Hair & Nails

The Diagnosis: Onychomadesis Following Hand-foot-and-mouth Disease

In 1846, Joseph Honoré Simon Beau described specific diagnostic signs manifested in the nails during various disease states.¹ He suggested that the width of the nail plate depression correlated with the duration of illness. Since then, the correlation of nail changes during times of illness has been confirmed. The term Beau lines currently is used to describe transverse ridging of the nail plate due to transient arrest in nail plate formation.¹ Onychomadesis is believed to be an extreme form of Beau lines in which the whole thickness of the nail plate is affected, resulting in its separation from the proximal nail fold and shedding of the nail plate.

Nail plate detachment in onychomadesis is due to a severe insult that results in complete arrest of the nail matrix activity. Onychomadesis has a wide spectrum of clinical presentations, ranging from mild transverse ridges of the nail plate (Beau lines) to complete nail shedding.² Trauma is the leading cause of single-digit onychomadesis, while multiple-digit onychomadesis usually is caused by a systemic disease (eg, blistering illnesses). Cases of multiple-nail onychomadesis have been reported following hand-foot-and-mouth disease (HFMD), though the majority of cases of HFMD do not present with onychomadesis.

Hand-foot-and-mouth disease is most commonly caused by 2 types of intestinal strains of Human enterovirus A: (1) coxsackievirus A6 (CVA6) or A16 (CVA16) and (2) enterovirus 71.^3,4 Symptoms of HFMD include fever and sore throat followed by the development of oral ulcerations 1 to 2 days later. A vesicular or maculopapular rash can then develop on the hands, feet, and mouth. Complications following HFMD are rare but can include encephalitis, meningitis, and pneumonia. Symptoms typically resolve after 6 days without any treatment.³

A cluster of onychomadesis cases following HFMD outbreaks have been reported in Europe, Asia, and the United States. In some reports, causative viral strains have been identified. After a national HFMD outbreak in Finland in fall 2008, investigators isolated strains of CVA6 in the shedded nails of sibling patients.⁴ The CVA6 strain was found to be the primary pathogen causing that particular HFMD outbreak and onychomadesis was a hallmark presentation of this viral epidemic. Previously, HFMD outbreaks were known to be caused by CVA16 or enterovirus 71, with enterovirus 71 strains occurring mostly in Southeast Asia and Australia.⁴ In a report from Taiwan, the incidence of onychomadesis after CVA6 infection was 37% (48/130) as compared to 5% (7/145) in cases with non-CVA6 causative strains. Among patients with onychomadesis, 69% (33/48) were reported to experience concurrent palmoplantar desquamation before or during presentation of nail changes.⁵

Another Finnish study investigated an atypical outbreak of HFMD that occurred primarily in adult patients.⁶ Many of these patients also had onychomadesis several weeks following HFMD. Of 317 cases, human enteroviruses were detected in specimens from 212 cases (67%), including both children and adults. Two human enterovirus types—CVA6 (71% [83/117]) and coxsackievirus A10 (28% [33/117])—were identified as the causative agents of the outbreak. One genetic variant of CVA6 predominated, but 3 other genetically distinct CVA6 strains also were found.⁶ The 2008 HFMD outbreak in Finland was found to be caused by 2 concomitantly circulating human enteroviruses, which up until now have been infrequently detected together as causative agents of HFMD. Onychomadesis was a common occurrence in the Finnish HFMD outbreak, which has been previously linked to CVA6. The co-circulation of CVA6 and coxsackievirus A10 suggests an endemic emergence of new genetic variants of these enteroviruses.⁶

There also have been several reports of onychomadesis outbreaks in Spain, 2 of which occurred in nursery settings. One report noted that patients with a history of HFMD were 14 times more likely to develop onychomadesis (relative risk, 14; 95% confidence interval, 4.57-42.86).³ There also was a noted difference in prevalence of onychomadesis regarding age: a 55% (18/33) occurrence rate was noted in the youngest age group (9–23 months), 30% (8/27) in the middle age group (24–32 months), and 4% (1/28) in the oldest age group (33–42 months). Occurrence of onychomadesis and nail plate changes was observed on average 40 days after HFMD, and an average of 4 nails were shed per case.³ A report investigating a separate HFMD outbreak in Spain found a high percentage of onychomadesis (96% [298/311]) occurring in children younger than 6 years. This outbreak, which occurred in the metropolitan area of Valencia, was associated with an outbreak of HFMD primarily caused by coxsackievirus A10.⁷ A third Spanish study uncovered a high occurrence of onychomadesis in a nursery setting as a consequence of HFMD, where 92% (11/12) of onychomadesis cases were preceded by HFMD 2 months prior.⁸

A case series reported in Chicago, Illinois, in the late 1990s identified 5 pediatric patients with HFMD associated with Beau lines and onychomadesis.¹ Only 3 of 5 (60%) patients had a fever; therefore, fever-induced nail matrix arrest was ruled out as the inciting factor of the nail changes seen. All patients were given over-the-counter analgesics and 2 received antibiotics (amoxicillin for the first 48 hours). None of these medications have been implicated as plausible causes of nail matrix arrest. Two patients were siblings and the rest were not related. None of the patients had a history of close physical proximity (eg, attendance at the same day care or school). All 5 patients developed HFMD within 4 weeks of one another, and all were from the suburbs of Chicago (with 4 of 5 [80%] patients living within a 60-mile radius of each other). Although the causative viral strain was not isolated, the authors concluded that all the patients were likely to have been infected by the same virus due to the general vicinity of the patients to each other. Furthermore, the collective case reports likely represented an HFMD epidemic caused by a particular strain that can induce onychomadesis.¹

Supportive care for the viral illness paired with protection of the nail bed until new nail growth occurs is ideal, which requires maintaining short nails and using adhesive bandages over the affected nails to avoid snagging the nail or ripping off the partially attached nails.

Onychomadesis can follow HFMD, especially in cases caused by CVA6. Cases of onychomadesis are mild and self-limited. When onychomadesis is noted, historical review of viral illnesses within 1 to 2 months prior to nail changes often will identify the causative disease.

The Diagnosis: Onychomadesis Following Hand-foot-and-mouth Disease

In 1846, Joseph Honoré Simon Beau described specific diagnostic signs manifested in the nails during various disease states.¹ He suggested that the width of the nail plate depression correlated with the duration of illness. Since then, the correlation of nail changes during times of illness has been confirmed. The term Beau lines currently is used to describe transverse ridging of the nail plate due to transient arrest in nail plate formation.¹ Onychomadesis is believed to be an extreme form of Beau lines in which the whole thickness of the nail plate is affected, resulting in its separation from the proximal nail fold and shedding of the nail plate.

Nail plate detachment in onychomadesis is due to a severe insult that results in complete arrest of the nail matrix activity. Onychomadesis has a wide spectrum of clinical presentations, ranging from mild transverse ridges of the nail plate (Beau lines) to complete nail shedding.² Trauma is the leading cause of single-digit onychomadesis, while multiple-digit onychomadesis usually is caused by a systemic disease (eg, blistering illnesses). Cases of multiple-nail onychomadesis have been reported following hand-foot-and-mouth disease (HFMD), though the majority of cases of HFMD do not present with onychomadesis.

Hand-foot-and-mouth disease is most commonly caused by 2 types of intestinal strains of Human enterovirus A: (1) coxsackievirus A6 (CVA6) or A16 (CVA16) and (2) enterovirus 71.^3,4 Symptoms of HFMD include fever and sore throat followed by the development of oral ulcerations 1 to 2 days later. A vesicular or maculopapular rash can then develop on the hands, feet, and mouth. Complications following HFMD are rare but can include encephalitis, meningitis, and pneumonia. Symptoms typically resolve after 6 days without any treatment.³

A cluster of onychomadesis cases following HFMD outbreaks have been reported in Europe, Asia, and the United States. In some reports, causative viral strains have been identified. After a national HFMD outbreak in Finland in fall 2008, investigators isolated strains of CVA6 in the shedded nails of sibling patients.⁴ The CVA6 strain was found to be the primary pathogen causing that particular HFMD outbreak and onychomadesis was a hallmark presentation of this viral epidemic. Previously, HFMD outbreaks were known to be caused by CVA16 or enterovirus 71, with enterovirus 71 strains occurring mostly in Southeast Asia and Australia.⁴ In a report from Taiwan, the incidence of onychomadesis after CVA6 infection was 37% (48/130) as compared to 5% (7/145) in cases with non-CVA6 causative strains. Among patients with onychomadesis, 69% (33/48) were reported to experience concurrent palmoplantar desquamation before or during presentation of nail changes.⁵

Another Finnish study investigated an atypical outbreak of HFMD that occurred primarily in adult patients.⁶ Many of these patients also had onychomadesis several weeks following HFMD. Of 317 cases, human enteroviruses were detected in specimens from 212 cases (67%), including both children and adults. Two human enterovirus types—CVA6 (71% [83/117]) and coxsackievirus A10 (28% [33/117])—were identified as the causative agents of the outbreak. One genetic variant of CVA6 predominated, but 3 other genetically distinct CVA6 strains also were found.⁶ The 2008 HFMD outbreak in Finland was found to be caused by 2 concomitantly circulating human enteroviruses, which up until now have been infrequently detected together as causative agents of HFMD. Onychomadesis was a common occurrence in the Finnish HFMD outbreak, which has been previously linked to CVA6. The co-circulation of CVA6 and coxsackievirus A10 suggests an endemic emergence of new genetic variants of these enteroviruses.⁶

There also have been several reports of onychomadesis outbreaks in Spain, 2 of which occurred in nursery settings. One report noted that patients with a history of HFMD were 14 times more likely to develop onychomadesis (relative risk, 14; 95% confidence interval, 4.57-42.86).³ There also was a noted difference in prevalence of onychomadesis regarding age: a 55% (18/33) occurrence rate was noted in the youngest age group (9–23 months), 30% (8/27) in the middle age group (24–32 months), and 4% (1/28) in the oldest age group (33–42 months). Occurrence of onychomadesis and nail plate changes was observed on average 40 days after HFMD, and an average of 4 nails were shed per case.³ A report investigating a separate HFMD outbreak in Spain found a high percentage of onychomadesis (96% [298/311]) occurring in children younger than 6 years. This outbreak, which occurred in the metropolitan area of Valencia, was associated with an outbreak of HFMD primarily caused by coxsackievirus A10.⁷ A third Spanish study uncovered a high occurrence of onychomadesis in a nursery setting as a consequence of HFMD, where 92% (11/12) of onychomadesis cases were preceded by HFMD 2 months prior.⁸

A case series reported in Chicago, Illinois, in the late 1990s identified 5 pediatric patients with HFMD associated with Beau lines and onychomadesis.¹ Only 3 of 5 (60%) patients had a fever; therefore, fever-induced nail matrix arrest was ruled out as the inciting factor of the nail changes seen. All patients were given over-the-counter analgesics and 2 received antibiotics (amoxicillin for the first 48 hours). None of these medications have been implicated as plausible causes of nail matrix arrest. Two patients were siblings and the rest were not related. None of the patients had a history of close physical proximity (eg, attendance at the same day care or school). All 5 patients developed HFMD within 4 weeks of one another, and all were from the suburbs of Chicago (with 4 of 5 [80%] patients living within a 60-mile radius of each other). Although the causative viral strain was not isolated, the authors concluded that all the patients were likely to have been infected by the same virus due to the general vicinity of the patients to each other. Furthermore, the collective case reports likely represented an HFMD epidemic caused by a particular strain that can induce onychomadesis.¹

Supportive care for the viral illness paired with protection of the nail bed until new nail growth occurs is ideal, which requires maintaining short nails and using adhesive bandages over the affected nails to avoid snagging the nail or ripping off the partially attached nails.

Onychomadesis can follow HFMD, especially in cases caused by CVA6. Cases of onychomadesis are mild and self-limited. When onychomadesis is noted, historical review of viral illnesses within 1 to 2 months prior to nail changes often will identify the causative disease.

The Diagnosis: Onychomadesis Following Hand-foot-and-mouth Disease

In 1846, Joseph Honoré Simon Beau described specific diagnostic signs manifested in the nails during various disease states.¹ He suggested that the width of the nail plate depression correlated with the duration of illness. Since then, the correlation of nail changes during times of illness has been confirmed. The term Beau lines currently is used to describe transverse ridging of the nail plate due to transient arrest in nail plate formation.¹ Onychomadesis is believed to be an extreme form of Beau lines in which the whole thickness of the nail plate is affected, resulting in its separation from the proximal nail fold and shedding of the nail plate.

Nail plate detachment in onychomadesis is due to a severe insult that results in complete arrest of the nail matrix activity. Onychomadesis has a wide spectrum of clinical presentations, ranging from mild transverse ridges of the nail plate (Beau lines) to complete nail shedding.² Trauma is the leading cause of single-digit onychomadesis, while multiple-digit onychomadesis usually is caused by a systemic disease (eg, blistering illnesses). Cases of multiple-nail onychomadesis have been reported following hand-foot-and-mouth disease (HFMD), though the majority of cases of HFMD do not present with onychomadesis.

Hand-foot-and-mouth disease is most commonly caused by 2 types of intestinal strains of Human enterovirus A: (1) coxsackievirus A6 (CVA6) or A16 (CVA16) and (2) enterovirus 71.^3,4 Symptoms of HFMD include fever and sore throat followed by the development of oral ulcerations 1 to 2 days later. A vesicular or maculopapular rash can then develop on the hands, feet, and mouth. Complications following HFMD are rare but can include encephalitis, meningitis, and pneumonia. Symptoms typically resolve after 6 days without any treatment.³

A cluster of onychomadesis cases following HFMD outbreaks have been reported in Europe, Asia, and the United States. In some reports, causative viral strains have been identified. After a national HFMD outbreak in Finland in fall 2008, investigators isolated strains of CVA6 in the shedded nails of sibling patients.⁴ The CVA6 strain was found to be the primary pathogen causing that particular HFMD outbreak and onychomadesis was a hallmark presentation of this viral epidemic. Previously, HFMD outbreaks were known to be caused by CVA16 or enterovirus 71, with enterovirus 71 strains occurring mostly in Southeast Asia and Australia.⁴ In a report from Taiwan, the incidence of onychomadesis after CVA6 infection was 37% (48/130) as compared to 5% (7/145) in cases with non-CVA6 causative strains. Among patients with onychomadesis, 69% (33/48) were reported to experience concurrent palmoplantar desquamation before or during presentation of nail changes.⁵

Another Finnish study investigated an atypical outbreak of HFMD that occurred primarily in adult patients.⁶ Many of these patients also had onychomadesis several weeks following HFMD. Of 317 cases, human enteroviruses were detected in specimens from 212 cases (67%), including both children and adults. Two human enterovirus types—CVA6 (71% [83/117]) and coxsackievirus A10 (28% [33/117])—were identified as the causative agents of the outbreak. One genetic variant of CVA6 predominated, but 3 other genetically distinct CVA6 strains also were found.⁶ The 2008 HFMD outbreak in Finland was found to be caused by 2 concomitantly circulating human enteroviruses, which up until now have been infrequently detected together as causative agents of HFMD. Onychomadesis was a common occurrence in the Finnish HFMD outbreak, which has been previously linked to CVA6. The co-circulation of CVA6 and coxsackievirus A10 suggests an endemic emergence of new genetic variants of these enteroviruses.⁶

There also have been several reports of onychomadesis outbreaks in Spain, 2 of which occurred in nursery settings. One report noted that patients with a history of HFMD were 14 times more likely to develop onychomadesis (relative risk, 14; 95% confidence interval, 4.57-42.86).³ There also was a noted difference in prevalence of onychomadesis regarding age: a 55% (18/33) occurrence rate was noted in the youngest age group (9–23 months), 30% (8/27) in the middle age group (24–32 months), and 4% (1/28) in the oldest age group (33–42 months). Occurrence of onychomadesis and nail plate changes was observed on average 40 days after HFMD, and an average of 4 nails were shed per case.³ A report investigating a separate HFMD outbreak in Spain found a high percentage of onychomadesis (96% [298/311]) occurring in children younger than 6 years. This outbreak, which occurred in the metropolitan area of Valencia, was associated with an outbreak of HFMD primarily caused by coxsackievirus A10.⁷ A third Spanish study uncovered a high occurrence of onychomadesis in a nursery setting as a consequence of HFMD, where 92% (11/12) of onychomadesis cases were preceded by HFMD 2 months prior.⁸

A case series reported in Chicago, Illinois, in the late 1990s identified 5 pediatric patients with HFMD associated with Beau lines and onychomadesis.¹ Only 3 of 5 (60%) patients had a fever; therefore, fever-induced nail matrix arrest was ruled out as the inciting factor of the nail changes seen. All patients were given over-the-counter analgesics and 2 received antibiotics (amoxicillin for the first 48 hours). None of these medications have been implicated as plausible causes of nail matrix arrest. Two patients were siblings and the rest were not related. None of the patients had a history of close physical proximity (eg, attendance at the same day care or school). All 5 patients developed HFMD within 4 weeks of one another, and all were from the suburbs of Chicago (with 4 of 5 [80%] patients living within a 60-mile radius of each other). Although the causative viral strain was not isolated, the authors concluded that all the patients were likely to have been infected by the same virus due to the general vicinity of the patients to each other. Furthermore, the collective case reports likely represented an HFMD epidemic caused by a particular strain that can induce onychomadesis.¹

Supportive care for the viral illness paired with protection of the nail bed until new nail growth occurs is ideal, which requires maintaining short nails and using adhesive bandages over the affected nails to avoid snagging the nail or ripping off the partially attached nails.

Onychomadesis can follow HFMD, especially in cases caused by CVA6. Cases of onychomadesis are mild and self-limited. When onychomadesis is noted, historical review of viral illnesses within 1 to 2 months prior to nail changes often will identify the causative disease.

The Diagnosis: Subungual Eccrine Poroma

Histologic examination revealed a solitary papule (Figure 1). The epidermis was replaced with a well-defined proliferation of cuboidal and poroid cells. These cells demonstrated a downgrowth into the dermis in broad anastomosing bands that were surrounded by a fibrovascular stroma. Notably, there were few scattered foci of maturation into the ductal lumina of eccrine origin, which confirmed the diagnosis (Figure 2).

Figure 1. A solitary papule consisting of a proliferation of cuboidal and poroid cells (H&E, original magnification ×4). Figure 2. Scattered foci of maturation into the ductal lumina of eccrine origin (H&E, original magnification ×10).

First described in 1956 by Goldman et al,¹ eccrine poromas are benign, slow-growing tumors that account for approximately 10% of sweat gland neoplasms.² Onset is typically in mid to late adulthood, and there is no ethnic or gender predilection. Classically, eccrine poromas present as soft, sessile, reddish papules or nodules measuring less than 2 cm that protrude from a well-circumscribed depression.

Although eccrine poromas can develop on hair-bearing regions, they most commonly arise on acral skin. In acral locations, bleeding, discharge, rapid growth, and localized pain can occur. These symptoms are even more common in this lesion’s malignant counterpart, eccrine porocarcinoma.³

Solar damage, radiation exposure, trauma, and human papillomavirus have been indicated in the pathogenesis of eccrine poroma; however, the exact etiology has yet to be defined.^2,4 The differential diagnosis includes nevus, pyogenic granu-loma, acrochordon, basal cell carcinoma, and verruca vulgaris.⁵

Histologically, eccrine poromas consist of a combination of 5 distinct features: poroid cells, cuticular cells, intracytoplasmic or intercellular vacuolization en route to duct formation, massive necrosis or necrosis en masse, and nuclear monomorphism of the poroid and cuticular cells.⁶ However, all 5 histologic features do not have to be present for the diagnosis. Classically, there is a sharp demarcation of the lesion from the surrounding epidermis.⁷

Treatment of choice is complete excision to prevent recurrence and risk for malignant transformation in long-standing lesions. One study of eccrine porocarcinomas found that 18% (11/62) arose from a benign preexistent poroma.⁸ These malignant lesions are found more commonly on the extremities and tend to show a slight female predominance.⁹

Although there have been 2 reported cases of subungual eccrine porocarcinomas^9,10 and 1 case of periungual eccrine porocarcinoma,¹¹ according to an Ovid search using the terms porocarcinoma and nail, the benign subungual eccrine poroma is more rare.

The Diagnosis: Subungual Eccrine Poroma

Histologic examination revealed a solitary papule (Figure 1). The epidermis was replaced with a well-defined proliferation of cuboidal and poroid cells. These cells demonstrated a downgrowth into the dermis in broad anastomosing bands that were surrounded by a fibrovascular stroma. Notably, there were few scattered foci of maturation into the ductal lumina of eccrine origin, which confirmed the diagnosis (Figure 2).

Figure 1. A solitary papule consisting of a proliferation of cuboidal and poroid cells (H&E, original magnification ×4). Figure 2. Scattered foci of maturation into the ductal lumina of eccrine origin (H&E, original magnification ×10).

First described in 1956 by Goldman et al,¹ eccrine poromas are benign, slow-growing tumors that account for approximately 10% of sweat gland neoplasms.² Onset is typically in mid to late adulthood, and there is no ethnic or gender predilection. Classically, eccrine poromas present as soft, sessile, reddish papules or nodules measuring less than 2 cm that protrude from a well-circumscribed depression.

Although eccrine poromas can develop on hair-bearing regions, they most commonly arise on acral skin. In acral locations, bleeding, discharge, rapid growth, and localized pain can occur. These symptoms are even more common in this lesion’s malignant counterpart, eccrine porocarcinoma.³

Solar damage, radiation exposure, trauma, and human papillomavirus have been indicated in the pathogenesis of eccrine poroma; however, the exact etiology has yet to be defined.^2,4 The differential diagnosis includes nevus, pyogenic granu-loma, acrochordon, basal cell carcinoma, and verruca vulgaris.⁵

Histologically, eccrine poromas consist of a combination of 5 distinct features: poroid cells, cuticular cells, intracytoplasmic or intercellular vacuolization en route to duct formation, massive necrosis or necrosis en masse, and nuclear monomorphism of the poroid and cuticular cells.⁶ However, all 5 histologic features do not have to be present for the diagnosis. Classically, there is a sharp demarcation of the lesion from the surrounding epidermis.⁷

Treatment of choice is complete excision to prevent recurrence and risk for malignant transformation in long-standing lesions. One study of eccrine porocarcinomas found that 18% (11/62) arose from a benign preexistent poroma.⁸ These malignant lesions are found more commonly on the extremities and tend to show a slight female predominance.⁹

Although there have been 2 reported cases of subungual eccrine porocarcinomas^9,10 and 1 case of periungual eccrine porocarcinoma,¹¹ according to an Ovid search using the terms porocarcinoma and nail, the benign subungual eccrine poroma is more rare.

The Diagnosis: Subungual Eccrine Poroma

Histologic examination revealed a solitary papule (Figure 1). The epidermis was replaced with a well-defined proliferation of cuboidal and poroid cells. These cells demonstrated a downgrowth into the dermis in broad anastomosing bands that were surrounded by a fibrovascular stroma. Notably, there were few scattered foci of maturation into the ductal lumina of eccrine origin, which confirmed the diagnosis (Figure 2).

Figure 1. A solitary papule consisting of a proliferation of cuboidal and poroid cells (H&E, original magnification ×4). Figure 2. Scattered foci of maturation into the ductal lumina of eccrine origin (H&E, original magnification ×10).

First described in 1956 by Goldman et al,¹ eccrine poromas are benign, slow-growing tumors that account for approximately 10% of sweat gland neoplasms.² Onset is typically in mid to late adulthood, and there is no ethnic or gender predilection. Classically, eccrine poromas present as soft, sessile, reddish papules or nodules measuring less than 2 cm that protrude from a well-circumscribed depression.

Although eccrine poromas can develop on hair-bearing regions, they most commonly arise on acral skin. In acral locations, bleeding, discharge, rapid growth, and localized pain can occur. These symptoms are even more common in this lesion’s malignant counterpart, eccrine porocarcinoma.³

Solar damage, radiation exposure, trauma, and human papillomavirus have been indicated in the pathogenesis of eccrine poroma; however, the exact etiology has yet to be defined.^2,4 The differential diagnosis includes nevus, pyogenic granu-loma, acrochordon, basal cell carcinoma, and verruca vulgaris.⁵

Histologically, eccrine poromas consist of a combination of 5 distinct features: poroid cells, cuticular cells, intracytoplasmic or intercellular vacuolization en route to duct formation, massive necrosis or necrosis en masse, and nuclear monomorphism of the poroid and cuticular cells.⁶ However, all 5 histologic features do not have to be present for the diagnosis. Classically, there is a sharp demarcation of the lesion from the surrounding epidermis.⁷

Treatment of choice is complete excision to prevent recurrence and risk for malignant transformation in long-standing lesions. One study of eccrine porocarcinomas found that 18% (11/62) arose from a benign preexistent poroma.⁸ These malignant lesions are found more commonly on the extremities and tend to show a slight female predominance.⁹

Although there have been 2 reported cases of subungual eccrine porocarcinomas^9,10 and 1 case of periungual eccrine porocarcinoma,¹¹ according to an Ovid search using the terms porocarcinoma and nail, the benign subungual eccrine poroma is more rare.

The Diagnosis: “Pseudonits”

Dreadlocks are matted hairs formed into thick ropelike strands (Figure 1). As a chosen hairstyle dreadlocks are worn by individuals of many different ethnic groups but are most commonly associated with members of the Rastafarian movement, or Rastas. Various techniques are used to form dreadlocks including backcombing (also known as teasing) in which the hair is combed toward the scalp to facilitate tangles and knotting or the neglect method in which the hair is not combed, brushed, or cut, becoming tangled and twisted as it grows long. Manicuring and perming techniques may be used to create the starting point for dreadlocks.

Figure 1. Dreadlocks are matted hairs formed into thick ropelike strands.

Telogen hairs are the hairs shed as part of normal hair cycling. The average person is estimated to lose 50 telogen hairs per day.¹ With dreadlocks, the hairs are entangled distally, so when telogen hairs are released from scalp follicles, the shed hairs remain part of the locks. These “club” hairs have a bulbous white tip situated at the proximal end of the hair shaft (Figure 2) and should not be mistaken for the eggs of Pediculus humanus var capitis, hence the designation pseudonits.² Hair casts, keratinous material surrounding the hair shafts when there is infundibular or perifollicular hyperkeratosis, also may resemble nits.³ Hair cast pseudonits can be distinguished from true nits by one’s ability to slide the hair casts freely along the hair shaft, whereas lice ova are cemented to the hair shaft and fixed in place.

The Diagnosis: “Pseudonits”

Dreadlocks are matted hairs formed into thick ropelike strands (Figure 1). As a chosen hairstyle dreadlocks are worn by individuals of many different ethnic groups but are most commonly associated with members of the Rastafarian movement, or Rastas. Various techniques are used to form dreadlocks including backcombing (also known as teasing) in which the hair is combed toward the scalp to facilitate tangles and knotting or the neglect method in which the hair is not combed, brushed, or cut, becoming tangled and twisted as it grows long. Manicuring and perming techniques may be used to create the starting point for dreadlocks.

Figure 1. Dreadlocks are matted hairs formed into thick ropelike strands.

Telogen hairs are the hairs shed as part of normal hair cycling. The average person is estimated to lose 50 telogen hairs per day.¹ With dreadlocks, the hairs are entangled distally, so when telogen hairs are released from scalp follicles, the shed hairs remain part of the locks. These “club” hairs have a bulbous white tip situated at the proximal end of the hair shaft (Figure 2) and should not be mistaken for the eggs of Pediculus humanus var capitis, hence the designation pseudonits.² Hair casts, keratinous material surrounding the hair shafts when there is infundibular or perifollicular hyperkeratosis, also may resemble nits.³ Hair cast pseudonits can be distinguished from true nits by one’s ability to slide the hair casts freely along the hair shaft, whereas lice ova are cemented to the hair shaft and fixed in place.

The Diagnosis: “Pseudonits”

Dreadlocks are matted hairs formed into thick ropelike strands (Figure 1). As a chosen hairstyle dreadlocks are worn by individuals of many different ethnic groups but are most commonly associated with members of the Rastafarian movement, or Rastas. Various techniques are used to form dreadlocks including backcombing (also known as teasing) in which the hair is combed toward the scalp to facilitate tangles and knotting or the neglect method in which the hair is not combed, brushed, or cut, becoming tangled and twisted as it grows long. Manicuring and perming techniques may be used to create the starting point for dreadlocks.

Figure 1. Dreadlocks are matted hairs formed into thick ropelike strands.

Telogen hairs are the hairs shed as part of normal hair cycling. The average person is estimated to lose 50 telogen hairs per day.¹ With dreadlocks, the hairs are entangled distally, so when telogen hairs are released from scalp follicles, the shed hairs remain part of the locks. These “club” hairs have a bulbous white tip situated at the proximal end of the hair shaft (Figure 2) and should not be mistaken for the eggs of Pediculus humanus var capitis, hence the designation pseudonits.² Hair casts, keratinous material surrounding the hair shafts when there is infundibular or perifollicular hyperkeratosis, also may resemble nits.³ Hair cast pseudonits can be distinguished from true nits by one’s ability to slide the hair casts freely along the hair shaft, whereas lice ova are cemented to the hair shaft and fixed in place.

Onychomycosis is a common progressive infection of the nails caused by dermatophytes, nondermatophyte molds, and yeasts, with Trichophyton rubrum being the most common causative organism.^1-3 Onychomycosis affects approximately 2% to 26% of different populations worldwide. It represents 20% to 50% of onychopathies and approximately 30% of fungal cutaneous infections.^4-9 Less than 30% of infected persons seek medical advice or treatment even in developed areas of the world.¹⁰ Onychomycosis may be a source of more widespread fungal skin infections or give rise to complications such as cellulitis. Chronic, long-lasting infection may result in nail dystrophy and can lead to pain, absence from work, and decreased quality of life.^1,11 Because the dermatophyte can contaminate communal bathing facilities and spread to others,¹² it is important to effectively target and treat patients with onychomycosis, thus reducing the rate of related morbidities.^1,9

The primary aim of onychomycosis treatment is to cure the infection and prevent relapse. Both topical and oral agents are available for the treatment of fungal nail infections. Generally, systemic therapy for onychomycosis is more successful than topical treatment, likely due to poor penetration of topical medications into the nail plate.^1,2,9 However, newer topical drugs have shown promising results in treating some types of onychomycosis.¹³ In its guidelines for treatment of onychomycosis, the British Association of Dermatologists recommends use of topical treatment under the following conditions: (1) when there is not extensive involvement of the nail plate (eg, candidal paronychia, superficial white onychomycosis, early stages of distal and lateral subungual onychomycosis), (2) when systemic therapy is contraindicated, or (3) in combination with systemic therapy.¹ Although there are multiple treatments for fungal nail infections, there are limited reports on the ways in which physicians actually use these treatments or the frequency with which they prescribe them.

This study provides a representative portrayal of onychomycosis visits in the US outpatient setting using a large nationally sampled survey. In particular, we aimed to assess the number of visits related to onychomycosis, the demographics of patients, and the treatments being prescribed for onychomycosis.

Methods

Study Design

Data from January 1, 1993, to December 31, 2010, were collected from the National Ambulatory Medical Care Survey (NAMCS), an ongoing survey of nonfederal employed US office-based physicians who are primarily engaged in direct patient care. The NAMCS has been conducted by the National Center for Health Statistics every year since 1989 to estimate the utilization of ambulatory care services in the United States. Since 1989 including 1993 to 2010, the NAMCS sampled approximately 30,000 visits per year. For each visit sampled, a 1-page patient log including demographic data, physicians’ diagnoses, services provided, and medications was completed. In the NAMCS survey, visits were divided into 2 groups: (1) visits from established patients that have been seen in that office before for any reason, and (2) visits for new (ie, first-time) patients. The current study included all visits in which fungal nail infection (code 110.1 according to the International Classification of Diseases, Ninth Revision [ICD-9]) was listed as 1 of 3 possible diagnoses.

Statistical Analysis

Sampling weights were applied to data to produce estimates for the total US outpatient setting.¹⁴ Data were analyzed using SAS version 9.2, and SAS survey analysis procedures were used to account for the clustered sampling of the survey. The total numbers of visits for which onychomycosis was 1 of 3 possible diagnoses and for which it was the sole diagnosis were reported. Visit rates per population by demographic characteristics (ie, patient sex, age, race, and ethnicity) were calculated. Population estimates were based on the 2001 NAMCS Public Micro-Data File Documentation records of the US census estimates for noninstitutionalized civilian persons.¹⁵ Trends in proportion of visits linked with an onychomycosis diagnosis over time were evaluated using the SAS SURVEYREG procedure. Types of physicians who attended to these visits as well as leading comorbidities that had been diagnosed and documented in the medical record were characterized. Onychomycosis-related medications prescribed at these visits were reported and prescribing trends over time were evaluated. Differences in the treatment prescribed according to the type of visit (ie, first-time or return visit); physician specialty; and patients’ gender, race, and health conditions (eg, obesity, diabetes mellitus) were examined. To exclude the possibility that fluconazole and other broad-spectrum antifungals were being used for secondary diagnoses, we determined the number of visits that had an additional diagnosis of either candidiasis (ICD-9 codes 112.0–112.9) or “other specified erythematous conditions” (ICD-9 code 695.89).

Results

During the 18-year study period, 636 visits with a diagnosis of onychomycosis were recorded in the NAMCS database. This unweighted number of visits corresponded with approximately 19,350,000 visits (an average of 1,075,000 visits per year) to physicians’ offices with a diagnosis of onychomycosis in the United States during this period. Among these visits, there were an estimated 4,250,000 visits with fungal nail infection as the only diagnosis (no other comorbidities recorded). The recorded visits included more female (57.6%) than male (42.4%) patients, and 85% of patients were white (Table). Patients aged 35 to 44 years accounted for the largest number of visits; however, the estimated rate of onychomycosis visits per 100,000 US citizens was highest among those aged 65 to 74 years (Figure 1).

Figure 1. Health care utilization for onychomycosis from 1993 to 2010 stratified by patient age, as defined as: (1) the total estimated number of US outpatient visits that included a diagnosis of onychomycosis (right-hand y axis and blue bars), and (2) the estimated number of visits per 100,000 US citizens (left-hand y axis and red bars). To calculate the average number of visits per US citizen in a defined age group, the total number of visits for a given age group was divided by the estimated population size for that age group.

The number of US outpatient visits with a recorded diagnosis of onychomycosis increased from 1993 to 2010 (Figure 2); however, there was no change in the ratio of onychomycosis visits to the total number of recorded visits in NAMCS database during the study period (P=.9). A combined total of 91% of onychomycosis visits were to general and family practitioners, dermatologists, or internal medicine practitioners (Figure 3). Although cardiovascular diseases and diabetes mellitus accounted for a large proportion of comorbidities, conditions affecting the feet (eg, tinea pedis, ingrown nails) also were among the most common comorbidities (Figure 4).

Figure 2. Estimated number of US outpatient visits with a recorded diagnosis of onychomycosis per year (1993-2010). Solid line represents the linear regression best fit line. Figure 3. Estimated number of US outpatient visits with a recorded diagnosis of onychomycosis by specialty (1993-2010). Figure 4. Top 10 comorbidities observed at US outpatient visits with a recorded diagnosis of onychomycosis (1993-2010).

In both topical and systemic form, terbinafine was the most commonly prescribed antifungal agent, followed by systemic fluconazole, systemic itraconazole, and topical ciclopirox (Figure 5). Over the 18-year study period, there was an increasing trend in the frequency of terbinafine prescription (regression coefficient [r]=0.01319; P=.004); a decreasing trend for fluconazole (r=-0.0053851; P=.04), itraconazole (r=-0.0113988; P<.001), griseofulvin (r=-0.0073942; P<.001), and econazole prescription (r=-0.0032405; P=.01); and no significant trend for ketoconazole (r=-0.0034553; P=.1), naftifine (r=-0.0029067; P=.06), sulconazole (r=-0.0001619; P=.8), ciclopirox (r=0.0032684; P=.1), and miconazole prescription (r=0.0002074; P=.5).

Figure 5. Leading antifungal agents prescribed at US outpatient visits with a recorded diagnosis of onychomycosis (1993-2010).

Eighty-six percent of visits were for established patients who had been seen in the related office with any diagnosis before the recorded visit and 14% of visits were for new (first-time) patients. Fluconazole was the most frequently used antifungal drug for new patients, while terbinafine was the most frequently used in other visits. Terbinafine was the most frequently prescribed antifungal drug by general and family practitioners, dermatologists, internal medicine practitioners, and all other specialties not listed.

Terbinafine was the most frequently prescribed antifungal drug in both genders and in white and black patients. Itraconazole was the most frequently prescribed antifungal drug for Hispanic patients and those of other ethnicities not listed. Terbinafine was the most frequently prescribed antifungal drug for patients with diabetes and obesity (ie, body mass index ≥30). In 19,330,000 of 19,350,000 total estimated visits included in this study, onychomycosis was the only diagnosis with a potential indication for an antifungal drug therapy, ruling out the possibility that fluconazole or other drugs were used for patients who also had candidiasis or “other specified erythematous conditions.”

Discussion

Onychomycosis is a common progressive infection of the nails that is more prevalent in older age groups, with equal prevalence in both genders and a higher prevalence in males. The NAMCS data showed higher rates of onychomycosis visits among older age groups, which is in agreement with results from prior studies.^16,17 In the current study, we observed a higher prevalence of onychomycosis visits among females as well as white and Hispanic patients. These results may be due to a higher prevalence of onychomycosis in these populations or simply a result of difference in socioeconomic level or importance of aesthetics. Although there are limited data regarding the prevalence of onychomycosis among different races and ethnicities in the United States, a high incidence of onychomycosis has been reported in Mexico.¹⁸

Repeated trauma to the great toenail from ill-fitting shoes is a predisposing factor for onychomycosis.¹⁶ In the current study, ingrown nails were among the most common comorbidities found in onychomycosis patients. Although nail dystrophy caused by onychomycosis may lead to ingrown nails, it also is possible that both conditions may be caused by trauma.

Patients with immunodeficiencies (eg, diabetes) may be predisposed to onychomycosis as well as its associated complications and morbidities (eg, cellulitis).^16,19 Diabetes affects 4% to 22% of patients with onychomycosis in different populations, including Denmark, Mexico, and India.^18,20,21 In our study, diabetes was among the most common recorded comorbidities reported during onychomycosis visits, with a prevalence of 3.4%. It is likely that many more visits involved patients with diabetes that had not been diagnosed or reported. With the increased risk for complications with diabetes, it is important for physicians to treat these patients when they have a nail infection.

The available systemic therapies for treatment of onychomycosis include griseofulvin, allylamines, and imidazoles. Comparison of griseofulvin with newer systemic antifungal agents such as terbinafine and itraconazole suggests that griseofulvin has lower efficacy and therefore is not a first-line treatment of onychomycosis.¹ Terbinafine is the most active of the currently available antidermatophyte drugs both in vitro and in vivo, with synergistic effects with imidazoles and ciclopirox.^1,22-27 A combination of topical and systemic therapies may improve cure rates of onychomycosis or possibly shorten the duration of therapy with the systemic agent.^1,2 Treatment strategies can vary according to the specialty of the treating physician, with general practitioners often preferring monotherapies and dermatologists preferring combination therapies.²⁸ In Europe, the most commonly prescribed medication for onychomycosis was topical amorolfine followed by systemic terbinafine and itraconazole.²⁸ In the current study, we could not separate data for topical versus systemic terbinafine because the NAMCS uses similar names for reporting the drug; however, the rates of prescription for allylamines and imidazoles were nearly equal (Figure 5), with terbinafine showing an increased use over time as opposed to a decreased use of imidazoles. Although fluconazole is not approved by the US Food and Drug Administration for treatment of onychomycosis, oral fluconazole was the second most common treatment prescribed in our study. Griseofulvin, which is not considered as a drug of choice in onychomycosis,¹ was prescribed in a small fraction of the visits, with a decreasing trend of usage over time.

Conclusion

Our analysis of the NAMCS data revealed that the treatment of onychomycosis in the United States is in accordance with recommendations in current guidelines. An encouraging finding was the notable downward trend in use of griseofulvin, suggesting that health care providers are changing practice to meet standard of care. Increased efforts must be made to uniformly modify practices in compliance with evidence-based recommendations and to minimize unnecessary risk and cost associated with use of drugs with lower efficacy.

Onychomycosis is a common progressive infection of the nails caused by dermatophytes, nondermatophyte molds, and yeasts, with Trichophyton rubrum being the most common causative organism.^1-3 Onychomycosis affects approximately 2% to 26% of different populations worldwide. It represents 20% to 50% of onychopathies and approximately 30% of fungal cutaneous infections.^4-9 Less than 30% of infected persons seek medical advice or treatment even in developed areas of the world.¹⁰ Onychomycosis may be a source of more widespread fungal skin infections or give rise to complications such as cellulitis. Chronic, long-lasting infection may result in nail dystrophy and can lead to pain, absence from work, and decreased quality of life.^1,11 Because the dermatophyte can contaminate communal bathing facilities and spread to others,¹² it is important to effectively target and treat patients with onychomycosis, thus reducing the rate of related morbidities.^1,9

The primary aim of onychomycosis treatment is to cure the infection and prevent relapse. Both topical and oral agents are available for the treatment of fungal nail infections. Generally, systemic therapy for onychomycosis is more successful than topical treatment, likely due to poor penetration of topical medications into the nail plate.^1,2,9 However, newer topical drugs have shown promising results in treating some types of onychomycosis.¹³ In its guidelines for treatment of onychomycosis, the British Association of Dermatologists recommends use of topical treatment under the following conditions: (1) when there is not extensive involvement of the nail plate (eg, candidal paronychia, superficial white onychomycosis, early stages of distal and lateral subungual onychomycosis), (2) when systemic therapy is contraindicated, or (3) in combination with systemic therapy.¹ Although there are multiple treatments for fungal nail infections, there are limited reports on the ways in which physicians actually use these treatments or the frequency with which they prescribe them.

This study provides a representative portrayal of onychomycosis visits in the US outpatient setting using a large nationally sampled survey. In particular, we aimed to assess the number of visits related to onychomycosis, the demographics of patients, and the treatments being prescribed for onychomycosis.

Methods

Study Design

Data from January 1, 1993, to December 31, 2010, were collected from the National Ambulatory Medical Care Survey (NAMCS), an ongoing survey of nonfederal employed US office-based physicians who are primarily engaged in direct patient care. The NAMCS has been conducted by the National Center for Health Statistics every year since 1989 to estimate the utilization of ambulatory care services in the United States. Since 1989 including 1993 to 2010, the NAMCS sampled approximately 30,000 visits per year. For each visit sampled, a 1-page patient log including demographic data, physicians’ diagnoses, services provided, and medications was completed. In the NAMCS survey, visits were divided into 2 groups: (1) visits from established patients that have been seen in that office before for any reason, and (2) visits for new (ie, first-time) patients. The current study included all visits in which fungal nail infection (code 110.1 according to the International Classification of Diseases, Ninth Revision [ICD-9]) was listed as 1 of 3 possible diagnoses.

Statistical Analysis

Sampling weights were applied to data to produce estimates for the total US outpatient setting.¹⁴ Data were analyzed using SAS version 9.2, and SAS survey analysis procedures were used to account for the clustered sampling of the survey. The total numbers of visits for which onychomycosis was 1 of 3 possible diagnoses and for which it was the sole diagnosis were reported. Visit rates per population by demographic characteristics (ie, patient sex, age, race, and ethnicity) were calculated. Population estimates were based on the 2001 NAMCS Public Micro-Data File Documentation records of the US census estimates for noninstitutionalized civilian persons.¹⁵ Trends in proportion of visits linked with an onychomycosis diagnosis over time were evaluated using the SAS SURVEYREG procedure. Types of physicians who attended to these visits as well as leading comorbidities that had been diagnosed and documented in the medical record were characterized. Onychomycosis-related medications prescribed at these visits were reported and prescribing trends over time were evaluated. Differences in the treatment prescribed according to the type of visit (ie, first-time or return visit); physician specialty; and patients’ gender, race, and health conditions (eg, obesity, diabetes mellitus) were examined. To exclude the possibility that fluconazole and other broad-spectrum antifungals were being used for secondary diagnoses, we determined the number of visits that had an additional diagnosis of either candidiasis (ICD-9 codes 112.0–112.9) or “other specified erythematous conditions” (ICD-9 code 695.89).

Results

During the 18-year study period, 636 visits with a diagnosis of onychomycosis were recorded in the NAMCS database. This unweighted number of visits corresponded with approximately 19,350,000 visits (an average of 1,075,000 visits per year) to physicians’ offices with a diagnosis of onychomycosis in the United States during this period. Among these visits, there were an estimated 4,250,000 visits with fungal nail infection as the only diagnosis (no other comorbidities recorded). The recorded visits included more female (57.6%) than male (42.4%) patients, and 85% of patients were white (Table). Patients aged 35 to 44 years accounted for the largest number of visits; however, the estimated rate of onychomycosis visits per 100,000 US citizens was highest among those aged 65 to 74 years (Figure 1).

Figure 1. Health care utilization for onychomycosis from 1993 to 2010 stratified by patient age, as defined as: (1) the total estimated number of US outpatient visits that included a diagnosis of onychomycosis (right-hand y axis and blue bars), and (2) the estimated number of visits per 100,000 US citizens (left-hand y axis and red bars). To calculate the average number of visits per US citizen in a defined age group, the total number of visits for a given age group was divided by the estimated population size for that age group.

The number of US outpatient visits with a recorded diagnosis of onychomycosis increased from 1993 to 2010 (Figure 2); however, there was no change in the ratio of onychomycosis visits to the total number of recorded visits in NAMCS database during the study period (P=.9). A combined total of 91% of onychomycosis visits were to general and family practitioners, dermatologists, or internal medicine practitioners (Figure 3). Although cardiovascular diseases and diabetes mellitus accounted for a large proportion of comorbidities, conditions affecting the feet (eg, tinea pedis, ingrown nails) also were among the most common comorbidities (Figure 4).

Figure 2. Estimated number of US outpatient visits with a recorded diagnosis of onychomycosis per year (1993-2010). Solid line represents the linear regression best fit line. Figure 3. Estimated number of US outpatient visits with a recorded diagnosis of onychomycosis by specialty (1993-2010). Figure 4. Top 10 comorbidities observed at US outpatient visits with a recorded diagnosis of onychomycosis (1993-2010).

In both topical and systemic form, terbinafine was the most commonly prescribed antifungal agent, followed by systemic fluconazole, systemic itraconazole, and topical ciclopirox (Figure 5). Over the 18-year study period, there was an increasing trend in the frequency of terbinafine prescription (regression coefficient [r]=0.01319; P=.004); a decreasing trend for fluconazole (r=-0.0053851; P=.04), itraconazole (r=-0.0113988; P<.001), griseofulvin (r=-0.0073942; P<.001), and econazole prescription (r=-0.0032405; P=.01); and no significant trend for ketoconazole (r=-0.0034553; P=.1), naftifine (r=-0.0029067; P=.06), sulconazole (r=-0.0001619; P=.8), ciclopirox (r=0.0032684; P=.1), and miconazole prescription (r=0.0002074; P=.5).

Figure 5. Leading antifungal agents prescribed at US outpatient visits with a recorded diagnosis of onychomycosis (1993-2010).

Eighty-six percent of visits were for established patients who had been seen in the related office with any diagnosis before the recorded visit and 14% of visits were for new (first-time) patients. Fluconazole was the most frequently used antifungal drug for new patients, while terbinafine was the most frequently used in other visits. Terbinafine was the most frequently prescribed antifungal drug by general and family practitioners, dermatologists, internal medicine practitioners, and all other specialties not listed.

Terbinafine was the most frequently prescribed antifungal drug in both genders and in white and black patients. Itraconazole was the most frequently prescribed antifungal drug for Hispanic patients and those of other ethnicities not listed. Terbinafine was the most frequently prescribed antifungal drug for patients with diabetes and obesity (ie, body mass index ≥30). In 19,330,000 of 19,350,000 total estimated visits included in this study, onychomycosis was the only diagnosis with a potential indication for an antifungal drug therapy, ruling out the possibility that fluconazole or other drugs were used for patients who also had candidiasis or “other specified erythematous conditions.”

Discussion

Onychomycosis is a common progressive infection of the nails that is more prevalent in older age groups, with equal prevalence in both genders and a higher prevalence in males. The NAMCS data showed higher rates of onychomycosis visits among older age groups, which is in agreement with results from prior studies.^16,17 In the current study, we observed a higher prevalence of onychomycosis visits among females as well as white and Hispanic patients. These results may be due to a higher prevalence of onychomycosis in these populations or simply a result of difference in socioeconomic level or importance of aesthetics. Although there are limited data regarding the prevalence of onychomycosis among different races and ethnicities in the United States, a high incidence of onychomycosis has been reported in Mexico.¹⁸

Repeated trauma to the great toenail from ill-fitting shoes is a predisposing factor for onychomycosis.¹⁶ In the current study, ingrown nails were among the most common comorbidities found in onychomycosis patients. Although nail dystrophy caused by onychomycosis may lead to ingrown nails, it also is possible that both conditions may be caused by trauma.

Patients with immunodeficiencies (eg, diabetes) may be predisposed to onychomycosis as well as its associated complications and morbidities (eg, cellulitis).^16,19 Diabetes affects 4% to 22% of patients with onychomycosis in different populations, including Denmark, Mexico, and India.^18,20,21 In our study, diabetes was among the most common recorded comorbidities reported during onychomycosis visits, with a prevalence of 3.4%. It is likely that many more visits involved patients with diabetes that had not been diagnosed or reported. With the increased risk for complications with diabetes, it is important for physicians to treat these patients when they have a nail infection.

The available systemic therapies for treatment of onychomycosis include griseofulvin, allylamines, and imidazoles. Comparison of griseofulvin with newer systemic antifungal agents such as terbinafine and itraconazole suggests that griseofulvin has lower efficacy and therefore is not a first-line treatment of onychomycosis.¹ Terbinafine is the most active of the currently available antidermatophyte drugs both in vitro and in vivo, with synergistic effects with imidazoles and ciclopirox.^1,22-27 A combination of topical and systemic therapies may improve cure rates of onychomycosis or possibly shorten the duration of therapy with the systemic agent.^1,2 Treatment strategies can vary according to the specialty of the treating physician, with general practitioners often preferring monotherapies and dermatologists preferring combination therapies.²⁸ In Europe, the most commonly prescribed medication for onychomycosis was topical amorolfine followed by systemic terbinafine and itraconazole.²⁸ In the current study, we could not separate data for topical versus systemic terbinafine because the NAMCS uses similar names for reporting the drug; however, the rates of prescription for allylamines and imidazoles were nearly equal (Figure 5), with terbinafine showing an increased use over time as opposed to a decreased use of imidazoles. Although fluconazole is not approved by the US Food and Drug Administration for treatment of onychomycosis, oral fluconazole was the second most common treatment prescribed in our study. Griseofulvin, which is not considered as a drug of choice in onychomycosis,¹ was prescribed in a small fraction of the visits, with a decreasing trend of usage over time.

Conclusion

Our analysis of the NAMCS data revealed that the treatment of onychomycosis in the United States is in accordance with recommendations in current guidelines. An encouraging finding was the notable downward trend in use of griseofulvin, suggesting that health care providers are changing practice to meet standard of care. Increased efforts must be made to uniformly modify practices in compliance with evidence-based recommendations and to minimize unnecessary risk and cost associated with use of drugs with lower efficacy.

Onychomycosis is a common progressive infection of the nails caused by dermatophytes, nondermatophyte molds, and yeasts, with Trichophyton rubrum being the most common causative organism.^1-3 Onychomycosis affects approximately 2% to 26% of different populations worldwide. It represents 20% to 50% of onychopathies and approximately 30% of fungal cutaneous infections.^4-9 Less than 30% of infected persons seek medical advice or treatment even in developed areas of the world.¹⁰ Onychomycosis may be a source of more widespread fungal skin infections or give rise to complications such as cellulitis. Chronic, long-lasting infection may result in nail dystrophy and can lead to pain, absence from work, and decreased quality of life.^1,11 Because the dermatophyte can contaminate communal bathing facilities and spread to others,¹² it is important to effectively target and treat patients with onychomycosis, thus reducing the rate of related morbidities.^1,9

The primary aim of onychomycosis treatment is to cure the infection and prevent relapse. Both topical and oral agents are available for the treatment of fungal nail infections. Generally, systemic therapy for onychomycosis is more successful than topical treatment, likely due to poor penetration of topical medications into the nail plate.^1,2,9 However, newer topical drugs have shown promising results in treating some types of onychomycosis.¹³ In its guidelines for treatment of onychomycosis, the British Association of Dermatologists recommends use of topical treatment under the following conditions: (1) when there is not extensive involvement of the nail plate (eg, candidal paronychia, superficial white onychomycosis, early stages of distal and lateral subungual onychomycosis), (2) when systemic therapy is contraindicated, or (3) in combination with systemic therapy.¹ Although there are multiple treatments for fungal nail infections, there are limited reports on the ways in which physicians actually use these treatments or the frequency with which they prescribe them.

This study provides a representative portrayal of onychomycosis visits in the US outpatient setting using a large nationally sampled survey. In particular, we aimed to assess the number of visits related to onychomycosis, the demographics of patients, and the treatments being prescribed for onychomycosis.

Methods

Study Design

Data from January 1, 1993, to December 31, 2010, were collected from the National Ambulatory Medical Care Survey (NAMCS), an ongoing survey of nonfederal employed US office-based physicians who are primarily engaged in direct patient care. The NAMCS has been conducted by the National Center for Health Statistics every year since 1989 to estimate the utilization of ambulatory care services in the United States. Since 1989 including 1993 to 2010, the NAMCS sampled approximately 30,000 visits per year. For each visit sampled, a 1-page patient log including demographic data, physicians’ diagnoses, services provided, and medications was completed. In the NAMCS survey, visits were divided into 2 groups: (1) visits from established patients that have been seen in that office before for any reason, and (2) visits for new (ie, first-time) patients. The current study included all visits in which fungal nail infection (code 110.1 according to the International Classification of Diseases, Ninth Revision [ICD-9]) was listed as 1 of 3 possible diagnoses.

Statistical Analysis

Sampling weights were applied to data to produce estimates for the total US outpatient setting.¹⁴ Data were analyzed using SAS version 9.2, and SAS survey analysis procedures were used to account for the clustered sampling of the survey. The total numbers of visits for which onychomycosis was 1 of 3 possible diagnoses and for which it was the sole diagnosis were reported. Visit rates per population by demographic characteristics (ie, patient sex, age, race, and ethnicity) were calculated. Population estimates were based on the 2001 NAMCS Public Micro-Data File Documentation records of the US census estimates for noninstitutionalized civilian persons.¹⁵ Trends in proportion of visits linked with an onychomycosis diagnosis over time were evaluated using the SAS SURVEYREG procedure. Types of physicians who attended to these visits as well as leading comorbidities that had been diagnosed and documented in the medical record were characterized. Onychomycosis-related medications prescribed at these visits were reported and prescribing trends over time were evaluated. Differences in the treatment prescribed according to the type of visit (ie, first-time or return visit); physician specialty; and patients’ gender, race, and health conditions (eg, obesity, diabetes mellitus) were examined. To exclude the possibility that fluconazole and other broad-spectrum antifungals were being used for secondary diagnoses, we determined the number of visits that had an additional diagnosis of either candidiasis (ICD-9 codes 112.0–112.9) or “other specified erythematous conditions” (ICD-9 code 695.89).

Results

During the 18-year study period, 636 visits with a diagnosis of onychomycosis were recorded in the NAMCS database. This unweighted number of visits corresponded with approximately 19,350,000 visits (an average of 1,075,000 visits per year) to physicians’ offices with a diagnosis of onychomycosis in the United States during this period. Among these visits, there were an estimated 4,250,000 visits with fungal nail infection as the only diagnosis (no other comorbidities recorded). The recorded visits included more female (57.6%) than male (42.4%) patients, and 85% of patients were white (Table). Patients aged 35 to 44 years accounted for the largest number of visits; however, the estimated rate of onychomycosis visits per 100,000 US citizens was highest among those aged 65 to 74 years (Figure 1).

Figure 1. Health care utilization for onychomycosis from 1993 to 2010 stratified by patient age, as defined as: (1) the total estimated number of US outpatient visits that included a diagnosis of onychomycosis (right-hand y axis and blue bars), and (2) the estimated number of visits per 100,000 US citizens (left-hand y axis and red bars). To calculate the average number of visits per US citizen in a defined age group, the total number of visits for a given age group was divided by the estimated population size for that age group.

The number of US outpatient visits with a recorded diagnosis of onychomycosis increased from 1993 to 2010 (Figure 2); however, there was no change in the ratio of onychomycosis visits to the total number of recorded visits in NAMCS database during the study period (P=.9). A combined total of 91% of onychomycosis visits were to general and family practitioners, dermatologists, or internal medicine practitioners (Figure 3). Although cardiovascular diseases and diabetes mellitus accounted for a large proportion of comorbidities, conditions affecting the feet (eg, tinea pedis, ingrown nails) also were among the most common comorbidities (Figure 4).

Figure 2. Estimated number of US outpatient visits with a recorded diagnosis of onychomycosis per year (1993-2010). Solid line represents the linear regression best fit line. Figure 3. Estimated number of US outpatient visits with a recorded diagnosis of onychomycosis by specialty (1993-2010). Figure 4. Top 10 comorbidities observed at US outpatient visits with a recorded diagnosis of onychomycosis (1993-2010).

In both topical and systemic form, terbinafine was the most commonly prescribed antifungal agent, followed by systemic fluconazole, systemic itraconazole, and topical ciclopirox (Figure 5). Over the 18-year study period, there was an increasing trend in the frequency of terbinafine prescription (regression coefficient [r]=0.01319; P=.004); a decreasing trend for fluconazole (r=-0.0053851; P=.04), itraconazole (r=-0.0113988; P<.001), griseofulvin (r=-0.0073942; P<.001), and econazole prescription (r=-0.0032405; P=.01); and no significant trend for ketoconazole (r=-0.0034553; P=.1), naftifine (r=-0.0029067; P=.06), sulconazole (r=-0.0001619; P=.8), ciclopirox (r=0.0032684; P=.1), and miconazole prescription (r=0.0002074; P=.5).

Figure 5. Leading antifungal agents prescribed at US outpatient visits with a recorded diagnosis of onychomycosis (1993-2010).

Eighty-six percent of visits were for established patients who had been seen in the related office with any diagnosis before the recorded visit and 14% of visits were for new (first-time) patients. Fluconazole was the most frequently used antifungal drug for new patients, while terbinafine was the most frequently used in other visits. Terbinafine was the most frequently prescribed antifungal drug by general and family practitioners, dermatologists, internal medicine practitioners, and all other specialties not listed.

Terbinafine was the most frequently prescribed antifungal drug in both genders and in white and black patients. Itraconazole was the most frequently prescribed antifungal drug for Hispanic patients and those of other ethnicities not listed. Terbinafine was the most frequently prescribed antifungal drug for patients with diabetes and obesity (ie, body mass index ≥30). In 19,330,000 of 19,350,000 total estimated visits included in this study, onychomycosis was the only diagnosis with a potential indication for an antifungal drug therapy, ruling out the possibility that fluconazole or other drugs were used for patients who also had candidiasis or “other specified erythematous conditions.”

Discussion

Onychomycosis is a common progressive infection of the nails that is more prevalent in older age groups, with equal prevalence in both genders and a higher prevalence in males. The NAMCS data showed higher rates of onychomycosis visits among older age groups, which is in agreement with results from prior studies.^16,17 In the current study, we observed a higher prevalence of onychomycosis visits among females as well as white and Hispanic patients. These results may be due to a higher prevalence of onychomycosis in these populations or simply a result of difference in socioeconomic level or importance of aesthetics. Although there are limited data regarding the prevalence of onychomycosis among different races and ethnicities in the United States, a high incidence of onychomycosis has been reported in Mexico.¹⁸

Repeated trauma to the great toenail from ill-fitting shoes is a predisposing factor for onychomycosis.¹⁶ In the current study, ingrown nails were among the most common comorbidities found in onychomycosis patients. Although nail dystrophy caused by onychomycosis may lead to ingrown nails, it also is possible that both conditions may be caused by trauma.

Patients with immunodeficiencies (eg, diabetes) may be predisposed to onychomycosis as well as its associated complications and morbidities (eg, cellulitis).^16,19 Diabetes affects 4% to 22% of patients with onychomycosis in different populations, including Denmark, Mexico, and India.^18,20,21 In our study, diabetes was among the most common recorded comorbidities reported during onychomycosis visits, with a prevalence of 3.4%. It is likely that many more visits involved patients with diabetes that had not been diagnosed or reported. With the increased risk for complications with diabetes, it is important for physicians to treat these patients when they have a nail infection.

The available systemic therapies for treatment of onychomycosis include griseofulvin, allylamines, and imidazoles. Comparison of griseofulvin with newer systemic antifungal agents such as terbinafine and itraconazole suggests that griseofulvin has lower efficacy and therefore is not a first-line treatment of onychomycosis.¹ Terbinafine is the most active of the currently available antidermatophyte drugs both in vitro and in vivo, with synergistic effects with imidazoles and ciclopirox.^1,22-27 A combination of topical and systemic therapies may improve cure rates of onychomycosis or possibly shorten the duration of therapy with the systemic agent.^1,2 Treatment strategies can vary according to the specialty of the treating physician, with general practitioners often preferring monotherapies and dermatologists preferring combination therapies.²⁸ In Europe, the most commonly prescribed medication for onychomycosis was topical amorolfine followed by systemic terbinafine and itraconazole.²⁸ In the current study, we could not separate data for topical versus systemic terbinafine because the NAMCS uses similar names for reporting the drug; however, the rates of prescription for allylamines and imidazoles were nearly equal (Figure 5), with terbinafine showing an increased use over time as opposed to a decreased use of imidazoles. Although fluconazole is not approved by the US Food and Drug Administration for treatment of onychomycosis, oral fluconazole was the second most common treatment prescribed in our study. Griseofulvin, which is not considered as a drug of choice in onychomycosis,¹ was prescribed in a small fraction of the visits, with a decreasing trend of usage over time.

Conclusion

Our analysis of the NAMCS data revealed that the treatment of onychomycosis in the United States is in accordance with recommendations in current guidelines. An encouraging finding was the notable downward trend in use of griseofulvin, suggesting that health care providers are changing practice to meet standard of care. Increased efforts must be made to uniformly modify practices in compliance with evidence-based recommendations and to minimize unnecessary risk and cost associated with use of drugs with lower efficacy.

MIAMI BEACH – Two new topical solutions approved in 2014 for the treatment of distal subungual onychomycosis don’t eliminate the need for oral treatment, but they do represent improvement in the options available to patients, according to Dr. Boni E. Elewski.

Oral treatments, including terbinafine, itraconazole, and fluconazole are still of value – either alone or in combination with the new solutions or other agents – for this type of onychomycosis, which is “essentially a nail bed dermatophytosis,” she said at the South Beach Symposium.

© Manuel-F-O/Thinkstock

Terbinafine has been used for 2 decades, and is probably the most commonly used treatment for onychomycosis. It is approved as a once-daily pill given for 90 days, and reportedly has a cure rate just under 40%, she said.

Itraconazole is approved as a 200-mg daily dose for 12 weeks, although most physicians use pulse dosing, prescribing 400 mg daily for a week, then for 1 week each month.

“I like this drug for my nondermatophyte patients … if you have something that you don’t think is a dermatophyte, or if they’ve failed terbinafine, this is an excellent option,” she said.

Fluconazole, her “personal favorite,” is used off label for onychomycosis, but has been shown to have good cure rates with once-weekly treatment, said Dr. Elewski of the University of Alabama at Birmingham.

“I’ll confess, I like this drug because I feel comfortable with it,” she said adding that she tells her patients to think about “Fungal Fridays” or “Toesdays” as a way to remember to take their weekly treatments.

The cure rates are quite good, she said, noting that because the nails grow so slowly, the pace of the treatment matches patient expectations. They don’t finish treatment and still have a “cruddy-looking” nail, she explained.

If any of these oral drugs are used, laboratory monitoring and periodic assessments are necessary, so treatment is a bit complicated. Adverse events remain a concern – particularly drug-drug interactions, drug eruption, cardiac issues (with itraconazole), and loss of taste (with terbinafine).

“So we do have to worry about some of these conditions, which is why having other treatments is so nice,” Dr. Elewski said.

Another reason it’s good to have more options is that no matter which drug you choose, it won’t cure everyone, she noted. Sometimes that’s because the condition is severe; patients with a dermatophyte abscess, those with very thick nails, and those with complete nail involvement associated with a nondermatophyte mold, for example, will have a poorer prognosis, regardless of which oral treatment given. Also, the condition is often complicated by concomitant disorders such as psoriasis. About 5% of patients with psoriasis have nail-only disease, and about a third of them also have onychomycosis. Others are misdiagnosed as having onychomycosis.

Alternatives that can be used alone or in combination with the oral therapies, include the two new topical solutions: efinaconazole and tavaborole, Dr. Elewski said.

Solutions are good, because you can apply them on, under, and around the nail. Both of the drugs have demonstrated effective penetration of the nail plate, allowing penetration to the nail bed where the infection exists, she noted.

The mycological cure rate with efinaconazole yields outcomes comparable to those with oral drugs.

“I think [the mycological cure] is actually the most important endpoint. Because when you want to get rid of the fungus, what do you do? You want to kill the fungus,” said Dr. Elewski, adding that mycological cure is the first sign a patient will go on to experience complete cure.

The complete cure rate is lower, but that appears to be a time-related factor. The nail takes a long time to grow, so the complete cure rate will lag behind the mycological cure rate, Dr. Elewski explained.

The other topical solution – tavaborole – is a new molecule that contains boron. Mycological cure rates in studies of the drug were in the mid-30% range, and it appears able to be used with nail polish without issues to the polish or the outcomes, she said.

In Dr. Elewski’s experience, these topicals work better than expected in clinical practice, based on the clinical trials. One patient who wasn’t eligible for the clinical trials because of a dermatophytosis, for example, was nearly clear within 5 months, and is now totally cured, she said.

“So these treatments are effective as monotherapy, but could be used as an adjunct with systemic therapy, and perhaps also in nondermatophyte cases of onychomycosis,” Dr. Elewski noted. “I think it would be a better option to pick one of these topical drugs than putting someone on a prolonged course of itraconazole if at all possible.” The safety issue would be more favorable with the topical antifungal solution, she said.

A treatment that should never be used is ketoconazole, she noted, explaining that although the drug was never approved specifically for onychomycosis, it was often prescribed for the treatment of tinea versicolor. Because of safety concerns, the FDA removed its indication for all cutaneous fungal infections in 2013.

Dr. Elewski is a consultant for Valeant Pharmaceuticals and a contracted researcher for Anacor Pharmaceuticals.

[email protected]

MIAMI BEACH – Two new topical solutions approved in 2014 for the treatment of distal subungual onychomycosis don’t eliminate the need for oral treatment, but they do represent improvement in the options available to patients, according to Dr. Boni E. Elewski.

Oral treatments, including terbinafine, itraconazole, and fluconazole are still of value – either alone or in combination with the new solutions or other agents – for this type of onychomycosis, which is “essentially a nail bed dermatophytosis,” she said at the South Beach Symposium.

© Manuel-F-O/Thinkstock

Terbinafine has been used for 2 decades, and is probably the most commonly used treatment for onychomycosis. It is approved as a once-daily pill given for 90 days, and reportedly has a cure rate just under 40%, she said.

Itraconazole is approved as a 200-mg daily dose for 12 weeks, although most physicians use pulse dosing, prescribing 400 mg daily for a week, then for 1 week each month.

“I like this drug for my nondermatophyte patients … if you have something that you don’t think is a dermatophyte, or if they’ve failed terbinafine, this is an excellent option,” she said.

Fluconazole, her “personal favorite,” is used off label for onychomycosis, but has been shown to have good cure rates with once-weekly treatment, said Dr. Elewski of the University of Alabama at Birmingham.

“I’ll confess, I like this drug because I feel comfortable with it,” she said adding that she tells her patients to think about “Fungal Fridays” or “Toesdays” as a way to remember to take their weekly treatments.

The cure rates are quite good, she said, noting that because the nails grow so slowly, the pace of the treatment matches patient expectations. They don’t finish treatment and still have a “cruddy-looking” nail, she explained.

If any of these oral drugs are used, laboratory monitoring and periodic assessments are necessary, so treatment is a bit complicated. Adverse events remain a concern – particularly drug-drug interactions, drug eruption, cardiac issues (with itraconazole), and loss of taste (with terbinafine).

“So we do have to worry about some of these conditions, which is why having other treatments is so nice,” Dr. Elewski said.

Another reason it’s good to have more options is that no matter which drug you choose, it won’t cure everyone, she noted. Sometimes that’s because the condition is severe; patients with a dermatophyte abscess, those with very thick nails, and those with complete nail involvement associated with a nondermatophyte mold, for example, will have a poorer prognosis, regardless of which oral treatment given. Also, the condition is often complicated by concomitant disorders such as psoriasis. About 5% of patients with psoriasis have nail-only disease, and about a third of them also have onychomycosis. Others are misdiagnosed as having onychomycosis.

Alternatives that can be used alone or in combination with the oral therapies, include the two new topical solutions: efinaconazole and tavaborole, Dr. Elewski said.

Solutions are good, because you can apply them on, under, and around the nail. Both of the drugs have demonstrated effective penetration of the nail plate, allowing penetration to the nail bed where the infection exists, she noted.

The mycological cure rate with efinaconazole yields outcomes comparable to those with oral drugs.

“I think [the mycological cure] is actually the most important endpoint. Because when you want to get rid of the fungus, what do you do? You want to kill the fungus,” said Dr. Elewski, adding that mycological cure is the first sign a patient will go on to experience complete cure.

The complete cure rate is lower, but that appears to be a time-related factor. The nail takes a long time to grow, so the complete cure rate will lag behind the mycological cure rate, Dr. Elewski explained.

The other topical solution – tavaborole – is a new molecule that contains boron. Mycological cure rates in studies of the drug were in the mid-30% range, and it appears able to be used with nail polish without issues to the polish or the outcomes, she said.

In Dr. Elewski’s experience, these topicals work better than expected in clinical practice, based on the clinical trials. One patient who wasn’t eligible for the clinical trials because of a dermatophytosis, for example, was nearly clear within 5 months, and is now totally cured, she said.

“So these treatments are effective as monotherapy, but could be used as an adjunct with systemic therapy, and perhaps also in nondermatophyte cases of onychomycosis,” Dr. Elewski noted. “I think it would be a better option to pick one of these topical drugs than putting someone on a prolonged course of itraconazole if at all possible.” The safety issue would be more favorable with the topical antifungal solution, she said.

A treatment that should never be used is ketoconazole, she noted, explaining that although the drug was never approved specifically for onychomycosis, it was often prescribed for the treatment of tinea versicolor. Because of safety concerns, the FDA removed its indication for all cutaneous fungal infections in 2013.

Dr. Elewski is a consultant for Valeant Pharmaceuticals and a contracted researcher for Anacor Pharmaceuticals.

[email protected]

MIAMI BEACH – Two new topical solutions approved in 2014 for the treatment of distal subungual onychomycosis don’t eliminate the need for oral treatment, but they do represent improvement in the options available to patients, according to Dr. Boni E. Elewski.

Oral treatments, including terbinafine, itraconazole, and fluconazole are still of value – either alone or in combination with the new solutions or other agents – for this type of onychomycosis, which is “essentially a nail bed dermatophytosis,” she said at the South Beach Symposium.

© Manuel-F-O/Thinkstock

Terbinafine has been used for 2 decades, and is probably the most commonly used treatment for onychomycosis. It is approved as a once-daily pill given for 90 days, and reportedly has a cure rate just under 40%, she said.

Itraconazole is approved as a 200-mg daily dose for 12 weeks, although most physicians use pulse dosing, prescribing 400 mg daily for a week, then for 1 week each month.

“I like this drug for my nondermatophyte patients … if you have something that you don’t think is a dermatophyte, or if they’ve failed terbinafine, this is an excellent option,” she said.

Fluconazole, her “personal favorite,” is used off label for onychomycosis, but has been shown to have good cure rates with once-weekly treatment, said Dr. Elewski of the University of Alabama at Birmingham.

“I’ll confess, I like this drug because I feel comfortable with it,” she said adding that she tells her patients to think about “Fungal Fridays” or “Toesdays” as a way to remember to take their weekly treatments.

The cure rates are quite good, she said, noting that because the nails grow so slowly, the pace of the treatment matches patient expectations. They don’t finish treatment and still have a “cruddy-looking” nail, she explained.

If any of these oral drugs are used, laboratory monitoring and periodic assessments are necessary, so treatment is a bit complicated. Adverse events remain a concern – particularly drug-drug interactions, drug eruption, cardiac issues (with itraconazole), and loss of taste (with terbinafine).

“So we do have to worry about some of these conditions, which is why having other treatments is so nice,” Dr. Elewski said.

Another reason it’s good to have more options is that no matter which drug you choose, it won’t cure everyone, she noted. Sometimes that’s because the condition is severe; patients with a dermatophyte abscess, those with very thick nails, and those with complete nail involvement associated with a nondermatophyte mold, for example, will have a poorer prognosis, regardless of which oral treatment given. Also, the condition is often complicated by concomitant disorders such as psoriasis. About 5% of patients with psoriasis have nail-only disease, and about a third of them also have onychomycosis. Others are misdiagnosed as having onychomycosis.

Alternatives that can be used alone or in combination with the oral therapies, include the two new topical solutions: efinaconazole and tavaborole, Dr. Elewski said.

Solutions are good, because you can apply them on, under, and around the nail. Both of the drugs have demonstrated effective penetration of the nail plate, allowing penetration to the nail bed where the infection exists, she noted.

The mycological cure rate with efinaconazole yields outcomes comparable to those with oral drugs.

“I think [the mycological cure] is actually the most important endpoint. Because when you want to get rid of the fungus, what do you do? You want to kill the fungus,” said Dr. Elewski, adding that mycological cure is the first sign a patient will go on to experience complete cure.

The complete cure rate is lower, but that appears to be a time-related factor. The nail takes a long time to grow, so the complete cure rate will lag behind the mycological cure rate, Dr. Elewski explained.

The other topical solution – tavaborole – is a new molecule that contains boron. Mycological cure rates in studies of the drug were in the mid-30% range, and it appears able to be used with nail polish without issues to the polish or the outcomes, she said.

In Dr. Elewski’s experience, these topicals work better than expected in clinical practice, based on the clinical trials. One patient who wasn’t eligible for the clinical trials because of a dermatophytosis, for example, was nearly clear within 5 months, and is now totally cured, she said.

“So these treatments are effective as monotherapy, but could be used as an adjunct with systemic therapy, and perhaps also in nondermatophyte cases of onychomycosis,” Dr. Elewski noted. “I think it would be a better option to pick one of these topical drugs than putting someone on a prolonged course of itraconazole if at all possible.” The safety issue would be more favorable with the topical antifungal solution, she said.

A treatment that should never be used is ketoconazole, she noted, explaining that although the drug was never approved specifically for onychomycosis, it was often prescribed for the treatment of tinea versicolor. Because of safety concerns, the FDA removed its indication for all cutaneous fungal infections in 2013.

Dr. Elewski is a consultant for Valeant Pharmaceuticals and a contracted researcher for Anacor Pharmaceuticals.

[email protected]

To the Editor:

Onychomycosis is a common nail disease that frequently is caused by dermatophytes and is diagnosed by direct microscopy. Conventional diagnostic methods are often time consuming and can produce false-positive or false-negative results. We report a case of onychomycosis diagnosed by confocal microscopy and confirmed with routine potassium hydroxide (KOH) examination and fungal culture. Confocal microscopy is a reliable, practical, and noninvasive technique in the diagnosis of onychomycosis.

A 46-year-old woman presented with yellow-brown discoloration and dystrophy of the toenails (Figure 1) that had become worse over a 5-year period. She was otherwise healthy and had no other dermatologic problems. Examination revealed yellow-brown discoloration, subungual hyperkeratosis, and onycholysis of the toenails. Clinically, a diagnosis of onychomycosis was made. Potassium hydroxide examination of a scraping from the subungual region showed fungal elements. Trichophyton rubrum on Sabouraud dextrose agar was determined.

Figure 1. Onycholysis and onychodystrophy affecting the toes. Figure 2. In vivo confocal image of hyphae (arrows).

We performed both in vivo and in vitro confocal laser scanning microscopic examination of the nail of the right great toe (Figure 2). For the diagnosis of onychomycosis in our case, we used a multilaser reflectance confocal microscope (RCM) with a wavelength of 786 nm. In vivo confocal microscopy of the nail revealed branching hyphae just below the surface of the nail plate. Hyphae were seen as refractile, bright, linear structures along the laminates of the nail.

Onychomycosis is a common condition affecting 5.5% of the population worldwide and representing 20% to 40% of all onychopathies and approximately 30% of cutaneous mycotic infections.^1,2 There are many methods available to confirm the clinical diagnosis of onychomycosis by detecting the causative organisms. Direct microscopic examination of the scraping with a KOH culture, histopathologic assessment with periodic acid–Schiff staining, immunofluorescence analysis with calcofluor white staining, enzyme analysis, and polymerase chain reaction can be used for diagnosis of fungal infections. The most frequently used diagnostic method for onychomycosis is KOH examination of the scraping; however, fungal culture and histopathologic examination also can be used in cases having diagnostic difficulties.^1,3,4 There are many studies comparing the efficacies of these methods in the literature.^5-9

The causative fungal agent should be determined with at least 1 laboratory method due to the high cost, long duration, and serious potential adverse effects of systemic antifungal treatment. Direct microscopic examination with KOH in the diagnosis of onychomycosis is simple, fast, and inexpensive. However, inadequate material, using crystallized KOH for hydrolysis, insufficient or too much hydrolysis of scrapings, inappropriate staining, and not scanning all areas in the microscopy produce false-negative results. Similarly, secondary contamination of hair, cotton, yarn, or air bubbles mimicking fungal structures can cause false-positive results.^9,10

Fungal culture is another diagnostic method that is accepted as the gold standard for diagnosis of onychomycosis.⁹ However, fungal cultures were positive in only 43% to 50% of all cases of onychomycosis that were diagnosed with other methods,^11,12 which may be due to the loss of viability and ability of the fungi to grow in culture media during the transport. A major advantage of fungal culture is that the fungal agent can be classified as dermatophyte, nondermatophyte, mold, or yeast. However, culture does determine if the growing fungi is contamination or the real pathogen. Moreover, it is necessary to wait 3 to 4 weeks for culture results. For nondermatophyte fungi this time may be much longer.¹²

In vivo RCM is a noninvasive imaging method that allows optical en face sectioning of the living tissue with high resolution. Currently, RCM has a wide range of applications, such as the evaluation of both benign and malignant skin lesions in clinical dermatology.¹³

In vivo RCM was used first by Hongcharu et al.¹⁴ The diagnoses of onychomycosis and fungal hyphae were shown both in vivo and in vitro.¹⁴ The sensitivity and specificity of confocal examination in the diagnosis of onychomycosis is not known yet. Large clinical trials are needed to assess the sensitivity and specificity of this method in diagnosing fungal infections.

Onychomycosis is a contagious infectious disease characterized by hyphae proliferation in the nail plate. Definitive diagnosis is necessary before treatment because onychomycosis can be mistaken for many infectious or noninfectious skin diseases with nail involvement. Conventional methods are time consuming, laborious, and less reliable. Instead of high-cost procedures, in vivo confocal microscopic examination can be a rapid and reliable diagnostic method for onychomycosis in the near future.

To the Editor:

Onychomycosis is a common nail disease that frequently is caused by dermatophytes and is diagnosed by direct microscopy. Conventional diagnostic methods are often time consuming and can produce false-positive or false-negative results. We report a case of onychomycosis diagnosed by confocal microscopy and confirmed with routine potassium hydroxide (KOH) examination and fungal culture. Confocal microscopy is a reliable, practical, and noninvasive technique in the diagnosis of onychomycosis.

A 46-year-old woman presented with yellow-brown discoloration and dystrophy of the toenails (Figure 1) that had become worse over a 5-year period. She was otherwise healthy and had no other dermatologic problems. Examination revealed yellow-brown discoloration, subungual hyperkeratosis, and onycholysis of the toenails. Clinically, a diagnosis of onychomycosis was made. Potassium hydroxide examination of a scraping from the subungual region showed fungal elements. Trichophyton rubrum on Sabouraud dextrose agar was determined.

Figure 1. Onycholysis and onychodystrophy affecting the toes. Figure 2. In vivo confocal image of hyphae (arrows).

We performed both in vivo and in vitro confocal laser scanning microscopic examination of the nail of the right great toe (Figure 2). For the diagnosis of onychomycosis in our case, we used a multilaser reflectance confocal microscope (RCM) with a wavelength of 786 nm. In vivo confocal microscopy of the nail revealed branching hyphae just below the surface of the nail plate. Hyphae were seen as refractile, bright, linear structures along the laminates of the nail.

Onychomycosis is a common condition affecting 5.5% of the population worldwide and representing 20% to 40% of all onychopathies and approximately 30% of cutaneous mycotic infections.^1,2 There are many methods available to confirm the clinical diagnosis of onychomycosis by detecting the causative organisms. Direct microscopic examination of the scraping with a KOH culture, histopathologic assessment with periodic acid–Schiff staining, immunofluorescence analysis with calcofluor white staining, enzyme analysis, and polymerase chain reaction can be used for diagnosis of fungal infections. The most frequently used diagnostic method for onychomycosis is KOH examination of the scraping; however, fungal culture and histopathologic examination also can be used in cases having diagnostic difficulties.^1,3,4 There are many studies comparing the efficacies of these methods in the literature.^5-9

The causative fungal agent should be determined with at least 1 laboratory method due to the high cost, long duration, and serious potential adverse effects of systemic antifungal treatment. Direct microscopic examination with KOH in the diagnosis of onychomycosis is simple, fast, and inexpensive. However, inadequate material, using crystallized KOH for hydrolysis, insufficient or too much hydrolysis of scrapings, inappropriate staining, and not scanning all areas in the microscopy produce false-negative results. Similarly, secondary contamination of hair, cotton, yarn, or air bubbles mimicking fungal structures can cause false-positive results.^9,10

Fungal culture is another diagnostic method that is accepted as the gold standard for diagnosis of onychomycosis.⁹ However, fungal cultures were positive in only 43% to 50% of all cases of onychomycosis that were diagnosed with other methods,^11,12 which may be due to the loss of viability and ability of the fungi to grow in culture media during the transport. A major advantage of fungal culture is that the fungal agent can be classified as dermatophyte, nondermatophyte, mold, or yeast. However, culture does determine if the growing fungi is contamination or the real pathogen. Moreover, it is necessary to wait 3 to 4 weeks for culture results. For nondermatophyte fungi this time may be much longer.¹²

In vivo RCM is a noninvasive imaging method that allows optical en face sectioning of the living tissue with high resolution. Currently, RCM has a wide range of applications, such as the evaluation of both benign and malignant skin lesions in clinical dermatology.¹³

In vivo RCM was used first by Hongcharu et al.¹⁴ The diagnoses of onychomycosis and fungal hyphae were shown both in vivo and in vitro.¹⁴ The sensitivity and specificity of confocal examination in the diagnosis of onychomycosis is not known yet. Large clinical trials are needed to assess the sensitivity and specificity of this method in diagnosing fungal infections.

Onychomycosis is a contagious infectious disease characterized by hyphae proliferation in the nail plate. Definitive diagnosis is necessary before treatment because onychomycosis can be mistaken for many infectious or noninfectious skin diseases with nail involvement. Conventional methods are time consuming, laborious, and less reliable. Instead of high-cost procedures, in vivo confocal microscopic examination can be a rapid and reliable diagnostic method for onychomycosis in the near future.

To the Editor:

Onychomycosis is a common nail disease that frequently is caused by dermatophytes and is diagnosed by direct microscopy. Conventional diagnostic methods are often time consuming and can produce false-positive or false-negative results. We report a case of onychomycosis diagnosed by confocal microscopy and confirmed with routine potassium hydroxide (KOH) examination and fungal culture. Confocal microscopy is a reliable, practical, and noninvasive technique in the diagnosis of onychomycosis.

A 46-year-old woman presented with yellow-brown discoloration and dystrophy of the toenails (Figure 1) that had become worse over a 5-year period. She was otherwise healthy and had no other dermatologic problems. Examination revealed yellow-brown discoloration, subungual hyperkeratosis, and onycholysis of the toenails. Clinically, a diagnosis of onychomycosis was made. Potassium hydroxide examination of a scraping from the subungual region showed fungal elements. Trichophyton rubrum on Sabouraud dextrose agar was determined.

Figure 1. Onycholysis and onychodystrophy affecting the toes. Figure 2. In vivo confocal image of hyphae (arrows).

We performed both in vivo and in vitro confocal laser scanning microscopic examination of the nail of the right great toe (Figure 2). For the diagnosis of onychomycosis in our case, we used a multilaser reflectance confocal microscope (RCM) with a wavelength of 786 nm. In vivo confocal microscopy of the nail revealed branching hyphae just below the surface of the nail plate. Hyphae were seen as refractile, bright, linear structures along the laminates of the nail.

Onychomycosis is a common condition affecting 5.5% of the population worldwide and representing 20% to 40% of all onychopathies and approximately 30% of cutaneous mycotic infections.^1,2 There are many methods available to confirm the clinical diagnosis of onychomycosis by detecting the causative organisms. Direct microscopic examination of the scraping with a KOH culture, histopathologic assessment with periodic acid–Schiff staining, immunofluorescence analysis with calcofluor white staining, enzyme analysis, and polymerase chain reaction can be used for diagnosis of fungal infections. The most frequently used diagnostic method for onychomycosis is KOH examination of the scraping; however, fungal culture and histopathologic examination also can be used in cases having diagnostic difficulties.^1,3,4 There are many studies comparing the efficacies of these methods in the literature.^5-9

The causative fungal agent should be determined with at least 1 laboratory method due to the high cost, long duration, and serious potential adverse effects of systemic antifungal treatment. Direct microscopic examination with KOH in the diagnosis of onychomycosis is simple, fast, and inexpensive. However, inadequate material, using crystallized KOH for hydrolysis, insufficient or too much hydrolysis of scrapings, inappropriate staining, and not scanning all areas in the microscopy produce false-negative results. Similarly, secondary contamination of hair, cotton, yarn, or air bubbles mimicking fungal structures can cause false-positive results.^9,10

Fungal culture is another diagnostic method that is accepted as the gold standard for diagnosis of onychomycosis.⁹ However, fungal cultures were positive in only 43% to 50% of all cases of onychomycosis that were diagnosed with other methods,^11,12 which may be due to the loss of viability and ability of the fungi to grow in culture media during the transport. A major advantage of fungal culture is that the fungal agent can be classified as dermatophyte, nondermatophyte, mold, or yeast. However, culture does determine if the growing fungi is contamination or the real pathogen. Moreover, it is necessary to wait 3 to 4 weeks for culture results. For nondermatophyte fungi this time may be much longer.¹²

In vivo RCM is a noninvasive imaging method that allows optical en face sectioning of the living tissue with high resolution. Currently, RCM has a wide range of applications, such as the evaluation of both benign and malignant skin lesions in clinical dermatology.¹³

In vivo RCM was used first by Hongcharu et al.¹⁴ The diagnoses of onychomycosis and fungal hyphae were shown both in vivo and in vitro.¹⁴ The sensitivity and specificity of confocal examination in the diagnosis of onychomycosis is not known yet. Large clinical trials are needed to assess the sensitivity and specificity of this method in diagnosing fungal infections.

Onychomycosis is a contagious infectious disease characterized by hyphae proliferation in the nail plate. Definitive diagnosis is necessary before treatment because onychomycosis can be mistaken for many infectious or noninfectious skin diseases with nail involvement. Conventional methods are time consuming, laborious, and less reliable. Instead of high-cost procedures, in vivo confocal microscopic examination can be a rapid and reliable diagnostic method for onychomycosis in the near future.

Nail matrix biopsies are performed to confirm a diagnosis or surgically remove a skin lesion that is affecting the growth of the nail plate. The procedure may be used to identify:

Nail biopsy can lead to complications such as bleeding, infection, or scarring. Postoperative scarring can cause permanent nail splitting, dystrophy, or both.

In a Cosmetic Dermatology article, “Matrix Biopsy of Longitudinal Melanonychia and Longitudinal Erythronychia: A Step-by-Step Approach,” Drs. Siobhan C. Collins and Nathaniel J. Jellinek review 6 techniques used to biopsy the nail matrix.

Techniques used to biopsy the nail matrix. From Cosmet Dermatol. 2009;22:130-136.

In the setting of longitudinal melanonychia (to diagnose nail melanoma or SCC) and longitudinal erythronychia (to diagnose SCC and rarely amelanotic melanoma or basal cell carcinoma), the techniques they describe accomplish 3 fundamental goals of nail surgery:

Dermatologists must be confident when performing nail biopsies and the techniques discussed by the authors will help approach nail surgery with more certainty.

At the 73rd Annual Meeting of the American Academy of Dermatology, Dr. Jellinek provides a hands-on approach to nail surgery. On Saturday, March 21, he will provide tips for nail surgeries at the “Medical and Surgical Management of Nail Disorders” lecture.

For more information, read the Collins and Jellinek article from Cosmetic Dermatology.

Nail matrix biopsies are performed to confirm a diagnosis or surgically remove a skin lesion that is affecting the growth of the nail plate. The procedure may be used to identify:

Nail biopsy can lead to complications such as bleeding, infection, or scarring. Postoperative scarring can cause permanent nail splitting, dystrophy, or both.

In a Cosmetic Dermatology article, “Matrix Biopsy of Longitudinal Melanonychia and Longitudinal Erythronychia: A Step-by-Step Approach,” Drs. Siobhan C. Collins and Nathaniel J. Jellinek review 6 techniques used to biopsy the nail matrix.

Techniques used to biopsy the nail matrix. From Cosmet Dermatol. 2009;22:130-136.

In the setting of longitudinal melanonychia (to diagnose nail melanoma or SCC) and longitudinal erythronychia (to diagnose SCC and rarely amelanotic melanoma or basal cell carcinoma), the techniques they describe accomplish 3 fundamental goals of nail surgery:

Dermatologists must be confident when performing nail biopsies and the techniques discussed by the authors will help approach nail surgery with more certainty.

At the 73rd Annual Meeting of the American Academy of Dermatology, Dr. Jellinek provides a hands-on approach to nail surgery. On Saturday, March 21, he will provide tips for nail surgeries at the “Medical and Surgical Management of Nail Disorders” lecture.

For more information, read the Collins and Jellinek article from Cosmetic Dermatology.

Nail matrix biopsies are performed to confirm a diagnosis or surgically remove a skin lesion that is affecting the growth of the nail plate. The procedure may be used to identify:

Nail biopsy can lead to complications such as bleeding, infection, or scarring. Postoperative scarring can cause permanent nail splitting, dystrophy, or both.

In a Cosmetic Dermatology article, “Matrix Biopsy of Longitudinal Melanonychia and Longitudinal Erythronychia: A Step-by-Step Approach,” Drs. Siobhan C. Collins and Nathaniel J. Jellinek review 6 techniques used to biopsy the nail matrix.

Techniques used to biopsy the nail matrix. From Cosmet Dermatol. 2009;22:130-136.

In the setting of longitudinal melanonychia (to diagnose nail melanoma or SCC) and longitudinal erythronychia (to diagnose SCC and rarely amelanotic melanoma or basal cell carcinoma), the techniques they describe accomplish 3 fundamental goals of nail surgery:

Dermatologists must be confident when performing nail biopsies and the techniques discussed by the authors will help approach nail surgery with more certainty.

At the 73rd Annual Meeting of the American Academy of Dermatology, Dr. Jellinek provides a hands-on approach to nail surgery. On Saturday, March 21, he will provide tips for nail surgeries at the “Medical and Surgical Management of Nail Disorders” lecture.

For more information, read the Collins and Jellinek article from Cosmetic Dermatology.

To the Editor:

First identified by Samuel Wilks in 1852, trichorrhexis nodosa (TN) is a congenital or acquired hair shaft disorder that is characterized by fragile and easily broken hair.¹ Congenital TN is rare and can occur in syndromes such as pseudomonilethrix, Netherton syndrome, pili annulati,² argininosuccinic aciduria,³ trichothiodystrophy,⁴ Menkes syndrome,⁵ and trichohepatoenteric syndrome.⁶ The primary congenital form of TN is inherited as an autosomal-dominant trait in some families. Acquired TN is the most common hair shaft abnormality and often is overlooked. It is provoked by hair injury, usually mechanical or physical, or chemical trauma.^7,8

Chemical trauma is caused by the use of permanent hair liquids or dyes. Mechanical injuries are the result of frequent brushing, scalp massage, or lengthy backcombing, and physical damage includes excessive UV exposure or repeated application of heat. Habit tics, trichotillomania, and the scratching and pulling associated with pruritic dermatoses also can result in sufficient damage to provoke TN. Furthermore, this acquired disorder may develop from malnutrition, particularly iron deficiency, or endocrinopathy such as hypothyroidism.⁹ Seasonal recurrence of TN has been reported from the cumulative effect of repeated soaking in salt water and exposure to UV light. Macroscopically, hair shafts affected by TN contain small white nodes at irregular intervals throughout the length of the hair shaft. These nodes represent areas of cuticular cell disruption, which allows the underlying cortical fibers to separate and fray and gives the node the microscopic appearance of 2 brooms or paintbrushes thrusting together end-to-end by the bristles. The classic description is known as paintbrush fracture.¹⁰ Generally, complete breakage occurs at these nodes.

A 21-year-old white woman presented to our clinic with hair fragility and inability to grow long hair of 2 years’ duration. The hair was lusterless and dry. Dermoscopic examination revealed broken blunt-ended hair of uneven length with minute pinpoint grayish white nodules (Figure 1). Small fragments could be easily broken off with gentle tugging on the distal ends. She reported a history of severe sunlight and seawater exposure during the last 2 summers and the continuous use of a flat iron in the last year. Microscopic examination of hair samples with a scanning electron microscope showed the characteristic paintbrush fracture (Figure 2). She had no history of diseases, and blood examinations including complete blood cell count, thyroid function test, and iron levels were within reference range.

Figure 1. Dermoscopy revealed broken blunt-ended hair of uneven length with minute pinpoint grayish white nodules (original magnification ×30). Figure 2. Scanning electron microscopy showed characteristic paintbrush fracture of the hair shaft (original magnification ×748).

We hypothesize that the seasonal damage caused by exposure to UV light and salt water with repeated trauma from the heat of the flat iron caused distal TN. The patient was given an explanation about the diagnosis of TN and was instructed to avoid the practices that were suspected causes of the condition. Use of a gentle shampoo and conditioner also was recommended. At 6-month follow-up, we noticed an improvement of the quality of hair with a reduction in the whitish nodules and a revival of hair growth.

Acquired TN has been classified into 3 clinical forms: proximal, distal, and localized.¹ Proximal TN is common in black individuals who use caustic chemicals when styling the hair. The involved hairs develop the characteristic nodes that break within a few centimeters from the scalp, especially in areas subject to friction from combing or sleeping. Distal TN primarily occurs in white or Asian individuals. In this disorder, nodes and breakage occur near the ends of the hairs that appear dull, dry, and uneven. Breakage commonly is associated with trichoptilosis, or longitudinal splitting, commonly referred to as split ends. This breakage may reflect frequent use of shampoo or heat treatments. The distal acquired form may simulate dandruff or pediculosis and the detection of this hair defect often is casual.

Localized TN, described by Raymond Sabouraud in 1921, is a rare disorder. It occurs in a patch that is usually a few centimeters long. It generally is accompanied by a pruritic dermatosis, such as circumscribed neurodermatitis, contact dermatitis, or atopic dermatitis. Scratching and rubbing most likely are the ultimate causes.

Trichorrhexis nodosa can spontaneously resolve. In all cases, diagnosis depends on careful microscopy examination and, if possible, scanning electron microscopy. Treatment is aimed at minimizing mechanical and physical injury, and chemical trauma. Excessive brushing, hot-combing, permanent waving, and other harsh hair treatments should be avoided. If the hair is long and the damage is distal, it may be sufficient to cut the distal fraction and to change cosmetic practices to prevent relapse.

Dermatologists who see patients with hair fragility and inability to grow long hair should consider the diagnosis of TN. Acquired TN often is reversible. Complete resolution may take 2 to 4 years depending on the growth of new anagen hairs. All patients with a history of white flecking on the scalp, abnormal fragility of the hair, and failure to attain normal hair length should be questioned about their routine hair care habits as well as environmental or chemical exposures to determine and remove the source of physical or chemical trauma.

To the Editor:

First identified by Samuel Wilks in 1852, trichorrhexis nodosa (TN) is a congenital or acquired hair shaft disorder that is characterized by fragile and easily broken hair.¹ Congenital TN is rare and can occur in syndromes such as pseudomonilethrix, Netherton syndrome, pili annulati,² argininosuccinic aciduria,³ trichothiodystrophy,⁴ Menkes syndrome,⁵ and trichohepatoenteric syndrome.⁶ The primary congenital form of TN is inherited as an autosomal-dominant trait in some families. Acquired TN is the most common hair shaft abnormality and often is overlooked. It is provoked by hair injury, usually mechanical or physical, or chemical trauma.^7,8

Chemical trauma is caused by the use of permanent hair liquids or dyes. Mechanical injuries are the result of frequent brushing, scalp massage, or lengthy backcombing, and physical damage includes excessive UV exposure or repeated application of heat. Habit tics, trichotillomania, and the scratching and pulling associated with pruritic dermatoses also can result in sufficient damage to provoke TN. Furthermore, this acquired disorder may develop from malnutrition, particularly iron deficiency, or endocrinopathy such as hypothyroidism.⁹ Seasonal recurrence of TN has been reported from the cumulative effect of repeated soaking in salt water and exposure to UV light. Macroscopically, hair shafts affected by TN contain small white nodes at irregular intervals throughout the length of the hair shaft. These nodes represent areas of cuticular cell disruption, which allows the underlying cortical fibers to separate and fray and gives the node the microscopic appearance of 2 brooms or paintbrushes thrusting together end-to-end by the bristles. The classic description is known as paintbrush fracture.¹⁰ Generally, complete breakage occurs at these nodes.

A 21-year-old white woman presented to our clinic with hair fragility and inability to grow long hair of 2 years’ duration. The hair was lusterless and dry. Dermoscopic examination revealed broken blunt-ended hair of uneven length with minute pinpoint grayish white nodules (Figure 1). Small fragments could be easily broken off with gentle tugging on the distal ends. She reported a history of severe sunlight and seawater exposure during the last 2 summers and the continuous use of a flat iron in the last year. Microscopic examination of hair samples with a scanning electron microscope showed the characteristic paintbrush fracture (Figure 2). She had no history of diseases, and blood examinations including complete blood cell count, thyroid function test, and iron levels were within reference range.

Figure 1. Dermoscopy revealed broken blunt-ended hair of uneven length with minute pinpoint grayish white nodules (original magnification ×30). Figure 2. Scanning electron microscopy showed characteristic paintbrush fracture of the hair shaft (original magnification ×748).

We hypothesize that the seasonal damage caused by exposure to UV light and salt water with repeated trauma from the heat of the flat iron caused distal TN. The patient was given an explanation about the diagnosis of TN and was instructed to avoid the practices that were suspected causes of the condition. Use of a gentle shampoo and conditioner also was recommended. At 6-month follow-up, we noticed an improvement of the quality of hair with a reduction in the whitish nodules and a revival of hair growth.

Acquired TN has been classified into 3 clinical forms: proximal, distal, and localized.¹ Proximal TN is common in black individuals who use caustic chemicals when styling the hair. The involved hairs develop the characteristic nodes that break within a few centimeters from the scalp, especially in areas subject to friction from combing or sleeping. Distal TN primarily occurs in white or Asian individuals. In this disorder, nodes and breakage occur near the ends of the hairs that appear dull, dry, and uneven. Breakage commonly is associated with trichoptilosis, or longitudinal splitting, commonly referred to as split ends. This breakage may reflect frequent use of shampoo or heat treatments. The distal acquired form may simulate dandruff or pediculosis and the detection of this hair defect often is casual.

Localized TN, described by Raymond Sabouraud in 1921, is a rare disorder. It occurs in a patch that is usually a few centimeters long. It generally is accompanied by a pruritic dermatosis, such as circumscribed neurodermatitis, contact dermatitis, or atopic dermatitis. Scratching and rubbing most likely are the ultimate causes.

Trichorrhexis nodosa can spontaneously resolve. In all cases, diagnosis depends on careful microscopy examination and, if possible, scanning electron microscopy. Treatment is aimed at minimizing mechanical and physical injury, and chemical trauma. Excessive brushing, hot-combing, permanent waving, and other harsh hair treatments should be avoided. If the hair is long and the damage is distal, it may be sufficient to cut the distal fraction and to change cosmetic practices to prevent relapse.

Dermatologists who see patients with hair fragility and inability to grow long hair should consider the diagnosis of TN. Acquired TN often is reversible. Complete resolution may take 2 to 4 years depending on the growth of new anagen hairs. All patients with a history of white flecking on the scalp, abnormal fragility of the hair, and failure to attain normal hair length should be questioned about their routine hair care habits as well as environmental or chemical exposures to determine and remove the source of physical or chemical trauma.

To the Editor:

First identified by Samuel Wilks in 1852, trichorrhexis nodosa (TN) is a congenital or acquired hair shaft disorder that is characterized by fragile and easily broken hair.¹ Congenital TN is rare and can occur in syndromes such as pseudomonilethrix, Netherton syndrome, pili annulati,² argininosuccinic aciduria,³ trichothiodystrophy,⁴ Menkes syndrome,⁵ and trichohepatoenteric syndrome.⁶ The primary congenital form of TN is inherited as an autosomal-dominant trait in some families. Acquired TN is the most common hair shaft abnormality and often is overlooked. It is provoked by hair injury, usually mechanical or physical, or chemical trauma.^7,8

Chemical trauma is caused by the use of permanent hair liquids or dyes. Mechanical injuries are the result of frequent brushing, scalp massage, or lengthy backcombing, and physical damage includes excessive UV exposure or repeated application of heat. Habit tics, trichotillomania, and the scratching and pulling associated with pruritic dermatoses also can result in sufficient damage to provoke TN. Furthermore, this acquired disorder may develop from malnutrition, particularly iron deficiency, or endocrinopathy such as hypothyroidism.⁹ Seasonal recurrence of TN has been reported from the cumulative effect of repeated soaking in salt water and exposure to UV light. Macroscopically, hair shafts affected by TN contain small white nodes at irregular intervals throughout the length of the hair shaft. These nodes represent areas of cuticular cell disruption, which allows the underlying cortical fibers to separate and fray and gives the node the microscopic appearance of 2 brooms or paintbrushes thrusting together end-to-end by the bristles. The classic description is known as paintbrush fracture.¹⁰ Generally, complete breakage occurs at these nodes.

A 21-year-old white woman presented to our clinic with hair fragility and inability to grow long hair of 2 years’ duration. The hair was lusterless and dry. Dermoscopic examination revealed broken blunt-ended hair of uneven length with minute pinpoint grayish white nodules (Figure 1). Small fragments could be easily broken off with gentle tugging on the distal ends. She reported a history of severe sunlight and seawater exposure during the last 2 summers and the continuous use of a flat iron in the last year. Microscopic examination of hair samples with a scanning electron microscope showed the characteristic paintbrush fracture (Figure 2). She had no history of diseases, and blood examinations including complete blood cell count, thyroid function test, and iron levels were within reference range.

Figure 1. Dermoscopy revealed broken blunt-ended hair of uneven length with minute pinpoint grayish white nodules (original magnification ×30). Figure 2. Scanning electron microscopy showed characteristic paintbrush fracture of the hair shaft (original magnification ×748).

We hypothesize that the seasonal damage caused by exposure to UV light and salt water with repeated trauma from the heat of the flat iron caused distal TN. The patient was given an explanation about the diagnosis of TN and was instructed to avoid the practices that were suspected causes of the condition. Use of a gentle shampoo and conditioner also was recommended. At 6-month follow-up, we noticed an improvement of the quality of hair with a reduction in the whitish nodules and a revival of hair growth.

Acquired TN has been classified into 3 clinical forms: proximal, distal, and localized.¹ Proximal TN is common in black individuals who use caustic chemicals when styling the hair. The involved hairs develop the characteristic nodes that break within a few centimeters from the scalp, especially in areas subject to friction from combing or sleeping. Distal TN primarily occurs in white or Asian individuals. In this disorder, nodes and breakage occur near the ends of the hairs that appear dull, dry, and uneven. Breakage commonly is associated with trichoptilosis, or longitudinal splitting, commonly referred to as split ends. This breakage may reflect frequent use of shampoo or heat treatments. The distal acquired form may simulate dandruff or pediculosis and the detection of this hair defect often is casual.

Localized TN, described by Raymond Sabouraud in 1921, is a rare disorder. It occurs in a patch that is usually a few centimeters long. It generally is accompanied by a pruritic dermatosis, such as circumscribed neurodermatitis, contact dermatitis, or atopic dermatitis. Scratching and rubbing most likely are the ultimate causes.

Trichorrhexis nodosa can spontaneously resolve. In all cases, diagnosis depends on careful microscopy examination and, if possible, scanning electron microscopy. Treatment is aimed at minimizing mechanical and physical injury, and chemical trauma. Excessive brushing, hot-combing, permanent waving, and other harsh hair treatments should be avoided. If the hair is long and the damage is distal, it may be sufficient to cut the distal fraction and to change cosmetic practices to prevent relapse.

Dermatologists who see patients with hair fragility and inability to grow long hair should consider the diagnosis of TN. Acquired TN often is reversible. Complete resolution may take 2 to 4 years depending on the growth of new anagen hairs. All patients with a history of white flecking on the scalp, abnormal fragility of the hair, and failure to attain normal hair length should be questioned about their routine hair care habits as well as environmental or chemical exposures to determine and remove the source of physical or chemical trauma.

A 30-year-old woman cuts her finger on a glass jar. She goes to the clinic and needs to have sutures on her right ring finger. What would you recommend for anesthesia to prepare the patient for repair?

A. 1% lidocaine.

B. 1% lidocaine with epinephrine.

C. Bupivacaine.

Myth: You should not use lidocaine with epinephrine on a digit.

Many of us were taught to avoid the use of epinephrine on digits because of the concern of precipitating digital ischemia. This was a common warning in emergency and surgical textbooks (J.C. Vance. Anesthesia. R.K. Roenigk, H.H. Roenigk [Eds.], Dermatologic Surgery, Principles and Practice [2nd ed.], Marcel Decker, New York, N.Y. [1996], pp. 31-52.).

Over the past 20 years, there has been a growing body of evidence that the concern is unwarranted and that there may be benefit to the addition of epinephrine.

Dr. Bradon J. Wilhelmi and his colleagues performed a randomized, double-blind trial comparing lidocaine with epinephrine (31 patients) and lidocaine (29 patients) in patients with traumatic injuries or elective procedures (Plast. Reconstr. Surg. 2001;107:393-7). The need for control of bleeding required digital tourniquet use in 20 of 29 block procedures with plain lidocaine and in 9 of 31 procedures using lidocaine with epinephrine (P < .002). There were no complications in the patients who received lidocaine with epinephrine.

A retrospective study was done by Dr. Saeed Chowdhry and his colleagues of 1,111 patients who had hand surgery and received digital blocks (Plast. Reconstr. Surg. 2010;126:2031-4). A total of 611 patients received lidocaine with epinephrine, and 500 patients received lidocaine alone. The concentration of lidocaine with epinephrine was 1:100,000, with an average dose of 4.33 cc.

There were no cases of digital gangrene or other complications because of the use of epinephrine in this retrospective study.

In a large, retrospective study of nine hand surgeons’ practices, looking at 3,110 cases of elective injection of low-dose epinephrine in hands and fingers, there were no cases of digital tissue loss or need for phentolamine rescue (J. Hand Surg. Am. 2005;30:1061-7).

Several studies have been done using epinephrine digital injections of the toes. In a prospective, randomized, controlled trial, 44 patients undergoing phenolization matricectomy involving digital block injection of 70 toes received either anesthetic and epinephrine or anesthetic and digital tourniquet (J. Eur. Acad. Dermatol. Venereol. 2014 [doi:10.1111/jdv.12746]). The outcome measures were rate of recurrence, bleeding, pain, and duration of anesthetic effect.

There was no difference in recurrence rates, but postoperative bleeding was higher in the procedures done with digital tourniquet and no epinephrine (P = .001). Anesthetic effect as measured by less pain and duration of effect was superior in the patients receiving digital block with epinephrine (P = .001).

In another study looking at chemical matricectomy, Dr. Cevdet Altinyazar and his colleagues randomized patients to receive either 2% lidocaine or lidocaine with epinephrine for anesthesia for chemical matricectomy of ingrown toenails of the great toe (Dermatol. Surg. 2010;36:1568-71). There was less anesthetic needed in the patients who received lidocaine with epinephrine, and a statistically significant reduction in days of drainage following procedure in the lidocaine with epinephrine group (11.1 days +/- 2.5 days), compared with the lidocaine-only group (19.0 days +/- 3.8 days). There were no complications because of the use of epinephrine.

The belief in this myth is still quite common, despite the evidence from randomized, controlled trials and the experience of more than 3,500 patients who have received epinephrine in the fingers without any complications. The evidence from the podiatry literature on safety in use in the toes mirrors the evidence of safety in the fingers.

Dr. Paauw is a professor of medicine in the division of general internal medicine at the University of Washington, Seattle, and he serves as third-year medical student clerkship director at the University of Washington Medical School. He is the Rathmann Family Foundation Chair in Patient-Centered Clinical Education. Contact Dr. Paauw at [email protected].

A 30-year-old woman cuts her finger on a glass jar. She goes to the clinic and needs to have sutures on her right ring finger. What would you recommend for anesthesia to prepare the patient for repair?

A. 1% lidocaine.

B. 1% lidocaine with epinephrine.

C. Bupivacaine.

Myth: You should not use lidocaine with epinephrine on a digit.

Many of us were taught to avoid the use of epinephrine on digits because of the concern of precipitating digital ischemia. This was a common warning in emergency and surgical textbooks (J.C. Vance. Anesthesia. R.K. Roenigk, H.H. Roenigk [Eds.], Dermatologic Surgery, Principles and Practice [2nd ed.], Marcel Decker, New York, N.Y. [1996], pp. 31-52.).

Over the past 20 years, there has been a growing body of evidence that the concern is unwarranted and that there may be benefit to the addition of epinephrine.

Dr. Bradon J. Wilhelmi and his colleagues performed a randomized, double-blind trial comparing lidocaine with epinephrine (31 patients) and lidocaine (29 patients) in patients with traumatic injuries or elective procedures (Plast. Reconstr. Surg. 2001;107:393-7). The need for control of bleeding required digital tourniquet use in 20 of 29 block procedures with plain lidocaine and in 9 of 31 procedures using lidocaine with epinephrine (P < .002). There were no complications in the patients who received lidocaine with epinephrine.

A retrospective study was done by Dr. Saeed Chowdhry and his colleagues of 1,111 patients who had hand surgery and received digital blocks (Plast. Reconstr. Surg. 2010;126:2031-4). A total of 611 patients received lidocaine with epinephrine, and 500 patients received lidocaine alone. The concentration of lidocaine with epinephrine was 1:100,000, with an average dose of 4.33 cc.

There were no cases of digital gangrene or other complications because of the use of epinephrine in this retrospective study.

In a large, retrospective study of nine hand surgeons’ practices, looking at 3,110 cases of elective injection of low-dose epinephrine in hands and fingers, there were no cases of digital tissue loss or need for phentolamine rescue (J. Hand Surg. Am. 2005;30:1061-7).

Several studies have been done using epinephrine digital injections of the toes. In a prospective, randomized, controlled trial, 44 patients undergoing phenolization matricectomy involving digital block injection of 70 toes received either anesthetic and epinephrine or anesthetic and digital tourniquet (J. Eur. Acad. Dermatol. Venereol. 2014 [doi:10.1111/jdv.12746]). The outcome measures were rate of recurrence, bleeding, pain, and duration of anesthetic effect.

There was no difference in recurrence rates, but postoperative bleeding was higher in the procedures done with digital tourniquet and no epinephrine (P = .001). Anesthetic effect as measured by less pain and duration of effect was superior in the patients receiving digital block with epinephrine (P = .001).

In another study looking at chemical matricectomy, Dr. Cevdet Altinyazar and his colleagues randomized patients to receive either 2% lidocaine or lidocaine with epinephrine for anesthesia for chemical matricectomy of ingrown toenails of the great toe (Dermatol. Surg. 2010;36:1568-71). There was less anesthetic needed in the patients who received lidocaine with epinephrine, and a statistically significant reduction in days of drainage following procedure in the lidocaine with epinephrine group (11.1 days +/- 2.5 days), compared with the lidocaine-only group (19.0 days +/- 3.8 days). There were no complications because of the use of epinephrine.

The belief in this myth is still quite common, despite the evidence from randomized, controlled trials and the experience of more than 3,500 patients who have received epinephrine in the fingers without any complications. The evidence from the podiatry literature on safety in use in the toes mirrors the evidence of safety in the fingers.

Dr. Paauw is a professor of medicine in the division of general internal medicine at the University of Washington, Seattle, and he serves as third-year medical student clerkship director at the University of Washington Medical School. He is the Rathmann Family Foundation Chair in Patient-Centered Clinical Education. Contact Dr. Paauw at [email protected].

A 30-year-old woman cuts her finger on a glass jar. She goes to the clinic and needs to have sutures on her right ring finger. What would you recommend for anesthesia to prepare the patient for repair?

A. 1% lidocaine.

B. 1% lidocaine with epinephrine.

C. Bupivacaine.

Myth: You should not use lidocaine with epinephrine on a digit.

Many of us were taught to avoid the use of epinephrine on digits because of the concern of precipitating digital ischemia. This was a common warning in emergency and surgical textbooks (J.C. Vance. Anesthesia. R.K. Roenigk, H.H. Roenigk [Eds.], Dermatologic Surgery, Principles and Practice [2nd ed.], Marcel Decker, New York, N.Y. [1996], pp. 31-52.).

Over the past 20 years, there has been a growing body of evidence that the concern is unwarranted and that there may be benefit to the addition of epinephrine.

Dr. Bradon J. Wilhelmi and his colleagues performed a randomized, double-blind trial comparing lidocaine with epinephrine (31 patients) and lidocaine (29 patients) in patients with traumatic injuries or elective procedures (Plast. Reconstr. Surg. 2001;107:393-7). The need for control of bleeding required digital tourniquet use in 20 of 29 block procedures with plain lidocaine and in 9 of 31 procedures using lidocaine with epinephrine (P < .002). There were no complications in the patients who received lidocaine with epinephrine.

A retrospective study was done by Dr. Saeed Chowdhry and his colleagues of 1,111 patients who had hand surgery and received digital blocks (Plast. Reconstr. Surg. 2010;126:2031-4). A total of 611 patients received lidocaine with epinephrine, and 500 patients received lidocaine alone. The concentration of lidocaine with epinephrine was 1:100,000, with an average dose of 4.33 cc.

There were no cases of digital gangrene or other complications because of the use of epinephrine in this retrospective study.

In a large, retrospective study of nine hand surgeons’ practices, looking at 3,110 cases of elective injection of low-dose epinephrine in hands and fingers, there were no cases of digital tissue loss or need for phentolamine rescue (J. Hand Surg. Am. 2005;30:1061-7).

Several studies have been done using epinephrine digital injections of the toes. In a prospective, randomized, controlled trial, 44 patients undergoing phenolization matricectomy involving digital block injection of 70 toes received either anesthetic and epinephrine or anesthetic and digital tourniquet (J. Eur. Acad. Dermatol. Venereol. 2014 [doi:10.1111/jdv.12746]). The outcome measures were rate of recurrence, bleeding, pain, and duration of anesthetic effect.

There was no difference in recurrence rates, but postoperative bleeding was higher in the procedures done with digital tourniquet and no epinephrine (P = .001). Anesthetic effect as measured by less pain and duration of effect was superior in the patients receiving digital block with epinephrine (P = .001).

In another study looking at chemical matricectomy, Dr. Cevdet Altinyazar and his colleagues randomized patients to receive either 2% lidocaine or lidocaine with epinephrine for anesthesia for chemical matricectomy of ingrown toenails of the great toe (Dermatol. Surg. 2010;36:1568-71). There was less anesthetic needed in the patients who received lidocaine with epinephrine, and a statistically significant reduction in days of drainage following procedure in the lidocaine with epinephrine group (11.1 days +/- 2.5 days), compared with the lidocaine-only group (19.0 days +/- 3.8 days). There were no complications because of the use of epinephrine.

The belief in this myth is still quite common, despite the evidence from randomized, controlled trials and the experience of more than 3,500 patients who have received epinephrine in the fingers without any complications. The evidence from the podiatry literature on safety in use in the toes mirrors the evidence of safety in the fingers.

Dr. Paauw is a professor of medicine in the division of general internal medicine at the University of Washington, Seattle, and he serves as third-year medical student clerkship director at the University of Washington Medical School. He is the Rathmann Family Foundation Chair in Patient-Centered Clinical Education. Contact Dr. Paauw at [email protected].