Ronda S. Farah, MD

To the Editor:

There is an irrefutable trend toward urban dermatology practice in the United States, leading to growing problems with rural access to care. The provision of rural clinical experiences and telehealth in dermatology residency training might increase the likelihood of trainees establishing a rural practice.

In 2017, the American Academy of Dermatology released an updated statement supporting direct patient access to board-certified dermatologists in an effort to reduce morbidity and mortality associated with skin disease.¹ Twenty percent of the US population lives in a rural and medically underserved location, yet these areas remain largely underserved, in part because of an irrefutable trend toward urban dermatology practice.^2-4 Successful approaches to improving rural access to dermatology care are poorly defined in the literature.

Several variables have been shown to influence a young physician’s decision to establish a clinical practice in geographically isolated areas, including rural upbringing, longitudinal rural clinical experiences during medical training, and family influences.⁵ Location of residency training is an additional variable that impacts practice location, though migration following dermatology residency is a complex phenomenon. However, training location does not guarantee retention of dermatology graduates in any particular geographic area.⁶ Practice incentives and stipends might encourage rural dermatology practice, yet these programs are underfunded. Last, telemedicine in dermatology (including teledermatology and teledermoscopy), though not always an ideal substitute for a live visit, can improve access to care in geographically isolated or underserved areas in general.^7-9

Focused recruitment of medical students interested in rural dermatology practice to accredited dermatology residency programs aligned with this goal represents another approach to improve geographic diversity in the field of dermatology. Online access to this information would be useful for both applicants and their mentors.

We assessed viewable online curricula related to rural dermatology and telemedicine experiences at all Accreditation Council for Graduate Medical Education (ACGME)–accredited residency programs. Telemedicine experiences at Veterans Health Administration (VHA) health systems also were assessed.

Methods

This study was exempt from review by the institutional review board at the University of Minnesota (Minneapolis, Minnesota)(IRB #STUDY00004915) because no human subjects were involved. Online curricula of all ACGME-accredited dermatology residency programs in the United States and Puerto Rico were reviewed from November to December 2018. The following information was recorded: specialized “rural-track” training; optional elective time in rural settings; teledermatology training; and teledermoscopy training.

Additionally, population density at each program’s primary location was determined using US Census Bureau data and with consideration to communities contained within particular Metropolitan Statistical Areas (MSAs)(eTable). Data were obtained from the VHA system to assess teledermatology services at VHA locations affiliated with residency programs.

Results

Of 154 dermatology residency programs identified in the United States and Puerto Rico, 142 were accredited at the time of data collection. Fifteen (10%) were based in communities of 50,000 individuals or fewer that were not near a large metropolitan area. One program (<1%) offered a specific rural track. Fifty-six programs (39%) cited optional rotations or clinical electives, or both, that could be utilized for a rural experience. Eighteen (12%) offered teledermatology experiences and 1 (<1%) offered teledermoscopy during training. Fifty-three programs (37%) offered a rotation at a VHA hospital that had an active teledermatology service.

Comment

Program websites are a free and easily accessible means of acquiring relevant information. The paucity of readily available data on rural dermatology and teledermatology opportunities is unfortunate and a detriment to dermatology residency applicants interested in rural practice, which may result in a missed opportunity to foster a true passion for rural medicine. A brief comment on a website can be impactful, leading to a postgraduate year 4 dermatology elective rotation at a prospective fellowship training site or a rural dermatology experience.

The paucity of dermatologists working directly in rural areas has led to development of teledermatology initiatives to reach deeply into underserved regions. One of the largest providers of teledermatology is the VHA, which standardized its teledermatology efforts in 2012 and provides remarkable educational opportunities for dermatology residents. However, many residency program and VHA websites provide no information about the participation of dermatology residents in the provision of teledermatology services.

A limitation of this study is that it is based on online published curricula. Dermatology residency programs with excellent rural curricula that are not published online might exist.

Residency program directors with an interest in geographic diversity are encouraged to provide rural and teledermatology opportunities and to update these offerings on their websites, which is a simple modifiable strategy that can impact the rural dermatology care gap by recruiting students interested in filling this role. These efforts should be studied to determine whether this strategy impacts resident selection as well as whether focused rural and telemedicine exposure during training increases the likelihood of establishing a rural dermatology practice in the future.

To the Editor:

There is an irrefutable trend toward urban dermatology practice in the United States, leading to growing problems with rural access to care. The provision of rural clinical experiences and telehealth in dermatology residency training might increase the likelihood of trainees establishing a rural practice.

In 2017, the American Academy of Dermatology released an updated statement supporting direct patient access to board-certified dermatologists in an effort to reduce morbidity and mortality associated with skin disease.¹ Twenty percent of the US population lives in a rural and medically underserved location, yet these areas remain largely underserved, in part because of an irrefutable trend toward urban dermatology practice.^2-4 Successful approaches to improving rural access to dermatology care are poorly defined in the literature.

Several variables have been shown to influence a young physician’s decision to establish a clinical practice in geographically isolated areas, including rural upbringing, longitudinal rural clinical experiences during medical training, and family influences.⁵ Location of residency training is an additional variable that impacts practice location, though migration following dermatology residency is a complex phenomenon. However, training location does not guarantee retention of dermatology graduates in any particular geographic area.⁶ Practice incentives and stipends might encourage rural dermatology practice, yet these programs are underfunded. Last, telemedicine in dermatology (including teledermatology and teledermoscopy), though not always an ideal substitute for a live visit, can improve access to care in geographically isolated or underserved areas in general.^7-9

Focused recruitment of medical students interested in rural dermatology practice to accredited dermatology residency programs aligned with this goal represents another approach to improve geographic diversity in the field of dermatology. Online access to this information would be useful for both applicants and their mentors.

We assessed viewable online curricula related to rural dermatology and telemedicine experiences at all Accreditation Council for Graduate Medical Education (ACGME)–accredited residency programs. Telemedicine experiences at Veterans Health Administration (VHA) health systems also were assessed.

Methods

This study was exempt from review by the institutional review board at the University of Minnesota (Minneapolis, Minnesota)(IRB #STUDY00004915) because no human subjects were involved. Online curricula of all ACGME-accredited dermatology residency programs in the United States and Puerto Rico were reviewed from November to December 2018. The following information was recorded: specialized “rural-track” training; optional elective time in rural settings; teledermatology training; and teledermoscopy training.

Additionally, population density at each program’s primary location was determined using US Census Bureau data and with consideration to communities contained within particular Metropolitan Statistical Areas (MSAs)(eTable). Data were obtained from the VHA system to assess teledermatology services at VHA locations affiliated with residency programs.

Results

Of 154 dermatology residency programs identified in the United States and Puerto Rico, 142 were accredited at the time of data collection. Fifteen (10%) were based in communities of 50,000 individuals or fewer that were not near a large metropolitan area. One program (<1%) offered a specific rural track. Fifty-six programs (39%) cited optional rotations or clinical electives, or both, that could be utilized for a rural experience. Eighteen (12%) offered teledermatology experiences and 1 (<1%) offered teledermoscopy during training. Fifty-three programs (37%) offered a rotation at a VHA hospital that had an active teledermatology service.

Comment

Program websites are a free and easily accessible means of acquiring relevant information. The paucity of readily available data on rural dermatology and teledermatology opportunities is unfortunate and a detriment to dermatology residency applicants interested in rural practice, which may result in a missed opportunity to foster a true passion for rural medicine. A brief comment on a website can be impactful, leading to a postgraduate year 4 dermatology elective rotation at a prospective fellowship training site or a rural dermatology experience.

The paucity of dermatologists working directly in rural areas has led to development of teledermatology initiatives to reach deeply into underserved regions. One of the largest providers of teledermatology is the VHA, which standardized its teledermatology efforts in 2012 and provides remarkable educational opportunities for dermatology residents. However, many residency program and VHA websites provide no information about the participation of dermatology residents in the provision of teledermatology services.

A limitation of this study is that it is based on online published curricula. Dermatology residency programs with excellent rural curricula that are not published online might exist.

Residency program directors with an interest in geographic diversity are encouraged to provide rural and teledermatology opportunities and to update these offerings on their websites, which is a simple modifiable strategy that can impact the rural dermatology care gap by recruiting students interested in filling this role. These efforts should be studied to determine whether this strategy impacts resident selection as well as whether focused rural and telemedicine exposure during training increases the likelihood of establishing a rural dermatology practice in the future.

To the Editor:

There is an irrefutable trend toward urban dermatology practice in the United States, leading to growing problems with rural access to care. The provision of rural clinical experiences and telehealth in dermatology residency training might increase the likelihood of trainees establishing a rural practice.

In 2017, the American Academy of Dermatology released an updated statement supporting direct patient access to board-certified dermatologists in an effort to reduce morbidity and mortality associated with skin disease.¹ Twenty percent of the US population lives in a rural and medically underserved location, yet these areas remain largely underserved, in part because of an irrefutable trend toward urban dermatology practice.^2-4 Successful approaches to improving rural access to dermatology care are poorly defined in the literature.

Several variables have been shown to influence a young physician’s decision to establish a clinical practice in geographically isolated areas, including rural upbringing, longitudinal rural clinical experiences during medical training, and family influences.⁵ Location of residency training is an additional variable that impacts practice location, though migration following dermatology residency is a complex phenomenon. However, training location does not guarantee retention of dermatology graduates in any particular geographic area.⁶ Practice incentives and stipends might encourage rural dermatology practice, yet these programs are underfunded. Last, telemedicine in dermatology (including teledermatology and teledermoscopy), though not always an ideal substitute for a live visit, can improve access to care in geographically isolated or underserved areas in general.^7-9

Focused recruitment of medical students interested in rural dermatology practice to accredited dermatology residency programs aligned with this goal represents another approach to improve geographic diversity in the field of dermatology. Online access to this information would be useful for both applicants and their mentors.

We assessed viewable online curricula related to rural dermatology and telemedicine experiences at all Accreditation Council for Graduate Medical Education (ACGME)–accredited residency programs. Telemedicine experiences at Veterans Health Administration (VHA) health systems also were assessed.

Methods

This study was exempt from review by the institutional review board at the University of Minnesota (Minneapolis, Minnesota)(IRB #STUDY00004915) because no human subjects were involved. Online curricula of all ACGME-accredited dermatology residency programs in the United States and Puerto Rico were reviewed from November to December 2018. The following information was recorded: specialized “rural-track” training; optional elective time in rural settings; teledermatology training; and teledermoscopy training.

Additionally, population density at each program’s primary location was determined using US Census Bureau data and with consideration to communities contained within particular Metropolitan Statistical Areas (MSAs)(eTable). Data were obtained from the VHA system to assess teledermatology services at VHA locations affiliated with residency programs.

Results

Of 154 dermatology residency programs identified in the United States and Puerto Rico, 142 were accredited at the time of data collection. Fifteen (10%) were based in communities of 50,000 individuals or fewer that were not near a large metropolitan area. One program (<1%) offered a specific rural track. Fifty-six programs (39%) cited optional rotations or clinical electives, or both, that could be utilized for a rural experience. Eighteen (12%) offered teledermatology experiences and 1 (<1%) offered teledermoscopy during training. Fifty-three programs (37%) offered a rotation at a VHA hospital that had an active teledermatology service.

Comment

Program websites are a free and easily accessible means of acquiring relevant information. The paucity of readily available data on rural dermatology and teledermatology opportunities is unfortunate and a detriment to dermatology residency applicants interested in rural practice, which may result in a missed opportunity to foster a true passion for rural medicine. A brief comment on a website can be impactful, leading to a postgraduate year 4 dermatology elective rotation at a prospective fellowship training site or a rural dermatology experience.

The paucity of dermatologists working directly in rural areas has led to development of teledermatology initiatives to reach deeply into underserved regions. One of the largest providers of teledermatology is the VHA, which standardized its teledermatology efforts in 2012 and provides remarkable educational opportunities for dermatology residents. However, many residency program and VHA websites provide no information about the participation of dermatology residents in the provision of teledermatology services.

A limitation of this study is that it is based on online published curricula. Dermatology residency programs with excellent rural curricula that are not published online might exist.

Residency program directors with an interest in geographic diversity are encouraged to provide rural and teledermatology opportunities and to update these offerings on their websites, which is a simple modifiable strategy that can impact the rural dermatology care gap by recruiting students interested in filling this role. These efforts should be studied to determine whether this strategy impacts resident selection as well as whether focused rural and telemedicine exposure during training increases the likelihood of establishing a rural dermatology practice in the future.

The Diagnosis: Primary Cutaneous Follicle Center Lymphoma

Immunohistochemistry revealed a nodular infiltrate consisting of small to large atypical lymphocytes forming an irregular germinal center with notably thinned mantle zones and lack of polarization (Figure, A). Atypical cells stained positively with Bcl-6, and CD20 was diffusely positive (Figure, B-D). Bcl-2 and CD3 colocalized to the reactive T-cell infiltrate, and CD10 was largely negative. Further workup with bone marrow biopsy and full-body positron emission tomography-computed tomography was unremarkable. Given these findings, a diagnosis of primary cutaneous follicle center lymphoma (FCL) was made. At 1 month following radiation therapy, complete clinical clearance of the lymphoma was achieved.

Follicle center lymphoma, also known as cutaneous follicular lymphoma, is the most common subtype of primary cutaneous B-cell lymphomas, representing approximately 57% of cases.¹ Follicle center lymphoma typically affects older, non-Hispanic white adults with a median age of onset of 60 years. It has a predilection for the head, neck, and trunk.² Lesions present as solitary erythematous to violaceous papules, plaques, or nodules, but they can more rarely be multifocal.³ Clinical diagnosis of FCL can be difficult, with papular lesions resembling acne, rosacea, folliculitis, or arthropod assault.^4,5 As such, diagnosis of FCL typically relies on histopathologic analysis.

Histologically, FCL can present in several different patterns including follicular, nodular, diffuse, or a pleomorphic mix of these.^2,6 The cells are comprised of germinal center B cells, staining positively for Bcl-6, CD20, and CD79a.⁷ Tumor cells do not exhibit the t(14;18) translocation seen in nodal follicular lymphomas.^2,8 Unlike marginal zone lymphoma, FCL stains negatively for Bcl-2 and multiple myeloma 1/interferon regulatory factor 4 (MUM1/IRF-4).^2,9 Forkhead box P1 (FOXP1) also is usually negative, but its presence can indicate a poorer prognosis.² It is important to distinguish primary cutaneous B-cell lymphomas from systemic B-cell lymphoma with secondary cutaneous involvement, as they have a different clinical prognosis and management course. Further workup includes bone marrow biopsy, serum analysis for clonal involvement, and positron emission tomography-computed tomography imaging. Follicle center lymphoma generally has an indolent disease course with a favorable 5-year survival rate of approximately 95%.^6,8

Untreated lesions may enlarge slowly or even spontaneously involute.¹⁰ The histologic growth pattern and number of lesions do not affect prognosis, but presence on the legs has a 5-year survival rate of 41%.² Extracutaneous dissemination can occur in 5% to 10% of cases.² Given the slow progression of FCL, conservative management with observation is an option. However, curative treatment can be reasonably attempted for solitary lesions by excision or radiation. Treatment of FCL often can be complicated by its predilection for the head and neck. Other treatment modalities include topical steroids, imiquimod, nitrogen mustard, and bexarotene.¹⁰ More generalized involvement may require systemic therapy with rituximab or chemotherapy. Recurrence after therapy is common, reported in 46.5% of patients, but does not affect prognosis.²

The Diagnosis: Primary Cutaneous Follicle Center Lymphoma

Immunohistochemistry revealed a nodular infiltrate consisting of small to large atypical lymphocytes forming an irregular germinal center with notably thinned mantle zones and lack of polarization (Figure, A). Atypical cells stained positively with Bcl-6, and CD20 was diffusely positive (Figure, B-D). Bcl-2 and CD3 colocalized to the reactive T-cell infiltrate, and CD10 was largely negative. Further workup with bone marrow biopsy and full-body positron emission tomography-computed tomography was unremarkable. Given these findings, a diagnosis of primary cutaneous follicle center lymphoma (FCL) was made. At 1 month following radiation therapy, complete clinical clearance of the lymphoma was achieved.

Follicle center lymphoma, also known as cutaneous follicular lymphoma, is the most common subtype of primary cutaneous B-cell lymphomas, representing approximately 57% of cases.¹ Follicle center lymphoma typically affects older, non-Hispanic white adults with a median age of onset of 60 years. It has a predilection for the head, neck, and trunk.² Lesions present as solitary erythematous to violaceous papules, plaques, or nodules, but they can more rarely be multifocal.³ Clinical diagnosis of FCL can be difficult, with papular lesions resembling acne, rosacea, folliculitis, or arthropod assault.^4,5 As such, diagnosis of FCL typically relies on histopathologic analysis.

Histologically, FCL can present in several different patterns including follicular, nodular, diffuse, or a pleomorphic mix of these.^2,6 The cells are comprised of germinal center B cells, staining positively for Bcl-6, CD20, and CD79a.⁷ Tumor cells do not exhibit the t(14;18) translocation seen in nodal follicular lymphomas.^2,8 Unlike marginal zone lymphoma, FCL stains negatively for Bcl-2 and multiple myeloma 1/interferon regulatory factor 4 (MUM1/IRF-4).^2,9 Forkhead box P1 (FOXP1) also is usually negative, but its presence can indicate a poorer prognosis.² It is important to distinguish primary cutaneous B-cell lymphomas from systemic B-cell lymphoma with secondary cutaneous involvement, as they have a different clinical prognosis and management course. Further workup includes bone marrow biopsy, serum analysis for clonal involvement, and positron emission tomography-computed tomography imaging. Follicle center lymphoma generally has an indolent disease course with a favorable 5-year survival rate of approximately 95%.^6,8

Untreated lesions may enlarge slowly or even spontaneously involute.¹⁰ The histologic growth pattern and number of lesions do not affect prognosis, but presence on the legs has a 5-year survival rate of 41%.² Extracutaneous dissemination can occur in 5% to 10% of cases.² Given the slow progression of FCL, conservative management with observation is an option. However, curative treatment can be reasonably attempted for solitary lesions by excision or radiation. Treatment of FCL often can be complicated by its predilection for the head and neck. Other treatment modalities include topical steroids, imiquimod, nitrogen mustard, and bexarotene.¹⁰ More generalized involvement may require systemic therapy with rituximab or chemotherapy. Recurrence after therapy is common, reported in 46.5% of patients, but does not affect prognosis.²

The Diagnosis: Primary Cutaneous Follicle Center Lymphoma

Immunohistochemistry revealed a nodular infiltrate consisting of small to large atypical lymphocytes forming an irregular germinal center with notably thinned mantle zones and lack of polarization (Figure, A). Atypical cells stained positively with Bcl-6, and CD20 was diffusely positive (Figure, B-D). Bcl-2 and CD3 colocalized to the reactive T-cell infiltrate, and CD10 was largely negative. Further workup with bone marrow biopsy and full-body positron emission tomography-computed tomography was unremarkable. Given these findings, a diagnosis of primary cutaneous follicle center lymphoma (FCL) was made. At 1 month following radiation therapy, complete clinical clearance of the lymphoma was achieved.

Follicle center lymphoma, also known as cutaneous follicular lymphoma, is the most common subtype of primary cutaneous B-cell lymphomas, representing approximately 57% of cases.¹ Follicle center lymphoma typically affects older, non-Hispanic white adults with a median age of onset of 60 years. It has a predilection for the head, neck, and trunk.² Lesions present as solitary erythematous to violaceous papules, plaques, or nodules, but they can more rarely be multifocal.³ Clinical diagnosis of FCL can be difficult, with papular lesions resembling acne, rosacea, folliculitis, or arthropod assault.^4,5 As such, diagnosis of FCL typically relies on histopathologic analysis.

Histologically, FCL can present in several different patterns including follicular, nodular, diffuse, or a pleomorphic mix of these.^2,6 The cells are comprised of germinal center B cells, staining positively for Bcl-6, CD20, and CD79a.⁷ Tumor cells do not exhibit the t(14;18) translocation seen in nodal follicular lymphomas.^2,8 Unlike marginal zone lymphoma, FCL stains negatively for Bcl-2 and multiple myeloma 1/interferon regulatory factor 4 (MUM1/IRF-4).^2,9 Forkhead box P1 (FOXP1) also is usually negative, but its presence can indicate a poorer prognosis.² It is important to distinguish primary cutaneous B-cell lymphomas from systemic B-cell lymphoma with secondary cutaneous involvement, as they have a different clinical prognosis and management course. Further workup includes bone marrow biopsy, serum analysis for clonal involvement, and positron emission tomography-computed tomography imaging. Follicle center lymphoma generally has an indolent disease course with a favorable 5-year survival rate of approximately 95%.^6,8

Untreated lesions may enlarge slowly or even spontaneously involute.¹⁰ The histologic growth pattern and number of lesions do not affect prognosis, but presence on the legs has a 5-year survival rate of 41%.² Extracutaneous dissemination can occur in 5% to 10% of cases.² Given the slow progression of FCL, conservative management with observation is an option. However, curative treatment can be reasonably attempted for solitary lesions by excision or radiation. Treatment of FCL often can be complicated by its predilection for the head and neck. Other treatment modalities include topical steroids, imiquimod, nitrogen mustard, and bexarotene.¹⁰ More generalized involvement may require systemic therapy with rituximab or chemotherapy. Recurrence after therapy is common, reported in 46.5% of patients, but does not affect prognosis.²

To the Editor:

Hereditary hypotrichosis simplex (HHS)(Online Mendelian Inheritance in Man [OMIM] 146520) is a rare form of hypotrichosis that typically presents in school-aged children as worsening hair loss localized to the scalp.¹ Most patients are unaffected at birth and otherwise healthy without abnormalities of the nails, teeth, or perspiration. Examination of the scalp reveals normal follicular ostia and absence of scale and erythema; however, decreased follicular density may be noted.¹ The histopathologic findings of HHS reveal velluslike hair follicles without associated fibrosis or inflammation.² Examination of hair follicles with light microscopy is unremarkable.^3,4 Historically, this condition has been largely regarded as autosomal dominant, with variable severity also described within families. Herein, we report a case of this rare disease in a child, with 2 family members displaying a less severe phenotype.

A 7-year-old girl presented with gradual thinning of the scalp hair of 3 to 4 years’ duration. Her mother reported the patient had normal hair density at birth. Over the next several years, she was noted to have an inability to grow lengthy hair. At approximately 3 years of age, thinning of scalp hair was identified. There was no prior history of increased shedding, hypohidrosis, or tooth or nail abnormalities. Family history revealed fine hair in her older sister and fine thin hair at the frontal scalp in her mother. Her mother reported similar inability to grow lengthy hair. Physical examination of the patient demonstrated short blonde hair with diffuse thinning of the crown (Figure 1). The longest hair was approximately 10 cm in length. Follicular ostia were without erythema or scale but notably fewer in number on the crown. Eyebrows, eyelashes, teeth, and fingernails were without abnormalities. A hair pull test was negative and hair mount revealed normal bulb and shaft. Microscopy of hair shafts under polarized light was unremarkable.

Two punch biopsies were obtained and submitted for vertical and horizontal sectioning. Sections demonstrated an intact epidermis, decreased follicle number, and small follicles with hypoplastic velluslike appearance (Figure 2). Fibrosis and inflammation were not seen; there was no increase in catagen or telogen hairs. Clinical and histopathological findings were consistent with HHS.

Hereditary hypotrichosis localized to the scalp was first described by Toribio and Quinones⁵ in 1974 in a large Spanish family presenting with normal scalp hair at birth followed by gradual diffuse hair loss. Hair loss that usually began in school-aged children with subsequent few fine hairs remaining on the scalp by the third decade of life was identified in these individuals.Eyelashes, eyebrows, pubic, axillary, and other truncal hairs were normal.⁵ Several similar cases of HHS localized to the scalp have since been reported.^2,6 Hereditary hypotrichosis simplex is inherited in an autosomal-dominant fashion, with the exception of 1 reported sporadic case.³

Research on HHS has primarily focused on genetic analyses of several affected families. Betz et al⁷ mapped the gene for HHS to band 6p21.3 in 2 families of Danish origin and in the Spanish family initially described by Toribio and Quinones.⁵ Three years later, a nonsense mutation in the CDSN gene encoding corneodesmosin was described.⁸ Despite these genetic advances, the pathogenesis of HHS and the role that corneodesmosin may play remain unclear.

Generalized forms of hypotrichosis (OMIM #605389) have long been reported and described as loss of scalp hair with involvement of eyebrows, eyelashes, and other body hair.⁹ Genetic studies have allowed for genome-wide linkage analysis, linking 3 families with this more generalized HHS phenotype to chromosome 18; specifically, an Italian family with sparse scalp and body hair but normal eyelashes and eyebrows,⁴ and 2 Pakistani families with thinning scalp hair and sparse truncal hair.¹⁰ A mutation in the APC downregulated 1 gene, APCDD1, also has been identified in these families.¹⁰ These genetic findings indicate that the generalized form of HHS is a distinct syndrome.

The differential diagnosis of HHS includes Marie-Unna hereditary hypotrichosis, loose anagen hair syndrome, trichothiodystrophy, and androgenetic alopecia. Marie-Unna hereditary hypotrichosis usually presents as near-complete absence of scalp hair at birth, development of wiry twisted hair in childhood, and progressive alopecia.³ Loose anagen hair syndrome usually demonstrates a ruffled cuticle on hair pull test and remits in late childhood. Polarization of the hair shaft can identify patients with trichothiodystrophy. Follicular miniaturization may lead one to consider early-onset androgenetic alopecia in some patients.

There is no effective treatment of HHS. Due to potential phenotypic variation, patients should be counseled that they may experience progressive or possible total loss of scalp hair by the third decade of life.^2,3,5 As with other hair loss disorders, wigs or additional over-the-counter cosmetic options may be considered.³ Currently, there are no known patient resources specific for HHS. Therefore, our patient’s family was referred to the National Alopecia Areata Foundation website (https://naaf.org/) for resources on discussing alopecia with school-aged children. The psychological impact of alopecia should not be overlooked and psychiatric referral should be provided, if needed. Examination of family members along with clinical monitoring are recommended. Genetic counseling also may be offered.³

To the Editor:

Hereditary hypotrichosis simplex (HHS)(Online Mendelian Inheritance in Man [OMIM] 146520) is a rare form of hypotrichosis that typically presents in school-aged children as worsening hair loss localized to the scalp.¹ Most patients are unaffected at birth and otherwise healthy without abnormalities of the nails, teeth, or perspiration. Examination of the scalp reveals normal follicular ostia and absence of scale and erythema; however, decreased follicular density may be noted.¹ The histopathologic findings of HHS reveal velluslike hair follicles without associated fibrosis or inflammation.² Examination of hair follicles with light microscopy is unremarkable.^3,4 Historically, this condition has been largely regarded as autosomal dominant, with variable severity also described within families. Herein, we report a case of this rare disease in a child, with 2 family members displaying a less severe phenotype.

A 7-year-old girl presented with gradual thinning of the scalp hair of 3 to 4 years’ duration. Her mother reported the patient had normal hair density at birth. Over the next several years, she was noted to have an inability to grow lengthy hair. At approximately 3 years of age, thinning of scalp hair was identified. There was no prior history of increased shedding, hypohidrosis, or tooth or nail abnormalities. Family history revealed fine hair in her older sister and fine thin hair at the frontal scalp in her mother. Her mother reported similar inability to grow lengthy hair. Physical examination of the patient demonstrated short blonde hair with diffuse thinning of the crown (Figure 1). The longest hair was approximately 10 cm in length. Follicular ostia were without erythema or scale but notably fewer in number on the crown. Eyebrows, eyelashes, teeth, and fingernails were without abnormalities. A hair pull test was negative and hair mount revealed normal bulb and shaft. Microscopy of hair shafts under polarized light was unremarkable.

Two punch biopsies were obtained and submitted for vertical and horizontal sectioning. Sections demonstrated an intact epidermis, decreased follicle number, and small follicles with hypoplastic velluslike appearance (Figure 2). Fibrosis and inflammation were not seen; there was no increase in catagen or telogen hairs. Clinical and histopathological findings were consistent with HHS.

Hereditary hypotrichosis localized to the scalp was first described by Toribio and Quinones⁵ in 1974 in a large Spanish family presenting with normal scalp hair at birth followed by gradual diffuse hair loss. Hair loss that usually began in school-aged children with subsequent few fine hairs remaining on the scalp by the third decade of life was identified in these individuals.Eyelashes, eyebrows, pubic, axillary, and other truncal hairs were normal.⁵ Several similar cases of HHS localized to the scalp have since been reported.^2,6 Hereditary hypotrichosis simplex is inherited in an autosomal-dominant fashion, with the exception of 1 reported sporadic case.³

Research on HHS has primarily focused on genetic analyses of several affected families. Betz et al⁷ mapped the gene for HHS to band 6p21.3 in 2 families of Danish origin and in the Spanish family initially described by Toribio and Quinones.⁵ Three years later, a nonsense mutation in the CDSN gene encoding corneodesmosin was described.⁸ Despite these genetic advances, the pathogenesis of HHS and the role that corneodesmosin may play remain unclear.

Generalized forms of hypotrichosis (OMIM #605389) have long been reported and described as loss of scalp hair with involvement of eyebrows, eyelashes, and other body hair.⁹ Genetic studies have allowed for genome-wide linkage analysis, linking 3 families with this more generalized HHS phenotype to chromosome 18; specifically, an Italian family with sparse scalp and body hair but normal eyelashes and eyebrows,⁴ and 2 Pakistani families with thinning scalp hair and sparse truncal hair.¹⁰ A mutation in the APC downregulated 1 gene, APCDD1, also has been identified in these families.¹⁰ These genetic findings indicate that the generalized form of HHS is a distinct syndrome.

The differential diagnosis of HHS includes Marie-Unna hereditary hypotrichosis, loose anagen hair syndrome, trichothiodystrophy, and androgenetic alopecia. Marie-Unna hereditary hypotrichosis usually presents as near-complete absence of scalp hair at birth, development of wiry twisted hair in childhood, and progressive alopecia.³ Loose anagen hair syndrome usually demonstrates a ruffled cuticle on hair pull test and remits in late childhood. Polarization of the hair shaft can identify patients with trichothiodystrophy. Follicular miniaturization may lead one to consider early-onset androgenetic alopecia in some patients.

There is no effective treatment of HHS. Due to potential phenotypic variation, patients should be counseled that they may experience progressive or possible total loss of scalp hair by the third decade of life.^2,3,5 As with other hair loss disorders, wigs or additional over-the-counter cosmetic options may be considered.³ Currently, there are no known patient resources specific for HHS. Therefore, our patient’s family was referred to the National Alopecia Areata Foundation website (https://naaf.org/) for resources on discussing alopecia with school-aged children. The psychological impact of alopecia should not be overlooked and psychiatric referral should be provided, if needed. Examination of family members along with clinical monitoring are recommended. Genetic counseling also may be offered.³

To the Editor:

Hereditary hypotrichosis simplex (HHS)(Online Mendelian Inheritance in Man [OMIM] 146520) is a rare form of hypotrichosis that typically presents in school-aged children as worsening hair loss localized to the scalp.¹ Most patients are unaffected at birth and otherwise healthy without abnormalities of the nails, teeth, or perspiration. Examination of the scalp reveals normal follicular ostia and absence of scale and erythema; however, decreased follicular density may be noted.¹ The histopathologic findings of HHS reveal velluslike hair follicles without associated fibrosis or inflammation.² Examination of hair follicles with light microscopy is unremarkable.^3,4 Historically, this condition has been largely regarded as autosomal dominant, with variable severity also described within families. Herein, we report a case of this rare disease in a child, with 2 family members displaying a less severe phenotype.

A 7-year-old girl presented with gradual thinning of the scalp hair of 3 to 4 years’ duration. Her mother reported the patient had normal hair density at birth. Over the next several years, she was noted to have an inability to grow lengthy hair. At approximately 3 years of age, thinning of scalp hair was identified. There was no prior history of increased shedding, hypohidrosis, or tooth or nail abnormalities. Family history revealed fine hair in her older sister and fine thin hair at the frontal scalp in her mother. Her mother reported similar inability to grow lengthy hair. Physical examination of the patient demonstrated short blonde hair with diffuse thinning of the crown (Figure 1). The longest hair was approximately 10 cm in length. Follicular ostia were without erythema or scale but notably fewer in number on the crown. Eyebrows, eyelashes, teeth, and fingernails were without abnormalities. A hair pull test was negative and hair mount revealed normal bulb and shaft. Microscopy of hair shafts under polarized light was unremarkable.

Two punch biopsies were obtained and submitted for vertical and horizontal sectioning. Sections demonstrated an intact epidermis, decreased follicle number, and small follicles with hypoplastic velluslike appearance (Figure 2). Fibrosis and inflammation were not seen; there was no increase in catagen or telogen hairs. Clinical and histopathological findings were consistent with HHS.

Hereditary hypotrichosis localized to the scalp was first described by Toribio and Quinones⁵ in 1974 in a large Spanish family presenting with normal scalp hair at birth followed by gradual diffuse hair loss. Hair loss that usually began in school-aged children with subsequent few fine hairs remaining on the scalp by the third decade of life was identified in these individuals.Eyelashes, eyebrows, pubic, axillary, and other truncal hairs were normal.⁵ Several similar cases of HHS localized to the scalp have since been reported.^2,6 Hereditary hypotrichosis simplex is inherited in an autosomal-dominant fashion, with the exception of 1 reported sporadic case.³

Research on HHS has primarily focused on genetic analyses of several affected families. Betz et al⁷ mapped the gene for HHS to band 6p21.3 in 2 families of Danish origin and in the Spanish family initially described by Toribio and Quinones.⁵ Three years later, a nonsense mutation in the CDSN gene encoding corneodesmosin was described.⁸ Despite these genetic advances, the pathogenesis of HHS and the role that corneodesmosin may play remain unclear.

Generalized forms of hypotrichosis (OMIM #605389) have long been reported and described as loss of scalp hair with involvement of eyebrows, eyelashes, and other body hair.⁹ Genetic studies have allowed for genome-wide linkage analysis, linking 3 families with this more generalized HHS phenotype to chromosome 18; specifically, an Italian family with sparse scalp and body hair but normal eyelashes and eyebrows,⁴ and 2 Pakistani families with thinning scalp hair and sparse truncal hair.¹⁰ A mutation in the APC downregulated 1 gene, APCDD1, also has been identified in these families.¹⁰ These genetic findings indicate that the generalized form of HHS is a distinct syndrome.

The differential diagnosis of HHS includes Marie-Unna hereditary hypotrichosis, loose anagen hair syndrome, trichothiodystrophy, and androgenetic alopecia. Marie-Unna hereditary hypotrichosis usually presents as near-complete absence of scalp hair at birth, development of wiry twisted hair in childhood, and progressive alopecia.³ Loose anagen hair syndrome usually demonstrates a ruffled cuticle on hair pull test and remits in late childhood. Polarization of the hair shaft can identify patients with trichothiodystrophy. Follicular miniaturization may lead one to consider early-onset androgenetic alopecia in some patients.

There is no effective treatment of HHS. Due to potential phenotypic variation, patients should be counseled that they may experience progressive or possible total loss of scalp hair by the third decade of life.^2,3,5 As with other hair loss disorders, wigs or additional over-the-counter cosmetic options may be considered.³ Currently, there are no known patient resources specific for HHS. Therefore, our patient’s family was referred to the National Alopecia Areata Foundation website (https://naaf.org/) for resources on discussing alopecia with school-aged children. The psychological impact of alopecia should not be overlooked and psychiatric referral should be provided, if needed. Examination of family members along with clinical monitoring are recommended. Genetic counseling also may be offered.³

The Diagnosis: Disseminate and Recurrent Infundibulofolliculitis

A punch biopsy of a representative lesion on the trunk was performed. Histopathologic examination revealed a chronic lymphohistiocytic proliferation, focal spongiosis, and lymphocytic exocytosis primarily involving the isthmus of the hair follicle (Figure 1). At the follicular opening there was associated parakeratosis of the adjacent epidermis (Figure 2). Given these clinical and histopathological findings, a diagnosis of disseminate and recurrent infundibulofolliculitis (DRIF) was made.

Disseminate and recurrent infundibulofolliculitis was first described by Hitch and Lund¹ in 1968 in a healthy 27-year-old black man as a widespread recurrent follicular eruption. Disseminate and recurrent infundibulofolliculitis usually affects young adult males with darkly pigmented skin.^2,3 It has less commonly been described in children, females, and white individuals.^3,4 Associations with atopy, systemic diseases, or medications are unknown.^3-6 The onset usually is sudden and the disease course may be characterized by intermittent recurrences. Pruritus usually is reported but may be mild.⁵

Histopathology is characterized by spongiosis centered on the infundibulum of the hair follicle and a primarily lymphocytic inflammatory infiltrate. Neutrophils also may be identified.³ Disseminate and recurrent infundibulofolliculitis can be differentiated histologically from clinically similar entities such as keratosis pilaris, which has a keratin plug filling the infundibulum; lichen nitidus, which is characterized by a clawlike downgrowth of the rete ridges surrounding a central foci of inflammation; or folliculitis, which is characterized by perifollicular suppurative inflammation.

Treatment of DRIF is anecdotal and limited to case reports. Vitamin A alone or in combination with vitamin E has been reported to lead to some improvement.⁵ Tetracycline-class antibiotics, keratolytics, antihistamines, and topical retinoids have not been successful, and mixed results have been seen with topical steroids.^5-7 There is a reported case of improvement with a 3-week regimen of psoralen plus UVA followed by twice-weekly maintenance.⁸ Promising results in the treatment of DRIF have been shown with oral isotretinoin once daily.^3-5 Finally, DRIF may resolve independently⁶; therefore, treatment of DRIF should be addressed on a case-by-case basis.

The Diagnosis: Disseminate and Recurrent Infundibulofolliculitis

A punch biopsy of a representative lesion on the trunk was performed. Histopathologic examination revealed a chronic lymphohistiocytic proliferation, focal spongiosis, and lymphocytic exocytosis primarily involving the isthmus of the hair follicle (Figure 1). At the follicular opening there was associated parakeratosis of the adjacent epidermis (Figure 2). Given these clinical and histopathological findings, a diagnosis of disseminate and recurrent infundibulofolliculitis (DRIF) was made.

Disseminate and recurrent infundibulofolliculitis was first described by Hitch and Lund¹ in 1968 in a healthy 27-year-old black man as a widespread recurrent follicular eruption. Disseminate and recurrent infundibulofolliculitis usually affects young adult males with darkly pigmented skin.^2,3 It has less commonly been described in children, females, and white individuals.^3,4 Associations with atopy, systemic diseases, or medications are unknown.^3-6 The onset usually is sudden and the disease course may be characterized by intermittent recurrences. Pruritus usually is reported but may be mild.⁵

Histopathology is characterized by spongiosis centered on the infundibulum of the hair follicle and a primarily lymphocytic inflammatory infiltrate. Neutrophils also may be identified.³ Disseminate and recurrent infundibulofolliculitis can be differentiated histologically from clinically similar entities such as keratosis pilaris, which has a keratin plug filling the infundibulum; lichen nitidus, which is characterized by a clawlike downgrowth of the rete ridges surrounding a central foci of inflammation; or folliculitis, which is characterized by perifollicular suppurative inflammation.

Treatment of DRIF is anecdotal and limited to case reports. Vitamin A alone or in combination with vitamin E has been reported to lead to some improvement.⁵ Tetracycline-class antibiotics, keratolytics, antihistamines, and topical retinoids have not been successful, and mixed results have been seen with topical steroids.^5-7 There is a reported case of improvement with a 3-week regimen of psoralen plus UVA followed by twice-weekly maintenance.⁸ Promising results in the treatment of DRIF have been shown with oral isotretinoin once daily.^3-5 Finally, DRIF may resolve independently⁶; therefore, treatment of DRIF should be addressed on a case-by-case basis.

The Diagnosis: Disseminate and Recurrent Infundibulofolliculitis

A punch biopsy of a representative lesion on the trunk was performed. Histopathologic examination revealed a chronic lymphohistiocytic proliferation, focal spongiosis, and lymphocytic exocytosis primarily involving the isthmus of the hair follicle (Figure 1). At the follicular opening there was associated parakeratosis of the adjacent epidermis (Figure 2). Given these clinical and histopathological findings, a diagnosis of disseminate and recurrent infundibulofolliculitis (DRIF) was made.

Disseminate and recurrent infundibulofolliculitis was first described by Hitch and Lund¹ in 1968 in a healthy 27-year-old black man as a widespread recurrent follicular eruption. Disseminate and recurrent infundibulofolliculitis usually affects young adult males with darkly pigmented skin.^2,3 It has less commonly been described in children, females, and white individuals.^3,4 Associations with atopy, systemic diseases, or medications are unknown.^3-6 The onset usually is sudden and the disease course may be characterized by intermittent recurrences. Pruritus usually is reported but may be mild.⁵

Histopathology is characterized by spongiosis centered on the infundibulum of the hair follicle and a primarily lymphocytic inflammatory infiltrate. Neutrophils also may be identified.³ Disseminate and recurrent infundibulofolliculitis can be differentiated histologically from clinically similar entities such as keratosis pilaris, which has a keratin plug filling the infundibulum; lichen nitidus, which is characterized by a clawlike downgrowth of the rete ridges surrounding a central foci of inflammation; or folliculitis, which is characterized by perifollicular suppurative inflammation.

Treatment of DRIF is anecdotal and limited to case reports. Vitamin A alone or in combination with vitamin E has been reported to lead to some improvement.⁵ Tetracycline-class antibiotics, keratolytics, antihistamines, and topical retinoids have not been successful, and mixed results have been seen with topical steroids.^5-7 There is a reported case of improvement with a 3-week regimen of psoralen plus UVA followed by twice-weekly maintenance.⁸ Promising results in the treatment of DRIF have been shown with oral isotretinoin once daily.^3-5 Finally, DRIF may resolve independently⁶; therefore, treatment of DRIF should be addressed on a case-by-case basis.

Pretibial myxedema (PM) is a cutaneous mucinosis associated with thyroid dysfunction. It most commonly presents in the setting of Graves disease and is seen less often in patients with hypothyroidism and euthyroidism.¹ The anterior tibia is most frequently affected, but lesions also may present on the feet, thighs, and upper extremities. Physical examination generally demonstrates skin thickening, hyperkeratosis, hyperpigmentation, yellow-red discoloration, and hyperhidrosis. Classically, the term peau d’orange has been used to characterize these clinical features.¹ Histologic examination of PM typically reveals marked deposition of mucin throughout the reticular dermis with sparing of the papillary dermis (Figure 1) and may be accompanied by overlying hyperkeratosis. Collagen fibers are splayed and appear decreased in density (Figure 2). Alcian blue, periodic acid–Schiff, colloidal iron, and toluidine blue staining can be used to highlight dermal mucin.

Figure 1. Prominent mucin deposition throughout the reticular dermis in pretibial myxedema (H&E, original magnification ×40).	Figure 2. Increased mucin deposition and collagen fiber splaying in pretibial myxedema (H&E, original magnification ×200).
Figure 3. Scleredema with increased dermal thickness (H&E, original magnification ×20) and interstitial mucin on colloidal iron–stained sections (inset in upper right corner, original magnification ×400).	Figure 4. Scleromyxedema with mucin deposition primarily in the superficial dermis as well as increased cellularity and fibrosis (H&E, original magnification ×200).
Figure 5. Nephrogenic systemic fibrosis with prominent mucinous fibrosis (H&E, original magnification ×40).	Figure 6. Tumid lupus erythematosus with a superficial and perivascular lymphoid infiltrate as well as increased dermal mucin (H&E, original magnification ×40).

Similar to PM, histologic examination of scleredema and scleromyxedema usually demonstrate prominent mucin deposition. In scleredema, mucin primarily is visualized in the deep dermis between thick collagen bundles and typically is localized to the back (Figure 3). Scleromyxedema is distinguished by mucin deposition in the superficial dermis with associated fibroblast proliferation and fibrosis (Figure 4).

Nephrogenic systemic fibrosis is characterized by proliferation of CD34⁺ dermal spindle cells, fibroblasts, interstitial mucin, altered elastic fibers, and thickened collagen bundles that involve the dermis and subcutaneous septa (Figure 5).² Tumid lupus erythematosus classically demonstrates perivascular and periadnexal superficial and deep lymphocytic inflammation (Figure 6). Similar to scleredema and PM, mucin deposition in tumid lupus erythematosus is interspersed between collagen bundles in the reticular dermis.³

Pretibial myxedema (PM) is a cutaneous mucinosis associated with thyroid dysfunction. It most commonly presents in the setting of Graves disease and is seen less often in patients with hypothyroidism and euthyroidism.¹ The anterior tibia is most frequently affected, but lesions also may present on the feet, thighs, and upper extremities. Physical examination generally demonstrates skin thickening, hyperkeratosis, hyperpigmentation, yellow-red discoloration, and hyperhidrosis. Classically, the term peau d’orange has been used to characterize these clinical features.¹ Histologic examination of PM typically reveals marked deposition of mucin throughout the reticular dermis with sparing of the papillary dermis (Figure 1) and may be accompanied by overlying hyperkeratosis. Collagen fibers are splayed and appear decreased in density (Figure 2). Alcian blue, periodic acid–Schiff, colloidal iron, and toluidine blue staining can be used to highlight dermal mucin.

Figure 1. Prominent mucin deposition throughout the reticular dermis in pretibial myxedema (H&E, original magnification ×40).	Figure 2. Increased mucin deposition and collagen fiber splaying in pretibial myxedema (H&E, original magnification ×200).
Figure 3. Scleredema with increased dermal thickness (H&E, original magnification ×20) and interstitial mucin on colloidal iron–stained sections (inset in upper right corner, original magnification ×400).	Figure 4. Scleromyxedema with mucin deposition primarily in the superficial dermis as well as increased cellularity and fibrosis (H&E, original magnification ×200).
Figure 5. Nephrogenic systemic fibrosis with prominent mucinous fibrosis (H&E, original magnification ×40).	Figure 6. Tumid lupus erythematosus with a superficial and perivascular lymphoid infiltrate as well as increased dermal mucin (H&E, original magnification ×40).

Similar to PM, histologic examination of scleredema and scleromyxedema usually demonstrate prominent mucin deposition. In scleredema, mucin primarily is visualized in the deep dermis between thick collagen bundles and typically is localized to the back (Figure 3). Scleromyxedema is distinguished by mucin deposition in the superficial dermis with associated fibroblast proliferation and fibrosis (Figure 4).

Nephrogenic systemic fibrosis is characterized by proliferation of CD34⁺ dermal spindle cells, fibroblasts, interstitial mucin, altered elastic fibers, and thickened collagen bundles that involve the dermis and subcutaneous septa (Figure 5).² Tumid lupus erythematosus classically demonstrates perivascular and periadnexal superficial and deep lymphocytic inflammation (Figure 6). Similar to scleredema and PM, mucin deposition in tumid lupus erythematosus is interspersed between collagen bundles in the reticular dermis.³

Pretibial myxedema (PM) is a cutaneous mucinosis associated with thyroid dysfunction. It most commonly presents in the setting of Graves disease and is seen less often in patients with hypothyroidism and euthyroidism.¹ The anterior tibia is most frequently affected, but lesions also may present on the feet, thighs, and upper extremities. Physical examination generally demonstrates skin thickening, hyperkeratosis, hyperpigmentation, yellow-red discoloration, and hyperhidrosis. Classically, the term peau d’orange has been used to characterize these clinical features.¹ Histologic examination of PM typically reveals marked deposition of mucin throughout the reticular dermis with sparing of the papillary dermis (Figure 1) and may be accompanied by overlying hyperkeratosis. Collagen fibers are splayed and appear decreased in density (Figure 2). Alcian blue, periodic acid–Schiff, colloidal iron, and toluidine blue staining can be used to highlight dermal mucin.

Figure 1. Prominent mucin deposition throughout the reticular dermis in pretibial myxedema (H&E, original magnification ×40).	Figure 2. Increased mucin deposition and collagen fiber splaying in pretibial myxedema (H&E, original magnification ×200).
Figure 3. Scleredema with increased dermal thickness (H&E, original magnification ×20) and interstitial mucin on colloidal iron–stained sections (inset in upper right corner, original magnification ×400).	Figure 4. Scleromyxedema with mucin deposition primarily in the superficial dermis as well as increased cellularity and fibrosis (H&E, original magnification ×200).
Figure 5. Nephrogenic systemic fibrosis with prominent mucinous fibrosis (H&E, original magnification ×40).	Figure 6. Tumid lupus erythematosus with a superficial and perivascular lymphoid infiltrate as well as increased dermal mucin (H&E, original magnification ×40).

Similar to PM, histologic examination of scleredema and scleromyxedema usually demonstrate prominent mucin deposition. In scleredema, mucin primarily is visualized in the deep dermis between thick collagen bundles and typically is localized to the back (Figure 3). Scleromyxedema is distinguished by mucin deposition in the superficial dermis with associated fibroblast proliferation and fibrosis (Figure 4).

Nephrogenic systemic fibrosis is characterized by proliferation of CD34⁺ dermal spindle cells, fibroblasts, interstitial mucin, altered elastic fibers, and thickened collagen bundles that involve the dermis and subcutaneous septa (Figure 5).² Tumid lupus erythematosus classically demonstrates perivascular and periadnexal superficial and deep lymphocytic inflammation (Figure 6). Similar to scleredema and PM, mucin deposition in tumid lupus erythematosus is interspersed between collagen bundles in the reticular dermis.³