment of nonsegmental vitiligo. This patient experienced poor improvement using the oral JAK inhibitor tofacitinib for 5 months but achieved near-complete repigmentation after switching to baricitinib for 8 months (4 mg daily).⁸ Furthermore, a recent study found that in vitro baricitinib could increase tyrosinase activity and melanin content as well as stimulate the expression of genes related to tyrosinase in damaged melanocytes.⁹

A recent study by Li et al¹⁰ has shown satisfactory repigmentation and good tolerance in 2 cases of vitiligo treated with oral baricitinib in combination with narrowband UVB (NB-UVB) phototherapy. These findings are supported by a prior study of oral tofacitinib and NB-UVB phototherapy in 10 cases; the JAK inhibitor treatment demonstrated enhanced effectiveness when combined with light exposure.¹¹

Large-scale randomized clinical trials are needed to evaluate the efficacy and safety of oral baricitinib for vitiligo treatment. Currently, a clinical trial is underway (recruiting phase) to compare the efficacy and safety of combining baricitinib and excimer lamp phototherapy vs phototherapy alone.¹² The results of this trial can provide valuable information about whether baricitinib is promising as part of the therapeutic arsenal for vitiligo treatment in the future. A recently completed multicenter, randomized, double-blind clinical trial assessed the efficacy and tolerability of oral baricitinib in combination with NB-UVB phototherapy for the treatment of vitiligo. The trial included 49 patients and may provide valuable insights for the potential future application of baricitinib in the treatment of vitiligo.¹³ If the results of these clinical trials are favorable, approval of the first orally administered JAK inhibitor for repigmentation treatment in patients with vitiligo could follow, which would be a major breakthrough.

The off-label use of baricitinib—alone or in combination with phototherapy—appears to be promising in studies with a small sample size (an important limitation). The results of clinical trials will help us elucidate the efficacy and safety of baricitinib for vitiligo treatment, which could be a subject of debate. Recently, the FDA issued a warning due to findings showing that the use of tofacitinib has been associated with an increased risk of serious heart-related events, such heart attack, stroke, cancer, blood clots, and death.¹⁴ In response, the FDA issued warnings for 2 other JAK inhibitors—baricitinib and upadacitinib. Unlike tofacitinib, baricitinib and upadacitinib have not been studied in large safety clinical trials, and as a result, their risks have not been adequately evaluated. However, due to the shared mechanisms of action of these drugs, the FDA believes that these medications may pose similar risks as those observed in the tofacitinib safety trial.¹⁴

Disadvantages of JAK inhibitors include the high cost, immune-related side effects, potential cardiovascular adverse effects, and limited availability worldwide. If current and future clinical trials obtain objective evidence with a large sample size that yields positive outcomes with tolerable or acceptable side effects, and if the drug is affordable for hospitals and patients, the use of oral or topical baricitinib will be embraced and may be approved for vitiligo.

Vitiligo, the most common skin pigmentation disorder, has affected patients for thousands of years.¹ The psychological and social impacts on patients include sleep and sexual disorders, low self-esteem, low quality of life, anxiety, and depression when compared to those without vitiligo.^2,3 There have been substantial therapeutic advancements in the treatment of vitiligo, with the recent approval of ruxolitinib cream 1.5% by the US Food and Drug Administration (FDA) in 2022 and by the European Medicines Agency in 2023.⁴ Ruxolitinib is the first topical Janus kinase (JAK) inhibitor approved by the FDA for the treatment of nonsegmental vitiligo in patients 12 years and older, ushering in the era of JAK inhibitors for patients affected by vitiligo. The efficacy and safety of ruxolitinib was supported by 2 randomized clinical trials.⁴ It also is FDA approved for the intermittent and short-term treatment of mild to moderate atopic dermatitis in nonimmunocompromised patients 12 years and older whose disease is not adequately controlled with other topical medications.⁵

Vitiligo is characterized by an important inflammatory component, with the JAK/STAT (signal transducer and activator of transcription) pathway playing a crucial role in transmitting signals of inflammatory cytokines. In particular, IFN-γ and chemokines CXCL9 and CXCL10 are major contributors to the development of vitiligo, acting through the JAK/STAT pathway in local keratinocytes. Inhibiting JAK activity helps mitigate the effects of IFN-γ and downstream chemokines.⁶

Currently, baricitinib is not FDA approved for the treatment of vitiligo; it is FDA approved for moderate to severe active rheumatoid arthritis, severe alopecia areata, and in specific cases for COVID-19.⁷ Mumford et al⁸ first reported the use of oral baricitinib for the treatment of nonsegmental vitiligo. This patient experienced poor improvement using the oral JAK inhibitor tofacitinib for 5 months but achieved near-complete repigmentation after switching to baricitinib for 8 months (4 mg daily).⁸ Furthermore, a recent study found that in vitro baricitinib could increase tyrosinase activity and melanin content as well as stimulate the expression of genes related to tyrosinase in damaged melanocytes.⁹

A recent study by Li et al¹⁰ has shown satisfactory repigmentation and good tolerance in 2 cases of vitiligo treated with oral baricitinib in combination with narrowband UVB (NB-UVB) phototherapy. These findings are supported by a prior study of oral tofacitinib and NB-UVB phototherapy in 10 cases; the JAK inhibitor treatment demonstrated enhanced effectiveness when combined with light exposure.¹¹

Large-scale randomized clinical trials are needed to evaluate the efficacy and safety of oral baricitinib for vitiligo treatment. Currently, a clinical trial is underway (recruiting phase) to compare the efficacy and safety of combining baricitinib and excimer lamp phototherapy vs phototherapy alone.¹² The results of this trial can provide valuable information about whether baricitinib is promising as part of the therapeutic arsenal for vitiligo treatment in the future. A recently completed multicenter, randomized, double-blind clinical trial assessed the efficacy and tolerability of oral baricitinib in combination with NB-UVB phototherapy for the treatment of vitiligo. The trial included 49 patients and may provide valuable insights for the potential future application of baricitinib in the treatment of vitiligo.¹³ If the results of these clinical trials are favorable, approval of the first orally administered JAK inhibitor for repigmentation treatment in patients with vitiligo could follow, which would be a major breakthrough.

The off-label use of baricitinib—alone or in combination with phototherapy—appears to be promising in studies with a small sample size (an important limitation). The results of clinical trials will help us elucidate the efficacy and safety of baricitinib for vitiligo treatment, which could be a subject of debate. Recently, the FDA issued a warning due to findings showing that the use of tofacitinib has been associated with an increased risk of serious heart-related events, such heart attack, stroke, cancer, blood clots, and death.¹⁴ In response, the FDA issued warnings for 2 other JAK inhibitors—baricitinib and upadacitinib. Unlike tofacitinib, baricitinib and upadacitinib have not been studied in large safety clinical trials, and as a result, their risks have not been adequately evaluated. However, due to the shared mechanisms of action of these drugs, the FDA believes that these medications may pose similar risks as those observed in the tofacitinib safety trial.¹⁴

Disadvantages of JAK inhibitors include the high cost, immune-related side effects, potential cardiovascular adverse effects, and limited availability worldwide. If current and future clinical trials obtain objective evidence with a large sample size that yields positive outcomes with tolerable or acceptable side effects, and if the drug is affordable for hospitals and patients, the use of oral or topical baricitinib will be embraced and may be approved for vitiligo.

Vitiligo, the most common skin pigmentation disorder, has affected patients for thousands of years.¹ The psychological and social impacts on patients include sleep and sexual disorders, low self-esteem, low quality of life, anxiety, and depression when compared to those without vitiligo.^2,3 There have been substantial therapeutic advancements in the treatment of vitiligo, with the recent approval of ruxolitinib cream 1.5% by the US Food and Drug Administration (FDA) in 2022 and by the European Medicines Agency in 2023.⁴ Ruxolitinib is the first topical Janus kinase (JAK) inhibitor approved by the FDA for the treatment of nonsegmental vitiligo in patients 12 years and older, ushering in the era of JAK inhibitors for patients affected by vitiligo. The efficacy and safety of ruxolitinib was supported by 2 randomized clinical trials.⁴ It also is FDA approved for the intermittent and short-term treatment of mild to moderate atopic dermatitis in nonimmunocompromised patients 12 years and older whose disease is not adequately controlled with other topical medications.⁵

Vitiligo is characterized by an important inflammatory component, with the JAK/STAT (signal transducer and activator of transcription) pathway playing a crucial role in transmitting signals of inflammatory cytokines. In particular, IFN-γ and chemokines CXCL9 and CXCL10 are major contributors to the development of vitiligo, acting through the JAK/STAT pathway in local keratinocytes. Inhibiting JAK activity helps mitigate the effects of IFN-γ and downstream chemokines.⁶

Currently, baricitinib is not FDA approved for the treatment of vitiligo; it is FDA approved for moderate to severe active rheumatoid arthritis, severe alopecia areata, and in specific cases for COVID-19.⁷ Mumford et al⁸ first reported the use of oral baricitinib for the treatment of nonsegmental vitiligo. This patient experienced poor improvement using the oral JAK inhibitor tofacitinib for 5 months but achieved near-complete repigmentation after switching to baricitinib for 8 months (4 mg daily).⁸ Furthermore, a recent study found that in vitro baricitinib could increase tyrosinase activity and melanin content as well as stimulate the expression of genes related to tyrosinase in damaged melanocytes.⁹

A recent study by Li et al¹⁰ has shown satisfactory repigmentation and good tolerance in 2 cases of vitiligo treated with oral baricitinib in combination with narrowband UVB (NB-UVB) phototherapy. These findings are supported by a prior study of oral tofacitinib and NB-UVB phototherapy in 10 cases; the JAK inhibitor treatment demonstrated enhanced effectiveness when combined with light exposure.¹¹

Large-scale randomized clinical trials are needed to evaluate the efficacy and safety of oral baricitinib for vitiligo treatment. Currently, a clinical trial is underway (recruiting phase) to compare the efficacy and safety of combining baricitinib and excimer lamp phototherapy vs phototherapy alone.¹² The results of this trial can provide valuable information about whether baricitinib is promising as part of the therapeutic arsenal for vitiligo treatment in the future. A recently completed multicenter, randomized, double-blind clinical trial assessed the efficacy and tolerability of oral baricitinib in combination with NB-UVB phototherapy for the treatment of vitiligo. The trial included 49 patients and may provide valuable insights for the potential future application of baricitinib in the treatment of vitiligo.¹³ If the results of these clinical trials are favorable, approval of the first orally administered JAK inhibitor for repigmentation treatment in patients with vitiligo could follow, which would be a major breakthrough.

The off-label use of baricitinib—alone or in combination with phototherapy—appears to be promising in studies with a small sample size (an important limitation). The results of clinical trials will help us elucidate the efficacy and safety of baricitinib for vitiligo treatment, which could be a subject of debate. Recently, the FDA issued a warning due to findings showing that the use of tofacitinib has been associated with an increased risk of serious heart-related events, such heart attack, stroke, cancer, blood clots, and death.¹⁴ In response, the FDA issued warnings for 2 other JAK inhibitors—baricitinib and upadacitinib. Unlike tofacitinib, baricitinib and upadacitinib have not been studied in large safety clinical trials, and as a result, their risks have not been adequately evaluated. However, due to the shared mechanisms of action of these drugs, the FDA believes that these medications may pose similar risks as those observed in the tofacitinib safety trial.¹⁴

Disadvantages of JAK inhibitors include the high cost, immune-related side effects, potential cardiovascular adverse effects, and limited availability worldwide. If current and future clinical trials obtain objective evidence with a large sample size that yields positive outcomes with tolerable or acceptable side effects, and if the drug is affordable for hospitals and patients, the use of oral or topical baricitinib will be embraced and may be approved for vitiligo.

Practice Gap

Lichen planus (LP) is an inflammatory cutaneous disorder. Although it often is characterized by the 6 Ps—pruritic, polygonal, planar, purple, papules, and plaques with a predilection for the wrists and ankles—the presentation can vary in morphology and distribution.^1-5 With an incidence of approximately 1% in the general population, LP is undoubtedly uncommon.¹ Its prevalence in the pediatric population is especially low, with only 2% to 3% of cases manifesting in individuals younger than 20 years.²

Generalized LP (also referred to as eruptive or exanthematous LP) is a rarely reported clinical subtype in which lesions are disseminated or spread rapidly.⁵ The rarity of generalized LP in children often leads to misdiagnosis or delayed treatment, impacting the patient’s quality of life. Thus, there is a need for heightened awareness among clinicians on the variable presentation of LP in the pediatric population. Incorporating a punch biopsy for the diagnosis of LP when lesions manifest as widespread, erythematous to violaceous, flat-topped papules or plaques, along with the addition of an intramuscular (IM) injection in the treatment plan, improves overall patient outcomes.

Tools and Techniques

A detailed physical examination followed by a punch biopsy was critical for the diagnosis of generalized LP in a 7-year-old Black girl. The examination revealed a widespread distribution of dark, violaceous, polygonal, shiny, flat-topped, firm papules coalescing into plaques across the entire body, with a greater predilection for the legs and overlying joints (Figure, A). Some lesions exhibited fine, silver-white, reticular patterns consistent with Wickham striae. Notably, there was no involvement of the scalp, nails, or mucosal surfaces.

The patient had no relevant medical or family history of skin disease and no recent history of illness. She previously was treated by a pediatrician with triamcinolone cream 0.1%, a course of oral cephalexin, and oral cetirizine 10 mg once daily without relief of symptoms.

Although the clinical presentation was consistent with LP, the differential diagnosis included lichen simplex chronicus, atopic dermatitis, psoriasis, and generalized granuloma annulare. To address the need for early recognition of LP in pediatric patients, a punch biopsy of a lesion on the left anterior thigh was performed and showed lichenoid interface dermatitis—a pivotal finding in distinguishing LP from other conditions in the differential.

Given the patient’s age and severity of the LP, a combination of topical and systemic therapies was prescribed—clobetasol cream 0.025% twice daily and 1 injection of 0.5 cc of IM triamcinolone acetonide 40 mg/mL. This regimen was guided by the efficacy of IM injections in providing prompt symptomatic relief, particularly for patients with extensive disease or for those whose condition is refractory to topical treatments.⁶ Our patient achieved remarkable improvement at 2-week ­follow-up (Figure, B), without any observed adverse effects. At that time, the patient’s mother refused further systemic treatment and opted for only the topical therapy as well as natural light therapy.

Practice Implications

Timely and accurate diagnosis of LP in pediatric patients, especially those with skin of color, is crucial. Early intervention is especially important in mitigating the risk for chronic symptoms and preventing potential scarring, which tends to be more pronounced and challenging to treat in individuals with darker skin tones.⁷ Although not present in our patient, it is important to note that LP can affect the face (including the eyelids) as well as the palms and soles in pediatric patients with skin of color.

The most common approach to management of pediatric LP involves the use of a topical corticosteroid and an oral antihistamine, but the recalcitrant and generalized distribution of lesions warrants the administration of a systemic corticosteroid regardless of the patient’s age.⁶ In our patient, prompt administration of low-dose IM triamcinolone was both crucial and beneficial. Although an underutilized approach, IM triamcinolone helps to prevent the progression of lesions to the scalp, nails, and mucosa while also reducing inflammation and pruritus in glabrous skin.⁸

Triamcinolone acetonide injections—­administered at concentrations of 5 to 40 mg/mL—directly into the lesion (0.5–1 cc per 2 cm²) are highly effective in managing recalcitrant thickened lesions such as those seen in hypertrophic LP and palmoplantar LP.⁶ This treatment is particularly beneficial when lesions are unresponsive to topical therapies. Administered every 3 to 6 weeks, these injections provide rapid symptom relief, typically within 72 hours,⁶ while also contributing to the reduction of lesion size and thickness over time. The concentration of triamcinolone acetonide should be selected based on the lesion’s severity, with higher concentrations reserved for thicker, more resistant lesions. More frequent injections may be warranted in cases in which rapid lesion reduction is necessary, while less frequent sessions may suffice for maintenance therapy. It is important to follow patients closely for adverse effects, such as signs of local skin atrophy or hypopigmentation, and to adjust the dose or frequency accordingly. To mitigate these risks, consider using the lowest effective concentration and rotating injection sites if treating multiple lesions. Additionally, combining intralesional corticosteroids with topical therapies can enhance outcomes, particularly in cases in which monotherapy is insufficient.

Patients should be monitored vigilantly for complications of LP. The risk for postinflammatory hyperpigmentation is a particular concern for patients with skin of color. Other complications of untreated LP include nail deformities and scarring alopecia.⁹ Regular and thorough follow-ups every few months to monitor scalp, mucosal, and genital involvement are essential to manage this risk effectively.

Furthermore, patient education is key. Informing patients and their caregivers about the nature of LP, the available treatment options, and the importance of ongoing follow-up can help to enhance treatment adherence and improve overall outcomes.

Practice Gap

Lichen planus (LP) is an inflammatory cutaneous disorder. Although it often is characterized by the 6 Ps—pruritic, polygonal, planar, purple, papules, and plaques with a predilection for the wrists and ankles—the presentation can vary in morphology and distribution.^1-5 With an incidence of approximately 1% in the general population, LP is undoubtedly uncommon.¹ Its prevalence in the pediatric population is especially low, with only 2% to 3% of cases manifesting in individuals younger than 20 years.²

Generalized LP (also referred to as eruptive or exanthematous LP) is a rarely reported clinical subtype in which lesions are disseminated or spread rapidly.⁵ The rarity of generalized LP in children often leads to misdiagnosis or delayed treatment, impacting the patient’s quality of life. Thus, there is a need for heightened awareness among clinicians on the variable presentation of LP in the pediatric population. Incorporating a punch biopsy for the diagnosis of LP when lesions manifest as widespread, erythematous to violaceous, flat-topped papules or plaques, along with the addition of an intramuscular (IM) injection in the treatment plan, improves overall patient outcomes.

Tools and Techniques

A detailed physical examination followed by a punch biopsy was critical for the diagnosis of generalized LP in a 7-year-old Black girl. The examination revealed a widespread distribution of dark, violaceous, polygonal, shiny, flat-topped, firm papules coalescing into plaques across the entire body, with a greater predilection for the legs and overlying joints (Figure, A). Some lesions exhibited fine, silver-white, reticular patterns consistent with Wickham striae. Notably, there was no involvement of the scalp, nails, or mucosal surfaces.

The patient had no relevant medical or family history of skin disease and no recent history of illness. She previously was treated by a pediatrician with triamcinolone cream 0.1%, a course of oral cephalexin, and oral cetirizine 10 mg once daily without relief of symptoms.

Although the clinical presentation was consistent with LP, the differential diagnosis included lichen simplex chronicus, atopic dermatitis, psoriasis, and generalized granuloma annulare. To address the need for early recognition of LP in pediatric patients, a punch biopsy of a lesion on the left anterior thigh was performed and showed lichenoid interface dermatitis—a pivotal finding in distinguishing LP from other conditions in the differential.

Given the patient’s age and severity of the LP, a combination of topical and systemic therapies was prescribed—clobetasol cream 0.025% twice daily and 1 injection of 0.5 cc of IM triamcinolone acetonide 40 mg/mL. This regimen was guided by the efficacy of IM injections in providing prompt symptomatic relief, particularly for patients with extensive disease or for those whose condition is refractory to topical treatments.⁶ Our patient achieved remarkable improvement at 2-week ­follow-up (Figure, B), without any observed adverse effects. At that time, the patient’s mother refused further systemic treatment and opted for only the topical therapy as well as natural light therapy.

Practice Implications

Timely and accurate diagnosis of LP in pediatric patients, especially those with skin of color, is crucial. Early intervention is especially important in mitigating the risk for chronic symptoms and preventing potential scarring, which tends to be more pronounced and challenging to treat in individuals with darker skin tones.⁷ Although not present in our patient, it is important to note that LP can affect the face (including the eyelids) as well as the palms and soles in pediatric patients with skin of color.

The most common approach to management of pediatric LP involves the use of a topical corticosteroid and an oral antihistamine, but the recalcitrant and generalized distribution of lesions warrants the administration of a systemic corticosteroid regardless of the patient’s age.⁶ In our patient, prompt administration of low-dose IM triamcinolone was both crucial and beneficial. Although an underutilized approach, IM triamcinolone helps to prevent the progression of lesions to the scalp, nails, and mucosa while also reducing inflammation and pruritus in glabrous skin.⁸

Triamcinolone acetonide injections—­administered at concentrations of 5 to 40 mg/mL—directly into the lesion (0.5–1 cc per 2 cm²) are highly effective in managing recalcitrant thickened lesions such as those seen in hypertrophic LP and palmoplantar LP.⁶ This treatment is particularly beneficial when lesions are unresponsive to topical therapies. Administered every 3 to 6 weeks, these injections provide rapid symptom relief, typically within 72 hours,⁶ while also contributing to the reduction of lesion size and thickness over time. The concentration of triamcinolone acetonide should be selected based on the lesion’s severity, with higher concentrations reserved for thicker, more resistant lesions. More frequent injections may be warranted in cases in which rapid lesion reduction is necessary, while less frequent sessions may suffice for maintenance therapy. It is important to follow patients closely for adverse effects, such as signs of local skin atrophy or hypopigmentation, and to adjust the dose or frequency accordingly. To mitigate these risks, consider using the lowest effective concentration and rotating injection sites if treating multiple lesions. Additionally, combining intralesional corticosteroids with topical therapies can enhance outcomes, particularly in cases in which monotherapy is insufficient.

Patients should be monitored vigilantly for complications of LP. The risk for postinflammatory hyperpigmentation is a particular concern for patients with skin of color. Other complications of untreated LP include nail deformities and scarring alopecia.⁹ Regular and thorough follow-ups every few months to monitor scalp, mucosal, and genital involvement are essential to manage this risk effectively.

Furthermore, patient education is key. Informing patients and their caregivers about the nature of LP, the available treatment options, and the importance of ongoing follow-up can help to enhance treatment adherence and improve overall outcomes.

Practice Gap

Lichen planus (LP) is an inflammatory cutaneous disorder. Although it often is characterized by the 6 Ps—pruritic, polygonal, planar, purple, papules, and plaques with a predilection for the wrists and ankles—the presentation can vary in morphology and distribution.^1-5 With an incidence of approximately 1% in the general population, LP is undoubtedly uncommon.¹ Its prevalence in the pediatric population is especially low, with only 2% to 3% of cases manifesting in individuals younger than 20 years.²

Generalized LP (also referred to as eruptive or exanthematous LP) is a rarely reported clinical subtype in which lesions are disseminated or spread rapidly.⁵ The rarity of generalized LP in children often leads to misdiagnosis or delayed treatment, impacting the patient’s quality of life. Thus, there is a need for heightened awareness among clinicians on the variable presentation of LP in the pediatric population. Incorporating a punch biopsy for the diagnosis of LP when lesions manifest as widespread, erythematous to violaceous, flat-topped papules or plaques, along with the addition of an intramuscular (IM) injection in the treatment plan, improves overall patient outcomes.

Tools and Techniques

A detailed physical examination followed by a punch biopsy was critical for the diagnosis of generalized LP in a 7-year-old Black girl. The examination revealed a widespread distribution of dark, violaceous, polygonal, shiny, flat-topped, firm papules coalescing into plaques across the entire body, with a greater predilection for the legs and overlying joints (Figure, A). Some lesions exhibited fine, silver-white, reticular patterns consistent with Wickham striae. Notably, there was no involvement of the scalp, nails, or mucosal surfaces.

The patient had no relevant medical or family history of skin disease and no recent history of illness. She previously was treated by a pediatrician with triamcinolone cream 0.1%, a course of oral cephalexin, and oral cetirizine 10 mg once daily without relief of symptoms.

Although the clinical presentation was consistent with LP, the differential diagnosis included lichen simplex chronicus, atopic dermatitis, psoriasis, and generalized granuloma annulare. To address the need for early recognition of LP in pediatric patients, a punch biopsy of a lesion on the left anterior thigh was performed and showed lichenoid interface dermatitis—a pivotal finding in distinguishing LP from other conditions in the differential.

Given the patient’s age and severity of the LP, a combination of topical and systemic therapies was prescribed—clobetasol cream 0.025% twice daily and 1 injection of 0.5 cc of IM triamcinolone acetonide 40 mg/mL. This regimen was guided by the efficacy of IM injections in providing prompt symptomatic relief, particularly for patients with extensive disease or for those whose condition is refractory to topical treatments.⁶ Our patient achieved remarkable improvement at 2-week ­follow-up (Figure, B), without any observed adverse effects. At that time, the patient’s mother refused further systemic treatment and opted for only the topical therapy as well as natural light therapy.

Practice Implications

Timely and accurate diagnosis of LP in pediatric patients, especially those with skin of color, is crucial. Early intervention is especially important in mitigating the risk for chronic symptoms and preventing potential scarring, which tends to be more pronounced and challenging to treat in individuals with darker skin tones.⁷ Although not present in our patient, it is important to note that LP can affect the face (including the eyelids) as well as the palms and soles in pediatric patients with skin of color.

The most common approach to management of pediatric LP involves the use of a topical corticosteroid and an oral antihistamine, but the recalcitrant and generalized distribution of lesions warrants the administration of a systemic corticosteroid regardless of the patient’s age.⁶ In our patient, prompt administration of low-dose IM triamcinolone was both crucial and beneficial. Although an underutilized approach, IM triamcinolone helps to prevent the progression of lesions to the scalp, nails, and mucosa while also reducing inflammation and pruritus in glabrous skin.⁸

Triamcinolone acetonide injections—­administered at concentrations of 5 to 40 mg/mL—directly into the lesion (0.5–1 cc per 2 cm²) are highly effective in managing recalcitrant thickened lesions such as those seen in hypertrophic LP and palmoplantar LP.⁶ This treatment is particularly beneficial when lesions are unresponsive to topical therapies. Administered every 3 to 6 weeks, these injections provide rapid symptom relief, typically within 72 hours,⁶ while also contributing to the reduction of lesion size and thickness over time. The concentration of triamcinolone acetonide should be selected based on the lesion’s severity, with higher concentrations reserved for thicker, more resistant lesions. More frequent injections may be warranted in cases in which rapid lesion reduction is necessary, while less frequent sessions may suffice for maintenance therapy. It is important to follow patients closely for adverse effects, such as signs of local skin atrophy or hypopigmentation, and to adjust the dose or frequency accordingly. To mitigate these risks, consider using the lowest effective concentration and rotating injection sites if treating multiple lesions. Additionally, combining intralesional corticosteroids with topical therapies can enhance outcomes, particularly in cases in which monotherapy is insufficient.

Patients should be monitored vigilantly for complications of LP. The risk for postinflammatory hyperpigmentation is a particular concern for patients with skin of color. Other complications of untreated LP include nail deformities and scarring alopecia.⁹ Regular and thorough follow-ups every few months to monitor scalp, mucosal, and genital involvement are essential to manage this risk effectively.

Furthermore, patient education is key. Informing patients and their caregivers about the nature of LP, the available treatment options, and the importance of ongoing follow-up can help to enhance treatment adherence and improve overall outcomes.

Diversity, equity, and inclusion (DEI) programs seek to improve dermatologic education and clinical care for an increasingly diverse patient population as well as to recruit and sustain a physician workforce that reflects the diversity of the patients they serve.^1,2 In dermatology, only 4.2% and 3.0% of practicing dermatologists self-identify as being of Hispanic and African American ethnicity, respectively, compared with 18.5% and 13.4% of the general population, respectively.³ Creating an educational system that works to meet the goals of DEI is essential to improve health outcomes and address disparities. The lack of robust DEI-related curricula during residency training may limit the ability of practicing dermatologists to provide comprehensive and culturally sensitive care. It has been shown that racial concordance between patients and physicians has a positive impact on patient satisfaction by fostering a trusting patient-physician relationship.⁴

It is the responsibility of all dermatologists to create an environment where patients from any background can feel comfortable, which can be cultivated by establishing patient-centered communication and cultural humility.⁵ These skills can be strengthened via the implementation of DEI-related curricula during residency training. Augmenting exposure of these topics during training can optimize the delivery of dermatologic care by providing residents with the tools and confidence needed to care for patients of culturally diverse backgrounds. Enhancing DEI education is crucial to not only improve the recognition and treatment of dermatologic conditions in all skin and hair types but also to minimize misconceptions, stigma, health disparities, and discrimination faced by historically marginalized communities. Creating a culture of inclusion is of paramount importance to build successful relationships with patients and colleagues of culturally diverse backgrounds.⁶

There are multiple efforts underway to increase DEI education across the field of dermatology, including the development of DEI task forces in professional organizations and societies that serve to expand DEI-related research, mentorship, and education. The American Academy of Dermatology has been leading efforts to create a curriculum focused on skin of color, particularly addressing inadequate educational training on how dermatologic conditions manifest in this population.⁷ The Skin of Color Society has similar efforts underway and is developing a speakers bureau to give leading experts a platform to lecture dermatology trainees as well as patient and community audiences on various topics in skin of color.⁸ These are just 2 of many professional dermatology organizations that are advocating for expanded education on DEI; however, consistently integrating DEI-related topics into dermatology residency training curricula remains a gap in pedagogy. To identify the DEI-related topics of greatest relevance to the dermatology resident curricula, we implemented a modified electronic Delphi (e-Delphi) consensus process to provide standardized recommendations.

Methods

A 2-round modified e-Delphi method was utilized (Figure). An initial list of potential curricular topics was formulated by an expert panel consisting of 5 dermatologists from the Association of Professors of Dermatology DEI subcommittee and the American Academy of Dermatology Diversity Task Force (A.M.A., S.B., R.V., S.D.W., J.I.S.). Initial topics were selected via several meetings among the panel members to discuss existing DEI concerns and issues that were deemed relevant due to education gaps in residency training. The list of topics was further expanded with recommendations obtained via an email sent to dermatology program directors on the Association of Professors of Dermatology listserve, which solicited voluntary participation of academic dermatologists, including program directors and dermatology residents.

There were 2 voting rounds, with each round consisting of questions scored on a Likert scale ranging from 1 to 5 (1=not essential, 2=probably not essential, 3=neutral, 4=probably essential, 5=definitely essential). The inclusion criteria to classify a topic as necessary for integration into the dermatology residency curriculum included 95% (18/19) or more of respondents rating the topic as probably essential or definitely essential; if more than 90% (17/19) of respondents rated the topic as probably essential or definitely essential and less than 10% (2/19) rated it as not essential or probably not essential, the topic was still included as part of the suggested curriculum. Topics that received ratings of probably essential or definitely essential by less than 80% (15/19) of respondents were removed from consideration. The topics that did not meet inclusion or exclusion criteria during the first round of voting were refined by the e-Delphi steering committee (V.S.E-C. and F-A.R.) based on open-ended feedback from the voting group provided at the end of the survey and subsequently passed to the second round of voting.

Results

Participants—A total of 19 respondents participated in both voting rounds, the majority (80% [15/19]) of whom were program directors or dermatologists affiliated with academia or development of DEI education; the remaining 20% [4/19]) were dermatology residents.

Open-Ended Feedback—Voting group members were able to provide open-ended feedback for each of the sets of topics after the survey, which the steering committee utilized to modify the topics as needed for the final voting round. For example, “structural racism/discrimination” was originally mentioned as a topic, but several participants suggested including specific types of racism; therefore, the wording was changed to “racism: types, definitions” to encompass broader definitions and types of racism.

Survey Results—Two genres of topics were surveyed in each voting round: clinical and nonclinical. Participants voted on a total of 61 topics, with 23 ultimately selected in the final list of consensus curricular topics. Of those, 9 were clinical and 14 nonclinical. All topics deemed necessary for inclusion in residency curricula are presented in eTables 1 and 2.

During the first round of voting, the e-Delphi panel reached a consensus to include the following 17 topics as essential to dermatology residency training (along with the percentage of voters who classified them as probably essential or definitely essential): how to mitigate bias in clinical and workplace settings (100% [40/40]); social determinants of health-related disparities in dermatology (100% [40/40]); hairstyling practices across different hair textures (100% [40/40]); definitions and examples of microaggressions (97.50% [39/40]); definition, background, and types of bias (97.50% [39/40]); manifestations of bias in the clinical setting (97.44% [38/39]); racial and ethnic disparities in dermatology (97.44% [38/39]); keloids (97.37% [37/38]); differences in dermoscopic presentations in skin of color (97.30% [36/37]); skin cancer in patients with skin of color (97.30% [36/37]); disparities due to bias (95.00% [38/40]); how to apply cultural humility and safety to patients of different cultural backgrounds (94.87% [37/40]); best practices in providing care to patients with limited English proficiency (94.87% [37/40]); hair loss in patients with textured hair (94.74% [36/38]); pseudofolliculitis barbae and acne keloidalis nuchae (94.60% [35/37]); disparities regarding people experiencing homelessness (92.31% [36/39]); and definitions and types of racism and other forms of discrimination (92.31% [36/39]). eTable 1 provides a list of suggested resources to incorporate these topics into the educational components of residency curricula. The resources provided were not part of the voting process, and they were not considered in the consensus analysis; they are included here as suggested educational catalysts.

During the second round of voting, 25 topics were evaluated. Of those, the following 6 topics were proposed to be included as essential in residency training: differences in prevalence and presentation of common inflammatory disorders (100% [29/29]); manifestations of bias in the learning environment (96.55%); antiracist action and how to decrease the effects of structural racism in clinical and educational settings (96.55% [28/29]); diversity of images in dermatology education (96.55% [28/29]); pigmentary disorders and their psychological effects (96.55% [28/29]); and LGBTQ (lesbian, gay, bisexual, transgender, and queer) dermatologic health care (96.55% [28/29]). eTable 2 includes these topics as well as suggested resources to help incorporate them into training.

Comment

This study utilized a modified e-Delphi technique to identify relevant clinical and nonclinical DEI topics that should be incorporated into dermatology residency curricula. The panel members reached a consensus for 9 clinical DEI-related topics. The respondents agreed that the topics related to skin and hair conditions in patients with skin of color as well as textured hair were crucial to residency education. Skin cancer, hair loss, pseudofolliculitis barbae, acne keloidalis nuchae, keloids, pigmentary disorders, and their varying presentations in patients with skin of color were among the recommended topics. The panel also recommended educating residents on the variable visual presentations of inflammatory conditions in skin of color. Addressing the needs of diverse patients—for example, those belonging to the LGBTQ community—also was deemed important for inclusion.

The remaining 14 chosen topics were nonclinical items addressing concepts such as bias and health care disparities as well as cultural humility and safety.⁹ Cultural humility and safety focus on developing cultural awareness by creating a safe setting for patients rather than encouraging power relationships between them and their physicians. Various topics related to racism also were recommended to be included in residency curricula, including education on implementation of antiracist action in the workplace.

Many of the nonclinical topics are intertwined; for instance, learning about health care disparities in patients with limited English proficiency allows for improved best practices in delivering care to patients from this population. The first step in overcoming bias and subsequent disparities is acknowledging how the perpetuation of bias leads to disparities after being taught tools to recognize it.

Our group’s guidance on DEI topics should help dermatology residency program leaders as they design and refine program curricula. There are multiple avenues for incorporating education on these topics, including lectures, interactive workshops, role-playing sessions, book or journal clubs, and discussion circles. Many of these topics/programs may already be included in programs’ didactic curricula, which would minimize the burden of finding space to educate on these topics. Institutional cultural change is key to ensuring truly diverse, equitable, and inclusive workplaces. Educating tomorrow’s dermatologists on these topics is a first step toward achieving that cultural change.

Limitations—A limitation of this e-Delphi survey is that only a selection of experts in this field was included. Additionally, we were concerned that the Likert scale format and the bar we set for inclusion and exclusion may have failed to adequately capture participants’ nuanced opinions. As such, participants were able to provide open-ended feedback, and suggestions for alternate wording or other changes were considered by the steering committee. Finally, inclusion recommendations identified in this survey were developed specifically for US dermatology residents.

Conclusion

In this e-Delphi consensus assessment of DEI-related topics, we recommend the inclusion of 23 topics into dermatology residency program curricula to improve medical training and the patient-physician relationship as well as to create better health outcomes. We also provide specific sample resource recommendations in eTables 1 and 2 to facilitate inclusion of these topics into residency curricula across the country.

Diversity, equity, and inclusion (DEI) programs seek to improve dermatologic education and clinical care for an increasingly diverse patient population as well as to recruit and sustain a physician workforce that reflects the diversity of the patients they serve.^1,2 In dermatology, only 4.2% and 3.0% of practicing dermatologists self-identify as being of Hispanic and African American ethnicity, respectively, compared with 18.5% and 13.4% of the general population, respectively.³ Creating an educational system that works to meet the goals of DEI is essential to improve health outcomes and address disparities. The lack of robust DEI-related curricula during residency training may limit the ability of practicing dermatologists to provide comprehensive and culturally sensitive care. It has been shown that racial concordance between patients and physicians has a positive impact on patient satisfaction by fostering a trusting patient-physician relationship.⁴

It is the responsibility of all dermatologists to create an environment where patients from any background can feel comfortable, which can be cultivated by establishing patient-centered communication and cultural humility.⁵ These skills can be strengthened via the implementation of DEI-related curricula during residency training. Augmenting exposure of these topics during training can optimize the delivery of dermatologic care by providing residents with the tools and confidence needed to care for patients of culturally diverse backgrounds. Enhancing DEI education is crucial to not only improve the recognition and treatment of dermatologic conditions in all skin and hair types but also to minimize misconceptions, stigma, health disparities, and discrimination faced by historically marginalized communities. Creating a culture of inclusion is of paramount importance to build successful relationships with patients and colleagues of culturally diverse backgrounds.⁶

There are multiple efforts underway to increase DEI education across the field of dermatology, including the development of DEI task forces in professional organizations and societies that serve to expand DEI-related research, mentorship, and education. The American Academy of Dermatology has been leading efforts to create a curriculum focused on skin of color, particularly addressing inadequate educational training on how dermatologic conditions manifest in this population.⁷ The Skin of Color Society has similar efforts underway and is developing a speakers bureau to give leading experts a platform to lecture dermatology trainees as well as patient and community audiences on various topics in skin of color.⁸ These are just 2 of many professional dermatology organizations that are advocating for expanded education on DEI; however, consistently integrating DEI-related topics into dermatology residency training curricula remains a gap in pedagogy. To identify the DEI-related topics of greatest relevance to the dermatology resident curricula, we implemented a modified electronic Delphi (e-Delphi) consensus process to provide standardized recommendations.

Methods

A 2-round modified e-Delphi method was utilized (Figure). An initial list of potential curricular topics was formulated by an expert panel consisting of 5 dermatologists from the Association of Professors of Dermatology DEI subcommittee and the American Academy of Dermatology Diversity Task Force (A.M.A., S.B., R.V., S.D.W., J.I.S.). Initial topics were selected via several meetings among the panel members to discuss existing DEI concerns and issues that were deemed relevant due to education gaps in residency training. The list of topics was further expanded with recommendations obtained via an email sent to dermatology program directors on the Association of Professors of Dermatology listserve, which solicited voluntary participation of academic dermatologists, including program directors and dermatology residents.

There were 2 voting rounds, with each round consisting of questions scored on a Likert scale ranging from 1 to 5 (1=not essential, 2=probably not essential, 3=neutral, 4=probably essential, 5=definitely essential). The inclusion criteria to classify a topic as necessary for integration into the dermatology residency curriculum included 95% (18/19) or more of respondents rating the topic as probably essential or definitely essential; if more than 90% (17/19) of respondents rated the topic as probably essential or definitely essential and less than 10% (2/19) rated it as not essential or probably not essential, the topic was still included as part of the suggested curriculum. Topics that received ratings of probably essential or definitely essential by less than 80% (15/19) of respondents were removed from consideration. The topics that did not meet inclusion or exclusion criteria during the first round of voting were refined by the e-Delphi steering committee (V.S.E-C. and F-A.R.) based on open-ended feedback from the voting group provided at the end of the survey and subsequently passed to the second round of voting.

Results

Participants—A total of 19 respondents participated in both voting rounds, the majority (80% [15/19]) of whom were program directors or dermatologists affiliated with academia or development of DEI education; the remaining 20% [4/19]) were dermatology residents.

Open-Ended Feedback—Voting group members were able to provide open-ended feedback for each of the sets of topics after the survey, which the steering committee utilized to modify the topics as needed for the final voting round. For example, “structural racism/discrimination” was originally mentioned as a topic, but several participants suggested including specific types of racism; therefore, the wording was changed to “racism: types, definitions” to encompass broader definitions and types of racism.

Survey Results—Two genres of topics were surveyed in each voting round: clinical and nonclinical. Participants voted on a total of 61 topics, with 23 ultimately selected in the final list of consensus curricular topics. Of those, 9 were clinical and 14 nonclinical. All topics deemed necessary for inclusion in residency curricula are presented in eTables 1 and 2.

During the first round of voting, the e-Delphi panel reached a consensus to include the following 17 topics as essential to dermatology residency training (along with the percentage of voters who classified them as probably essential or definitely essential): how to mitigate bias in clinical and workplace settings (100% [40/40]); social determinants of health-related disparities in dermatology (100% [40/40]); hairstyling practices across different hair textures (100% [40/40]); definitions and examples of microaggressions (97.50% [39/40]); definition, background, and types of bias (97.50% [39/40]); manifestations of bias in the clinical setting (97.44% [38/39]); racial and ethnic disparities in dermatology (97.44% [38/39]); keloids (97.37% [37/38]); differences in dermoscopic presentations in skin of color (97.30% [36/37]); skin cancer in patients with skin of color (97.30% [36/37]); disparities due to bias (95.00% [38/40]); how to apply cultural humility and safety to patients of different cultural backgrounds (94.87% [37/40]); best practices in providing care to patients with limited English proficiency (94.87% [37/40]); hair loss in patients with textured hair (94.74% [36/38]); pseudofolliculitis barbae and acne keloidalis nuchae (94.60% [35/37]); disparities regarding people experiencing homelessness (92.31% [36/39]); and definitions and types of racism and other forms of discrimination (92.31% [36/39]). eTable 1 provides a list of suggested resources to incorporate these topics into the educational components of residency curricula. The resources provided were not part of the voting process, and they were not considered in the consensus analysis; they are included here as suggested educational catalysts.

During the second round of voting, 25 topics were evaluated. Of those, the following 6 topics were proposed to be included as essential in residency training: differences in prevalence and presentation of common inflammatory disorders (100% [29/29]); manifestations of bias in the learning environment (96.55%); antiracist action and how to decrease the effects of structural racism in clinical and educational settings (96.55% [28/29]); diversity of images in dermatology education (96.55% [28/29]); pigmentary disorders and their psychological effects (96.55% [28/29]); and LGBTQ (lesbian, gay, bisexual, transgender, and queer) dermatologic health care (96.55% [28/29]). eTable 2 includes these topics as well as suggested resources to help incorporate them into training.

Comment

This study utilized a modified e-Delphi technique to identify relevant clinical and nonclinical DEI topics that should be incorporated into dermatology residency curricula. The panel members reached a consensus for 9 clinical DEI-related topics. The respondents agreed that the topics related to skin and hair conditions in patients with skin of color as well as textured hair were crucial to residency education. Skin cancer, hair loss, pseudofolliculitis barbae, acne keloidalis nuchae, keloids, pigmentary disorders, and their varying presentations in patients with skin of color were among the recommended topics. The panel also recommended educating residents on the variable visual presentations of inflammatory conditions in skin of color. Addressing the needs of diverse patients—for example, those belonging to the LGBTQ community—also was deemed important for inclusion.

The remaining 14 chosen topics were nonclinical items addressing concepts such as bias and health care disparities as well as cultural humility and safety.⁹ Cultural humility and safety focus on developing cultural awareness by creating a safe setting for patients rather than encouraging power relationships between them and their physicians. Various topics related to racism also were recommended to be included in residency curricula, including education on implementation of antiracist action in the workplace.

Many of the nonclinical topics are intertwined; for instance, learning about health care disparities in patients with limited English proficiency allows for improved best practices in delivering care to patients from this population. The first step in overcoming bias and subsequent disparities is acknowledging how the perpetuation of bias leads to disparities after being taught tools to recognize it.

Our group’s guidance on DEI topics should help dermatology residency program leaders as they design and refine program curricula. There are multiple avenues for incorporating education on these topics, including lectures, interactive workshops, role-playing sessions, book or journal clubs, and discussion circles. Many of these topics/programs may already be included in programs’ didactic curricula, which would minimize the burden of finding space to educate on these topics. Institutional cultural change is key to ensuring truly diverse, equitable, and inclusive workplaces. Educating tomorrow’s dermatologists on these topics is a first step toward achieving that cultural change.

Limitations—A limitation of this e-Delphi survey is that only a selection of experts in this field was included. Additionally, we were concerned that the Likert scale format and the bar we set for inclusion and exclusion may have failed to adequately capture participants’ nuanced opinions. As such, participants were able to provide open-ended feedback, and suggestions for alternate wording or other changes were considered by the steering committee. Finally, inclusion recommendations identified in this survey were developed specifically for US dermatology residents.

Conclusion

In this e-Delphi consensus assessment of DEI-related topics, we recommend the inclusion of 23 topics into dermatology residency program curricula to improve medical training and the patient-physician relationship as well as to create better health outcomes. We also provide specific sample resource recommendations in eTables 1 and 2 to facilitate inclusion of these topics into residency curricula across the country.

Diversity, equity, and inclusion (DEI) programs seek to improve dermatologic education and clinical care for an increasingly diverse patient population as well as to recruit and sustain a physician workforce that reflects the diversity of the patients they serve.^1,2 In dermatology, only 4.2% and 3.0% of practicing dermatologists self-identify as being of Hispanic and African American ethnicity, respectively, compared with 18.5% and 13.4% of the general population, respectively.³ Creating an educational system that works to meet the goals of DEI is essential to improve health outcomes and address disparities. The lack of robust DEI-related curricula during residency training may limit the ability of practicing dermatologists to provide comprehensive and culturally sensitive care. It has been shown that racial concordance between patients and physicians has a positive impact on patient satisfaction by fostering a trusting patient-physician relationship.⁴

It is the responsibility of all dermatologists to create an environment where patients from any background can feel comfortable, which can be cultivated by establishing patient-centered communication and cultural humility.⁵ These skills can be strengthened via the implementation of DEI-related curricula during residency training. Augmenting exposure of these topics during training can optimize the delivery of dermatologic care by providing residents with the tools and confidence needed to care for patients of culturally diverse backgrounds. Enhancing DEI education is crucial to not only improve the recognition and treatment of dermatologic conditions in all skin and hair types but also to minimize misconceptions, stigma, health disparities, and discrimination faced by historically marginalized communities. Creating a culture of inclusion is of paramount importance to build successful relationships with patients and colleagues of culturally diverse backgrounds.⁶

There are multiple efforts underway to increase DEI education across the field of dermatology, including the development of DEI task forces in professional organizations and societies that serve to expand DEI-related research, mentorship, and education. The American Academy of Dermatology has been leading efforts to create a curriculum focused on skin of color, particularly addressing inadequate educational training on how dermatologic conditions manifest in this population.⁷ The Skin of Color Society has similar efforts underway and is developing a speakers bureau to give leading experts a platform to lecture dermatology trainees as well as patient and community audiences on various topics in skin of color.⁸ These are just 2 of many professional dermatology organizations that are advocating for expanded education on DEI; however, consistently integrating DEI-related topics into dermatology residency training curricula remains a gap in pedagogy. To identify the DEI-related topics of greatest relevance to the dermatology resident curricula, we implemented a modified electronic Delphi (e-Delphi) consensus process to provide standardized recommendations.

Methods

A 2-round modified e-Delphi method was utilized (Figure). An initial list of potential curricular topics was formulated by an expert panel consisting of 5 dermatologists from the Association of Professors of Dermatology DEI subcommittee and the American Academy of Dermatology Diversity Task Force (A.M.A., S.B., R.V., S.D.W., J.I.S.). Initial topics were selected via several meetings among the panel members to discuss existing DEI concerns and issues that were deemed relevant due to education gaps in residency training. The list of topics was further expanded with recommendations obtained via an email sent to dermatology program directors on the Association of Professors of Dermatology listserve, which solicited voluntary participation of academic dermatologists, including program directors and dermatology residents.

There were 2 voting rounds, with each round consisting of questions scored on a Likert scale ranging from 1 to 5 (1=not essential, 2=probably not essential, 3=neutral, 4=probably essential, 5=definitely essential). The inclusion criteria to classify a topic as necessary for integration into the dermatology residency curriculum included 95% (18/19) or more of respondents rating the topic as probably essential or definitely essential; if more than 90% (17/19) of respondents rated the topic as probably essential or definitely essential and less than 10% (2/19) rated it as not essential or probably not essential, the topic was still included as part of the suggested curriculum. Topics that received ratings of probably essential or definitely essential by less than 80% (15/19) of respondents were removed from consideration. The topics that did not meet inclusion or exclusion criteria during the first round of voting were refined by the e-Delphi steering committee (V.S.E-C. and F-A.R.) based on open-ended feedback from the voting group provided at the end of the survey and subsequently passed to the second round of voting.

Results

Participants—A total of 19 respondents participated in both voting rounds, the majority (80% [15/19]) of whom were program directors or dermatologists affiliated with academia or development of DEI education; the remaining 20% [4/19]) were dermatology residents.

Open-Ended Feedback—Voting group members were able to provide open-ended feedback for each of the sets of topics after the survey, which the steering committee utilized to modify the topics as needed for the final voting round. For example, “structural racism/discrimination” was originally mentioned as a topic, but several participants suggested including specific types of racism; therefore, the wording was changed to “racism: types, definitions” to encompass broader definitions and types of racism.

Survey Results—Two genres of topics were surveyed in each voting round: clinical and nonclinical. Participants voted on a total of 61 topics, with 23 ultimately selected in the final list of consensus curricular topics. Of those, 9 were clinical and 14 nonclinical. All topics deemed necessary for inclusion in residency curricula are presented in eTables 1 and 2.

During the first round of voting, the e-Delphi panel reached a consensus to include the following 17 topics as essential to dermatology residency training (along with the percentage of voters who classified them as probably essential or definitely essential): how to mitigate bias in clinical and workplace settings (100% [40/40]); social determinants of health-related disparities in dermatology (100% [40/40]); hairstyling practices across different hair textures (100% [40/40]); definitions and examples of microaggressions (97.50% [39/40]); definition, background, and types of bias (97.50% [39/40]); manifestations of bias in the clinical setting (97.44% [38/39]); racial and ethnic disparities in dermatology (97.44% [38/39]); keloids (97.37% [37/38]); differences in dermoscopic presentations in skin of color (97.30% [36/37]); skin cancer in patients with skin of color (97.30% [36/37]); disparities due to bias (95.00% [38/40]); how to apply cultural humility and safety to patients of different cultural backgrounds (94.87% [37/40]); best practices in providing care to patients with limited English proficiency (94.87% [37/40]); hair loss in patients with textured hair (94.74% [36/38]); pseudofolliculitis barbae and acne keloidalis nuchae (94.60% [35/37]); disparities regarding people experiencing homelessness (92.31% [36/39]); and definitions and types of racism and other forms of discrimination (92.31% [36/39]). eTable 1 provides a list of suggested resources to incorporate these topics into the educational components of residency curricula. The resources provided were not part of the voting process, and they were not considered in the consensus analysis; they are included here as suggested educational catalysts.

During the second round of voting, 25 topics were evaluated. Of those, the following 6 topics were proposed to be included as essential in residency training: differences in prevalence and presentation of common inflammatory disorders (100% [29/29]); manifestations of bias in the learning environment (96.55%); antiracist action and how to decrease the effects of structural racism in clinical and educational settings (96.55% [28/29]); diversity of images in dermatology education (96.55% [28/29]); pigmentary disorders and their psychological effects (96.55% [28/29]); and LGBTQ (lesbian, gay, bisexual, transgender, and queer) dermatologic health care (96.55% [28/29]). eTable 2 includes these topics as well as suggested resources to help incorporate them into training.

Comment

This study utilized a modified e-Delphi technique to identify relevant clinical and nonclinical DEI topics that should be incorporated into dermatology residency curricula. The panel members reached a consensus for 9 clinical DEI-related topics. The respondents agreed that the topics related to skin and hair conditions in patients with skin of color as well as textured hair were crucial to residency education. Skin cancer, hair loss, pseudofolliculitis barbae, acne keloidalis nuchae, keloids, pigmentary disorders, and their varying presentations in patients with skin of color were among the recommended topics. The panel also recommended educating residents on the variable visual presentations of inflammatory conditions in skin of color. Addressing the needs of diverse patients—for example, those belonging to the LGBTQ community—also was deemed important for inclusion.

The remaining 14 chosen topics were nonclinical items addressing concepts such as bias and health care disparities as well as cultural humility and safety.⁹ Cultural humility and safety focus on developing cultural awareness by creating a safe setting for patients rather than encouraging power relationships between them and their physicians. Various topics related to racism also were recommended to be included in residency curricula, including education on implementation of antiracist action in the workplace.

Many of the nonclinical topics are intertwined; for instance, learning about health care disparities in patients with limited English proficiency allows for improved best practices in delivering care to patients from this population. The first step in overcoming bias and subsequent disparities is acknowledging how the perpetuation of bias leads to disparities after being taught tools to recognize it.

Our group’s guidance on DEI topics should help dermatology residency program leaders as they design and refine program curricula. There are multiple avenues for incorporating education on these topics, including lectures, interactive workshops, role-playing sessions, book or journal clubs, and discussion circles. Many of these topics/programs may already be included in programs’ didactic curricula, which would minimize the burden of finding space to educate on these topics. Institutional cultural change is key to ensuring truly diverse, equitable, and inclusive workplaces. Educating tomorrow’s dermatologists on these topics is a first step toward achieving that cultural change.

Limitations—A limitation of this e-Delphi survey is that only a selection of experts in this field was included. Additionally, we were concerned that the Likert scale format and the bar we set for inclusion and exclusion may have failed to adequately capture participants’ nuanced opinions. As such, participants were able to provide open-ended feedback, and suggestions for alternate wording or other changes were considered by the steering committee. Finally, inclusion recommendations identified in this survey were developed specifically for US dermatology residents.

Conclusion

In this e-Delphi consensus assessment of DEI-related topics, we recommend the inclusion of 23 topics into dermatology residency program curricula to improve medical training and the patient-physician relationship as well as to create better health outcomes. We also provide specific sample resource recommendations in eTables 1 and 2 to facilitate inclusion of these topics into residency curricula across the country.