Photo Challenge

The Diagnosis: Nevus Lipomatosus Cutaneous Superficialis

A punch biopsy was obtained from a skin lesion, which showed orthokeratosis, irregular acanthosis, papillomatosis, intense edema in the upper dermis, and mature fat lobules that dissected collagen fibers in the reticular dermis (Figure). Classical-type nevus lipomatosus cutaneous superficialis (NLCS) was diagnosed based on these clinical and histopathological findings. The patient was referred to the plastic surgery clinic for total excision of all lesions.

Nevus lipomatosus cutaneous superficialis is a rare hamartoma characterized by ectopic deposition of mature adipose tissue in the dermis.¹ It was first described by Hoffmann and Zurhelle² in 1921. Clinically, NLCS is classified into 2 subtypes: classical (multiple) and solitary. Classical-type NLCS is characterized by multiple pedunculated or sessile, soft, cerebriform, yellowish papules and nodules, especially in the pelvic area. Solitary-type NLCS presents as a sessile papule or nodule with no predilection for localization. Although the classical form of NLCS generally occurs in the first 2 decades of life, the solitary form usually appears in adulthood.³ Nevus lipomatosus cutaneous superficialis has no gender predilection and there is no genetic or congenital defect association.^1,4

The pathogenesis of NLCS still is unknown, but some theories have been proposed, such as the development of adipose metaplasia secondary to degeneration of connective tissue, the formation of a true nevus resulting from heterotopic development of adipose tissue, and the development of mature adipocytes from pericytes in dermal vessels.^1,5 

Histopathology of NLCS shows clusters of ectopic mature adipose tissue in varying rates (10%-50%) between collagen bundles in the dermis. Characteristically, there is no connection between the ectopic mature adipose tissue and the subcutaneous adipose tissue.³ The differential diagnosis of NLCS includes neurofibroma, lymphangioma, sebaceous nevus, fibroepithelial polyps, leiomyoma, and lipomas.^1,6

Treatment of NLCS generally involves basic surgical excision; however, patients treated with CO₂ laser also have been reported in the literature.⁵ Because of the growth tendency and the large size of the classical form of NLCS, recurrence may occur, as in our case. In such cases, gradual surgical excision is recommended.⁵ We present this case to indicate that undesirable surgical results or relapse may occur in untreated patients because of lesion growth and delayed diagnosis.

The Diagnosis: Nevus Lipomatosus Cutaneous Superficialis

A punch biopsy was obtained from a skin lesion, which showed orthokeratosis, irregular acanthosis, papillomatosis, intense edema in the upper dermis, and mature fat lobules that dissected collagen fibers in the reticular dermis (Figure). Classical-type nevus lipomatosus cutaneous superficialis (NLCS) was diagnosed based on these clinical and histopathological findings. The patient was referred to the plastic surgery clinic for total excision of all lesions.

Nevus lipomatosus cutaneous superficialis is a rare hamartoma characterized by ectopic deposition of mature adipose tissue in the dermis.¹ It was first described by Hoffmann and Zurhelle² in 1921. Clinically, NLCS is classified into 2 subtypes: classical (multiple) and solitary. Classical-type NLCS is characterized by multiple pedunculated or sessile, soft, cerebriform, yellowish papules and nodules, especially in the pelvic area. Solitary-type NLCS presents as a sessile papule or nodule with no predilection for localization. Although the classical form of NLCS generally occurs in the first 2 decades of life, the solitary form usually appears in adulthood.³ Nevus lipomatosus cutaneous superficialis has no gender predilection and there is no genetic or congenital defect association.^1,4

The pathogenesis of NLCS still is unknown, but some theories have been proposed, such as the development of adipose metaplasia secondary to degeneration of connective tissue, the formation of a true nevus resulting from heterotopic development of adipose tissue, and the development of mature adipocytes from pericytes in dermal vessels.^1,5 

Histopathology of NLCS shows clusters of ectopic mature adipose tissue in varying rates (10%-50%) between collagen bundles in the dermis. Characteristically, there is no connection between the ectopic mature adipose tissue and the subcutaneous adipose tissue.³ The differential diagnosis of NLCS includes neurofibroma, lymphangioma, sebaceous nevus, fibroepithelial polyps, leiomyoma, and lipomas.^1,6

Treatment of NLCS generally involves basic surgical excision; however, patients treated with CO₂ laser also have been reported in the literature.⁵ Because of the growth tendency and the large size of the classical form of NLCS, recurrence may occur, as in our case. In such cases, gradual surgical excision is recommended.⁵ We present this case to indicate that undesirable surgical results or relapse may occur in untreated patients because of lesion growth and delayed diagnosis.

The Diagnosis: Nevus Lipomatosus Cutaneous Superficialis

A punch biopsy was obtained from a skin lesion, which showed orthokeratosis, irregular acanthosis, papillomatosis, intense edema in the upper dermis, and mature fat lobules that dissected collagen fibers in the reticular dermis (Figure). Classical-type nevus lipomatosus cutaneous superficialis (NLCS) was diagnosed based on these clinical and histopathological findings. The patient was referred to the plastic surgery clinic for total excision of all lesions.

Nevus lipomatosus cutaneous superficialis is a rare hamartoma characterized by ectopic deposition of mature adipose tissue in the dermis.¹ It was first described by Hoffmann and Zurhelle² in 1921. Clinically, NLCS is classified into 2 subtypes: classical (multiple) and solitary. Classical-type NLCS is characterized by multiple pedunculated or sessile, soft, cerebriform, yellowish papules and nodules, especially in the pelvic area. Solitary-type NLCS presents as a sessile papule or nodule with no predilection for localization. Although the classical form of NLCS generally occurs in the first 2 decades of life, the solitary form usually appears in adulthood.³ Nevus lipomatosus cutaneous superficialis has no gender predilection and there is no genetic or congenital defect association.^1,4

The pathogenesis of NLCS still is unknown, but some theories have been proposed, such as the development of adipose metaplasia secondary to degeneration of connective tissue, the formation of a true nevus resulting from heterotopic development of adipose tissue, and the development of mature adipocytes from pericytes in dermal vessels.^1,5 

Histopathology of NLCS shows clusters of ectopic mature adipose tissue in varying rates (10%-50%) between collagen bundles in the dermis. Characteristically, there is no connection between the ectopic mature adipose tissue and the subcutaneous adipose tissue.³ The differential diagnosis of NLCS includes neurofibroma, lymphangioma, sebaceous nevus, fibroepithelial polyps, leiomyoma, and lipomas.^1,6

Treatment of NLCS generally involves basic surgical excision; however, patients treated with CO₂ laser also have been reported in the literature.⁵ Because of the growth tendency and the large size of the classical form of NLCS, recurrence may occur, as in our case. In such cases, gradual surgical excision is recommended.⁵ We present this case to indicate that undesirable surgical results or relapse may occur in untreated patients because of lesion growth and delayed diagnosis.

The Diagnosis: Langerhans Cell Histiocytosis 

Langerhans cell histiocytosis (LCH) is a clonal proliferative disorder of Langerhans cells that can affect any organ, most commonly the skin and bones. It typically develops in children aged 1 to 3 years, with a male to female ratio of 2 to 1.¹ Skin manifestations include purpuric papules, pustules, vesicles, erosions, and fissuring distributed predominantly on the scalp and flexural sites. Mucosal sites, particularly the oral mucosa, may be involved and usually present as erosions associated with underlying bone lesions.¹ Langerhans cell histiocytosis should be considered in the differential diagnosis of recalcitrant diaper dermatitis in an infant, especially when there is purpura and erosions, as seen in our patient. Common conditions in infants such as cutaneous candidiasis (intense erythema with superficial erosions, peripheral scale and satellite pustules on flexural areas, potassium hydroxide microscopy revealing yeast forms and pseudohyphae) and seborrheic dermatitis (well-defined pink to red, moist, and often scaly patches favoring the folds) may be distinguished clinically from Hailey-Hailey disease (malodorous plaques with fissures and erosions favoring the folds), which is rare in infancy, and acrodermatitis enteropathica (erythema and erosions with scale-crust and desquamation on periorificial, acral, and intertriginous skin).

Histopathologic evaluation is instrumental in diagnosing the skin lesions of LCH. Further evaluation for systemic involvement is necessary once the diagnosis is made. Skin biopsy of the scalp and right inguinal fold revealed a wedge-shaped infiltrate of histiocytes with slightly folded nuclear contours in our patient (Figure 1). CD1a (Figure 2) and S-100 stains were markedly positive, which is characteristic of LCH. Complete blood cell count, renal function, liver function, urinalysis, and flow cytometry results were within reference range. A skeletal survey and echocardiogram were unremarkable; however, mild hepatosplenomegaly was noted on abdominal ultrasonography.

Treatment of LCH varies based on the extent of organ involvement. For isolated cutaneous disease, topical steroids, topical nitrogen mustard, phototherapy, and thalidomide may be employed.² Multisystem disease requires chemotherapeutic agents including vinblastine and prednisone.^2,3 Because more than half of patients with LCH have oncogenic BRAF V600E mutations,⁴ vemurafenib may have a therapeutic role in treatment. Rare case reports have documented disease response in patients with LCH and Erdheim-Chester disease.^5,6 

Prognosis varies based on age and extent of systemic involvement. Children younger than 2 years with multiorgan involvement have a poor prognosis (35%-55% mortality rate) compared to older children without hematopoietic, hepatosplenic, or lung involvement (100% survival rate). Additionally, response to treatment affects prognosis, as there is a 66% mortality rate in those who do not respond to treatment after 6 weeks.³ Long-term sequelae of LCH include endocrine dysfunction (ie, diabetes insipidus, growth hormone deficiencies), hearing impairment, orthopedic impairment, and neuropsychological disease; thus, multidisciplinary care often is neccessary.⁷

Given the multisystem involvement in our patient, he was treated with vinblastine, 6-mercaptopurine, and prednisolone with only partial and transient disease response. He was then treated with clofarabine with dramatic resolution of the mediastinal mass on follow-up positron emission tomography. The cutaneous lesions persisted and were managed with topical corticosteroids.

The Diagnosis: Langerhans Cell Histiocytosis 

Langerhans cell histiocytosis (LCH) is a clonal proliferative disorder of Langerhans cells that can affect any organ, most commonly the skin and bones. It typically develops in children aged 1 to 3 years, with a male to female ratio of 2 to 1.¹ Skin manifestations include purpuric papules, pustules, vesicles, erosions, and fissuring distributed predominantly on the scalp and flexural sites. Mucosal sites, particularly the oral mucosa, may be involved and usually present as erosions associated with underlying bone lesions.¹ Langerhans cell histiocytosis should be considered in the differential diagnosis of recalcitrant diaper dermatitis in an infant, especially when there is purpura and erosions, as seen in our patient. Common conditions in infants such as cutaneous candidiasis (intense erythema with superficial erosions, peripheral scale and satellite pustules on flexural areas, potassium hydroxide microscopy revealing yeast forms and pseudohyphae) and seborrheic dermatitis (well-defined pink to red, moist, and often scaly patches favoring the folds) may be distinguished clinically from Hailey-Hailey disease (malodorous plaques with fissures and erosions favoring the folds), which is rare in infancy, and acrodermatitis enteropathica (erythema and erosions with scale-crust and desquamation on periorificial, acral, and intertriginous skin).

Histopathologic evaluation is instrumental in diagnosing the skin lesions of LCH. Further evaluation for systemic involvement is necessary once the diagnosis is made. Skin biopsy of the scalp and right inguinal fold revealed a wedge-shaped infiltrate of histiocytes with slightly folded nuclear contours in our patient (Figure 1). CD1a (Figure 2) and S-100 stains were markedly positive, which is characteristic of LCH. Complete blood cell count, renal function, liver function, urinalysis, and flow cytometry results were within reference range. A skeletal survey and echocardiogram were unremarkable; however, mild hepatosplenomegaly was noted on abdominal ultrasonography.

Treatment of LCH varies based on the extent of organ involvement. For isolated cutaneous disease, topical steroids, topical nitrogen mustard, phototherapy, and thalidomide may be employed.² Multisystem disease requires chemotherapeutic agents including vinblastine and prednisone.^2,3 Because more than half of patients with LCH have oncogenic BRAF V600E mutations,⁴ vemurafenib may have a therapeutic role in treatment. Rare case reports have documented disease response in patients with LCH and Erdheim-Chester disease.^5,6 

Prognosis varies based on age and extent of systemic involvement. Children younger than 2 years with multiorgan involvement have a poor prognosis (35%-55% mortality rate) compared to older children without hematopoietic, hepatosplenic, or lung involvement (100% survival rate). Additionally, response to treatment affects prognosis, as there is a 66% mortality rate in those who do not respond to treatment after 6 weeks.³ Long-term sequelae of LCH include endocrine dysfunction (ie, diabetes insipidus, growth hormone deficiencies), hearing impairment, orthopedic impairment, and neuropsychological disease; thus, multidisciplinary care often is neccessary.⁷

Given the multisystem involvement in our patient, he was treated with vinblastine, 6-mercaptopurine, and prednisolone with only partial and transient disease response. He was then treated with clofarabine with dramatic resolution of the mediastinal mass on follow-up positron emission tomography. The cutaneous lesions persisted and were managed with topical corticosteroids.

The Diagnosis: Langerhans Cell Histiocytosis 

Langerhans cell histiocytosis (LCH) is a clonal proliferative disorder of Langerhans cells that can affect any organ, most commonly the skin and bones. It typically develops in children aged 1 to 3 years, with a male to female ratio of 2 to 1.¹ Skin manifestations include purpuric papules, pustules, vesicles, erosions, and fissuring distributed predominantly on the scalp and flexural sites. Mucosal sites, particularly the oral mucosa, may be involved and usually present as erosions associated with underlying bone lesions.¹ Langerhans cell histiocytosis should be considered in the differential diagnosis of recalcitrant diaper dermatitis in an infant, especially when there is purpura and erosions, as seen in our patient. Common conditions in infants such as cutaneous candidiasis (intense erythema with superficial erosions, peripheral scale and satellite pustules on flexural areas, potassium hydroxide microscopy revealing yeast forms and pseudohyphae) and seborrheic dermatitis (well-defined pink to red, moist, and often scaly patches favoring the folds) may be distinguished clinically from Hailey-Hailey disease (malodorous plaques with fissures and erosions favoring the folds), which is rare in infancy, and acrodermatitis enteropathica (erythema and erosions with scale-crust and desquamation on periorificial, acral, and intertriginous skin).

Histopathologic evaluation is instrumental in diagnosing the skin lesions of LCH. Further evaluation for systemic involvement is necessary once the diagnosis is made. Skin biopsy of the scalp and right inguinal fold revealed a wedge-shaped infiltrate of histiocytes with slightly folded nuclear contours in our patient (Figure 1). CD1a (Figure 2) and S-100 stains were markedly positive, which is characteristic of LCH. Complete blood cell count, renal function, liver function, urinalysis, and flow cytometry results were within reference range. A skeletal survey and echocardiogram were unremarkable; however, mild hepatosplenomegaly was noted on abdominal ultrasonography.

Treatment of LCH varies based on the extent of organ involvement. For isolated cutaneous disease, topical steroids, topical nitrogen mustard, phototherapy, and thalidomide may be employed.² Multisystem disease requires chemotherapeutic agents including vinblastine and prednisone.^2,3 Because more than half of patients with LCH have oncogenic BRAF V600E mutations,⁴ vemurafenib may have a therapeutic role in treatment. Rare case reports have documented disease response in patients with LCH and Erdheim-Chester disease.^5,6 

Prognosis varies based on age and extent of systemic involvement. Children younger than 2 years with multiorgan involvement have a poor prognosis (35%-55% mortality rate) compared to older children without hematopoietic, hepatosplenic, or lung involvement (100% survival rate). Additionally, response to treatment affects prognosis, as there is a 66% mortality rate in those who do not respond to treatment after 6 weeks.³ Long-term sequelae of LCH include endocrine dysfunction (ie, diabetes insipidus, growth hormone deficiencies), hearing impairment, orthopedic impairment, and neuropsychological disease; thus, multidisciplinary care often is neccessary.⁷

Given the multisystem involvement in our patient, he was treated with vinblastine, 6-mercaptopurine, and prednisolone with only partial and transient disease response. He was then treated with clofarabine with dramatic resolution of the mediastinal mass on follow-up positron emission tomography. The cutaneous lesions persisted and were managed with topical corticosteroids.

The Diagnosis: Disseminate and Recurrent Infundibulofolliculitis

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

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

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

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

The Diagnosis: Disseminate and Recurrent Infundibulofolliculitis

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

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

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

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

The Diagnosis: Disseminate and Recurrent Infundibulofolliculitis

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

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

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

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

The Diagnosis: Toxicodendron Dermatitis

Toxicodendron dermatitis is an allergic contact dermatitis that can occur after exposure to a plant from the Toxicodendron genus including poison ivy (Toxicodendron radicans), poison oak (Toxicodendron diversilobum), and poison sumac (Toxicodendron vernix). These plants produce urushiol in their oleoresinous sap, which causes intense pruritus, streaks of erythema, and edematous papules followed by vesicles and bullae. Previously sensitized individuals develop symptoms as quickly as 24 to 48 hours after exposure, with a range of 5 hours to 15 days.^1-3 Rarely, black spots also can be found on the skin, most prominently after 72 hours of exposure.⁴

The color change of urushiol-containing sap from pale to black was first documented by Peter Kalm, a Swedish botanist who traveled to North America in the 1700s.⁵ The black-spot test can be used to identify Toxicodendron species because the sap will turn black when expressed on white paper after a few minutes.⁶ Manifestation of black lacquer streaks on the skin is rare because concentrated sap is necessary, which typically requires an unusually prolonged exposure with Toxicodendron plants.⁷

Without treatment, typical Toxicodendron dermatitis resolves in approximately 3 weeks, though it may take up to 6 weeks to clear.² Early intervention is critical, as urushiol will fully absorb after 30 minutes.² After contact, complete removal of the oleoresin by washing with mild soap and water within 10 minutes can prevent dermatitis. Early topical corticosteroid application can reduce erythema and pruritus. Extensive or severe involvement, which includes Toxicodendron dermatitis with black spots, is treated with systemic corticosteroids such as prednisone that is tapered over 2 to 3 weeks.¹

Our patient had classic findings of Toxicodendron dermatitis; however, initially there was concern for levamisole toxicity by the emergency department, as well-demarcated purpuric or dark skin lesions can be due to morbid conditions such as leukocytoclastic vasculitis or skin necrosis from drug toxicities or infectious etiologies. Dermatology was consulted and these concerns were alleviated on closer skin examination and further questioning. The patient reported that he spent several hours cutting brush that was known to be T vernix (poison sumac) 3 days prior to presentation. Interestingly, the patient did not have similar black streaks on the left side of the face, as he held the weed-trimming saw in his right hand and in effect protected the left side of the face from debris. Furthermore, he had pruritic erythematous plaques on both forearms. The facial black lacquer-like streaks were the result of urushiol oxidation in the setting of prolonged exposure to the poison sumac oleoresin sap during weed trimming. After dermatologic evaluation, the patient was discharged from the emergency department on a 15-day taper of oral prednisone, and he was instructed to wash involved areas and exposed clothing with soap and water, which led to complete resolution.

The Diagnosis: Toxicodendron Dermatitis

Toxicodendron dermatitis is an allergic contact dermatitis that can occur after exposure to a plant from the Toxicodendron genus including poison ivy (Toxicodendron radicans), poison oak (Toxicodendron diversilobum), and poison sumac (Toxicodendron vernix). These plants produce urushiol in their oleoresinous sap, which causes intense pruritus, streaks of erythema, and edematous papules followed by vesicles and bullae. Previously sensitized individuals develop symptoms as quickly as 24 to 48 hours after exposure, with a range of 5 hours to 15 days.^1-3 Rarely, black spots also can be found on the skin, most prominently after 72 hours of exposure.⁴

The color change of urushiol-containing sap from pale to black was first documented by Peter Kalm, a Swedish botanist who traveled to North America in the 1700s.⁵ The black-spot test can be used to identify Toxicodendron species because the sap will turn black when expressed on white paper after a few minutes.⁶ Manifestation of black lacquer streaks on the skin is rare because concentrated sap is necessary, which typically requires an unusually prolonged exposure with Toxicodendron plants.⁷

Without treatment, typical Toxicodendron dermatitis resolves in approximately 3 weeks, though it may take up to 6 weeks to clear.² Early intervention is critical, as urushiol will fully absorb after 30 minutes.² After contact, complete removal of the oleoresin by washing with mild soap and water within 10 minutes can prevent dermatitis. Early topical corticosteroid application can reduce erythema and pruritus. Extensive or severe involvement, which includes Toxicodendron dermatitis with black spots, is treated with systemic corticosteroids such as prednisone that is tapered over 2 to 3 weeks.¹

Our patient had classic findings of Toxicodendron dermatitis; however, initially there was concern for levamisole toxicity by the emergency department, as well-demarcated purpuric or dark skin lesions can be due to morbid conditions such as leukocytoclastic vasculitis or skin necrosis from drug toxicities or infectious etiologies. Dermatology was consulted and these concerns were alleviated on closer skin examination and further questioning. The patient reported that he spent several hours cutting brush that was known to be T vernix (poison sumac) 3 days prior to presentation. Interestingly, the patient did not have similar black streaks on the left side of the face, as he held the weed-trimming saw in his right hand and in effect protected the left side of the face from debris. Furthermore, he had pruritic erythematous plaques on both forearms. The facial black lacquer-like streaks were the result of urushiol oxidation in the setting of prolonged exposure to the poison sumac oleoresin sap during weed trimming. After dermatologic evaluation, the patient was discharged from the emergency department on a 15-day taper of oral prednisone, and he was instructed to wash involved areas and exposed clothing with soap and water, which led to complete resolution.

The Diagnosis: Toxicodendron Dermatitis

Toxicodendron dermatitis is an allergic contact dermatitis that can occur after exposure to a plant from the Toxicodendron genus including poison ivy (Toxicodendron radicans), poison oak (Toxicodendron diversilobum), and poison sumac (Toxicodendron vernix). These plants produce urushiol in their oleoresinous sap, which causes intense pruritus, streaks of erythema, and edematous papules followed by vesicles and bullae. Previously sensitized individuals develop symptoms as quickly as 24 to 48 hours after exposure, with a range of 5 hours to 15 days.^1-3 Rarely, black spots also can be found on the skin, most prominently after 72 hours of exposure.⁴

The color change of urushiol-containing sap from pale to black was first documented by Peter Kalm, a Swedish botanist who traveled to North America in the 1700s.⁵ The black-spot test can be used to identify Toxicodendron species because the sap will turn black when expressed on white paper after a few minutes.⁶ Manifestation of black lacquer streaks on the skin is rare because concentrated sap is necessary, which typically requires an unusually prolonged exposure with Toxicodendron plants.⁷

Without treatment, typical Toxicodendron dermatitis resolves in approximately 3 weeks, though it may take up to 6 weeks to clear.² Early intervention is critical, as urushiol will fully absorb after 30 minutes.² After contact, complete removal of the oleoresin by washing with mild soap and water within 10 minutes can prevent dermatitis. Early topical corticosteroid application can reduce erythema and pruritus. Extensive or severe involvement, which includes Toxicodendron dermatitis with black spots, is treated with systemic corticosteroids such as prednisone that is tapered over 2 to 3 weeks.¹

Our patient had classic findings of Toxicodendron dermatitis; however, initially there was concern for levamisole toxicity by the emergency department, as well-demarcated purpuric or dark skin lesions can be due to morbid conditions such as leukocytoclastic vasculitis or skin necrosis from drug toxicities or infectious etiologies. Dermatology was consulted and these concerns were alleviated on closer skin examination and further questioning. The patient reported that he spent several hours cutting brush that was known to be T vernix (poison sumac) 3 days prior to presentation. Interestingly, the patient did not have similar black streaks on the left side of the face, as he held the weed-trimming saw in his right hand and in effect protected the left side of the face from debris. Furthermore, he had pruritic erythematous plaques on both forearms. The facial black lacquer-like streaks were the result of urushiol oxidation in the setting of prolonged exposure to the poison sumac oleoresin sap during weed trimming. After dermatologic evaluation, the patient was discharged from the emergency department on a 15-day taper of oral prednisone, and he was instructed to wash involved areas and exposed clothing with soap and water, which led to complete resolution.

The Diagnosis: Pagetoid Reticulosis

Histopathologic examination demonstrated a dense infiltrate and psoriasiform pattern epidermal hyperplasia (Figure, A). There was conspicuous epidermotropism of moderately enlarged, hyperchromatic lymphocytes. Intraepidermal lymphocytes were slightly larger, darker, and more convoluted than those in the subjacent dermis (Figure, B). These cells exhibited CD3⁺ T-cell differentiation with an abnormal CD4-CD7-CD8- phenotype (Figure, C). The histopathologic finding of atypical epidermotropic T-cell infiltrate was compatible with a rare variant of mycosis fungoides known as pagetoid reticulosis (PR). After discussing the diagnosis and treatment options, the patient elected to begin with a conservative approach to therapy. We prescribed fluocinonide ointment 0.05% twice daily under occlusion. At 1 month follow-up, the patient experienced marked improvement of the erythema and scaling of the lesion.

Pagetoid reticulosis is a primary cutaneous T-cell lymphoma that has been categorized as an indolent localized variant of mycosis fungoides. This rare skin disorder was originally described by Woringer and Kolopp in 1939¹ and was further renamed in 1973 by Braun-Falco et al.² At that time the term pagetoid reticulosis was introduced due to similarities in histopathologic findings seen in Paget disease of the nipple. Two variants of the disease have been described since then: the localized type and the disseminated type. The localized type, also known as Woringer-Kolopp disease (WKD), typically presents as a persistent, sharply localized, scaly patch that slowly expands over several years. The lesion is classically located on the extensor surface of the hand or foot and often is asymptomatic. Due to the benign presentation, WKD can easily be confused with much more common diseases, such as psoriasis or fungal infections, resulting in a substantial delay in the diagnosis. The patient will often report a medical history notable for frequent office visits and numerous failed therapies. Even though it is exceedingly uncommon, these findings should prompt the practitioner to add WKD to their differential. The disseminated type of PR (also known as Ketron-Goodman disease) is characterized by diffuse cutaneous involvement, carries a much more progressive course, and often leads to a poor outcome.³ The histopathologic features of WKD and Ketron-Goodman disease are identical, and the 2 types are distinguished on clinical grounds alone.

Histopathologic features of PR are unique and often distinct in comparison to mycosis fungoides. Pagetoid reticulosis often is described as epidermal hyperplasia with parakeratosis, prominent acanthosis, and excessive epidermotropism of atypical lymphocytes scattered throughout the epidermis.³ The distinct pattern of epidermotropism seen in PR is the characteristic finding. Review of immunocytochemistry from reported cases has shown that CD marker expression of neoplastic T cells in PR can be variable in nature.⁴ Although it is known that immunophenotyping can be useful in diagnosing and distinguishing PR from other types of primary cutaneous T-cell lymphoma, the clinical significance of the observed phenotypic variation remains a mystery. As of now, it appears to be prognostically irrelevant.⁵

There are numerous therapeutic options available for PR. Depending on the size and extent of the disease, surgical excision and radiotherapy may be an option and are the most effective.⁶ For patients who are not good candidates or opt out of these options, there are various pharmacotherapies that also have proven to work. Traditional therapies include topical corticosteroids, corticosteroid injections, and phototherapy. However, more recent trials with retinoids, such as alitretinoin or bexarotene, appear to offer a promising therapeutic approach.⁷

Pagetoid reticulosis is a true malignant lymphoma of T-cell lineage, but it typically carries an excellent prognosis. Rare cases have been reported to progress to disseminated lymphoma.⁸ Therefore, long-term follow-up for a patient diagnosed with PR is recommended.

The Diagnosis: Pagetoid Reticulosis

Histopathologic examination demonstrated a dense infiltrate and psoriasiform pattern epidermal hyperplasia (Figure, A). There was conspicuous epidermotropism of moderately enlarged, hyperchromatic lymphocytes. Intraepidermal lymphocytes were slightly larger, darker, and more convoluted than those in the subjacent dermis (Figure, B). These cells exhibited CD3⁺ T-cell differentiation with an abnormal CD4-CD7-CD8- phenotype (Figure, C). The histopathologic finding of atypical epidermotropic T-cell infiltrate was compatible with a rare variant of mycosis fungoides known as pagetoid reticulosis (PR). After discussing the diagnosis and treatment options, the patient elected to begin with a conservative approach to therapy. We prescribed fluocinonide ointment 0.05% twice daily under occlusion. At 1 month follow-up, the patient experienced marked improvement of the erythema and scaling of the lesion.

Pagetoid reticulosis is a primary cutaneous T-cell lymphoma that has been categorized as an indolent localized variant of mycosis fungoides. This rare skin disorder was originally described by Woringer and Kolopp in 1939¹ and was further renamed in 1973 by Braun-Falco et al.² At that time the term pagetoid reticulosis was introduced due to similarities in histopathologic findings seen in Paget disease of the nipple. Two variants of the disease have been described since then: the localized type and the disseminated type. The localized type, also known as Woringer-Kolopp disease (WKD), typically presents as a persistent, sharply localized, scaly patch that slowly expands over several years. The lesion is classically located on the extensor surface of the hand or foot and often is asymptomatic. Due to the benign presentation, WKD can easily be confused with much more common diseases, such as psoriasis or fungal infections, resulting in a substantial delay in the diagnosis. The patient will often report a medical history notable for frequent office visits and numerous failed therapies. Even though it is exceedingly uncommon, these findings should prompt the practitioner to add WKD to their differential. The disseminated type of PR (also known as Ketron-Goodman disease) is characterized by diffuse cutaneous involvement, carries a much more progressive course, and often leads to a poor outcome.³ The histopathologic features of WKD and Ketron-Goodman disease are identical, and the 2 types are distinguished on clinical grounds alone.

Histopathologic features of PR are unique and often distinct in comparison to mycosis fungoides. Pagetoid reticulosis often is described as epidermal hyperplasia with parakeratosis, prominent acanthosis, and excessive epidermotropism of atypical lymphocytes scattered throughout the epidermis.³ The distinct pattern of epidermotropism seen in PR is the characteristic finding. Review of immunocytochemistry from reported cases has shown that CD marker expression of neoplastic T cells in PR can be variable in nature.⁴ Although it is known that immunophenotyping can be useful in diagnosing and distinguishing PR from other types of primary cutaneous T-cell lymphoma, the clinical significance of the observed phenotypic variation remains a mystery. As of now, it appears to be prognostically irrelevant.⁵

There are numerous therapeutic options available for PR. Depending on the size and extent of the disease, surgical excision and radiotherapy may be an option and are the most effective.⁶ For patients who are not good candidates or opt out of these options, there are various pharmacotherapies that also have proven to work. Traditional therapies include topical corticosteroids, corticosteroid injections, and phototherapy. However, more recent trials with retinoids, such as alitretinoin or bexarotene, appear to offer a promising therapeutic approach.⁷

Pagetoid reticulosis is a true malignant lymphoma of T-cell lineage, but it typically carries an excellent prognosis. Rare cases have been reported to progress to disseminated lymphoma.⁸ Therefore, long-term follow-up for a patient diagnosed with PR is recommended.

The Diagnosis: Pagetoid Reticulosis

Histopathologic examination demonstrated a dense infiltrate and psoriasiform pattern epidermal hyperplasia (Figure, A). There was conspicuous epidermotropism of moderately enlarged, hyperchromatic lymphocytes. Intraepidermal lymphocytes were slightly larger, darker, and more convoluted than those in the subjacent dermis (Figure, B). These cells exhibited CD3⁺ T-cell differentiation with an abnormal CD4-CD7-CD8- phenotype (Figure, C). The histopathologic finding of atypical epidermotropic T-cell infiltrate was compatible with a rare variant of mycosis fungoides known as pagetoid reticulosis (PR). After discussing the diagnosis and treatment options, the patient elected to begin with a conservative approach to therapy. We prescribed fluocinonide ointment 0.05% twice daily under occlusion. At 1 month follow-up, the patient experienced marked improvement of the erythema and scaling of the lesion.

Pagetoid reticulosis is a primary cutaneous T-cell lymphoma that has been categorized as an indolent localized variant of mycosis fungoides. This rare skin disorder was originally described by Woringer and Kolopp in 1939¹ and was further renamed in 1973 by Braun-Falco et al.² At that time the term pagetoid reticulosis was introduced due to similarities in histopathologic findings seen in Paget disease of the nipple. Two variants of the disease have been described since then: the localized type and the disseminated type. The localized type, also known as Woringer-Kolopp disease (WKD), typically presents as a persistent, sharply localized, scaly patch that slowly expands over several years. The lesion is classically located on the extensor surface of the hand or foot and often is asymptomatic. Due to the benign presentation, WKD can easily be confused with much more common diseases, such as psoriasis or fungal infections, resulting in a substantial delay in the diagnosis. The patient will often report a medical history notable for frequent office visits and numerous failed therapies. Even though it is exceedingly uncommon, these findings should prompt the practitioner to add WKD to their differential. The disseminated type of PR (also known as Ketron-Goodman disease) is characterized by diffuse cutaneous involvement, carries a much more progressive course, and often leads to a poor outcome.³ The histopathologic features of WKD and Ketron-Goodman disease are identical, and the 2 types are distinguished on clinical grounds alone.

Histopathologic features of PR are unique and often distinct in comparison to mycosis fungoides. Pagetoid reticulosis often is described as epidermal hyperplasia with parakeratosis, prominent acanthosis, and excessive epidermotropism of atypical lymphocytes scattered throughout the epidermis.³ The distinct pattern of epidermotropism seen in PR is the characteristic finding. Review of immunocytochemistry from reported cases has shown that CD marker expression of neoplastic T cells in PR can be variable in nature.⁴ Although it is known that immunophenotyping can be useful in diagnosing and distinguishing PR from other types of primary cutaneous T-cell lymphoma, the clinical significance of the observed phenotypic variation remains a mystery. As of now, it appears to be prognostically irrelevant.⁵

There are numerous therapeutic options available for PR. Depending on the size and extent of the disease, surgical excision and radiotherapy may be an option and are the most effective.⁶ For patients who are not good candidates or opt out of these options, there are various pharmacotherapies that also have proven to work. Traditional therapies include topical corticosteroids, corticosteroid injections, and phototherapy. However, more recent trials with retinoids, such as alitretinoin or bexarotene, appear to offer a promising therapeutic approach.⁷

Pagetoid reticulosis is a true malignant lymphoma of T-cell lineage, but it typically carries an excellent prognosis. Rare cases have been reported to progress to disseminated lymphoma.⁸ Therefore, long-term follow-up for a patient diagnosed with PR is recommended.

The Diagnosis: Collision Tumor

Excisional biopsy and histopathological examination demonstrated a collision tumor composed of a benign intradermal melanocytic nevus, tumor of follicular infundibulum, and an underlying sclerosing epithelial neoplasm, with a differential diagnosis of desmoplastic trichoepithelioma, morpheaform basal cell carcinoma, and microcystic adnexal carcinoma (Figure).

Common acquired melanocytic nevus presents clinically as a macule, papule, or nodule with smooth regular borders. The pigmented variant displays an evenly distributed pigment on the lesion. Intradermal melanocytic nevus often presents as a flesh-colored nodule, as in our case. Histopathologically, benign intradermal nevus typically is composed of a proliferation of melanocytes that exhibit dispersion as they go deeper in the dermis and maturation that manifests as melanocytes becoming smaller and more spindled in the deeper portions of the lesion.¹ These 2 characteristics plus the bland cytology seen in the present case confirm the benign characteristic of this lesion (Figure, B).

In addition to the benign intradermal melanocytic nevus, an adjacent tumor of follicular infundibulum was noted. Tumor of follicular infundibulum is a rare adnexal tumor. It occurs frequently on the head and neck and shows some female predominance.^2,3 Multiple lesions and eruptive lesions are rare forms that also have been reported.⁴ Histopathologically, the tumor demonstrates an epithelial plate that is present in the papillary dermis and is connected to the epidermis at multiple points with attachment to the follicular outer root sheath. Peripheral palisading is characteristically present above an eosinophilic basement membrane (Figure, A). Rare reports have documented sebaceous and eccrine differentiation.^5,6

Tumor of follicular infundibulum has been reported to be associated with other tumors. Organoid nevus (nevus sebaceous), trichilemmal tumor, and fibroma have been reported to occur as a collision tumor with tumor of follicular infundibulum. An association with Cowden disease also has been described.⁷ Biopsies that represent partial samples should be interpreted cautiously, as step sections can reveal basal cell carcinoma.

The term sclerosing epithelial neoplasm describes tumors that share a paisley tielike epithelial pattern and sclerotic stroma. Small specimens often require clinicopathologic correlation (Figure, C). The differential diagnosis includes morpheaform basal cell carcinoma, desmoplastic trichoepithelioma, and microcystic adnexal carcinoma. A panel of stains using Ber-EP4, PHLDA1, cytokeratin 15, and cytokeratin 19 has been proposed to help differentiate these entities.⁸ CD34 and cytokeratin 20 also have been used with varying success in small specimens.^9,10

The Diagnosis: Collision Tumor

Excisional biopsy and histopathological examination demonstrated a collision tumor composed of a benign intradermal melanocytic nevus, tumor of follicular infundibulum, and an underlying sclerosing epithelial neoplasm, with a differential diagnosis of desmoplastic trichoepithelioma, morpheaform basal cell carcinoma, and microcystic adnexal carcinoma (Figure).

Common acquired melanocytic nevus presents clinically as a macule, papule, or nodule with smooth regular borders. The pigmented variant displays an evenly distributed pigment on the lesion. Intradermal melanocytic nevus often presents as a flesh-colored nodule, as in our case. Histopathologically, benign intradermal nevus typically is composed of a proliferation of melanocytes that exhibit dispersion as they go deeper in the dermis and maturation that manifests as melanocytes becoming smaller and more spindled in the deeper portions of the lesion.¹ These 2 characteristics plus the bland cytology seen in the present case confirm the benign characteristic of this lesion (Figure, B).

In addition to the benign intradermal melanocytic nevus, an adjacent tumor of follicular infundibulum was noted. Tumor of follicular infundibulum is a rare adnexal tumor. It occurs frequently on the head and neck and shows some female predominance.^2,3 Multiple lesions and eruptive lesions are rare forms that also have been reported.⁴ Histopathologically, the tumor demonstrates an epithelial plate that is present in the papillary dermis and is connected to the epidermis at multiple points with attachment to the follicular outer root sheath. Peripheral palisading is characteristically present above an eosinophilic basement membrane (Figure, A). Rare reports have documented sebaceous and eccrine differentiation.^5,6

Tumor of follicular infundibulum has been reported to be associated with other tumors. Organoid nevus (nevus sebaceous), trichilemmal tumor, and fibroma have been reported to occur as a collision tumor with tumor of follicular infundibulum. An association with Cowden disease also has been described.⁷ Biopsies that represent partial samples should be interpreted cautiously, as step sections can reveal basal cell carcinoma.

The term sclerosing epithelial neoplasm describes tumors that share a paisley tielike epithelial pattern and sclerotic stroma. Small specimens often require clinicopathologic correlation (Figure, C). The differential diagnosis includes morpheaform basal cell carcinoma, desmoplastic trichoepithelioma, and microcystic adnexal carcinoma. A panel of stains using Ber-EP4, PHLDA1, cytokeratin 15, and cytokeratin 19 has been proposed to help differentiate these entities.⁸ CD34 and cytokeratin 20 also have been used with varying success in small specimens.^9,10

The Diagnosis: Collision Tumor

Excisional biopsy and histopathological examination demonstrated a collision tumor composed of a benign intradermal melanocytic nevus, tumor of follicular infundibulum, and an underlying sclerosing epithelial neoplasm, with a differential diagnosis of desmoplastic trichoepithelioma, morpheaform basal cell carcinoma, and microcystic adnexal carcinoma (Figure).

Common acquired melanocytic nevus presents clinically as a macule, papule, or nodule with smooth regular borders. The pigmented variant displays an evenly distributed pigment on the lesion. Intradermal melanocytic nevus often presents as a flesh-colored nodule, as in our case. Histopathologically, benign intradermal nevus typically is composed of a proliferation of melanocytes that exhibit dispersion as they go deeper in the dermis and maturation that manifests as melanocytes becoming smaller and more spindled in the deeper portions of the lesion.¹ These 2 characteristics plus the bland cytology seen in the present case confirm the benign characteristic of this lesion (Figure, B).

In addition to the benign intradermal melanocytic nevus, an adjacent tumor of follicular infundibulum was noted. Tumor of follicular infundibulum is a rare adnexal tumor. It occurs frequently on the head and neck and shows some female predominance.^2,3 Multiple lesions and eruptive lesions are rare forms that also have been reported.⁴ Histopathologically, the tumor demonstrates an epithelial plate that is present in the papillary dermis and is connected to the epidermis at multiple points with attachment to the follicular outer root sheath. Peripheral palisading is characteristically present above an eosinophilic basement membrane (Figure, A). Rare reports have documented sebaceous and eccrine differentiation.^5,6

Tumor of follicular infundibulum has been reported to be associated with other tumors. Organoid nevus (nevus sebaceous), trichilemmal tumor, and fibroma have been reported to occur as a collision tumor with tumor of follicular infundibulum. An association with Cowden disease also has been described.⁷ Biopsies that represent partial samples should be interpreted cautiously, as step sections can reveal basal cell carcinoma.

The term sclerosing epithelial neoplasm describes tumors that share a paisley tielike epithelial pattern and sclerotic stroma. Small specimens often require clinicopathologic correlation (Figure, C). The differential diagnosis includes morpheaform basal cell carcinoma, desmoplastic trichoepithelioma, and microcystic adnexal carcinoma. A panel of stains using Ber-EP4, PHLDA1, cytokeratin 15, and cytokeratin 19 has been proposed to help differentiate these entities.⁸ CD34 and cytokeratin 20 also have been used with varying success in small specimens.^9,10

The Diagnosis: PELVIS Syndrome

Infantile hemangiomas (IHs) are present in up to 10% of infants by 1 year of age and are most commonly located on the face and upper extremities. Less than 10% of IHs develop in the perineum.¹ Perineal IHs are benign tumors of the vascular endothelium that present as plaques and commonly are accompanied by painful ulcerations. Ulceration is more common in the diaper area secondary to irritation from urine, stool, and friction.² Although most IHs are benign isolated findings, facial IHs have been associated with several syndromes including Sturge-Weber and PHACE (posterior fossa brain malformations, hemangiomas, arterial anomalies, cardiac anomalies and coarctation of the aorta, and eye and endocrine abnormalities) syndromes.³ Researchers also have identified an association between lumbosacral IHs and spinal dysraphism (tethered spinal cord).⁴

A smaller number of studies have investigated congenital anomalies related to perineal IH,^1,5 specifically PELVIS syndrome. The acronym PELVIS has been used to describe a syndrome of congenital malformations including perineal hemangioma, external genital malformations, lipomyelomeningocele, vesicorenal abnormalities, imperforate anus, and skin tag.¹ An alternative description of similar findings is LUMBAR (lower body hemangioma and other cutaneous defects; urogenital anomalies, ulceration; myelopathy; bony deformities; anorectal malformations, arterial anomalies; and renal anomalies).⁵ Researchers have suggested that both of these acronyms describe the same syndrome, and it is common for the syndrome to be incomplete.⁶ One study (N=11) found that perineal hemangiomas are most commonly associated with anal malformations (8 patients), followed by urinary tract abnormalities (7 patients) and malformation of the external genitalia (7 patients). A skin tag was present in 5 patients.¹ The pathogenesis of PELVIS syndrome is unknown.

When an infant presents with a perineal hemangioma and physical examination suggests PELVIS syndrome, imaging should be performed to evaluate for other anomalies. Before 4 months of age, ultrasound should be utilized to investigate the presence of reno-genitourinary or spinal malformations. Magnetic resonance imaging is the preferred imaging modality in children older than 4 months.⁷ Management of PELVIS syndrome requires a multidisciplinary approach and early recognition of the full extent of congenital malformations. Pediatric dermatologists, urologists, endocrinologists, and neonatologists have a role in its diagnosis and treatment.

The Diagnosis: PELVIS Syndrome

Infantile hemangiomas (IHs) are present in up to 10% of infants by 1 year of age and are most commonly located on the face and upper extremities. Less than 10% of IHs develop in the perineum.¹ Perineal IHs are benign tumors of the vascular endothelium that present as plaques and commonly are accompanied by painful ulcerations. Ulceration is more common in the diaper area secondary to irritation from urine, stool, and friction.² Although most IHs are benign isolated findings, facial IHs have been associated with several syndromes including Sturge-Weber and PHACE (posterior fossa brain malformations, hemangiomas, arterial anomalies, cardiac anomalies and coarctation of the aorta, and eye and endocrine abnormalities) syndromes.³ Researchers also have identified an association between lumbosacral IHs and spinal dysraphism (tethered spinal cord).⁴

A smaller number of studies have investigated congenital anomalies related to perineal IH,^1,5 specifically PELVIS syndrome. The acronym PELVIS has been used to describe a syndrome of congenital malformations including perineal hemangioma, external genital malformations, lipomyelomeningocele, vesicorenal abnormalities, imperforate anus, and skin tag.¹ An alternative description of similar findings is LUMBAR (lower body hemangioma and other cutaneous defects; urogenital anomalies, ulceration; myelopathy; bony deformities; anorectal malformations, arterial anomalies; and renal anomalies).⁵ Researchers have suggested that both of these acronyms describe the same syndrome, and it is common for the syndrome to be incomplete.⁶ One study (N=11) found that perineal hemangiomas are most commonly associated with anal malformations (8 patients), followed by urinary tract abnormalities (7 patients) and malformation of the external genitalia (7 patients). A skin tag was present in 5 patients.¹ The pathogenesis of PELVIS syndrome is unknown.

When an infant presents with a perineal hemangioma and physical examination suggests PELVIS syndrome, imaging should be performed to evaluate for other anomalies. Before 4 months of age, ultrasound should be utilized to investigate the presence of reno-genitourinary or spinal malformations. Magnetic resonance imaging is the preferred imaging modality in children older than 4 months.⁷ Management of PELVIS syndrome requires a multidisciplinary approach and early recognition of the full extent of congenital malformations. Pediatric dermatologists, urologists, endocrinologists, and neonatologists have a role in its diagnosis and treatment.

The Diagnosis: PELVIS Syndrome

Infantile hemangiomas (IHs) are present in up to 10% of infants by 1 year of age and are most commonly located on the face and upper extremities. Less than 10% of IHs develop in the perineum.¹ Perineal IHs are benign tumors of the vascular endothelium that present as plaques and commonly are accompanied by painful ulcerations. Ulceration is more common in the diaper area secondary to irritation from urine, stool, and friction.² Although most IHs are benign isolated findings, facial IHs have been associated with several syndromes including Sturge-Weber and PHACE (posterior fossa brain malformations, hemangiomas, arterial anomalies, cardiac anomalies and coarctation of the aorta, and eye and endocrine abnormalities) syndromes.³ Researchers also have identified an association between lumbosacral IHs and spinal dysraphism (tethered spinal cord).⁴

A smaller number of studies have investigated congenital anomalies related to perineal IH,^1,5 specifically PELVIS syndrome. The acronym PELVIS has been used to describe a syndrome of congenital malformations including perineal hemangioma, external genital malformations, lipomyelomeningocele, vesicorenal abnormalities, imperforate anus, and skin tag.¹ An alternative description of similar findings is LUMBAR (lower body hemangioma and other cutaneous defects; urogenital anomalies, ulceration; myelopathy; bony deformities; anorectal malformations, arterial anomalies; and renal anomalies).⁵ Researchers have suggested that both of these acronyms describe the same syndrome, and it is common for the syndrome to be incomplete.⁶ One study (N=11) found that perineal hemangiomas are most commonly associated with anal malformations (8 patients), followed by urinary tract abnormalities (7 patients) and malformation of the external genitalia (7 patients). A skin tag was present in 5 patients.¹ The pathogenesis of PELVIS syndrome is unknown.

When an infant presents with a perineal hemangioma and physical examination suggests PELVIS syndrome, imaging should be performed to evaluate for other anomalies. Before 4 months of age, ultrasound should be utilized to investigate the presence of reno-genitourinary or spinal malformations. Magnetic resonance imaging is the preferred imaging modality in children older than 4 months.⁷ Management of PELVIS syndrome requires a multidisciplinary approach and early recognition of the full extent of congenital malformations. Pediatric dermatologists, urologists, endocrinologists, and neonatologists have a role in its diagnosis and treatment.

The Diagnosis: Cutaneous Mastocytoma

Physical examination revealed a 58×51-mm hyperpigmented plaque with central pink coloration and scale on the right side of the back as well as a 39×33-mm pink plaque with a hyperpigmented border on the left side of the flank (Figure 1). At follow-up 2 weeks later, the patient's parents reported that blisters formed within both of the plaques. The blisters ruptured a few hours after forming and drained clear fluid with scant blood. Both plaques contained erosions from the ruptured bullae but remained the same size with no surrounding erythema or warmth. A 4-mm punch biopsy was performed of intact skin from the back lesion (Figure 2A). Histologic examination revealed a cellular infiltrate of monotonous bland cells that completely filled the dermis without epidermal involvement, along with occasional intermixed eosinophils. The morphology of these infiltrating cells was compatible with mast cells confirmed by strongly positive Leder staining (Figure 2B).

Mastocytosis encompasses a rare group of disorders characterized by abnormal mast cell accumulation or mast cell mediator release in various tissues. These disorders can be classified as either systemic mastocytosis with mast cell infiltration into bone marrow or other extracutaneous organs, or cutaneous mastocytosis with disease limited to the skin.¹ Mutations involving activation of the c-Kit receptor in stimulating mast cell growth and development have been implicated in both systemic and cutaneous forms of the disease.^2,3

Cutaneous mastocytosis is most often diagnosed in childhood and typically is characterized by spontaneous regression before puberty in a majority of cases.^1,4 Under the World Health Organization classification system, cutaneous mastocytosis can be further subdivided into 3 disorders (listed in order of most to least common): urticaria pigmentosa (also known as maculopapular cutaneous mastocytosis) with typical, plaque, and nodular forms; cutaneous mastocytoma (as seen in this patient); and diffuse cutaneous mastocytosis.⁵ Compared to the widespread distribution of small macules and papules in urticaria pigmentosa, the cutaneous mastocytoma subtype presents with 1 to 6 brown to orange-yellow plaques or nodules measuring more than 1 cm in diameter. Cutaneous mastocytoma typically presents in infancy and is located most commonly on the trunk and extremities, though it may be found on the face or scalp. The plaques of mastocytoma often have well-defined margins, and these lesions may become bullous or demonstrate Darier sign of urtication and erythema on physical stimulation. Patients most commonly experience pruritus from mast cell degranulation and rarely exhibit systemic symptoms of mast cell mediator release; however, generalized flushing, hypotension, headaches, and gastrointestinal symptoms may occur, particularly if the lesion is vigorously rubbed.^6,7 Conditions in the differential include aplasia cutis congenita, connective tissue nevus, epidermal nevus, and epidermolysis bullosa. They should not elicit a blister if rubbed, except for epidermolysis bullosa, which can easily be differentiated based on histology.

The workup for cutaneous mastocytosis in the pediatric population may include a biopsy of lesional skin, though in many cases the characteristic cutaneous manifestations are sufficient to make a diagnosis. Histologically, biopsy results often reveal abundant diffuse dermal infiltration of mast cells, which are characterized by their large pink granular cytoplasm and round dense central nuclei. In pediatric patients, mast cells typically are restricted to the dermis, and there is a low risk for hematologic abnormalities, thereby precluding the need for bone marrow examination in the absence of organomegaly or notable peripheral blood abnormalities such as severe cytopenia.^5,6

Management of cutaneous mastocytosis consists of avoidance of mast cell degranulation triggers and symptomatic treatment of histamine release. Triggers include certain medications (eg, narcotic analgesics, aspirin, nonsteroidal anti-inflammatory drugs, iodinated contrast agents, antibiotics, muscle relaxants), mechanical irritation, insect stings, spicy foods, stress, or extreme temperature changes.⁸ Symptomatic treatment can be achieved through topical corticosteroid or oral antihistamine use. Along with decreasing pruritus, topical corticosteroids also may be helpful in decreasing time to spontaneous resolution and healing.⁷ The patient in this case was treated with desonide ointment 0.05% daily to both lesions as well as mupirocin ointment 2% as needed for erosions. These treatments helped reduce the patient's symptoms, but her lesions persisted over a follow-up period of 4 months.

The Diagnosis: Cutaneous Mastocytoma

Physical examination revealed a 58×51-mm hyperpigmented plaque with central pink coloration and scale on the right side of the back as well as a 39×33-mm pink plaque with a hyperpigmented border on the left side of the flank (Figure 1). At follow-up 2 weeks later, the patient's parents reported that blisters formed within both of the plaques. The blisters ruptured a few hours after forming and drained clear fluid with scant blood. Both plaques contained erosions from the ruptured bullae but remained the same size with no surrounding erythema or warmth. A 4-mm punch biopsy was performed of intact skin from the back lesion (Figure 2A). Histologic examination revealed a cellular infiltrate of monotonous bland cells that completely filled the dermis without epidermal involvement, along with occasional intermixed eosinophils. The morphology of these infiltrating cells was compatible with mast cells confirmed by strongly positive Leder staining (Figure 2B).

Mastocytosis encompasses a rare group of disorders characterized by abnormal mast cell accumulation or mast cell mediator release in various tissues. These disorders can be classified as either systemic mastocytosis with mast cell infiltration into bone marrow or other extracutaneous organs, or cutaneous mastocytosis with disease limited to the skin.¹ Mutations involving activation of the c-Kit receptor in stimulating mast cell growth and development have been implicated in both systemic and cutaneous forms of the disease.^2,3

Cutaneous mastocytosis is most often diagnosed in childhood and typically is characterized by spontaneous regression before puberty in a majority of cases.^1,4 Under the World Health Organization classification system, cutaneous mastocytosis can be further subdivided into 3 disorders (listed in order of most to least common): urticaria pigmentosa (also known as maculopapular cutaneous mastocytosis) with typical, plaque, and nodular forms; cutaneous mastocytoma (as seen in this patient); and diffuse cutaneous mastocytosis.⁵ Compared to the widespread distribution of small macules and papules in urticaria pigmentosa, the cutaneous mastocytoma subtype presents with 1 to 6 brown to orange-yellow plaques or nodules measuring more than 1 cm in diameter. Cutaneous mastocytoma typically presents in infancy and is located most commonly on the trunk and extremities, though it may be found on the face or scalp. The plaques of mastocytoma often have well-defined margins, and these lesions may become bullous or demonstrate Darier sign of urtication and erythema on physical stimulation. Patients most commonly experience pruritus from mast cell degranulation and rarely exhibit systemic symptoms of mast cell mediator release; however, generalized flushing, hypotension, headaches, and gastrointestinal symptoms may occur, particularly if the lesion is vigorously rubbed.^6,7 Conditions in the differential include aplasia cutis congenita, connective tissue nevus, epidermal nevus, and epidermolysis bullosa. They should not elicit a blister if rubbed, except for epidermolysis bullosa, which can easily be differentiated based on histology.

The workup for cutaneous mastocytosis in the pediatric population may include a biopsy of lesional skin, though in many cases the characteristic cutaneous manifestations are sufficient to make a diagnosis. Histologically, biopsy results often reveal abundant diffuse dermal infiltration of mast cells, which are characterized by their large pink granular cytoplasm and round dense central nuclei. In pediatric patients, mast cells typically are restricted to the dermis, and there is a low risk for hematologic abnormalities, thereby precluding the need for bone marrow examination in the absence of organomegaly or notable peripheral blood abnormalities such as severe cytopenia.^5,6

Management of cutaneous mastocytosis consists of avoidance of mast cell degranulation triggers and symptomatic treatment of histamine release. Triggers include certain medications (eg, narcotic analgesics, aspirin, nonsteroidal anti-inflammatory drugs, iodinated contrast agents, antibiotics, muscle relaxants), mechanical irritation, insect stings, spicy foods, stress, or extreme temperature changes.⁸ Symptomatic treatment can be achieved through topical corticosteroid or oral antihistamine use. Along with decreasing pruritus, topical corticosteroids also may be helpful in decreasing time to spontaneous resolution and healing.⁷ The patient in this case was treated with desonide ointment 0.05% daily to both lesions as well as mupirocin ointment 2% as needed for erosions. These treatments helped reduce the patient's symptoms, but her lesions persisted over a follow-up period of 4 months.

The Diagnosis: Cutaneous Mastocytoma

Physical examination revealed a 58×51-mm hyperpigmented plaque with central pink coloration and scale on the right side of the back as well as a 39×33-mm pink plaque with a hyperpigmented border on the left side of the flank (Figure 1). At follow-up 2 weeks later, the patient's parents reported that blisters formed within both of the plaques. The blisters ruptured a few hours after forming and drained clear fluid with scant blood. Both plaques contained erosions from the ruptured bullae but remained the same size with no surrounding erythema or warmth. A 4-mm punch biopsy was performed of intact skin from the back lesion (Figure 2A). Histologic examination revealed a cellular infiltrate of monotonous bland cells that completely filled the dermis without epidermal involvement, along with occasional intermixed eosinophils. The morphology of these infiltrating cells was compatible with mast cells confirmed by strongly positive Leder staining (Figure 2B).

Mastocytosis encompasses a rare group of disorders characterized by abnormal mast cell accumulation or mast cell mediator release in various tissues. These disorders can be classified as either systemic mastocytosis with mast cell infiltration into bone marrow or other extracutaneous organs, or cutaneous mastocytosis with disease limited to the skin.¹ Mutations involving activation of the c-Kit receptor in stimulating mast cell growth and development have been implicated in both systemic and cutaneous forms of the disease.^2,3

Cutaneous mastocytosis is most often diagnosed in childhood and typically is characterized by spontaneous regression before puberty in a majority of cases.^1,4 Under the World Health Organization classification system, cutaneous mastocytosis can be further subdivided into 3 disorders (listed in order of most to least common): urticaria pigmentosa (also known as maculopapular cutaneous mastocytosis) with typical, plaque, and nodular forms; cutaneous mastocytoma (as seen in this patient); and diffuse cutaneous mastocytosis.⁵ Compared to the widespread distribution of small macules and papules in urticaria pigmentosa, the cutaneous mastocytoma subtype presents with 1 to 6 brown to orange-yellow plaques or nodules measuring more than 1 cm in diameter. Cutaneous mastocytoma typically presents in infancy and is located most commonly on the trunk and extremities, though it may be found on the face or scalp. The plaques of mastocytoma often have well-defined margins, and these lesions may become bullous or demonstrate Darier sign of urtication and erythema on physical stimulation. Patients most commonly experience pruritus from mast cell degranulation and rarely exhibit systemic symptoms of mast cell mediator release; however, generalized flushing, hypotension, headaches, and gastrointestinal symptoms may occur, particularly if the lesion is vigorously rubbed.^6,7 Conditions in the differential include aplasia cutis congenita, connective tissue nevus, epidermal nevus, and epidermolysis bullosa. They should not elicit a blister if rubbed, except for epidermolysis bullosa, which can easily be differentiated based on histology.

The workup for cutaneous mastocytosis in the pediatric population may include a biopsy of lesional skin, though in many cases the characteristic cutaneous manifestations are sufficient to make a diagnosis. Histologically, biopsy results often reveal abundant diffuse dermal infiltration of mast cells, which are characterized by their large pink granular cytoplasm and round dense central nuclei. In pediatric patients, mast cells typically are restricted to the dermis, and there is a low risk for hematologic abnormalities, thereby precluding the need for bone marrow examination in the absence of organomegaly or notable peripheral blood abnormalities such as severe cytopenia.^5,6

Management of cutaneous mastocytosis consists of avoidance of mast cell degranulation triggers and symptomatic treatment of histamine release. Triggers include certain medications (eg, narcotic analgesics, aspirin, nonsteroidal anti-inflammatory drugs, iodinated contrast agents, antibiotics, muscle relaxants), mechanical irritation, insect stings, spicy foods, stress, or extreme temperature changes.⁸ Symptomatic treatment can be achieved through topical corticosteroid or oral antihistamine use. Along with decreasing pruritus, topical corticosteroids also may be helpful in decreasing time to spontaneous resolution and healing.⁷ The patient in this case was treated with desonide ointment 0.05% daily to both lesions as well as mupirocin ointment 2% as needed for erosions. These treatments helped reduce the patient's symptoms, but her lesions persisted over a follow-up period of 4 months.

The Diagnosis: Erythema Dyschromicum Perstans

Erythema dyschromicum perstans (EDP), also referred to as ashy dermatosis, was first described by Ramirez¹ in 1957 who labeled the patients los cenicientos (the ashen ones). It preferentially affects women in the second decade of life; however, patients of all ages can be affected, with reported cases occurring in children as young as 2 years of age.² Most patients have Fitzpatrick skin type IV, mainly Amerindian, Hispanic South Asian, and Southwest Asian; however, there are cases reported worldwide.³ A genetic predisposition is proposed, as major histocompatibility complex genes associated with HLA-DR4⁎0407 are frequent in Mexican patients with ashy dermatosis and in the Amerindian population.⁴

The etiology of EDP is unknown. Various contributing factors have been reported including alimentary, occupational, and climatic factors,^5,6 yet none have been conclusively demonstrated. High expression of CD36 (thrombospondin receptor not found in normal skin) in spinous and granular layers, CD94 (cytotoxic cell marker) in the basal cell layer and in the inflammatory dermal infiltrate,⁷ and focal keratinocytic expression of intercellular adhesion molecule I (CD54) in the active lesions of EDP, as well as the absence of these findings in normal skin, suggests an immunologic role in the development of the disease.⁸

Erythema dyschromicum perstans presents clinically with blue-gray hyperpigmented macules varying in size and shape and developing symmetrically in both sun-exposed and sun-protected areas of the face, neck, trunk, arms, and sometimes the dorsal hands (Figures 1 and 2). Notable sparing of the palms, soles, scalp, and mucous membranes occurs.

Occasionally, in the early active stage of the disease, elevated erythematous borders are noted surrounding the hyperpigmented macules. Eventually a hypopigmented halo develops after a prolonged duration of disease.⁹ The eruption typically is chronic and asymptomatic, though some cases may be pruritic.¹⁰

Histopathologically, the early lesions of EDP with an erythematous active border reveal lichenoid dermatitis with basal vacuolar change and occasional Civatte bodies. A mild to moderate perivascular lymphohistiocytic infiltrate admixed with melanophages can be seen in the papillary dermis (Figure 3). In older lesions, the inflammatory infiltrate is sparse, and pigment incontinence consistent with postinflammatory pigmentation is prominent, though melanophages extending deep into the reticular dermis may aid in distinguishing EDP from other causes of postinflammatory pigment alteration.^7,11

Erythema dyschromicum perstans and lichen planus pigmentosus (LPP) may be indistinguishable histopathologically and may both be variants of lichen planus actinicus. Lichen planus pigmentosus often differs from EDP in that it presents with brown-black macules and patches often on the face and flexural areas. A subset of cases of LPP also may have mucous membrane involvement. The erythematous border that characterizes the active lesion of EDP is characteristically absent in LPP. In addition, pruritus often is reported with LPP. Direct immunofluorescence is not a beneficial tool in distinguishing the entities.¹²

Other differential diagnoses of predominantly facial hyperpigmentation include a lichenoid drug eruption; drug-induced hyperpigmentation (deposition disorder); postinflammatory hyperpigmentation following atopic dermatitis; contact dermatitis or photosensitivity reaction; early pinta; and cutaneous findings of systemic diseases manifesting with diffuse hyperpigmentation such as lupus erythematosus, dermatomyositis, hemochromatosis, and Addison disease. A detailed history including medication use, thorough clinical examination, and careful histopathologic evaluation will help distinguish these conditions.

Chrysiasis is a rare bluish to slate gray discoloration of the skin that predominantly occurs in sun-exposed areas. It is caused by chronic use of gold salts, which have been used to treat rheumatoid arthritis. UV light may contribute to induce the uptake of gold and subsequently stimulate tyrosinase activity.¹³ Histologic features of chrysiasis include dermal and perivascular gold deposition within the macrophages and endothelial cells as well as extracellular granules. It demonstrates an orange-red birefringence on fluorescent microscopy.^14,15

Minocycline-induced hyperpigmentation is a well-recognized side effect of this drug. It is dose dependent and appears as a blue-black pigmentation that most frequently affects the shins, ankles, and arms.¹⁶ Three distinct types were documented: abnormal discoloration of the skin that has been linked to deposition of pigmented metabolites of minocycline producing blue-black pigmentation at the site of scarring or prior inflammation (type 1); blue-gray pigmentation affecting normal skin, mainly the legs (type 2); and elevated levels of melanin on the sun-exposed areas producing dirty skin syndrome (type 3).^17,18

Topical and systemic corticosteroids, UV light therapy, oral dapsone, griseofulvin, retinoids, and clofazimine are reported as treatment options for ashy dermatosis, though results typically are disappointing.⁷

The Diagnosis: Erythema Dyschromicum Perstans

Erythema dyschromicum perstans (EDP), also referred to as ashy dermatosis, was first described by Ramirez¹ in 1957 who labeled the patients los cenicientos (the ashen ones). It preferentially affects women in the second decade of life; however, patients of all ages can be affected, with reported cases occurring in children as young as 2 years of age.² Most patients have Fitzpatrick skin type IV, mainly Amerindian, Hispanic South Asian, and Southwest Asian; however, there are cases reported worldwide.³ A genetic predisposition is proposed, as major histocompatibility complex genes associated with HLA-DR4⁎0407 are frequent in Mexican patients with ashy dermatosis and in the Amerindian population.⁴

The etiology of EDP is unknown. Various contributing factors have been reported including alimentary, occupational, and climatic factors,^5,6 yet none have been conclusively demonstrated. High expression of CD36 (thrombospondin receptor not found in normal skin) in spinous and granular layers, CD94 (cytotoxic cell marker) in the basal cell layer and in the inflammatory dermal infiltrate,⁷ and focal keratinocytic expression of intercellular adhesion molecule I (CD54) in the active lesions of EDP, as well as the absence of these findings in normal skin, suggests an immunologic role in the development of the disease.⁸

Erythema dyschromicum perstans presents clinically with blue-gray hyperpigmented macules varying in size and shape and developing symmetrically in both sun-exposed and sun-protected areas of the face, neck, trunk, arms, and sometimes the dorsal hands (Figures 1 and 2). Notable sparing of the palms, soles, scalp, and mucous membranes occurs.

Occasionally, in the early active stage of the disease, elevated erythematous borders are noted surrounding the hyperpigmented macules. Eventually a hypopigmented halo develops after a prolonged duration of disease.⁹ The eruption typically is chronic and asymptomatic, though some cases may be pruritic.¹⁰

Histopathologically, the early lesions of EDP with an erythematous active border reveal lichenoid dermatitis with basal vacuolar change and occasional Civatte bodies. A mild to moderate perivascular lymphohistiocytic infiltrate admixed with melanophages can be seen in the papillary dermis (Figure 3). In older lesions, the inflammatory infiltrate is sparse, and pigment incontinence consistent with postinflammatory pigmentation is prominent, though melanophages extending deep into the reticular dermis may aid in distinguishing EDP from other causes of postinflammatory pigment alteration.^7,11

Erythema dyschromicum perstans and lichen planus pigmentosus (LPP) may be indistinguishable histopathologically and may both be variants of lichen planus actinicus. Lichen planus pigmentosus often differs from EDP in that it presents with brown-black macules and patches often on the face and flexural areas. A subset of cases of LPP also may have mucous membrane involvement. The erythematous border that characterizes the active lesion of EDP is characteristically absent in LPP. In addition, pruritus often is reported with LPP. Direct immunofluorescence is not a beneficial tool in distinguishing the entities.¹²

Other differential diagnoses of predominantly facial hyperpigmentation include a lichenoid drug eruption; drug-induced hyperpigmentation (deposition disorder); postinflammatory hyperpigmentation following atopic dermatitis; contact dermatitis or photosensitivity reaction; early pinta; and cutaneous findings of systemic diseases manifesting with diffuse hyperpigmentation such as lupus erythematosus, dermatomyositis, hemochromatosis, and Addison disease. A detailed history including medication use, thorough clinical examination, and careful histopathologic evaluation will help distinguish these conditions.

Chrysiasis is a rare bluish to slate gray discoloration of the skin that predominantly occurs in sun-exposed areas. It is caused by chronic use of gold salts, which have been used to treat rheumatoid arthritis. UV light may contribute to induce the uptake of gold and subsequently stimulate tyrosinase activity.¹³ Histologic features of chrysiasis include dermal and perivascular gold deposition within the macrophages and endothelial cells as well as extracellular granules. It demonstrates an orange-red birefringence on fluorescent microscopy.^14,15

Minocycline-induced hyperpigmentation is a well-recognized side effect of this drug. It is dose dependent and appears as a blue-black pigmentation that most frequently affects the shins, ankles, and arms.¹⁶ Three distinct types were documented: abnormal discoloration of the skin that has been linked to deposition of pigmented metabolites of minocycline producing blue-black pigmentation at the site of scarring or prior inflammation (type 1); blue-gray pigmentation affecting normal skin, mainly the legs (type 2); and elevated levels of melanin on the sun-exposed areas producing dirty skin syndrome (type 3).^17,18

Topical and systemic corticosteroids, UV light therapy, oral dapsone, griseofulvin, retinoids, and clofazimine are reported as treatment options for ashy dermatosis, though results typically are disappointing.⁷

The Diagnosis: Erythema Dyschromicum Perstans

Erythema dyschromicum perstans (EDP), also referred to as ashy dermatosis, was first described by Ramirez¹ in 1957 who labeled the patients los cenicientos (the ashen ones). It preferentially affects women in the second decade of life; however, patients of all ages can be affected, with reported cases occurring in children as young as 2 years of age.² Most patients have Fitzpatrick skin type IV, mainly Amerindian, Hispanic South Asian, and Southwest Asian; however, there are cases reported worldwide.³ A genetic predisposition is proposed, as major histocompatibility complex genes associated with HLA-DR4⁎0407 are frequent in Mexican patients with ashy dermatosis and in the Amerindian population.⁴

The etiology of EDP is unknown. Various contributing factors have been reported including alimentary, occupational, and climatic factors,^5,6 yet none have been conclusively demonstrated. High expression of CD36 (thrombospondin receptor not found in normal skin) in spinous and granular layers, CD94 (cytotoxic cell marker) in the basal cell layer and in the inflammatory dermal infiltrate,⁷ and focal keratinocytic expression of intercellular adhesion molecule I (CD54) in the active lesions of EDP, as well as the absence of these findings in normal skin, suggests an immunologic role in the development of the disease.⁸

Erythema dyschromicum perstans presents clinically with blue-gray hyperpigmented macules varying in size and shape and developing symmetrically in both sun-exposed and sun-protected areas of the face, neck, trunk, arms, and sometimes the dorsal hands (Figures 1 and 2). Notable sparing of the palms, soles, scalp, and mucous membranes occurs.

Occasionally, in the early active stage of the disease, elevated erythematous borders are noted surrounding the hyperpigmented macules. Eventually a hypopigmented halo develops after a prolonged duration of disease.⁹ The eruption typically is chronic and asymptomatic, though some cases may be pruritic.¹⁰

Histopathologically, the early lesions of EDP with an erythematous active border reveal lichenoid dermatitis with basal vacuolar change and occasional Civatte bodies. A mild to moderate perivascular lymphohistiocytic infiltrate admixed with melanophages can be seen in the papillary dermis (Figure 3). In older lesions, the inflammatory infiltrate is sparse, and pigment incontinence consistent with postinflammatory pigmentation is prominent, though melanophages extending deep into the reticular dermis may aid in distinguishing EDP from other causes of postinflammatory pigment alteration.^7,11

Erythema dyschromicum perstans and lichen planus pigmentosus (LPP) may be indistinguishable histopathologically and may both be variants of lichen planus actinicus. Lichen planus pigmentosus often differs from EDP in that it presents with brown-black macules and patches often on the face and flexural areas. A subset of cases of LPP also may have mucous membrane involvement. The erythematous border that characterizes the active lesion of EDP is characteristically absent in LPP. In addition, pruritus often is reported with LPP. Direct immunofluorescence is not a beneficial tool in distinguishing the entities.¹²

Other differential diagnoses of predominantly facial hyperpigmentation include a lichenoid drug eruption; drug-induced hyperpigmentation (deposition disorder); postinflammatory hyperpigmentation following atopic dermatitis; contact dermatitis or photosensitivity reaction; early pinta; and cutaneous findings of systemic diseases manifesting with diffuse hyperpigmentation such as lupus erythematosus, dermatomyositis, hemochromatosis, and Addison disease. A detailed history including medication use, thorough clinical examination, and careful histopathologic evaluation will help distinguish these conditions.

Chrysiasis is a rare bluish to slate gray discoloration of the skin that predominantly occurs in sun-exposed areas. It is caused by chronic use of gold salts, which have been used to treat rheumatoid arthritis. UV light may contribute to induce the uptake of gold and subsequently stimulate tyrosinase activity.¹³ Histologic features of chrysiasis include dermal and perivascular gold deposition within the macrophages and endothelial cells as well as extracellular granules. It demonstrates an orange-red birefringence on fluorescent microscopy.^14,15

Minocycline-induced hyperpigmentation is a well-recognized side effect of this drug. It is dose dependent and appears as a blue-black pigmentation that most frequently affects the shins, ankles, and arms.¹⁶ Three distinct types were documented: abnormal discoloration of the skin that has been linked to deposition of pigmented metabolites of minocycline producing blue-black pigmentation at the site of scarring or prior inflammation (type 1); blue-gray pigmentation affecting normal skin, mainly the legs (type 2); and elevated levels of melanin on the sun-exposed areas producing dirty skin syndrome (type 3).^17,18

Topical and systemic corticosteroids, UV light therapy, oral dapsone, griseofulvin, retinoids, and clofazimine are reported as treatment options for ashy dermatosis, though results typically are disappointing.⁷

The Diagnosis: Hypertrophic Lupus Erythematosus

Physical examination at initial presentation revealed well-demarcated, 2- to 3-cm plaques with scale distributed most extensively on the elbows and shins with lesser involvement of the chest and abdomen. After treatment with topical steroids, adalimumab, methotrexate, and narrowband UVB phototherapy, new annular, erythematous, and edematous lesions began to appear on the chest and abdomen (Figure 1). These new lesions appeared less hyperkeratotic than the older ones.

Biopsy of a hyperkeratotic lesion from the patient's arm revealed marked hyperkeratosis, parakeratosis, epidermal hyperplasia, focal vacuolar change, solar elastosis, and transepidermal elastotic elimination (Figure 2A). A second biopsy performed on a newer chest lesion revealed interface changes, degeneration of the basal layer, follicular plugging, and dermal mucin (Figure 2B). Serology revealed an antinuclear antibody (ANA) titer of 1:1280 (reference range, <1:40 dilution) and hemoglobin of 11.5 g/dL (reference range, 14.0-17.5 g/dL). On the basis of clinical, histologic, and serologic findings, hypertrophic lupus erythematosus (LE) was diagnosed. The patient was treated with oral prednisone, which resulted in rapid improvement.

Hypertrophic LE is a rare subset of chronic cutaneous lupus first described by Behcet¹ in 1942. Lesions are identified as verrucous keratotic plaques with a characteristic erythematous indurated border.² Patients predominantly are middle-aged women with lesions distributed on sun-exposed areas. Most often, hypertrophic LE is seen in association with the classic lesions of discoid LE; however, patients may present exclusively with the cutaneous manifestations of hypertrophic LE. More rarely, as seen in this case, hypertrophic LE may present in conjunction with systemic features.³ The diagnosis of systemic LE requires 4 of the following criteria be fulfilled: malar rash; discoid rash; photosensitivity; oral ulcers; arthritis; cardiopulmonary serositis; renal involvement; positive ANA titer; and neurologic, hematologic, or immunologic disorders.⁴ Our patient qualified for discoid rash, photosensitivity, cardiopulmonary involvement with mitral valve defects and pulmonary pleuritis, hematologic disorder (anemia), and a positive ANA titer. Furthermore, in patients with only cutaneous discoid LE, serology generally reveals negative or low-titer ANA and negative anti-Ro antibodies.⁵

Hypertrophic LE is characterized histologically by irregular epidermal hyperplasia in association with features of classic cutaneous LE. Distinctive features of cutaneous LE include interface changes, follicular plugging, dermal mucin, and angiocentric lymphocytic inflammation.⁶ Notably, additional biopsies of the less hyperkeratotic lesions on our patient's chest and abdomen were performed, which revealed classic cutaneous LE features (Figure 2B).

Hypertrophic LE has 2 histological variants: lichen planus-like and keratoacanthoma (KA)-like patterns. Most cases are described as lichen planus-like, with a dense bandlike infiltrate in association with irregular epidermal hyperplasia, vacuolar interface changes, and reactive squamous atypia.⁵ In contrast, the less common KA-like lesions consist of a keratinous center with vigorous squamous epithelial proliferation.⁶

Clinically, hypertrophic LE may resemble hypertrophic psoriasis, lichen planus, KA, or squamous cell carcinoma (SCC). Due to the presence of pseudocarcinomatous hyperplasia, the histopathologic differential includes hypertrophic lichen planus, SCC, KA, and deep fungal infections. However, these other diseases lack the classic features of cutaneous LE, which include interface changes, follicular plugging, dermal mucin, and perivascular lymphocytic inflammation. Additionally, transepidermal elastotic elimination (Figure 2A) helps distinguish hypertrophic LE from other diagnoses.⁷ One of the most important tasks is distinguishing hypertrophic LE from SCC. Hypertrophic LE does not typically display eosinophil infiltrates, which differentiates it from SCC and KA. Additionally, studies report that CD123 positivity can be useful.⁶ Positive plasmacytoid dendritic cells are abundant at the dermoepidermal junction in hypertrophic LE, while only single or rare clusters of CD123⁺ cells are seen in SCC.⁸ Also, SCC has been found to arise in long-standing cutaneous LE lesions including both discoid and hypertrophic LE. Therefore, clinical and sometimes histological follow-up is required.

Hypertrophic LE often is challenging to treat and frequently is resistant to antimalarial drugs. The primary goals of treatment involve reducing inflammatory infiltrate and minimizing hyperkeratinization. Topical corticosteroids and calcineurin inhibitors often are inadequate as monotherapy due to reduced penetrance through the thick lesions; however, intralesional corticosteroids may be beneficial in patients with localized disease.⁹ Unfortunately, topical or intralesional treatments are impractical in patients with extensive lesions, as seen in our patient, in which case systemic corticosteroids can be beneficial.

Topical retinoids also have been found to be highly effective.¹⁰ Specifically, retinoids such as acitretin and isotretinoin, in some cases combined with antimalarial drugs, are effective in reducing the keratinization of these lesions. Successful treatment also has been reported with ustekinumab, thalidomide, mycophenolate mofetil, and pulsed dye laser.¹¹ As in other types of cutaneous LE, hyperkeratotic LE is photosensitive; avoidance of prolonged sun exposure should be advised.⁸

The Diagnosis: Hypertrophic Lupus Erythematosus

Physical examination at initial presentation revealed well-demarcated, 2- to 3-cm plaques with scale distributed most extensively on the elbows and shins with lesser involvement of the chest and abdomen. After treatment with topical steroids, adalimumab, methotrexate, and narrowband UVB phototherapy, new annular, erythematous, and edematous lesions began to appear on the chest and abdomen (Figure 1). These new lesions appeared less hyperkeratotic than the older ones.

Biopsy of a hyperkeratotic lesion from the patient's arm revealed marked hyperkeratosis, parakeratosis, epidermal hyperplasia, focal vacuolar change, solar elastosis, and transepidermal elastotic elimination (Figure 2A). A second biopsy performed on a newer chest lesion revealed interface changes, degeneration of the basal layer, follicular plugging, and dermal mucin (Figure 2B). Serology revealed an antinuclear antibody (ANA) titer of 1:1280 (reference range, <1:40 dilution) and hemoglobin of 11.5 g/dL (reference range, 14.0-17.5 g/dL). On the basis of clinical, histologic, and serologic findings, hypertrophic lupus erythematosus (LE) was diagnosed. The patient was treated with oral prednisone, which resulted in rapid improvement.

Hypertrophic LE is a rare subset of chronic cutaneous lupus first described by Behcet¹ in 1942. Lesions are identified as verrucous keratotic plaques with a characteristic erythematous indurated border.² Patients predominantly are middle-aged women with lesions distributed on sun-exposed areas. Most often, hypertrophic LE is seen in association with the classic lesions of discoid LE; however, patients may present exclusively with the cutaneous manifestations of hypertrophic LE. More rarely, as seen in this case, hypertrophic LE may present in conjunction with systemic features.³ The diagnosis of systemic LE requires 4 of the following criteria be fulfilled: malar rash; discoid rash; photosensitivity; oral ulcers; arthritis; cardiopulmonary serositis; renal involvement; positive ANA titer; and neurologic, hematologic, or immunologic disorders.⁴ Our patient qualified for discoid rash, photosensitivity, cardiopulmonary involvement with mitral valve defects and pulmonary pleuritis, hematologic disorder (anemia), and a positive ANA titer. Furthermore, in patients with only cutaneous discoid LE, serology generally reveals negative or low-titer ANA and negative anti-Ro antibodies.⁵

Hypertrophic LE is characterized histologically by irregular epidermal hyperplasia in association with features of classic cutaneous LE. Distinctive features of cutaneous LE include interface changes, follicular plugging, dermal mucin, and angiocentric lymphocytic inflammation.⁶ Notably, additional biopsies of the less hyperkeratotic lesions on our patient's chest and abdomen were performed, which revealed classic cutaneous LE features (Figure 2B).

Hypertrophic LE has 2 histological variants: lichen planus-like and keratoacanthoma (KA)-like patterns. Most cases are described as lichen planus-like, with a dense bandlike infiltrate in association with irregular epidermal hyperplasia, vacuolar interface changes, and reactive squamous atypia.⁵ In contrast, the less common KA-like lesions consist of a keratinous center with vigorous squamous epithelial proliferation.⁶

Clinically, hypertrophic LE may resemble hypertrophic psoriasis, lichen planus, KA, or squamous cell carcinoma (SCC). Due to the presence of pseudocarcinomatous hyperplasia, the histopathologic differential includes hypertrophic lichen planus, SCC, KA, and deep fungal infections. However, these other diseases lack the classic features of cutaneous LE, which include interface changes, follicular plugging, dermal mucin, and perivascular lymphocytic inflammation. Additionally, transepidermal elastotic elimination (Figure 2A) helps distinguish hypertrophic LE from other diagnoses.⁷ One of the most important tasks is distinguishing hypertrophic LE from SCC. Hypertrophic LE does not typically display eosinophil infiltrates, which differentiates it from SCC and KA. Additionally, studies report that CD123 positivity can be useful.⁶ Positive plasmacytoid dendritic cells are abundant at the dermoepidermal junction in hypertrophic LE, while only single or rare clusters of CD123⁺ cells are seen in SCC.⁸ Also, SCC has been found to arise in long-standing cutaneous LE lesions including both discoid and hypertrophic LE. Therefore, clinical and sometimes histological follow-up is required.

Hypertrophic LE often is challenging to treat and frequently is resistant to antimalarial drugs. The primary goals of treatment involve reducing inflammatory infiltrate and minimizing hyperkeratinization. Topical corticosteroids and calcineurin inhibitors often are inadequate as monotherapy due to reduced penetrance through the thick lesions; however, intralesional corticosteroids may be beneficial in patients with localized disease.⁹ Unfortunately, topical or intralesional treatments are impractical in patients with extensive lesions, as seen in our patient, in which case systemic corticosteroids can be beneficial.

Topical retinoids also have been found to be highly effective.¹⁰ Specifically, retinoids such as acitretin and isotretinoin, in some cases combined with antimalarial drugs, are effective in reducing the keratinization of these lesions. Successful treatment also has been reported with ustekinumab, thalidomide, mycophenolate mofetil, and pulsed dye laser.¹¹ As in other types of cutaneous LE, hyperkeratotic LE is photosensitive; avoidance of prolonged sun exposure should be advised.⁸

The Diagnosis: Hypertrophic Lupus Erythematosus

Physical examination at initial presentation revealed well-demarcated, 2- to 3-cm plaques with scale distributed most extensively on the elbows and shins with lesser involvement of the chest and abdomen. After treatment with topical steroids, adalimumab, methotrexate, and narrowband UVB phototherapy, new annular, erythematous, and edematous lesions began to appear on the chest and abdomen (Figure 1). These new lesions appeared less hyperkeratotic than the older ones.

Biopsy of a hyperkeratotic lesion from the patient's arm revealed marked hyperkeratosis, parakeratosis, epidermal hyperplasia, focal vacuolar change, solar elastosis, and transepidermal elastotic elimination (Figure 2A). A second biopsy performed on a newer chest lesion revealed interface changes, degeneration of the basal layer, follicular plugging, and dermal mucin (Figure 2B). Serology revealed an antinuclear antibody (ANA) titer of 1:1280 (reference range, <1:40 dilution) and hemoglobin of 11.5 g/dL (reference range, 14.0-17.5 g/dL). On the basis of clinical, histologic, and serologic findings, hypertrophic lupus erythematosus (LE) was diagnosed. The patient was treated with oral prednisone, which resulted in rapid improvement.

Hypertrophic LE is a rare subset of chronic cutaneous lupus first described by Behcet¹ in 1942. Lesions are identified as verrucous keratotic plaques with a characteristic erythematous indurated border.² Patients predominantly are middle-aged women with lesions distributed on sun-exposed areas. Most often, hypertrophic LE is seen in association with the classic lesions of discoid LE; however, patients may present exclusively with the cutaneous manifestations of hypertrophic LE. More rarely, as seen in this case, hypertrophic LE may present in conjunction with systemic features.³ The diagnosis of systemic LE requires 4 of the following criteria be fulfilled: malar rash; discoid rash; photosensitivity; oral ulcers; arthritis; cardiopulmonary serositis; renal involvement; positive ANA titer; and neurologic, hematologic, or immunologic disorders.⁴ Our patient qualified for discoid rash, photosensitivity, cardiopulmonary involvement with mitral valve defects and pulmonary pleuritis, hematologic disorder (anemia), and a positive ANA titer. Furthermore, in patients with only cutaneous discoid LE, serology generally reveals negative or low-titer ANA and negative anti-Ro antibodies.⁵

Hypertrophic LE is characterized histologically by irregular epidermal hyperplasia in association with features of classic cutaneous LE. Distinctive features of cutaneous LE include interface changes, follicular plugging, dermal mucin, and angiocentric lymphocytic inflammation.⁶ Notably, additional biopsies of the less hyperkeratotic lesions on our patient's chest and abdomen were performed, which revealed classic cutaneous LE features (Figure 2B).

Hypertrophic LE has 2 histological variants: lichen planus-like and keratoacanthoma (KA)-like patterns. Most cases are described as lichen planus-like, with a dense bandlike infiltrate in association with irregular epidermal hyperplasia, vacuolar interface changes, and reactive squamous atypia.⁵ In contrast, the less common KA-like lesions consist of a keratinous center with vigorous squamous epithelial proliferation.⁶

Clinically, hypertrophic LE may resemble hypertrophic psoriasis, lichen planus, KA, or squamous cell carcinoma (SCC). Due to the presence of pseudocarcinomatous hyperplasia, the histopathologic differential includes hypertrophic lichen planus, SCC, KA, and deep fungal infections. However, these other diseases lack the classic features of cutaneous LE, which include interface changes, follicular plugging, dermal mucin, and perivascular lymphocytic inflammation. Additionally, transepidermal elastotic elimination (Figure 2A) helps distinguish hypertrophic LE from other diagnoses.⁷ One of the most important tasks is distinguishing hypertrophic LE from SCC. Hypertrophic LE does not typically display eosinophil infiltrates, which differentiates it from SCC and KA. Additionally, studies report that CD123 positivity can be useful.⁶ Positive plasmacytoid dendritic cells are abundant at the dermoepidermal junction in hypertrophic LE, while only single or rare clusters of CD123⁺ cells are seen in SCC.⁸ Also, SCC has been found to arise in long-standing cutaneous LE lesions including both discoid and hypertrophic LE. Therefore, clinical and sometimes histological follow-up is required.

Hypertrophic LE often is challenging to treat and frequently is resistant to antimalarial drugs. The primary goals of treatment involve reducing inflammatory infiltrate and minimizing hyperkeratinization. Topical corticosteroids and calcineurin inhibitors often are inadequate as monotherapy due to reduced penetrance through the thick lesions; however, intralesional corticosteroids may be beneficial in patients with localized disease.⁹ Unfortunately, topical or intralesional treatments are impractical in patients with extensive lesions, as seen in our patient, in which case systemic corticosteroids can be beneficial.

Topical retinoids also have been found to be highly effective.¹⁰ Specifically, retinoids such as acitretin and isotretinoin, in some cases combined with antimalarial drugs, are effective in reducing the keratinization of these lesions. Successful treatment also has been reported with ustekinumab, thalidomide, mycophenolate mofetil, and pulsed dye laser.¹¹ As in other types of cutaneous LE, hyperkeratotic LE is photosensitive; avoidance of prolonged sun exposure should be advised.⁸