Candrice R. Heath, MD

The Comparison

A Plantar hyperpigmentation (benign ethnic melanosis) on the sole of the foot in a 62-year-old man of African descent with deeply pigmented skin. Dermoscopy showed a parallel ridge pattern even though the hyperpigmentation was benign (inset).

B Melanoma in situ with multicomponent hyperpigmentation on the sole of the foot in a 65-year-old Hispanic woman. Dermoscopy revealed a parallel ridge pattern (inset).

bufrish

Plantar hyperpigmentation (also known as plantar melanosis [increased melanin], volar pigmented macules, benign racial melanosis, acral pigmentation, acral ethnic melanosis, or mottled hyperpigmentation of the plantar surface) is a benign finding in many individuals and is especially prevalent in those with darker skin tones. Acral refers to manifestation on the hands and feet, volar on the palms and soles, and plantar on the soles only. Here, we focus on plantar hyperpigmentation. We use the terms ethnic and racial interchangeably.

It is critically important to differentiate benign hyperpigmentation, which is common in patients with skin of color, from melanoma. Although rare, Black patients in the United States experience high morbidity and mortality from acral melanoma, which often is diagnosed late in the disease course.¹

There are many causes of hyperpigmentation on the plantar surfaces, including benign ethnic melanosis, nevi, melanoma, infections such as syphilis and tinea nigra, conditions such as Peutz-Jeghers syndrome and Laugier-Hunziker syndrome, and postinflammatory hyperpigmentation secondary to atopic dermatitis and psoriasis. We focus on the most common causes, ethnic melanosis and nevi, as well as melanoma, which is the deadliest cause.

Epidemiology

In a 1980 study (N=251), Black Americans had a high incidence of plantar hyperpigmentation, with 52% of affected patients having dark brown skin and 31% having light brown skin.²

The epidemiology of melanoma varies by race/ethnicity. Melanoma in Black individuals is relatively rare, with an annual incidence of approximately 1 in 100,000 individuals.³ However, when individuals with skin of color develop melanoma, they are more likely than their White counterparts to have acral melanoma (acral lentiginous melanoma), one of the deadliest types.¹ In a case series of Black patients with melanoma (N=48) from 2 tertiary care centers in Texas, 30 of 40 primary cutaneous melanomas (75%) were located on acral skin.⁴ Overall, 13 patients developed stage IV disease and 12 died due to disease progression. All patients who developed distant metastases or died of melanoma had acral melanoma.⁴ Individuals of Asian descent also have a high incidence of acral melanoma, as shown in research from Japan.^5-9

Key clinical features in individuals with darker skin tones

Dermoscopy is an evidence-based clinical examination method for earlier diagnosis of cutaneous melanoma, including on acral skin.^10,11 Benign nevi on the volar skin as well as the palms and soles tend to have one of these 3 dermoscopic patterns: parallel furrow, lattice, or irregular fibrillar. The pattern that is most predictive of volar melanoma is the parallel ridge pattern (PRP) (Figures A and B [insets]), which showed a high specificity (99.0%) and very high negative predictive value (97.7%) for malignant melanoma in a Japanese population.⁷ The PRP data from this study cannot be applied reliably to Black individuals, especially because benign ethnic melanosis and other benign conditions can demonstrate PRP.¹² Reliance on the PRP as a diagnostic clue could result in unneccessary biopsies in as many as 50% of Black patients with benign plantar hyperpigmentation.² Furthermore, biopsies of the plantar surface can be painful and cause pain while walking.

It has been suggested that PRP seen on dermoscopy in benign hyperpigmentation such as ethnic melanosis and nevi may preserve the acrosyringia (eccrine gland openings on the ridge), whereas PRP in melanoma may obliterate the acrosyringia.¹³ This observation is based on case reports only and needs further study. However, if validated, it could be a useful diagnostic clue.

Worth noting

In a retrospective cohort study of skin cancer in Black individuals (n=165) at a New York City–based cancer center from 2000 to 2020, 68% of patients were diagnosed with melanomas—80% were the acral subtype and 75% displayed a PRP. However, the surrounding uninvolved background skin, which was visible in most cases, also demonstrated a PRP.¹⁴ Because of the high morbidity and mortality rates of acral melanoma, clinicians should biopsy or immediately refer patients with concerning plantar hyperpigmentation to a dermatologist.

Health disparity highlight

The mortality rate for acral melanoma in Black patients is disproportionately high for the following reasons^15,16:

• Patients and health care providers do not expect to see melanoma in Black patients (it truly is rare!), so screening and education on sun protection are limited.
• Benign ethnic melanosis makes it more difficult to distinguish between early acral melanoma and benign skin changes.
• Black patients and other US patient populations with skin of color may be less likely to have health insurance, which contributes to inequities in access to health care. As of 2022, the uninsured rates for nonelderly American Indian and Alaska Native, Hispanic, Native Hawaiian and Other Pacific Islander, Black, and White individuals were 19.1%, 18.0%, 12.7%, 10.0%, and 6.6%, respectively.¹⁷

Multi-institutional registries could improve understanding of acral melanoma in Black patients.⁴ More studies are needed to help differentiate between the dermoscopic finding of PRP in benign ethnic melanosis vs malignant melanoma.

The Comparison

A Plantar hyperpigmentation (benign ethnic melanosis) on the sole of the foot in a 62-year-old man of African descent with deeply pigmented skin. Dermoscopy showed a parallel ridge pattern even though the hyperpigmentation was benign (inset).

B Melanoma in situ with multicomponent hyperpigmentation on the sole of the foot in a 65-year-old Hispanic woman. Dermoscopy revealed a parallel ridge pattern (inset).

bufrish

Plantar hyperpigmentation (also known as plantar melanosis [increased melanin], volar pigmented macules, benign racial melanosis, acral pigmentation, acral ethnic melanosis, or mottled hyperpigmentation of the plantar surface) is a benign finding in many individuals and is especially prevalent in those with darker skin tones. Acral refers to manifestation on the hands and feet, volar on the palms and soles, and plantar on the soles only. Here, we focus on plantar hyperpigmentation. We use the terms ethnic and racial interchangeably.

It is critically important to differentiate benign hyperpigmentation, which is common in patients with skin of color, from melanoma. Although rare, Black patients in the United States experience high morbidity and mortality from acral melanoma, which often is diagnosed late in the disease course.¹

There are many causes of hyperpigmentation on the plantar surfaces, including benign ethnic melanosis, nevi, melanoma, infections such as syphilis and tinea nigra, conditions such as Peutz-Jeghers syndrome and Laugier-Hunziker syndrome, and postinflammatory hyperpigmentation secondary to atopic dermatitis and psoriasis. We focus on the most common causes, ethnic melanosis and nevi, as well as melanoma, which is the deadliest cause.

Epidemiology

In a 1980 study (N=251), Black Americans had a high incidence of plantar hyperpigmentation, with 52% of affected patients having dark brown skin and 31% having light brown skin.²

The epidemiology of melanoma varies by race/ethnicity. Melanoma in Black individuals is relatively rare, with an annual incidence of approximately 1 in 100,000 individuals.³ However, when individuals with skin of color develop melanoma, they are more likely than their White counterparts to have acral melanoma (acral lentiginous melanoma), one of the deadliest types.¹ In a case series of Black patients with melanoma (N=48) from 2 tertiary care centers in Texas, 30 of 40 primary cutaneous melanomas (75%) were located on acral skin.⁴ Overall, 13 patients developed stage IV disease and 12 died due to disease progression. All patients who developed distant metastases or died of melanoma had acral melanoma.⁴ Individuals of Asian descent also have a high incidence of acral melanoma, as shown in research from Japan.^5-9

Key clinical features in individuals with darker skin tones

Dermoscopy is an evidence-based clinical examination method for earlier diagnosis of cutaneous melanoma, including on acral skin.^10,11 Benign nevi on the volar skin as well as the palms and soles tend to have one of these 3 dermoscopic patterns: parallel furrow, lattice, or irregular fibrillar. The pattern that is most predictive of volar melanoma is the parallel ridge pattern (PRP) (Figures A and B [insets]), which showed a high specificity (99.0%) and very high negative predictive value (97.7%) for malignant melanoma in a Japanese population.⁷ The PRP data from this study cannot be applied reliably to Black individuals, especially because benign ethnic melanosis and other benign conditions can demonstrate PRP.¹² Reliance on the PRP as a diagnostic clue could result in unneccessary biopsies in as many as 50% of Black patients with benign plantar hyperpigmentation.² Furthermore, biopsies of the plantar surface can be painful and cause pain while walking.

It has been suggested that PRP seen on dermoscopy in benign hyperpigmentation such as ethnic melanosis and nevi may preserve the acrosyringia (eccrine gland openings on the ridge), whereas PRP in melanoma may obliterate the acrosyringia.¹³ This observation is based on case reports only and needs further study. However, if validated, it could be a useful diagnostic clue.

Worth noting

In a retrospective cohort study of skin cancer in Black individuals (n=165) at a New York City–based cancer center from 2000 to 2020, 68% of patients were diagnosed with melanomas—80% were the acral subtype and 75% displayed a PRP. However, the surrounding uninvolved background skin, which was visible in most cases, also demonstrated a PRP.¹⁴ Because of the high morbidity and mortality rates of acral melanoma, clinicians should biopsy or immediately refer patients with concerning plantar hyperpigmentation to a dermatologist.

Health disparity highlight

The mortality rate for acral melanoma in Black patients is disproportionately high for the following reasons^15,16:

• Patients and health care providers do not expect to see melanoma in Black patients (it truly is rare!), so screening and education on sun protection are limited.
• Benign ethnic melanosis makes it more difficult to distinguish between early acral melanoma and benign skin changes.
• Black patients and other US patient populations with skin of color may be less likely to have health insurance, which contributes to inequities in access to health care. As of 2022, the uninsured rates for nonelderly American Indian and Alaska Native, Hispanic, Native Hawaiian and Other Pacific Islander, Black, and White individuals were 19.1%, 18.0%, 12.7%, 10.0%, and 6.6%, respectively.¹⁷

Multi-institutional registries could improve understanding of acral melanoma in Black patients.⁴ More studies are needed to help differentiate between the dermoscopic finding of PRP in benign ethnic melanosis vs malignant melanoma.

The Comparison

A Plantar hyperpigmentation (benign ethnic melanosis) on the sole of the foot in a 62-year-old man of African descent with deeply pigmented skin. Dermoscopy showed a parallel ridge pattern even though the hyperpigmentation was benign (inset).

B Melanoma in situ with multicomponent hyperpigmentation on the sole of the foot in a 65-year-old Hispanic woman. Dermoscopy revealed a parallel ridge pattern (inset).

bufrish

Plantar hyperpigmentation (also known as plantar melanosis [increased melanin], volar pigmented macules, benign racial melanosis, acral pigmentation, acral ethnic melanosis, or mottled hyperpigmentation of the plantar surface) is a benign finding in many individuals and is especially prevalent in those with darker skin tones. Acral refers to manifestation on the hands and feet, volar on the palms and soles, and plantar on the soles only. Here, we focus on plantar hyperpigmentation. We use the terms ethnic and racial interchangeably.

It is critically important to differentiate benign hyperpigmentation, which is common in patients with skin of color, from melanoma. Although rare, Black patients in the United States experience high morbidity and mortality from acral melanoma, which often is diagnosed late in the disease course.¹

There are many causes of hyperpigmentation on the plantar surfaces, including benign ethnic melanosis, nevi, melanoma, infections such as syphilis and tinea nigra, conditions such as Peutz-Jeghers syndrome and Laugier-Hunziker syndrome, and postinflammatory hyperpigmentation secondary to atopic dermatitis and psoriasis. We focus on the most common causes, ethnic melanosis and nevi, as well as melanoma, which is the deadliest cause.

Epidemiology

In a 1980 study (N=251), Black Americans had a high incidence of plantar hyperpigmentation, with 52% of affected patients having dark brown skin and 31% having light brown skin.²

The epidemiology of melanoma varies by race/ethnicity. Melanoma in Black individuals is relatively rare, with an annual incidence of approximately 1 in 100,000 individuals.³ However, when individuals with skin of color develop melanoma, they are more likely than their White counterparts to have acral melanoma (acral lentiginous melanoma), one of the deadliest types.¹ In a case series of Black patients with melanoma (N=48) from 2 tertiary care centers in Texas, 30 of 40 primary cutaneous melanomas (75%) were located on acral skin.⁴ Overall, 13 patients developed stage IV disease and 12 died due to disease progression. All patients who developed distant metastases or died of melanoma had acral melanoma.⁴ Individuals of Asian descent also have a high incidence of acral melanoma, as shown in research from Japan.^5-9

Key clinical features in individuals with darker skin tones

Dermoscopy is an evidence-based clinical examination method for earlier diagnosis of cutaneous melanoma, including on acral skin.^10,11 Benign nevi on the volar skin as well as the palms and soles tend to have one of these 3 dermoscopic patterns: parallel furrow, lattice, or irregular fibrillar. The pattern that is most predictive of volar melanoma is the parallel ridge pattern (PRP) (Figures A and B [insets]), which showed a high specificity (99.0%) and very high negative predictive value (97.7%) for malignant melanoma in a Japanese population.⁷ The PRP data from this study cannot be applied reliably to Black individuals, especially because benign ethnic melanosis and other benign conditions can demonstrate PRP.¹² Reliance on the PRP as a diagnostic clue could result in unneccessary biopsies in as many as 50% of Black patients with benign plantar hyperpigmentation.² Furthermore, biopsies of the plantar surface can be painful and cause pain while walking.

It has been suggested that PRP seen on dermoscopy in benign hyperpigmentation such as ethnic melanosis and nevi may preserve the acrosyringia (eccrine gland openings on the ridge), whereas PRP in melanoma may obliterate the acrosyringia.¹³ This observation is based on case reports only and needs further study. However, if validated, it could be a useful diagnostic clue.

Worth noting

In a retrospective cohort study of skin cancer in Black individuals (n=165) at a New York City–based cancer center from 2000 to 2020, 68% of patients were diagnosed with melanomas—80% were the acral subtype and 75% displayed a PRP. However, the surrounding uninvolved background skin, which was visible in most cases, also demonstrated a PRP.¹⁴ Because of the high morbidity and mortality rates of acral melanoma, clinicians should biopsy or immediately refer patients with concerning plantar hyperpigmentation to a dermatologist.

Health disparity highlight

The mortality rate for acral melanoma in Black patients is disproportionately high for the following reasons^15,16:

• Patients and health care providers do not expect to see melanoma in Black patients (it truly is rare!), so screening and education on sun protection are limited.
• Benign ethnic melanosis makes it more difficult to distinguish between early acral melanoma and benign skin changes.
• Black patients and other US patient populations with skin of color may be less likely to have health insurance, which contributes to inequities in access to health care. As of 2022, the uninsured rates for nonelderly American Indian and Alaska Native, Hispanic, Native Hawaiian and Other Pacific Islander, Black, and White individuals were 19.1%, 18.0%, 12.7%, 10.0%, and 6.6%, respectively.¹⁷

Multi-institutional registries could improve understanding of acral melanoma in Black patients.⁴ More studies are needed to help differentiate between the dermoscopic finding of PRP in benign ethnic melanosis vs malignant melanoma.

To the Editor:

Tinea capitis is a common childhood infection seen worldwide and is more prevalent in children of African descent.¹ Treatment can be effective; however, the diagnosis may be delayed due to variability in presentation, camouflage of scalp scale with ointment, and the diagnostic experience of the provider. A common complication of tinea capitis is the dermatophytid (id) reaction, which commonly manifests as multiple 1- to 2-mm monomorphic papules. We report a case of a papulosquamous variant of an id reaction secondary to tinea capitis.

An 8-year-old African American child presented with annular hyperpigmented patches on the face and trunk of several months’ duration. There was no preceding fever, illness, scalp pruritus, or alopecia according to the patient’s mother. The hyperpigmented patches persisted despite use of hydrocortisone and antifungal creams prescribed by a primary care provider. A fungal culture of a scalp specimen was negative. Physical examination during the initial dermatology visit revealed multiple annular hyperpigmented patches on the trunk and extremities. No plaques were evident; however, the mother reported that when the lesions first developed, they were raised and mildly pruritic. The patient was prescribed triamcinolone ointment 0.1% twice daily as needed for itching, and sun protection was emphasized.

At the follow-up visit weeks later, the patient’s mother reported that the ointment had helped the lesions resolve faster, but new lesions continued to appear. Physical examination at this visit was notable for scattered hyperpigmented patches, annular hyperpigmented plaques, and erythematous plaques on the trunk, arms, and legs, in addition to papulosquamous plaques and hyperpigmented patches on the forehead (Figure 1). Suspicion for tinea capitis was discussed, a repeat scalp fungal culture was performed, and oral terbinafine 250 mg once daily was started empirically. The culture was positive for Trichophyton tonsurans supporting the diagnosis of concomitant tinea capitis. The rash resolved with terbinafine, and annular patches of postinflammatory hyperpigmentation remained.

CT113003020_e_ABC.jpg

Dermatophytid reactions are immunologically mediated, disseminated, eczematous eruptions occurring after cutaneous infections or inflammatory skin conditions. Reactions occur days to weeks after exposure to antigens of dermatophytes causing tinea pedis or capitis.²

Common culprits include Microsporum canis and T tonsurans.³ Dermatophytid reactions with tinea capitis exhibit morphologic variability including a symmetric distribution of grouped or diffuse,⁴ pruritic, erythematous or flesh-colored, follicular papules on the trunk, with or without progression to the face, torso, upper extremities, and/or lower extremities.³ Other reported manifestations include erythema multiforme, erythema nodosum,³ or lupuslike lesions, and crops of dyshidrotic vesicles on the hands in the setting of Trichophyton mentagrophytes–induced tinea pedis.⁵

The papulosquamous variant id reaction should be considered in a wider differential that includes psoriasis, nummular eczema, and pityriasis rosea. Unlike psoriasis, the id reaction is not chronic and responds to systemic antifungal therapy. Nummular eczema can be ruled out, though not entirely, by a lack of personal or family history of atopy. The characteristic cleavage lines of pityriasis rosea on the trunk are absent in patients with an id reaction, and there would be no preceding illness or herald patches seen in the id reaction.

Tinea capitis may cause a variety of id manifestations, including the papulosquamous phenotype. This case addresses practice gaps that may lead to delayed diagnosis. It also highlights the importance of recognizing uncommon morphologies, performing repeat cultures of the scalp after a negative fungal culture, and lowering the threshold of suspicion for tinea capitis in the appropriate age group and demographic, specifically pediatric patients of African descent.

To the Editor:

Tinea capitis is a common childhood infection seen worldwide and is more prevalent in children of African descent.¹ Treatment can be effective; however, the diagnosis may be delayed due to variability in presentation, camouflage of scalp scale with ointment, and the diagnostic experience of the provider. A common complication of tinea capitis is the dermatophytid (id) reaction, which commonly manifests as multiple 1- to 2-mm monomorphic papules. We report a case of a papulosquamous variant of an id reaction secondary to tinea capitis.

An 8-year-old African American child presented with annular hyperpigmented patches on the face and trunk of several months’ duration. There was no preceding fever, illness, scalp pruritus, or alopecia according to the patient’s mother. The hyperpigmented patches persisted despite use of hydrocortisone and antifungal creams prescribed by a primary care provider. A fungal culture of a scalp specimen was negative. Physical examination during the initial dermatology visit revealed multiple annular hyperpigmented patches on the trunk and extremities. No plaques were evident; however, the mother reported that when the lesions first developed, they were raised and mildly pruritic. The patient was prescribed triamcinolone ointment 0.1% twice daily as needed for itching, and sun protection was emphasized.

At the follow-up visit weeks later, the patient’s mother reported that the ointment had helped the lesions resolve faster, but new lesions continued to appear. Physical examination at this visit was notable for scattered hyperpigmented patches, annular hyperpigmented plaques, and erythematous plaques on the trunk, arms, and legs, in addition to papulosquamous plaques and hyperpigmented patches on the forehead (Figure 1). Suspicion for tinea capitis was discussed, a repeat scalp fungal culture was performed, and oral terbinafine 250 mg once daily was started empirically. The culture was positive for Trichophyton tonsurans supporting the diagnosis of concomitant tinea capitis. The rash resolved with terbinafine, and annular patches of postinflammatory hyperpigmentation remained.

CT113003020_e_ABC.jpg

Dermatophytid reactions are immunologically mediated, disseminated, eczematous eruptions occurring after cutaneous infections or inflammatory skin conditions. Reactions occur days to weeks after exposure to antigens of dermatophytes causing tinea pedis or capitis.²

Common culprits include Microsporum canis and T tonsurans.³ Dermatophytid reactions with tinea capitis exhibit morphologic variability including a symmetric distribution of grouped or diffuse,⁴ pruritic, erythematous or flesh-colored, follicular papules on the trunk, with or without progression to the face, torso, upper extremities, and/or lower extremities.³ Other reported manifestations include erythema multiforme, erythema nodosum,³ or lupuslike lesions, and crops of dyshidrotic vesicles on the hands in the setting of Trichophyton mentagrophytes–induced tinea pedis.⁵

The papulosquamous variant id reaction should be considered in a wider differential that includes psoriasis, nummular eczema, and pityriasis rosea. Unlike psoriasis, the id reaction is not chronic and responds to systemic antifungal therapy. Nummular eczema can be ruled out, though not entirely, by a lack of personal or family history of atopy. The characteristic cleavage lines of pityriasis rosea on the trunk are absent in patients with an id reaction, and there would be no preceding illness or herald patches seen in the id reaction.

Tinea capitis may cause a variety of id manifestations, including the papulosquamous phenotype. This case addresses practice gaps that may lead to delayed diagnosis. It also highlights the importance of recognizing uncommon morphologies, performing repeat cultures of the scalp after a negative fungal culture, and lowering the threshold of suspicion for tinea capitis in the appropriate age group and demographic, specifically pediatric patients of African descent.

To the Editor:

Tinea capitis is a common childhood infection seen worldwide and is more prevalent in children of African descent.¹ Treatment can be effective; however, the diagnosis may be delayed due to variability in presentation, camouflage of scalp scale with ointment, and the diagnostic experience of the provider. A common complication of tinea capitis is the dermatophytid (id) reaction, which commonly manifests as multiple 1- to 2-mm monomorphic papules. We report a case of a papulosquamous variant of an id reaction secondary to tinea capitis.

An 8-year-old African American child presented with annular hyperpigmented patches on the face and trunk of several months’ duration. There was no preceding fever, illness, scalp pruritus, or alopecia according to the patient’s mother. The hyperpigmented patches persisted despite use of hydrocortisone and antifungal creams prescribed by a primary care provider. A fungal culture of a scalp specimen was negative. Physical examination during the initial dermatology visit revealed multiple annular hyperpigmented patches on the trunk and extremities. No plaques were evident; however, the mother reported that when the lesions first developed, they were raised and mildly pruritic. The patient was prescribed triamcinolone ointment 0.1% twice daily as needed for itching, and sun protection was emphasized.

At the follow-up visit weeks later, the patient’s mother reported that the ointment had helped the lesions resolve faster, but new lesions continued to appear. Physical examination at this visit was notable for scattered hyperpigmented patches, annular hyperpigmented plaques, and erythematous plaques on the trunk, arms, and legs, in addition to papulosquamous plaques and hyperpigmented patches on the forehead (Figure 1). Suspicion for tinea capitis was discussed, a repeat scalp fungal culture was performed, and oral terbinafine 250 mg once daily was started empirically. The culture was positive for Trichophyton tonsurans supporting the diagnosis of concomitant tinea capitis. The rash resolved with terbinafine, and annular patches of postinflammatory hyperpigmentation remained.

CT113003020_e_ABC.jpg

Dermatophytid reactions are immunologically mediated, disseminated, eczematous eruptions occurring after cutaneous infections or inflammatory skin conditions. Reactions occur days to weeks after exposure to antigens of dermatophytes causing tinea pedis or capitis.²

Common culprits include Microsporum canis and T tonsurans.³ Dermatophytid reactions with tinea capitis exhibit morphologic variability including a symmetric distribution of grouped or diffuse,⁴ pruritic, erythematous or flesh-colored, follicular papules on the trunk, with or without progression to the face, torso, upper extremities, and/or lower extremities.³ Other reported manifestations include erythema multiforme, erythema nodosum,³ or lupuslike lesions, and crops of dyshidrotic vesicles on the hands in the setting of Trichophyton mentagrophytes–induced tinea pedis.⁵

The papulosquamous variant id reaction should be considered in a wider differential that includes psoriasis, nummular eczema, and pityriasis rosea. Unlike psoriasis, the id reaction is not chronic and responds to systemic antifungal therapy. Nummular eczema can be ruled out, though not entirely, by a lack of personal or family history of atopy. The characteristic cleavage lines of pityriasis rosea on the trunk are absent in patients with an id reaction, and there would be no preceding illness or herald patches seen in the id reaction.

Tinea capitis may cause a variety of id manifestations, including the papulosquamous phenotype. This case addresses practice gaps that may lead to delayed diagnosis. It also highlights the importance of recognizing uncommon morphologies, performing repeat cultures of the scalp after a negative fungal culture, and lowering the threshold of suspicion for tinea capitis in the appropriate age group and demographic, specifically pediatric patients of African descent.

CT113003143_ABC.jpg

THE COMPARISON

A Melanoma in situ manifesting as longitudinal melanonychia (LM) in a single digit in a Black man. Dermoscopy showed irregular dark bands of brown pigmentation and micro-Hutchinson sign on the cuticle (inset).

B Melanoma manifesting as LM with a prominent Hutchinson sign in a Hispanic man, with variable shades of brown covering more than 50% of the nail width.

C Longitudinal melanonychia of at least 2 nails with a pseudo-Hutchinson sign (pigment on the nail folds in a benign case of LM) in a young Black man demonstrating ethnic/racial melanosis. The longitudinal bands, which were caused by benign melanocytic activation, are more gray than brown and are less than 3 mm wide.

Longitudinal melanonychia (LM) is a pigmented linear band—brown, black, or gray—spanning the length of the nail plate due to the presence of excess melanin, which may be attributed to a benign or malignant process and may warrant further investigation.^1,2 The majority of patients who present with LM are diagnosed with melanocytic activation of the nail matrix due to their inherent darker skin tone or various triggers including trauma, infection, and medications. Longitudinal melanonychia secondary to melanocytic activation often occurs spontaneously in patients with skin of color.³ Less commonly, LM is caused by a nail matrix nevus or lentigo; however, LM may arise secondary to subungual melanoma, a more dangerous cause.

A thorough clinical history including duration, recent changes in LM manifestation, nail trauma, or infection is helpful in evaluating patients with LM; however, a history of nail trauma can be misleading, as nail changes attributed to the trauma may in fact be melanoma. Irregularly spaced vertical lines of pigmentation ranging from brown to black with variations in spacing and width are characteristic of subungual melanoma.⁴ Nail dystrophy, granular hyperpigmentation, and Hutchinson sign (extension of pigmentation to the nail folds) also are worrisome features.⁵ In recent years, dermoscopy has become an important tool in the clinical examination of LM, with the development of criteria based on color and pattern recognition.^5,6 Dermoscopy can be useful in screening potential candidates for biopsy. Although clinical examination and dermoscopy are essential to evaluating LM, the gold-standard diagnostic test when malignancy is suspected is a nail matrix biopsy.^1,2,6,7

Epidemiology

It is not unusual for patients with darker skin tones to develop LM due to melanocytic activation of multiple nails with age. This finding can be seen in approximately 80% of African American individuals, 30% of Japanese individuals, and 50% of Hispanic individuals.² It has even been reported that approximately 100% of Black patients older than 50 years will have evidence of LM.³

In a retrospective analysis, children presenting with LM tend to have a higher prevalence of nail matrix nevi compared to adults (56.1% [60/106] vs 34.3% [23/66]; P=.005).⁸ Involvement of a single digit in children is most likely indicative of a nevus; however, when an adult presents with LM in a single digit, suspicion for subungual melanoma should be raised.^2,3,9

Two separate single-center retrospective studies showed the prevalence of subungual melanoma in patients presenting with melanonychia in Asia. Jin et al10 reported subungual melanoma in 6.2% (17/275) of Korean patients presenting with melanonychia at a general dermatology clinic from 2002 to 2014. Lyu et al⁸ studied LM in 172 Chinese patients in a dermatology clinic from 2018 to 2021 and reported 9% (6/66) of adults (aged ≥18 years) with subungual melanoma, with no reported cases in childhood (aged <18 years).

Although the prevalence of subungual melanoma in patients with LM is low, it is an important diagnosis that should not be missed. In confirmed cases of subungual melanoma, two-thirds of lesions manifested as LM.^3,10,11 Thus, LM arising in an adult in a single digit is more concerning for malignancy.^2,3,7,9

Individuals of African and Asian descent as well as American Indian individuals are at highest risk for subungual melanoma with a poor prognosis compared to other types of melanoma, largely due to diagnosis at an advanced stage of disease.^3,9 In a retrospective study of 25 patients with surgically treated subungual melanoma, the mean recurrence-free survival was 33.6 months. The recurrence-free survival was 66% at 1 year and 40% at 3 years, and the overall survival rate was 37% at 3 years.¹²

Key clinical features in individuals with darker skin tones

• In patients with darker skin tones, LM tends to occur on multiple nails as a result of melanocytic activation.^2,13
• Several longitudinal bands may be noted on the same nail and the pigmentation of the bands may vary. With age, these longitudinal bands typically increase in number and width.¹³
• Pseudo-Hutchinson sign may be present due to ethnic melanosis of the proximal nail fold.^13,14
• Dermoscopic findings of LM in patients with skin of color include wider bands (P=.0125), lower band brightness (P<.032), and higher frequency of changing appearance of bands (P=.0071).¹⁵

Worth noting

When patients present with LM, thorough examination of the nail plate, periungual skin, and distal pulp of all digits on all extremities with adequate lighting is important.² Dermoscopy is useful, and a gel interface helps for examining the nail plates.⁷

Clinicians should be encouraged to biopsy or immediately refer patients with concerning nail unit lesions. Cases of LM most likely are benign, but if some doubt exists, the lesions should be biopsied or tracked closely with clinical and dermoscopic images, with a biopsy if changes occur.¹⁶ In conjunction with evaluation by a qualified clinician, patients also should be encouraged to take photographs, as the evolution of nail changes is a critical part of clinical decision-making on the need for a biopsy or referral.

Health disparity highlight

Despite the disproportionately high mortality rates from subungual melanoma in Black and Hispanic populations,^3,9 studies often do not adequately represent these populations. Although subungual melanoma is rare, a delay in the diagnosis contributes to high morbidity and mortality rates.

CT113003143_ABC.jpg

THE COMPARISON

A Melanoma in situ manifesting as longitudinal melanonychia (LM) in a single digit in a Black man. Dermoscopy showed irregular dark bands of brown pigmentation and micro-Hutchinson sign on the cuticle (inset).

B Melanoma manifesting as LM with a prominent Hutchinson sign in a Hispanic man, with variable shades of brown covering more than 50% of the nail width.

C Longitudinal melanonychia of at least 2 nails with a pseudo-Hutchinson sign (pigment on the nail folds in a benign case of LM) in a young Black man demonstrating ethnic/racial melanosis. The longitudinal bands, which were caused by benign melanocytic activation, are more gray than brown and are less than 3 mm wide.

Longitudinal melanonychia (LM) is a pigmented linear band—brown, black, or gray—spanning the length of the nail plate due to the presence of excess melanin, which may be attributed to a benign or malignant process and may warrant further investigation.^1,2 The majority of patients who present with LM are diagnosed with melanocytic activation of the nail matrix due to their inherent darker skin tone or various triggers including trauma, infection, and medications. Longitudinal melanonychia secondary to melanocytic activation often occurs spontaneously in patients with skin of color.³ Less commonly, LM is caused by a nail matrix nevus or lentigo; however, LM may arise secondary to subungual melanoma, a more dangerous cause.

A thorough clinical history including duration, recent changes in LM manifestation, nail trauma, or infection is helpful in evaluating patients with LM; however, a history of nail trauma can be misleading, as nail changes attributed to the trauma may in fact be melanoma. Irregularly spaced vertical lines of pigmentation ranging from brown to black with variations in spacing and width are characteristic of subungual melanoma.⁴ Nail dystrophy, granular hyperpigmentation, and Hutchinson sign (extension of pigmentation to the nail folds) also are worrisome features.⁵ In recent years, dermoscopy has become an important tool in the clinical examination of LM, with the development of criteria based on color and pattern recognition.^5,6 Dermoscopy can be useful in screening potential candidates for biopsy. Although clinical examination and dermoscopy are essential to evaluating LM, the gold-standard diagnostic test when malignancy is suspected is a nail matrix biopsy.^1,2,6,7

Epidemiology

It is not unusual for patients with darker skin tones to develop LM due to melanocytic activation of multiple nails with age. This finding can be seen in approximately 80% of African American individuals, 30% of Japanese individuals, and 50% of Hispanic individuals.² It has even been reported that approximately 100% of Black patients older than 50 years will have evidence of LM.³

In a retrospective analysis, children presenting with LM tend to have a higher prevalence of nail matrix nevi compared to adults (56.1% [60/106] vs 34.3% [23/66]; P=.005).⁸ Involvement of a single digit in children is most likely indicative of a nevus; however, when an adult presents with LM in a single digit, suspicion for subungual melanoma should be raised.^2,3,9

Two separate single-center retrospective studies showed the prevalence of subungual melanoma in patients presenting with melanonychia in Asia. Jin et al10 reported subungual melanoma in 6.2% (17/275) of Korean patients presenting with melanonychia at a general dermatology clinic from 2002 to 2014. Lyu et al⁸ studied LM in 172 Chinese patients in a dermatology clinic from 2018 to 2021 and reported 9% (6/66) of adults (aged ≥18 years) with subungual melanoma, with no reported cases in childhood (aged <18 years).

Although the prevalence of subungual melanoma in patients with LM is low, it is an important diagnosis that should not be missed. In confirmed cases of subungual melanoma, two-thirds of lesions manifested as LM.^3,10,11 Thus, LM arising in an adult in a single digit is more concerning for malignancy.^2,3,7,9

Individuals of African and Asian descent as well as American Indian individuals are at highest risk for subungual melanoma with a poor prognosis compared to other types of melanoma, largely due to diagnosis at an advanced stage of disease.^3,9 In a retrospective study of 25 patients with surgically treated subungual melanoma, the mean recurrence-free survival was 33.6 months. The recurrence-free survival was 66% at 1 year and 40% at 3 years, and the overall survival rate was 37% at 3 years.¹²

Key clinical features in individuals with darker skin tones

• In patients with darker skin tones, LM tends to occur on multiple nails as a result of melanocytic activation.^2,13
• Several longitudinal bands may be noted on the same nail and the pigmentation of the bands may vary. With age, these longitudinal bands typically increase in number and width.¹³
• Pseudo-Hutchinson sign may be present due to ethnic melanosis of the proximal nail fold.^13,14
• Dermoscopic findings of LM in patients with skin of color include wider bands (P=.0125), lower band brightness (P<.032), and higher frequency of changing appearance of bands (P=.0071).¹⁵

Worth noting

When patients present with LM, thorough examination of the nail plate, periungual skin, and distal pulp of all digits on all extremities with adequate lighting is important.² Dermoscopy is useful, and a gel interface helps for examining the nail plates.⁷

Clinicians should be encouraged to biopsy or immediately refer patients with concerning nail unit lesions. Cases of LM most likely are benign, but if some doubt exists, the lesions should be biopsied or tracked closely with clinical and dermoscopic images, with a biopsy if changes occur.¹⁶ In conjunction with evaluation by a qualified clinician, patients also should be encouraged to take photographs, as the evolution of nail changes is a critical part of clinical decision-making on the need for a biopsy or referral.

Health disparity highlight

Despite the disproportionately high mortality rates from subungual melanoma in Black and Hispanic populations,^3,9 studies often do not adequately represent these populations. Although subungual melanoma is rare, a delay in the diagnosis contributes to high morbidity and mortality rates.

CT113003143_ABC.jpg

THE COMPARISON

A Melanoma in situ manifesting as longitudinal melanonychia (LM) in a single digit in a Black man. Dermoscopy showed irregular dark bands of brown pigmentation and micro-Hutchinson sign on the cuticle (inset).

B Melanoma manifesting as LM with a prominent Hutchinson sign in a Hispanic man, with variable shades of brown covering more than 50% of the nail width.

C Longitudinal melanonychia of at least 2 nails with a pseudo-Hutchinson sign (pigment on the nail folds in a benign case of LM) in a young Black man demonstrating ethnic/racial melanosis. The longitudinal bands, which were caused by benign melanocytic activation, are more gray than brown and are less than 3 mm wide.

Longitudinal melanonychia (LM) is a pigmented linear band—brown, black, or gray—spanning the length of the nail plate due to the presence of excess melanin, which may be attributed to a benign or malignant process and may warrant further investigation.^1,2 The majority of patients who present with LM are diagnosed with melanocytic activation of the nail matrix due to their inherent darker skin tone or various triggers including trauma, infection, and medications. Longitudinal melanonychia secondary to melanocytic activation often occurs spontaneously in patients with skin of color.³ Less commonly, LM is caused by a nail matrix nevus or lentigo; however, LM may arise secondary to subungual melanoma, a more dangerous cause.

A thorough clinical history including duration, recent changes in LM manifestation, nail trauma, or infection is helpful in evaluating patients with LM; however, a history of nail trauma can be misleading, as nail changes attributed to the trauma may in fact be melanoma. Irregularly spaced vertical lines of pigmentation ranging from brown to black with variations in spacing and width are characteristic of subungual melanoma.⁴ Nail dystrophy, granular hyperpigmentation, and Hutchinson sign (extension of pigmentation to the nail folds) also are worrisome features.⁵ In recent years, dermoscopy has become an important tool in the clinical examination of LM, with the development of criteria based on color and pattern recognition.^5,6 Dermoscopy can be useful in screening potential candidates for biopsy. Although clinical examination and dermoscopy are essential to evaluating LM, the gold-standard diagnostic test when malignancy is suspected is a nail matrix biopsy.^1,2,6,7

Epidemiology

It is not unusual for patients with darker skin tones to develop LM due to melanocytic activation of multiple nails with age. This finding can be seen in approximately 80% of African American individuals, 30% of Japanese individuals, and 50% of Hispanic individuals.² It has even been reported that approximately 100% of Black patients older than 50 years will have evidence of LM.³

In a retrospective analysis, children presenting with LM tend to have a higher prevalence of nail matrix nevi compared to adults (56.1% [60/106] vs 34.3% [23/66]; P=.005).⁸ Involvement of a single digit in children is most likely indicative of a nevus; however, when an adult presents with LM in a single digit, suspicion for subungual melanoma should be raised.^2,3,9

Two separate single-center retrospective studies showed the prevalence of subungual melanoma in patients presenting with melanonychia in Asia. Jin et al10 reported subungual melanoma in 6.2% (17/275) of Korean patients presenting with melanonychia at a general dermatology clinic from 2002 to 2014. Lyu et al⁸ studied LM in 172 Chinese patients in a dermatology clinic from 2018 to 2021 and reported 9% (6/66) of adults (aged ≥18 years) with subungual melanoma, with no reported cases in childhood (aged <18 years).

Although the prevalence of subungual melanoma in patients with LM is low, it is an important diagnosis that should not be missed. In confirmed cases of subungual melanoma, two-thirds of lesions manifested as LM.^3,10,11 Thus, LM arising in an adult in a single digit is more concerning for malignancy.^2,3,7,9

Individuals of African and Asian descent as well as American Indian individuals are at highest risk for subungual melanoma with a poor prognosis compared to other types of melanoma, largely due to diagnosis at an advanced stage of disease.^3,9 In a retrospective study of 25 patients with surgically treated subungual melanoma, the mean recurrence-free survival was 33.6 months. The recurrence-free survival was 66% at 1 year and 40% at 3 years, and the overall survival rate was 37% at 3 years.¹²

Key clinical features in individuals with darker skin tones

• In patients with darker skin tones, LM tends to occur on multiple nails as a result of melanocytic activation.^2,13
• Several longitudinal bands may be noted on the same nail and the pigmentation of the bands may vary. With age, these longitudinal bands typically increase in number and width.¹³
• Pseudo-Hutchinson sign may be present due to ethnic melanosis of the proximal nail fold.^13,14
• Dermoscopic findings of LM in patients with skin of color include wider bands (P=.0125), lower band brightness (P<.032), and higher frequency of changing appearance of bands (P=.0071).¹⁵

Worth noting

When patients present with LM, thorough examination of the nail plate, periungual skin, and distal pulp of all digits on all extremities with adequate lighting is important.² Dermoscopy is useful, and a gel interface helps for examining the nail plates.⁷

Clinicians should be encouraged to biopsy or immediately refer patients with concerning nail unit lesions. Cases of LM most likely are benign, but if some doubt exists, the lesions should be biopsied or tracked closely with clinical and dermoscopic images, with a biopsy if changes occur.¹⁶ In conjunction with evaluation by a qualified clinician, patients also should be encouraged to take photographs, as the evolution of nail changes is a critical part of clinical decision-making on the need for a biopsy or referral.

Health disparity highlight

Despite the disproportionately high mortality rates from subungual melanoma in Black and Hispanic populations,^3,9 studies often do not adequately represent these populations. Although subungual melanoma is rare, a delay in the diagnosis contributes to high morbidity and mortality rates.

THE COMPARISON

A An 11-year-old Hispanic boy with allergic contact dermatitis (ACD) on the abdomen. The geometric nature of the eruption and proximity to the belt buckle were highly suggestive of ACD to nickel; patch testing was not needed.

B A Black woman with ACD on the neck. A punch biopsy demonstrated spongiotic dermatitis that was typical of ACD. The diagnosis was supported by the patient’s history of dermatitis that developed after new products were applied to the hair. The patient declined patch testing.

C A Hispanic man with ACD on hair-bearing areas of the face where hair dye was used. The patient’s history of dermatitis following the application of hair dye was highly suggestive of ACD; patch testing confirmed the allergen was paraphenylenediamine (PPD).

Allergic contact dermatitis (ACD) is an inflammatory condition of the skin caused by an immunologic response to 1 or more identifiable allergens. A delayed-type immune response (type IV hypersensitivity reaction) occurs after the skin is re-exposed to an offending allergen.¹ Severe pruritus is the main symptom of ACD in the early stages, accompanied by erythema, vesicles, and scaling in a distinct pattern corresponding to the allergen’s contact with the skin.² Delayed widespread dermatitis after exposure to an allergen—a phenomenon known as autoeczematization (id reaction)—also may occur.³

The gold-standard diagnostic tool for ACD is patch testing, in which the patient is re-exposed to the suspected contact allergen(s) and observed for the development of dermatitis.⁴ However, ACD can be diagnosed with a detailed patient history including occupation, hobbies, personal care practices, and possible triggers with subsequent rashes. Thorough clinical examination of the skin is paramount. Indicators of possible ACD include dermatitis that persists despite use of appropriate treatment, an unexplained flare of previously quiescent dermatitis, and a diagnosis of dermatitis without a clear cause.¹

Hairdressers, health care workers, and metal workers are at higher risk for ACD.⁵ Occupational ACD has notable socioeconomic implications, as it can result in frequent sick days, inability to perform tasks at work, and in some cases job loss.⁶

Patients with atopic dermatitis have impaired barrier function of the skin, permitting the entrance of allergens and subsequent sensitization.⁷ ACD is a challenge to manage, as complete avoidance of the allergen may not be possible.⁸

Continue to: The underrepresentation of patients...

The underrepresentation of patients with skin of color (SOC) in educational materials as well as socioeconomic health disparities may contribute to the lower rates of diagnosis, patch testing, and treatment of ACD in this patient population.

Epidemiology

An ACD prevalence of 15.2% was reported in a study of 793 Danish patients who underwent skin prick and patch testing.⁹ Alinaghi et al¹⁰ conducted a meta-analysis of 20,107 patients across 28 studies who were patch tested to determine the prevalence of ACD in the general population. The researchers concluded that 20.1% (95% CI, 16.8%-23.7%) of the general population experienced ACD. They analyzed 22 studies to determine the prevalence of ACD based on specific geographic area, including 18,709 individuals from Europe with a prevalence of 19.5% (95% CI, 15.8%-23.4%), 1639 individuals from North America with a prevalence of 20.6% (95% CI, 9.2%-35.2%), and 2 studies from China (no other studies from Asia found) with a prevalence of 20.6% (95% CI, 17.4%-23.9%). Researchers did not find data from studies conducted in Africa or South America.¹⁰

The current available epidemiologic data on ACD are not representative of SOC populations. DeLeo et al¹¹ looked at patch test reaction patterns in association with race and ethnicity in a large sample size (N = 19,457); 92.9% of these patients were White and only 7.1% were Black. Large-scale, inclusive studies are needed, which can only be achieved with increased suspicion for ACD and increased access to patch testing.

ACD is more common in women, with nickel being the most frequently identified allergen (FIGURE A).¹⁰ Personal care products often are linked to ACD (FIGURE B). An analysis of data from the North American Contact Dermatitis Group revealed that the top 5 personal care product allergens were methylisothiazolinone (a preservative), fragrance mix I, balsam of Peru, quaternium-15 (a preservative), and paraphenylenediamine (PPD; a common component of hair dye) (FIGURE C).¹²

JFP07210350_f.jpg

There is a paucity of epidemiologic data among various ethnic groups; however, a few studies have suggested that there is no difference in the frequency rates of positive patch test results in Black vs White populations.^11,13,14 One study of patch test results from 114 Black patients and 877 White patients at the Cleveland Clinic Foundation in Ohio demonstrated a similar allergy frequency of 43.0% and 43.6%, respectively.13 However, there were differences in the types of allergen sensitization. Black patients had higher positive patch test rates for PPD than White patients (10.6% vs 4.5%). Black men had a higher frequency of sensitivity to PPD (21.2% vs 4.2%) and imidazolidinyl urea (a formaldehyde-releasing preservative; 9.1% vs 2.6%) compared to White men.¹³

Continue to: Ethnicity and cultural practices...

Ethnicity and cultural practices influence epidemiologic patterns of ACD. Darker hair dyes used in Black patients¹⁴ and deeply pigmented PPD dye found in henna tattoos used in Indian and Black patients¹⁵ may lead to increased sensitization to PPD. ACD due to formaldehyde is more common in White patients, possibly due to more frequent use of formaldehyde-containing moisturizers, shampoos, and creams.¹⁵

Key clinical features in people with darker skin tones

In patients with SOC, the clinical features of ACD vary, posing a diagnostic challenge. Hyperpigmentation, lichenification, and induration are more likely to be seen than the papules, vesicles, and erythematous dermatitis often described in lighter skin tones or acute ACD. Erythema can be difficult to assess on darker skin and may appear violaceous or very faint pink.16

Worth noting

A high index of suspicion is necessary when interpreting patch tests in patients with SOC, as patch test kits use a reading plate with graduated intensities of erythema, papulation, and vesicular reactions to determine the likelihood of ACD. The potential contact allergens are placed on the skin on Day 1 and covered. Then, on Day 3 the allergens are removed. The skin is clinically evaluated using visual assessment and skin palpation. The reactions are graded as negative, irritant reaction, equivocal, weak positive, strong positive, or extreme reaction at around Days 3 and 5 to capture both early and delayed reactions.¹⁷ A patch test may be positive even if obvious signs of erythema are not appreciated as expected.

ACD is more common in women, with nickel being the most frequently identified allergen.

Adjusting the lighting in the examination room, including side lighting, or using a blue background can be helpful in identifying erythema in darker skin tones.^15,16,18 Palpation of the skin also is useful, as even slight texture changes and induration are indicators of a possible skin reaction to the test allergen.¹⁵

Health disparity highlight

Clinical photographs of ACD and patch test results in patients with SOC are not commonplace in the literature. Positive patch test results in patients with darker skin tones vary from those of patients with lighter skin tones, and if the clinician reading the patch test result is not familiar with the findings in darker skin tones, the diagnosis may be delayed or missed.¹⁵

Continue to: Furthermore, Scott et al...

Furthermore, Scott et al¹⁵ highlighted that many dermatology residency training programs have a paucity of SOC education in their curriculum. This lack of representation may contribute to the diagnostic challenges encountered by health care providers.

The lower rates of patch testing in Black patients are likely due to the impact of social determinants of health.

Timely access to health care and education as well as economic stability are essential for the successful management of patients with ACD. Some individuals with SOC have been disproportionately affected by social determinants of health. Rodriguez-Homs et al¹⁹ demonstrated that the distance needed to travel to a clinic and the poverty rate of the county the patient lives in play a role in referral to a clinician specializing in contact dermatitis.

A retrospective registry review of 2310 patients undergoing patch testing at the Massachusetts General Hospital in Boston revealed that 2.5% were Black, 5.5% were Latinx, 8.3% were Asian, and the remaining 83.7% were White.²⁰ Qian et al²¹ also looked at patch testing patterns among various sociodemographic groups (N = 1,107,530) and found that 69% of patients were White and 59% were female. Rates of patch testing among patients who were Black, lesser educated, male, lower income, and younger (children ages 0-12 years) were significantly lower than for other groups when ACD was suspected (P < .0001).²¹ The lower rates of patch testing in patients with SOC may be due to low suspicion of diagnosis, low referral rates due to limited medical insurance, and financial instability, as well as other socioeconomic factors.²⁰

Tamazian et al¹⁶ reviewed pediatric populations at 13 US centers and found that Black children received patch testing less frequently than White and Hispanic children. Another review of pediatric patch testing in patients with SOC found that a less comprehensive panel of allergens was used in this population.²²

The key to resolution of ACD is removal of the offending antigen, and if patients are not being tested, then they risk having a prolonged and complicated course of ACD with a poor prognosis. Patients with SOC also experience greater negative psychosocial impact due to ACD disease burden.^21,23 The lower rates of patch testing in Black patients cannot solely be attributed to difficulty diagnosing ACD in darker skin tones; it is likely due to the impact of social determinants of health. Alleviating health disparities will improve patient outcomes and quality of life.

THE COMPARISON

A An 11-year-old Hispanic boy with allergic contact dermatitis (ACD) on the abdomen. The geometric nature of the eruption and proximity to the belt buckle were highly suggestive of ACD to nickel; patch testing was not needed.

B A Black woman with ACD on the neck. A punch biopsy demonstrated spongiotic dermatitis that was typical of ACD. The diagnosis was supported by the patient’s history of dermatitis that developed after new products were applied to the hair. The patient declined patch testing.

C A Hispanic man with ACD on hair-bearing areas of the face where hair dye was used. The patient’s history of dermatitis following the application of hair dye was highly suggestive of ACD; patch testing confirmed the allergen was paraphenylenediamine (PPD).

Allergic contact dermatitis (ACD) is an inflammatory condition of the skin caused by an immunologic response to 1 or more identifiable allergens. A delayed-type immune response (type IV hypersensitivity reaction) occurs after the skin is re-exposed to an offending allergen.¹ Severe pruritus is the main symptom of ACD in the early stages, accompanied by erythema, vesicles, and scaling in a distinct pattern corresponding to the allergen’s contact with the skin.² Delayed widespread dermatitis after exposure to an allergen—a phenomenon known as autoeczematization (id reaction)—also may occur.³

The gold-standard diagnostic tool for ACD is patch testing, in which the patient is re-exposed to the suspected contact allergen(s) and observed for the development of dermatitis.⁴ However, ACD can be diagnosed with a detailed patient history including occupation, hobbies, personal care practices, and possible triggers with subsequent rashes. Thorough clinical examination of the skin is paramount. Indicators of possible ACD include dermatitis that persists despite use of appropriate treatment, an unexplained flare of previously quiescent dermatitis, and a diagnosis of dermatitis without a clear cause.¹

Hairdressers, health care workers, and metal workers are at higher risk for ACD.⁵ Occupational ACD has notable socioeconomic implications, as it can result in frequent sick days, inability to perform tasks at work, and in some cases job loss.⁶

Patients with atopic dermatitis have impaired barrier function of the skin, permitting the entrance of allergens and subsequent sensitization.⁷ ACD is a challenge to manage, as complete avoidance of the allergen may not be possible.⁸

Continue to: The underrepresentation of patients...

The underrepresentation of patients with skin of color (SOC) in educational materials as well as socioeconomic health disparities may contribute to the lower rates of diagnosis, patch testing, and treatment of ACD in this patient population.

Epidemiology

An ACD prevalence of 15.2% was reported in a study of 793 Danish patients who underwent skin prick and patch testing.⁹ Alinaghi et al¹⁰ conducted a meta-analysis of 20,107 patients across 28 studies who were patch tested to determine the prevalence of ACD in the general population. The researchers concluded that 20.1% (95% CI, 16.8%-23.7%) of the general population experienced ACD. They analyzed 22 studies to determine the prevalence of ACD based on specific geographic area, including 18,709 individuals from Europe with a prevalence of 19.5% (95% CI, 15.8%-23.4%), 1639 individuals from North America with a prevalence of 20.6% (95% CI, 9.2%-35.2%), and 2 studies from China (no other studies from Asia found) with a prevalence of 20.6% (95% CI, 17.4%-23.9%). Researchers did not find data from studies conducted in Africa or South America.¹⁰

The current available epidemiologic data on ACD are not representative of SOC populations. DeLeo et al¹¹ looked at patch test reaction patterns in association with race and ethnicity in a large sample size (N = 19,457); 92.9% of these patients were White and only 7.1% were Black. Large-scale, inclusive studies are needed, which can only be achieved with increased suspicion for ACD and increased access to patch testing.

ACD is more common in women, with nickel being the most frequently identified allergen (FIGURE A).¹⁰ Personal care products often are linked to ACD (FIGURE B). An analysis of data from the North American Contact Dermatitis Group revealed that the top 5 personal care product allergens were methylisothiazolinone (a preservative), fragrance mix I, balsam of Peru, quaternium-15 (a preservative), and paraphenylenediamine (PPD; a common component of hair dye) (FIGURE C).¹²

JFP07210350_f.jpg

There is a paucity of epidemiologic data among various ethnic groups; however, a few studies have suggested that there is no difference in the frequency rates of positive patch test results in Black vs White populations.^11,13,14 One study of patch test results from 114 Black patients and 877 White patients at the Cleveland Clinic Foundation in Ohio demonstrated a similar allergy frequency of 43.0% and 43.6%, respectively.13 However, there were differences in the types of allergen sensitization. Black patients had higher positive patch test rates for PPD than White patients (10.6% vs 4.5%). Black men had a higher frequency of sensitivity to PPD (21.2% vs 4.2%) and imidazolidinyl urea (a formaldehyde-releasing preservative; 9.1% vs 2.6%) compared to White men.¹³

Continue to: Ethnicity and cultural practices...

Ethnicity and cultural practices influence epidemiologic patterns of ACD. Darker hair dyes used in Black patients¹⁴ and deeply pigmented PPD dye found in henna tattoos used in Indian and Black patients¹⁵ may lead to increased sensitization to PPD. ACD due to formaldehyde is more common in White patients, possibly due to more frequent use of formaldehyde-containing moisturizers, shampoos, and creams.¹⁵

Key clinical features in people with darker skin tones

In patients with SOC, the clinical features of ACD vary, posing a diagnostic challenge. Hyperpigmentation, lichenification, and induration are more likely to be seen than the papules, vesicles, and erythematous dermatitis often described in lighter skin tones or acute ACD. Erythema can be difficult to assess on darker skin and may appear violaceous or very faint pink.16

Worth noting

A high index of suspicion is necessary when interpreting patch tests in patients with SOC, as patch test kits use a reading plate with graduated intensities of erythema, papulation, and vesicular reactions to determine the likelihood of ACD. The potential contact allergens are placed on the skin on Day 1 and covered. Then, on Day 3 the allergens are removed. The skin is clinically evaluated using visual assessment and skin palpation. The reactions are graded as negative, irritant reaction, equivocal, weak positive, strong positive, or extreme reaction at around Days 3 and 5 to capture both early and delayed reactions.¹⁷ A patch test may be positive even if obvious signs of erythema are not appreciated as expected.

ACD is more common in women, with nickel being the most frequently identified allergen.

Adjusting the lighting in the examination room, including side lighting, or using a blue background can be helpful in identifying erythema in darker skin tones.^15,16,18 Palpation of the skin also is useful, as even slight texture changes and induration are indicators of a possible skin reaction to the test allergen.¹⁵

Health disparity highlight

Clinical photographs of ACD and patch test results in patients with SOC are not commonplace in the literature. Positive patch test results in patients with darker skin tones vary from those of patients with lighter skin tones, and if the clinician reading the patch test result is not familiar with the findings in darker skin tones, the diagnosis may be delayed or missed.¹⁵

Continue to: Furthermore, Scott et al...

Furthermore, Scott et al¹⁵ highlighted that many dermatology residency training programs have a paucity of SOC education in their curriculum. This lack of representation may contribute to the diagnostic challenges encountered by health care providers.

The lower rates of patch testing in Black patients are likely due to the impact of social determinants of health.

Timely access to health care and education as well as economic stability are essential for the successful management of patients with ACD. Some individuals with SOC have been disproportionately affected by social determinants of health. Rodriguez-Homs et al¹⁹ demonstrated that the distance needed to travel to a clinic and the poverty rate of the county the patient lives in play a role in referral to a clinician specializing in contact dermatitis.

A retrospective registry review of 2310 patients undergoing patch testing at the Massachusetts General Hospital in Boston revealed that 2.5% were Black, 5.5% were Latinx, 8.3% were Asian, and the remaining 83.7% were White.²⁰ Qian et al²¹ also looked at patch testing patterns among various sociodemographic groups (N = 1,107,530) and found that 69% of patients were White and 59% were female. Rates of patch testing among patients who were Black, lesser educated, male, lower income, and younger (children ages 0-12 years) were significantly lower than for other groups when ACD was suspected (P < .0001).²¹ The lower rates of patch testing in patients with SOC may be due to low suspicion of diagnosis, low referral rates due to limited medical insurance, and financial instability, as well as other socioeconomic factors.²⁰

Tamazian et al¹⁶ reviewed pediatric populations at 13 US centers and found that Black children received patch testing less frequently than White and Hispanic children. Another review of pediatric patch testing in patients with SOC found that a less comprehensive panel of allergens was used in this population.²²

The key to resolution of ACD is removal of the offending antigen, and if patients are not being tested, then they risk having a prolonged and complicated course of ACD with a poor prognosis. Patients with SOC also experience greater negative psychosocial impact due to ACD disease burden.^21,23 The lower rates of patch testing in Black patients cannot solely be attributed to difficulty diagnosing ACD in darker skin tones; it is likely due to the impact of social determinants of health. Alleviating health disparities will improve patient outcomes and quality of life.

THE COMPARISON

A An 11-year-old Hispanic boy with allergic contact dermatitis (ACD) on the abdomen. The geometric nature of the eruption and proximity to the belt buckle were highly suggestive of ACD to nickel; patch testing was not needed.

B A Black woman with ACD on the neck. A punch biopsy demonstrated spongiotic dermatitis that was typical of ACD. The diagnosis was supported by the patient’s history of dermatitis that developed after new products were applied to the hair. The patient declined patch testing.

C A Hispanic man with ACD on hair-bearing areas of the face where hair dye was used. The patient’s history of dermatitis following the application of hair dye was highly suggestive of ACD; patch testing confirmed the allergen was paraphenylenediamine (PPD).

Allergic contact dermatitis (ACD) is an inflammatory condition of the skin caused by an immunologic response to 1 or more identifiable allergens. A delayed-type immune response (type IV hypersensitivity reaction) occurs after the skin is re-exposed to an offending allergen.¹ Severe pruritus is the main symptom of ACD in the early stages, accompanied by erythema, vesicles, and scaling in a distinct pattern corresponding to the allergen’s contact with the skin.² Delayed widespread dermatitis after exposure to an allergen—a phenomenon known as autoeczematization (id reaction)—also may occur.³

The gold-standard diagnostic tool for ACD is patch testing, in which the patient is re-exposed to the suspected contact allergen(s) and observed for the development of dermatitis.⁴ However, ACD can be diagnosed with a detailed patient history including occupation, hobbies, personal care practices, and possible triggers with subsequent rashes. Thorough clinical examination of the skin is paramount. Indicators of possible ACD include dermatitis that persists despite use of appropriate treatment, an unexplained flare of previously quiescent dermatitis, and a diagnosis of dermatitis without a clear cause.¹

Hairdressers, health care workers, and metal workers are at higher risk for ACD.⁵ Occupational ACD has notable socioeconomic implications, as it can result in frequent sick days, inability to perform tasks at work, and in some cases job loss.⁶

Patients with atopic dermatitis have impaired barrier function of the skin, permitting the entrance of allergens and subsequent sensitization.⁷ ACD is a challenge to manage, as complete avoidance of the allergen may not be possible.⁸

Continue to: The underrepresentation of patients...

The underrepresentation of patients with skin of color (SOC) in educational materials as well as socioeconomic health disparities may contribute to the lower rates of diagnosis, patch testing, and treatment of ACD in this patient population.

Epidemiology

An ACD prevalence of 15.2% was reported in a study of 793 Danish patients who underwent skin prick and patch testing.⁹ Alinaghi et al¹⁰ conducted a meta-analysis of 20,107 patients across 28 studies who were patch tested to determine the prevalence of ACD in the general population. The researchers concluded that 20.1% (95% CI, 16.8%-23.7%) of the general population experienced ACD. They analyzed 22 studies to determine the prevalence of ACD based on specific geographic area, including 18,709 individuals from Europe with a prevalence of 19.5% (95% CI, 15.8%-23.4%), 1639 individuals from North America with a prevalence of 20.6% (95% CI, 9.2%-35.2%), and 2 studies from China (no other studies from Asia found) with a prevalence of 20.6% (95% CI, 17.4%-23.9%). Researchers did not find data from studies conducted in Africa or South America.¹⁰

The current available epidemiologic data on ACD are not representative of SOC populations. DeLeo et al¹¹ looked at patch test reaction patterns in association with race and ethnicity in a large sample size (N = 19,457); 92.9% of these patients were White and only 7.1% were Black. Large-scale, inclusive studies are needed, which can only be achieved with increased suspicion for ACD and increased access to patch testing.

ACD is more common in women, with nickel being the most frequently identified allergen (FIGURE A).¹⁰ Personal care products often are linked to ACD (FIGURE B). An analysis of data from the North American Contact Dermatitis Group revealed that the top 5 personal care product allergens were methylisothiazolinone (a preservative), fragrance mix I, balsam of Peru, quaternium-15 (a preservative), and paraphenylenediamine (PPD; a common component of hair dye) (FIGURE C).¹²

JFP07210350_f.jpg

There is a paucity of epidemiologic data among various ethnic groups; however, a few studies have suggested that there is no difference in the frequency rates of positive patch test results in Black vs White populations.^11,13,14 One study of patch test results from 114 Black patients and 877 White patients at the Cleveland Clinic Foundation in Ohio demonstrated a similar allergy frequency of 43.0% and 43.6%, respectively.13 However, there were differences in the types of allergen sensitization. Black patients had higher positive patch test rates for PPD than White patients (10.6% vs 4.5%). Black men had a higher frequency of sensitivity to PPD (21.2% vs 4.2%) and imidazolidinyl urea (a formaldehyde-releasing preservative; 9.1% vs 2.6%) compared to White men.¹³

Continue to: Ethnicity and cultural practices...

Ethnicity and cultural practices influence epidemiologic patterns of ACD. Darker hair dyes used in Black patients¹⁴ and deeply pigmented PPD dye found in henna tattoos used in Indian and Black patients¹⁵ may lead to increased sensitization to PPD. ACD due to formaldehyde is more common in White patients, possibly due to more frequent use of formaldehyde-containing moisturizers, shampoos, and creams.¹⁵

Key clinical features in people with darker skin tones

In patients with SOC, the clinical features of ACD vary, posing a diagnostic challenge. Hyperpigmentation, lichenification, and induration are more likely to be seen than the papules, vesicles, and erythematous dermatitis often described in lighter skin tones or acute ACD. Erythema can be difficult to assess on darker skin and may appear violaceous or very faint pink.16

Worth noting

A high index of suspicion is necessary when interpreting patch tests in patients with SOC, as patch test kits use a reading plate with graduated intensities of erythema, papulation, and vesicular reactions to determine the likelihood of ACD. The potential contact allergens are placed on the skin on Day 1 and covered. Then, on Day 3 the allergens are removed. The skin is clinically evaluated using visual assessment and skin palpation. The reactions are graded as negative, irritant reaction, equivocal, weak positive, strong positive, or extreme reaction at around Days 3 and 5 to capture both early and delayed reactions.¹⁷ A patch test may be positive even if obvious signs of erythema are not appreciated as expected.

ACD is more common in women, with nickel being the most frequently identified allergen.

Adjusting the lighting in the examination room, including side lighting, or using a blue background can be helpful in identifying erythema in darker skin tones.^15,16,18 Palpation of the skin also is useful, as even slight texture changes and induration are indicators of a possible skin reaction to the test allergen.¹⁵

Health disparity highlight

Clinical photographs of ACD and patch test results in patients with SOC are not commonplace in the literature. Positive patch test results in patients with darker skin tones vary from those of patients with lighter skin tones, and if the clinician reading the patch test result is not familiar with the findings in darker skin tones, the diagnosis may be delayed or missed.¹⁵

Continue to: Furthermore, Scott et al...

Furthermore, Scott et al¹⁵ highlighted that many dermatology residency training programs have a paucity of SOC education in their curriculum. This lack of representation may contribute to the diagnostic challenges encountered by health care providers.

The lower rates of patch testing in Black patients are likely due to the impact of social determinants of health.

Timely access to health care and education as well as economic stability are essential for the successful management of patients with ACD. Some individuals with SOC have been disproportionately affected by social determinants of health. Rodriguez-Homs et al¹⁹ demonstrated that the distance needed to travel to a clinic and the poverty rate of the county the patient lives in play a role in referral to a clinician specializing in contact dermatitis.

A retrospective registry review of 2310 patients undergoing patch testing at the Massachusetts General Hospital in Boston revealed that 2.5% were Black, 5.5% were Latinx, 8.3% were Asian, and the remaining 83.7% were White.²⁰ Qian et al²¹ also looked at patch testing patterns among various sociodemographic groups (N = 1,107,530) and found that 69% of patients were White and 59% were female. Rates of patch testing among patients who were Black, lesser educated, male, lower income, and younger (children ages 0-12 years) were significantly lower than for other groups when ACD was suspected (P < .0001).²¹ The lower rates of patch testing in patients with SOC may be due to low suspicion of diagnosis, low referral rates due to limited medical insurance, and financial instability, as well as other socioeconomic factors.²⁰

Tamazian et al¹⁶ reviewed pediatric populations at 13 US centers and found that Black children received patch testing less frequently than White and Hispanic children. Another review of pediatric patch testing in patients with SOC found that a less comprehensive panel of allergens was used in this population.²²

The key to resolution of ACD is removal of the offending antigen, and if patients are not being tested, then they risk having a prolonged and complicated course of ACD with a poor prognosis. Patients with SOC also experience greater negative psychosocial impact due to ACD disease burden.^21,23 The lower rates of patch testing in Black patients cannot solely be attributed to difficulty diagnosing ACD in darker skin tones; it is likely due to the impact of social determinants of health. Alleviating health disparities will improve patient outcomes and quality of life.

THE COMPARISON

A An 11-year-old Hispanic boy with allergic contact dermatitis (ACD) on the abdomen. The geometric nature of the eruption and proximity to the belt buckle were highly suggestive of ACD to nickel; patch testing was not needed.

B A Black woman with ACD on the neck. A punch biopsy demonstrated spongiotic dermatitis that was typical of ACD. The diagnosis was supported by the patient’s history of dermatitis that developed after new products were applied to the hair. The patient declined patch testing.

C A Hispanic man with ACD on hair-bearing areas on the face where hair dye was used. The patient’s history of dermatitis following the application of hair dye was highly suggestive of ACD; patch testing confirmed the allergen was paraphenylenediamine (PPD).

CT112004196_ABC.jpg

Allergic contact dermatitis (ACD) is an inflammatory condition of the skin caused by an immunologic response to one or more identifiable allergens. A delayed-type immune response (type IV hypersensitivity reaction) occurs after the skin is reexposed to an offending allergen.¹ Severe pruritus is the main symptom of ACD in the early stages, accompanied by erythema, vesicles, and scaling in a distinct pattern corresponding to the allergen’s contact with the skin.² Delayed widespread dermatitis after exposure to an allergen—a phenomenon known as autoeczematization (id reaction)—also may occur.³

The gold-standard diagnostic tool for ACD is patch testing, in which the patient is re-exposed to the suspected contact allergen(s) and observed for the development of dermatitis.⁴ However, ACD can be diagnosed with a detailed patient history including occupation, hobbies, personal care practices, and possible triggers with subsequent rashes. Thorough clinical examination of the skin is paramount. Indicators of possible ACD include dermatitis that persists despite use of appropriate treatment, an unexplained flare of previously quiescent dermatitis, and a diagnosis of dermatitis without a clear cause.¹

Hairdressers, health care workers, and metal workers are at higher risk for ACD.⁵ Occupational ACD has notable socioeconomic implications, as it can result in frequent sick days, inability to perform tasks at work, and in some cases job loss.⁶

Patients with atopic dermatitis have impaired barrier function of the skin, permitting the entrance of allergens and subsequent sensitization.⁷ Allergic contact dermatitis is a challenge to manage, as complete avoidance of the allergen may not be possible.⁸

The underrepresentation of patients with skin of color (SOC) in educational materials as well as socioeconomic health disparities may contribute to the lower rates of diagnosis, patch testing, and treatment of ACD in this patient population.

Epidemiology

An ACD prevalence of 15.2% was reported in a study of 793 Danish patients who underwent skin prick and patch testing.⁹ Alinaghi et al¹⁰ conducted a meta-analysis of 20,107 patients across 28 studies who were patch tested to determine the prevalence of ACD in the general population. The researchers concluded that 20.1% (95% CI, 16.8%- 23.7%) of the general population experienced ACD. They analyzed 22 studies to determine the prevalence of ACD based on specific geographic area including 18,709 individuals from Europe with a prevalence of 19.5% (95% CI, 15.8%-23.4%), 1639 individuals from North America with a prevalence of 20.6% (95% CI, 9.2%-35.2%), and 2 studies from China (no other studies from Asia found) with a prevalence of 20.6% (95% CI, 17.4%-23.9%). Researchers did not find data from studies conducted in Africa or South America.¹⁰

The current available epidemiologic data on ACD are not representative of SOC populations. DeLeo et al¹¹ looked at patch test reaction patterns in association with race and ethnicity in a large sample size (N=19,457); 17,803 (92.9%) of these patients were White and only 1360 (7.1%) were Black. Large-scale, inclusive studies are needed, which can only be achieved with increased suspicion for ACD and increased access to patch testing.

Allergic contact dermatitis is more common in women, with nickel being the most frequently identified allergen (Figure, A).¹⁰ Personal care products often are linked to ACD (Figure, B). An analysis of data from the North American Contact Dermatitis Group revealed that the top 5 personal care product allergens were methylisothiazolinone (a preservative), fragrance mix I, balsam of Peru, quaternium-15 (a preservative), and paraphenylenediamine (PPD)(a common component of hair dye) (Figure, C).¹²

There is a paucity of epidemiologic data among various ethnic groups; however, a few studies have suggested that there is no difference in the frequency rates of positive patch test results in Black vs White populations.^11,13,14 One study of patch test results from 114 Black patients and 877 White patients at the Cleveland Clinic Foundation in Ohio demonstrated a similar allergy frequency of 43.0% and 43.6%, respectively.¹³ However, there were differences in the types of allergen sensitization. Black patients had higher positive patch test rates for PPD than White patients (10.6% vs 4.5%). Black men had a higher frequency of sensitivity to PPD (21.2% vs 4.2%) and imidazolidinyl urea (a formaldehyde-releasing preservative) (9.1% vs 2.6%) compared to White men.¹³

Ethnicity and cultural practices influence epidemiologic patterns of ACD. Darker hair dyes used in Black patients¹⁴ and deeply pigmented PPD dye found in henna tattoos used in Indian and Black patients¹⁵ may lead to increased sensitization to PPD. Allergic contact dermatitis due to formaldehyde is more common in White patients, possibly due to more frequent use of formaldehyde-containing moisturizers, shampoos, and creams.¹⁵

Key clinical features in people with darker skin tones

In patients with SOC, the clinical features of ACD vary, posing a diagnostic challenge. Hyperpigmentation, lichenification, and induration are more likely to be seen than the papules, vesicles, and erythematous dermatitis often described in lighter skin tones or acute ACD. Erythema can be difficult to assess on darker skin and may appear violaceous or very faint pink.¹⁶

Worth noting

A high index of suspicion is necessary when interpreting patch tests in patients with SOC, as patch test kits use a reading plate with graduated intensities of erythema, papulation, and vesicular reactions to determine the likelihood of ACD. The potential contact allergens are placed on the skin on day 1 and covered. Then, on day 3 the allergens are removed. The skin is clinically evaluated using visual assessment and skin palpation. The reactions are graded as negative, irritant reaction, equivocal, weak positive, strong positive, or extreme reaction at around days 3 and 5 to capture both early and delayed reactions.¹⁷ A patch test may be positive even if obvious signs of erythema are not appreciated as expected.

Adjusting the lighting in the examination room, including side lighting, or using a blue background can be helpful in identifying erythema in darker skin tones.^15,16,18 Palpation of the skin also is useful, as even slight texture changes and induration are indicators of a possible skin reaction to the test allergen.¹⁵

Health disparity highlight

Clinical photographs of ACD and patch test results in patients with SOC are not commonplace in the literature. Positive patch test results in patients with darker skin tones vary from those of patients with lighter skin tones, and if the clinician reading the patch test result is not familiar with the findings in darker skin tones, the diagnosis may be delayed or missed.¹⁵

Furthermore, Scott et al¹⁵ highlighted that many dermatology residency training programs have a paucity of SOC education in their curriculum. This lack of representation may contribute to the diagnostic challenges encountered by health care providers.

Timely access to health care and education as well as economic stability are essential for the successful management of patients with ACD. Some individuals with SOC have been disproportionately affected by social determinants of health. Rodriguez-Homs et al¹⁹ demonstrated that the distance needed to travel to a clinic and the poverty rate of the county the patient lives in play a role in referral to a clinician specializing in contact dermatitis.

A retrospective registry review of 2310 patients undergoing patch testing at the Massachusetts General Hospital in Boston revealed that 2.5% were Black, 5.5% were Latinx, 8.3% were Asian, and the remaining 83.7% were White.²⁰ Qian et al²¹ also looked at patch testing patterns among various sociodemographic groups (N=1,107,530) and found that 69% of patients were White and 59% were female. Rates of patch testing among patients who were Black, lesser educated, male, lower income, and younger (children aged 0–12 years) were significantly lower than for other groups when ACD was suspected (P<.0001).²¹ The lower rates of patch testing in patients with SOC may be due to low suspicion of diagnosis, low referral rates due to limited medical insurance, and financial instability, as well as other socioeconomic factors.²⁰

Tamazian et al¹⁶ reviewed pediatric populations at 13 US centers and found that Black children received patch testing less frequently than White and Hispanic children. Another review of pediatric patch testing in patients with SOC found that a less comprehensive panel of allergens was used in this population.²²

The key to resolution of ACD is removal of the offending antigen, and if patients are not being tested, then they risk having a prolonged and complicated course of ACD with a poor prognosis. Patients with SOC also experience greater negative psychosocial impact due to ACD disease burden.^21,23

The lower rates of patch testing in Black patients cannot solely be attributed to difficulty diagnosing ACD in darker skin tones; it is likely due to the impact of social determinants of health. Alleviating health disparities will improve patient outcomes and quality of life.

THE COMPARISON

A An 11-year-old Hispanic boy with allergic contact dermatitis (ACD) on the abdomen. The geometric nature of the eruption and proximity to the belt buckle were highly suggestive of ACD to nickel; patch testing was not needed.

B A Black woman with ACD on the neck. A punch biopsy demonstrated spongiotic dermatitis that was typical of ACD. The diagnosis was supported by the patient’s history of dermatitis that developed after new products were applied to the hair. The patient declined patch testing.

C A Hispanic man with ACD on hair-bearing areas on the face where hair dye was used. The patient’s history of dermatitis following the application of hair dye was highly suggestive of ACD; patch testing confirmed the allergen was paraphenylenediamine (PPD).

CT112004196_ABC.jpg

Allergic contact dermatitis (ACD) is an inflammatory condition of the skin caused by an immunologic response to one or more identifiable allergens. A delayed-type immune response (type IV hypersensitivity reaction) occurs after the skin is reexposed to an offending allergen.¹ Severe pruritus is the main symptom of ACD in the early stages, accompanied by erythema, vesicles, and scaling in a distinct pattern corresponding to the allergen’s contact with the skin.² Delayed widespread dermatitis after exposure to an allergen—a phenomenon known as autoeczematization (id reaction)—also may occur.³

The gold-standard diagnostic tool for ACD is patch testing, in which the patient is re-exposed to the suspected contact allergen(s) and observed for the development of dermatitis.⁴ However, ACD can be diagnosed with a detailed patient history including occupation, hobbies, personal care practices, and possible triggers with subsequent rashes. Thorough clinical examination of the skin is paramount. Indicators of possible ACD include dermatitis that persists despite use of appropriate treatment, an unexplained flare of previously quiescent dermatitis, and a diagnosis of dermatitis without a clear cause.¹

Hairdressers, health care workers, and metal workers are at higher risk for ACD.⁵ Occupational ACD has notable socioeconomic implications, as it can result in frequent sick days, inability to perform tasks at work, and in some cases job loss.⁶

Patients with atopic dermatitis have impaired barrier function of the skin, permitting the entrance of allergens and subsequent sensitization.⁷ Allergic contact dermatitis is a challenge to manage, as complete avoidance of the allergen may not be possible.⁸

The underrepresentation of patients with skin of color (SOC) in educational materials as well as socioeconomic health disparities may contribute to the lower rates of diagnosis, patch testing, and treatment of ACD in this patient population.

Epidemiology

An ACD prevalence of 15.2% was reported in a study of 793 Danish patients who underwent skin prick and patch testing.⁹ Alinaghi et al¹⁰ conducted a meta-analysis of 20,107 patients across 28 studies who were patch tested to determine the prevalence of ACD in the general population. The researchers concluded that 20.1% (95% CI, 16.8%- 23.7%) of the general population experienced ACD. They analyzed 22 studies to determine the prevalence of ACD based on specific geographic area including 18,709 individuals from Europe with a prevalence of 19.5% (95% CI, 15.8%-23.4%), 1639 individuals from North America with a prevalence of 20.6% (95% CI, 9.2%-35.2%), and 2 studies from China (no other studies from Asia found) with a prevalence of 20.6% (95% CI, 17.4%-23.9%). Researchers did not find data from studies conducted in Africa or South America.¹⁰

The current available epidemiologic data on ACD are not representative of SOC populations. DeLeo et al¹¹ looked at patch test reaction patterns in association with race and ethnicity in a large sample size (N=19,457); 17,803 (92.9%) of these patients were White and only 1360 (7.1%) were Black. Large-scale, inclusive studies are needed, which can only be achieved with increased suspicion for ACD and increased access to patch testing.

Allergic contact dermatitis is more common in women, with nickel being the most frequently identified allergen (Figure, A).¹⁰ Personal care products often are linked to ACD (Figure, B). An analysis of data from the North American Contact Dermatitis Group revealed that the top 5 personal care product allergens were methylisothiazolinone (a preservative), fragrance mix I, balsam of Peru, quaternium-15 (a preservative), and paraphenylenediamine (PPD)(a common component of hair dye) (Figure, C).¹²

There is a paucity of epidemiologic data among various ethnic groups; however, a few studies have suggested that there is no difference in the frequency rates of positive patch test results in Black vs White populations.^11,13,14 One study of patch test results from 114 Black patients and 877 White patients at the Cleveland Clinic Foundation in Ohio demonstrated a similar allergy frequency of 43.0% and 43.6%, respectively.¹³ However, there were differences in the types of allergen sensitization. Black patients had higher positive patch test rates for PPD than White patients (10.6% vs 4.5%). Black men had a higher frequency of sensitivity to PPD (21.2% vs 4.2%) and imidazolidinyl urea (a formaldehyde-releasing preservative) (9.1% vs 2.6%) compared to White men.¹³

Ethnicity and cultural practices influence epidemiologic patterns of ACD. Darker hair dyes used in Black patients¹⁴ and deeply pigmented PPD dye found in henna tattoos used in Indian and Black patients¹⁵ may lead to increased sensitization to PPD. Allergic contact dermatitis due to formaldehyde is more common in White patients, possibly due to more frequent use of formaldehyde-containing moisturizers, shampoos, and creams.¹⁵

Key clinical features in people with darker skin tones

In patients with SOC, the clinical features of ACD vary, posing a diagnostic challenge. Hyperpigmentation, lichenification, and induration are more likely to be seen than the papules, vesicles, and erythematous dermatitis often described in lighter skin tones or acute ACD. Erythema can be difficult to assess on darker skin and may appear violaceous or very faint pink.¹⁶

Worth noting

A high index of suspicion is necessary when interpreting patch tests in patients with SOC, as patch test kits use a reading plate with graduated intensities of erythema, papulation, and vesicular reactions to determine the likelihood of ACD. The potential contact allergens are placed on the skin on day 1 and covered. Then, on day 3 the allergens are removed. The skin is clinically evaluated using visual assessment and skin palpation. The reactions are graded as negative, irritant reaction, equivocal, weak positive, strong positive, or extreme reaction at around days 3 and 5 to capture both early and delayed reactions.¹⁷ A patch test may be positive even if obvious signs of erythema are not appreciated as expected.

Adjusting the lighting in the examination room, including side lighting, or using a blue background can be helpful in identifying erythema in darker skin tones.^15,16,18 Palpation of the skin also is useful, as even slight texture changes and induration are indicators of a possible skin reaction to the test allergen.¹⁵

Health disparity highlight

Clinical photographs of ACD and patch test results in patients with SOC are not commonplace in the literature. Positive patch test results in patients with darker skin tones vary from those of patients with lighter skin tones, and if the clinician reading the patch test result is not familiar with the findings in darker skin tones, the diagnosis may be delayed or missed.¹⁵

Furthermore, Scott et al¹⁵ highlighted that many dermatology residency training programs have a paucity of SOC education in their curriculum. This lack of representation may contribute to the diagnostic challenges encountered by health care providers.

Timely access to health care and education as well as economic stability are essential for the successful management of patients with ACD. Some individuals with SOC have been disproportionately affected by social determinants of health. Rodriguez-Homs et al¹⁹ demonstrated that the distance needed to travel to a clinic and the poverty rate of the county the patient lives in play a role in referral to a clinician specializing in contact dermatitis.

A retrospective registry review of 2310 patients undergoing patch testing at the Massachusetts General Hospital in Boston revealed that 2.5% were Black, 5.5% were Latinx, 8.3% were Asian, and the remaining 83.7% were White.²⁰ Qian et al²¹ also looked at patch testing patterns among various sociodemographic groups (N=1,107,530) and found that 69% of patients were White and 59% were female. Rates of patch testing among patients who were Black, lesser educated, male, lower income, and younger (children aged 0–12 years) were significantly lower than for other groups when ACD was suspected (P<.0001).²¹ The lower rates of patch testing in patients with SOC may be due to low suspicion of diagnosis, low referral rates due to limited medical insurance, and financial instability, as well as other socioeconomic factors.²⁰

Tamazian et al¹⁶ reviewed pediatric populations at 13 US centers and found that Black children received patch testing less frequently than White and Hispanic children. Another review of pediatric patch testing in patients with SOC found that a less comprehensive panel of allergens was used in this population.²²

The key to resolution of ACD is removal of the offending antigen, and if patients are not being tested, then they risk having a prolonged and complicated course of ACD with a poor prognosis. Patients with SOC also experience greater negative psychosocial impact due to ACD disease burden.^21,23

The lower rates of patch testing in Black patients cannot solely be attributed to difficulty diagnosing ACD in darker skin tones; it is likely due to the impact of social determinants of health. Alleviating health disparities will improve patient outcomes and quality of life.

THE COMPARISON

A An 11-year-old Hispanic boy with allergic contact dermatitis (ACD) on the abdomen. The geometric nature of the eruption and proximity to the belt buckle were highly suggestive of ACD to nickel; patch testing was not needed.

B A Black woman with ACD on the neck. A punch biopsy demonstrated spongiotic dermatitis that was typical of ACD. The diagnosis was supported by the patient’s history of dermatitis that developed after new products were applied to the hair. The patient declined patch testing.

C A Hispanic man with ACD on hair-bearing areas on the face where hair dye was used. The patient’s history of dermatitis following the application of hair dye was highly suggestive of ACD; patch testing confirmed the allergen was paraphenylenediamine (PPD).

CT112004196_ABC.jpg

Allergic contact dermatitis (ACD) is an inflammatory condition of the skin caused by an immunologic response to one or more identifiable allergens. A delayed-type immune response (type IV hypersensitivity reaction) occurs after the skin is reexposed to an offending allergen.¹ Severe pruritus is the main symptom of ACD in the early stages, accompanied by erythema, vesicles, and scaling in a distinct pattern corresponding to the allergen’s contact with the skin.² Delayed widespread dermatitis after exposure to an allergen—a phenomenon known as autoeczematization (id reaction)—also may occur.³

The gold-standard diagnostic tool for ACD is patch testing, in which the patient is re-exposed to the suspected contact allergen(s) and observed for the development of dermatitis.⁴ However, ACD can be diagnosed with a detailed patient history including occupation, hobbies, personal care practices, and possible triggers with subsequent rashes. Thorough clinical examination of the skin is paramount. Indicators of possible ACD include dermatitis that persists despite use of appropriate treatment, an unexplained flare of previously quiescent dermatitis, and a diagnosis of dermatitis without a clear cause.¹

Hairdressers, health care workers, and metal workers are at higher risk for ACD.⁵ Occupational ACD has notable socioeconomic implications, as it can result in frequent sick days, inability to perform tasks at work, and in some cases job loss.⁶

Patients with atopic dermatitis have impaired barrier function of the skin, permitting the entrance of allergens and subsequent sensitization.⁷ Allergic contact dermatitis is a challenge to manage, as complete avoidance of the allergen may not be possible.⁸

The underrepresentation of patients with skin of color (SOC) in educational materials as well as socioeconomic health disparities may contribute to the lower rates of diagnosis, patch testing, and treatment of ACD in this patient population.

Epidemiology

An ACD prevalence of 15.2% was reported in a study of 793 Danish patients who underwent skin prick and patch testing.⁹ Alinaghi et al¹⁰ conducted a meta-analysis of 20,107 patients across 28 studies who were patch tested to determine the prevalence of ACD in the general population. The researchers concluded that 20.1% (95% CI, 16.8%- 23.7%) of the general population experienced ACD. They analyzed 22 studies to determine the prevalence of ACD based on specific geographic area including 18,709 individuals from Europe with a prevalence of 19.5% (95% CI, 15.8%-23.4%), 1639 individuals from North America with a prevalence of 20.6% (95% CI, 9.2%-35.2%), and 2 studies from China (no other studies from Asia found) with a prevalence of 20.6% (95% CI, 17.4%-23.9%). Researchers did not find data from studies conducted in Africa or South America.¹⁰

The current available epidemiologic data on ACD are not representative of SOC populations. DeLeo et al¹¹ looked at patch test reaction patterns in association with race and ethnicity in a large sample size (N=19,457); 17,803 (92.9%) of these patients were White and only 1360 (7.1%) were Black. Large-scale, inclusive studies are needed, which can only be achieved with increased suspicion for ACD and increased access to patch testing.

Allergic contact dermatitis is more common in women, with nickel being the most frequently identified allergen (Figure, A).¹⁰ Personal care products often are linked to ACD (Figure, B). An analysis of data from the North American Contact Dermatitis Group revealed that the top 5 personal care product allergens were methylisothiazolinone (a preservative), fragrance mix I, balsam of Peru, quaternium-15 (a preservative), and paraphenylenediamine (PPD)(a common component of hair dye) (Figure, C).¹²

There is a paucity of epidemiologic data among various ethnic groups; however, a few studies have suggested that there is no difference in the frequency rates of positive patch test results in Black vs White populations.^11,13,14 One study of patch test results from 114 Black patients and 877 White patients at the Cleveland Clinic Foundation in Ohio demonstrated a similar allergy frequency of 43.0% and 43.6%, respectively.¹³ However, there were differences in the types of allergen sensitization. Black patients had higher positive patch test rates for PPD than White patients (10.6% vs 4.5%). Black men had a higher frequency of sensitivity to PPD (21.2% vs 4.2%) and imidazolidinyl urea (a formaldehyde-releasing preservative) (9.1% vs 2.6%) compared to White men.¹³

Ethnicity and cultural practices influence epidemiologic patterns of ACD. Darker hair dyes used in Black patients¹⁴ and deeply pigmented PPD dye found in henna tattoos used in Indian and Black patients¹⁵ may lead to increased sensitization to PPD. Allergic contact dermatitis due to formaldehyde is more common in White patients, possibly due to more frequent use of formaldehyde-containing moisturizers, shampoos, and creams.¹⁵

Key clinical features in people with darker skin tones

In patients with SOC, the clinical features of ACD vary, posing a diagnostic challenge. Hyperpigmentation, lichenification, and induration are more likely to be seen than the papules, vesicles, and erythematous dermatitis often described in lighter skin tones or acute ACD. Erythema can be difficult to assess on darker skin and may appear violaceous or very faint pink.¹⁶

Worth noting

A high index of suspicion is necessary when interpreting patch tests in patients with SOC, as patch test kits use a reading plate with graduated intensities of erythema, papulation, and vesicular reactions to determine the likelihood of ACD. The potential contact allergens are placed on the skin on day 1 and covered. Then, on day 3 the allergens are removed. The skin is clinically evaluated using visual assessment and skin palpation. The reactions are graded as negative, irritant reaction, equivocal, weak positive, strong positive, or extreme reaction at around days 3 and 5 to capture both early and delayed reactions.¹⁷ A patch test may be positive even if obvious signs of erythema are not appreciated as expected.

Adjusting the lighting in the examination room, including side lighting, or using a blue background can be helpful in identifying erythema in darker skin tones.^15,16,18 Palpation of the skin also is useful, as even slight texture changes and induration are indicators of a possible skin reaction to the test allergen.¹⁵

Health disparity highlight

Clinical photographs of ACD and patch test results in patients with SOC are not commonplace in the literature. Positive patch test results in patients with darker skin tones vary from those of patients with lighter skin tones, and if the clinician reading the patch test result is not familiar with the findings in darker skin tones, the diagnosis may be delayed or missed.¹⁵

Furthermore, Scott et al¹⁵ highlighted that many dermatology residency training programs have a paucity of SOC education in their curriculum. This lack of representation may contribute to the diagnostic challenges encountered by health care providers.

Timely access to health care and education as well as economic stability are essential for the successful management of patients with ACD. Some individuals with SOC have been disproportionately affected by social determinants of health. Rodriguez-Homs et al¹⁹ demonstrated that the distance needed to travel to a clinic and the poverty rate of the county the patient lives in play a role in referral to a clinician specializing in contact dermatitis.

A retrospective registry review of 2310 patients undergoing patch testing at the Massachusetts General Hospital in Boston revealed that 2.5% were Black, 5.5% were Latinx, 8.3% were Asian, and the remaining 83.7% were White.²⁰ Qian et al²¹ also looked at patch testing patterns among various sociodemographic groups (N=1,107,530) and found that 69% of patients were White and 59% were female. Rates of patch testing among patients who were Black, lesser educated, male, lower income, and younger (children aged 0–12 years) were significantly lower than for other groups when ACD was suspected (P<.0001).²¹ The lower rates of patch testing in patients with SOC may be due to low suspicion of diagnosis, low referral rates due to limited medical insurance, and financial instability, as well as other socioeconomic factors.²⁰

Tamazian et al¹⁶ reviewed pediatric populations at 13 US centers and found that Black children received patch testing less frequently than White and Hispanic children. Another review of pediatric patch testing in patients with SOC found that a less comprehensive panel of allergens was used in this population.²²

The key to resolution of ACD is removal of the offending antigen, and if patients are not being tested, then they risk having a prolonged and complicated course of ACD with a poor prognosis. Patients with SOC also experience greater negative psychosocial impact due to ACD disease burden.^21,23

The lower rates of patch testing in Black patients cannot solely be attributed to difficulty diagnosing ACD in darker skin tones; it is likely due to the impact of social determinants of health. Alleviating health disparities will improve patient outcomes and quality of life.

THE COMPARISON

A A 51-year-old Hispanic man with a squamous cell carcinoma (SCC) of the keratoacanthoma type on the arm.

B A 75-year-old Black man with an SCC of the keratoacanthoma type on the abdomen.

C An African woman with an SCC on the lower lip decades after a large facial burn, which is known as a Marjolin ulcer.

Cutaneous squamous cell carcinoma (SCC) develops from a malignant tumor of the keratinocytes, eccrine glands, or pilosebaceous units that invades the dermis. Risk factors include lighter skin tone, higher cumulative sun exposure, human papillomavirus (HPV) infection, hidradenitis suppurativa (HS), lichen sclerosus, family history of skin cancer,1 and immunosuppression.² It typically affects sun-exposed areas of the body such as the face, scalp, neck, and extensor surfaces of the arms (Figure, A).^3,4 However, in those with darker skin tones, the most common anatomic sites are those that are not exposed to the sun (Figure, B). Squamous cell carcinoma is diagnosed via skin biopsy. Treatment options include surgical excision, destructive methods such as electrodesiccation and curettage, and Mohs micrographic surgery. Cutaneous SCC has a cure rate of more than 95% and a mortality rate of 1.5% to 2% in the United States.³

CT112002097_Fig_ABC.jpg

Epidemiology

Squamous cell carcinoma is the most common skin cancer occurring in Black individuals, manifesting primarily in the fifth decade of life.^5-7 It is the second most common skin cancer in White, Hispanic, and Asian individuals and is more common in males.⁸ In a study of organ transplant recipients (N=413), Pritchett et al⁹ reported that HPV infection was a major risk factor in Hispanic patients because 66.7% of those with SCC had a history of HPV. However, HPV is a risk factor for SCC in all ethnic groups.¹⁰

Key clinical features in people with darker skin tones

Anatomic location

• The lower legs and anogenital areas are the most common sites for SCC in patients with skin of color.^4,11
• In Black women, SCC occurs more often on sun-exposed areas such as the arms and legs compared to Black men.^7,12-14
• The genitalia, perianal area, ocular mucosa, and oral mucosa are the least likely areas to be routinely examined, even in skin cancer clinics that see high-risk patients, despite the SCC risk in the anogenital area.^15,16
• Squamous cell carcinoma of the lips and scalp is more likely to occur in Black women vs Black men.^4,7,17 Clinical appearance
• In those with darker skin tones, SCCs may appear hyperpigmented4 or hyperkeratotic with a lack of erythema and an inconsistent appearance.^6,7,18
• A nonhealing ulceration of the skin should prompt a biopsy to rule out SCC.^3,19

Worth noting

In patients with darker skin tones, the risk for SCC increases in areas with chronic inflammation and scarring of the skin.^{4,6,7,11,18,20-22} In Black patients, 20% to 40% of cases of SCC occur in the setting of chronic inflammation and scarring.^6,7,18 Chronic inflammatory conditions include ulcers, lupus vulgaris, discoid lupus erythematosus, and HPV. In patients with discoid lupus erythematosus, there is an additive effect of sun exposure on the scars, which may play a role in the pathogenesis and metastasis risk for skin cancer in Black patients.⁴ Other scarring conditions include thermal or chemical burn scars, areas of physical trauma, and prior sites of radiation treatment.^14,23 Squamous cell carcinoma arising in a burn scar is called a Marjolin ulcer or malignant degeneration of a scar (Figure, C). It is reported more often in lower-income, underresourced countries, which may suggest the need for early detection in populations with skin of color.²⁴

Squamous cell carcinoma is more aggressive in sites that are not exposed to sun compared to sun-exposed areas.^17,25

The risk for SCC is increased in immunocompromised patients,² especially those with HPV.¹⁰

The prevalence of SCC in those with HS is approximately 4.6%. The chronic inflammation and irritation from HS in association with other risk factors such as tobacco use may contribute to the malignant transformation to SCC.²⁶

Health disparity highlight

• The risk for metastasis from SCC is 20% to 40% in Black patients vs 1% to 4% in White patients.^4,6,27
• Penile SCC was associated with a lower overall survival rate in patients of African descent.^20,21
• The increased morbidity and mortality from SCC in patients with skin of color may be attributed to delays in diagnosis and treatment as well as an incomplete understanding of tumor genetics.^4,6,18

Acknowledgment—The authors thank Elyse Gadra (Philadelphia, Pennsylvania) for assistance in the preparation of this manuscript.

THE COMPARISON

A A 51-year-old Hispanic man with a squamous cell carcinoma (SCC) of the keratoacanthoma type on the arm.

B A 75-year-old Black man with an SCC of the keratoacanthoma type on the abdomen.

C An African woman with an SCC on the lower lip decades after a large facial burn, which is known as a Marjolin ulcer.

Cutaneous squamous cell carcinoma (SCC) develops from a malignant tumor of the keratinocytes, eccrine glands, or pilosebaceous units that invades the dermis. Risk factors include lighter skin tone, higher cumulative sun exposure, human papillomavirus (HPV) infection, hidradenitis suppurativa (HS), lichen sclerosus, family history of skin cancer,1 and immunosuppression.² It typically affects sun-exposed areas of the body such as the face, scalp, neck, and extensor surfaces of the arms (Figure, A).^3,4 However, in those with darker skin tones, the most common anatomic sites are those that are not exposed to the sun (Figure, B). Squamous cell carcinoma is diagnosed via skin biopsy. Treatment options include surgical excision, destructive methods such as electrodesiccation and curettage, and Mohs micrographic surgery. Cutaneous SCC has a cure rate of more than 95% and a mortality rate of 1.5% to 2% in the United States.³

CT112002097_Fig_ABC.jpg

Epidemiology

Squamous cell carcinoma is the most common skin cancer occurring in Black individuals, manifesting primarily in the fifth decade of life.^5-7 It is the second most common skin cancer in White, Hispanic, and Asian individuals and is more common in males.⁸ In a study of organ transplant recipients (N=413), Pritchett et al⁹ reported that HPV infection was a major risk factor in Hispanic patients because 66.7% of those with SCC had a history of HPV. However, HPV is a risk factor for SCC in all ethnic groups.¹⁰

Key clinical features in people with darker skin tones

Anatomic location

• The lower legs and anogenital areas are the most common sites for SCC in patients with skin of color.^4,11
• In Black women, SCC occurs more often on sun-exposed areas such as the arms and legs compared to Black men.^7,12-14
• The genitalia, perianal area, ocular mucosa, and oral mucosa are the least likely areas to be routinely examined, even in skin cancer clinics that see high-risk patients, despite the SCC risk in the anogenital area.^15,16
• Squamous cell carcinoma of the lips and scalp is more likely to occur in Black women vs Black men.^4,7,17 Clinical appearance
• In those with darker skin tones, SCCs may appear hyperpigmented4 or hyperkeratotic with a lack of erythema and an inconsistent appearance.^6,7,18
• A nonhealing ulceration of the skin should prompt a biopsy to rule out SCC.^3,19

Worth noting

In patients with darker skin tones, the risk for SCC increases in areas with chronic inflammation and scarring of the skin.^{4,6,7,11,18,20-22} In Black patients, 20% to 40% of cases of SCC occur in the setting of chronic inflammation and scarring.^6,7,18 Chronic inflammatory conditions include ulcers, lupus vulgaris, discoid lupus erythematosus, and HPV. In patients with discoid lupus erythematosus, there is an additive effect of sun exposure on the scars, which may play a role in the pathogenesis and metastasis risk for skin cancer in Black patients.⁴ Other scarring conditions include thermal or chemical burn scars, areas of physical trauma, and prior sites of radiation treatment.^14,23 Squamous cell carcinoma arising in a burn scar is called a Marjolin ulcer or malignant degeneration of a scar (Figure, C). It is reported more often in lower-income, underresourced countries, which may suggest the need for early detection in populations with skin of color.²⁴

Squamous cell carcinoma is more aggressive in sites that are not exposed to sun compared to sun-exposed areas.^17,25

The risk for SCC is increased in immunocompromised patients,² especially those with HPV.¹⁰

The prevalence of SCC in those with HS is approximately 4.6%. The chronic inflammation and irritation from HS in association with other risk factors such as tobacco use may contribute to the malignant transformation to SCC.²⁶

Health disparity highlight

• The risk for metastasis from SCC is 20% to 40% in Black patients vs 1% to 4% in White patients.^4,6,27
• Penile SCC was associated with a lower overall survival rate in patients of African descent.^20,21
• The increased morbidity and mortality from SCC in patients with skin of color may be attributed to delays in diagnosis and treatment as well as an incomplete understanding of tumor genetics.^4,6,18

Acknowledgment—The authors thank Elyse Gadra (Philadelphia, Pennsylvania) for assistance in the preparation of this manuscript.

THE COMPARISON

A A 51-year-old Hispanic man with a squamous cell carcinoma (SCC) of the keratoacanthoma type on the arm.

B A 75-year-old Black man with an SCC of the keratoacanthoma type on the abdomen.

C An African woman with an SCC on the lower lip decades after a large facial burn, which is known as a Marjolin ulcer.

Cutaneous squamous cell carcinoma (SCC) develops from a malignant tumor of the keratinocytes, eccrine glands, or pilosebaceous units that invades the dermis. Risk factors include lighter skin tone, higher cumulative sun exposure, human papillomavirus (HPV) infection, hidradenitis suppurativa (HS), lichen sclerosus, family history of skin cancer,1 and immunosuppression.² It typically affects sun-exposed areas of the body such as the face, scalp, neck, and extensor surfaces of the arms (Figure, A).^3,4 However, in those with darker skin tones, the most common anatomic sites are those that are not exposed to the sun (Figure, B). Squamous cell carcinoma is diagnosed via skin biopsy. Treatment options include surgical excision, destructive methods such as electrodesiccation and curettage, and Mohs micrographic surgery. Cutaneous SCC has a cure rate of more than 95% and a mortality rate of 1.5% to 2% in the United States.³

CT112002097_Fig_ABC.jpg

Epidemiology

Squamous cell carcinoma is the most common skin cancer occurring in Black individuals, manifesting primarily in the fifth decade of life.^5-7 It is the second most common skin cancer in White, Hispanic, and Asian individuals and is more common in males.⁸ In a study of organ transplant recipients (N=413), Pritchett et al⁹ reported that HPV infection was a major risk factor in Hispanic patients because 66.7% of those with SCC had a history of HPV. However, HPV is a risk factor for SCC in all ethnic groups.¹⁰

Key clinical features in people with darker skin tones

Anatomic location

• The lower legs and anogenital areas are the most common sites for SCC in patients with skin of color.^4,11
• In Black women, SCC occurs more often on sun-exposed areas such as the arms and legs compared to Black men.^7,12-14
• The genitalia, perianal area, ocular mucosa, and oral mucosa are the least likely areas to be routinely examined, even in skin cancer clinics that see high-risk patients, despite the SCC risk in the anogenital area.^15,16
• Squamous cell carcinoma of the lips and scalp is more likely to occur in Black women vs Black men.^4,7,17 Clinical appearance
• In those with darker skin tones, SCCs may appear hyperpigmented4 or hyperkeratotic with a lack of erythema and an inconsistent appearance.^6,7,18
• A nonhealing ulceration of the skin should prompt a biopsy to rule out SCC.^3,19

Worth noting

In patients with darker skin tones, the risk for SCC increases in areas with chronic inflammation and scarring of the skin.^{4,6,7,11,18,20-22} In Black patients, 20% to 40% of cases of SCC occur in the setting of chronic inflammation and scarring.^6,7,18 Chronic inflammatory conditions include ulcers, lupus vulgaris, discoid lupus erythematosus, and HPV. In patients with discoid lupus erythematosus, there is an additive effect of sun exposure on the scars, which may play a role in the pathogenesis and metastasis risk for skin cancer in Black patients.⁴ Other scarring conditions include thermal or chemical burn scars, areas of physical trauma, and prior sites of radiation treatment.^14,23 Squamous cell carcinoma arising in a burn scar is called a Marjolin ulcer or malignant degeneration of a scar (Figure, C). It is reported more often in lower-income, underresourced countries, which may suggest the need for early detection in populations with skin of color.²⁴

Squamous cell carcinoma is more aggressive in sites that are not exposed to sun compared to sun-exposed areas.^17,25

The risk for SCC is increased in immunocompromised patients,² especially those with HPV.¹⁰

The prevalence of SCC in those with HS is approximately 4.6%. The chronic inflammation and irritation from HS in association with other risk factors such as tobacco use may contribute to the malignant transformation to SCC.²⁶

Health disparity highlight

• The risk for metastasis from SCC is 20% to 40% in Black patients vs 1% to 4% in White patients.^4,6,27
• Penile SCC was associated with a lower overall survival rate in patients of African descent.^20,21
• The increased morbidity and mortality from SCC in patients with skin of color may be attributed to delays in diagnosis and treatment as well as an incomplete understanding of tumor genetics.^4,6,18

Acknowledgment—The authors thank Elyse Gadra (Philadelphia, Pennsylvania) for assistance in the preparation of this manuscript.

THE COMPARISON

A A 51-year-old Hispanic man with a squamous cell carcinoma (SCC) of the keratoacanthoma type on the arm.

B A 75-year-old Black man with an SCC of the keratoacanthoma type on the abdomen.

C An African woman with an SCC on the lower lip decades after a large facial burn, which is known as a Marjolin ulcer.

Cutaneous squamous cell carcinoma (SCC) develops from a malignant tumor of the keratinocytes, eccrine glands, or pilosebaceous units that invades the dermis. Risk factors include lighter skin tone, higher cumulative sun exposure, human papillomavirus (HPV) infection, hidradenitis suppurativa (HS), lichen sclerosus, family history of skin cancer,¹ and immunosuppression.² It typically affects sun-exposed areas of the body such as the face, scalp, neck, and extensor surfaces of the arms (FIGURE A).^3,4 However, in those with darker skin tones, the most common anatomic sites are those that are not exposed to the sun (FIGURE B). SCC is diagnosed via skin biopsy. Treatment options include surgical excision, destructive methods such as electrodesiccation and curettage, and Mohs micrographic surgery. Cutaneous SCC has a cure rate of more than 95% and a mortality rate of 1.5% to 2% in the United States.³

JFP07207e18_f1.jpg

Epidemiology

SCC is the most common skin cancer occurring in Black individuals, manifesting primarily in the fifth decade of life.^5-7 It is the second most common skin cancer in White, Hispanic, and Asian individuals and is more common in males.⁸ In a study of organ transplant recipients (N = 413), Pritchett et al⁹ reported that HPV infection was a major risk factor in Hispanic patients because 66.7% of those with SCC had a history of HPV. However, HPV is a risk factor for SCC in all ethnic groups.¹⁰

Key clinical features in people with darker skin tones

Anatomic location

• The lower legs and anogenital areas are the most common sites for SCC in patients with skin of color.^4,11
• In Black women, SCC occurs more often on sun-exposed areas such as the arms and legs compared to Black men.^7,12-14
• The genitalia, perianal area, ocular mucosa, and oral mucosa are the least likely areas to be routinely examined, even in skin cancer clinics that see highrisk patients, despite the SCC risk in the anogenital area.^15,16
• Squamous cell carcinoma of the lips and scalp is more likely to occur in Black women vs Black men.^4,7,17

Clinical appearance

• In those with darker skin tones, SCCs may appear hyperpigmented4 or hyperkeratotic with a lack of erythema and an inconsistent appearance.^6,7,18
• A nonhealing ulceration of the skin should prompt a biopsy to rule out SCC.^3,19

Worth noting

In patients with darker skin tones, the risk for SCC increases in areas with chronic inflammation and scarring of the skin.^{4,6,7,11,18,20-22} In Black patients, 20% to 40% of cases of SCC occur in the setting of chronic inflammation and scarring.^6,7,18 Chronic inflammatory conditions include ulcers, lupus vulgaris, discoid lupus erythematosus, and HPV. In patients with discoid lupus erythematosus, there is an additive effect of sun exposure on the scars, which may play a role in the pathogenesis and metastasis risk for skin cancer in Black patients.⁴ Other scarring conditions include thermal or chemical burn scars, areas of physical trauma, and prior sites of radiation treatment.^14,23 SCC arising in a burn scar is called a Marjolin ulcer or malignant degeneration of a scar (FIGURE C). It is reported more often in lower-income, underresourced countries, which may suggest the need for early detection in populations with skin of color.²⁴

SCC is more aggressive in sites that are not exposed to sun compared to sun-exposed areas.^17,25

Continue to: The risk for SCC...

The risk for SCC is increased in immunocompromised patients,2 especially those with HPV.¹⁰

The prevalence of SCC in those with HS is approximately 4.6%. The chronic inflammation and irritation from HS in association with other risk factors such as tobacco use may contribute to the malignant transformation to SCC.²⁶

Health disparity highlight

• The risk for metastasis from SCC is 20% to 40% in Black patients vs 1% to 4% in White patients.^4,6,27
• Penile SCC was associated with a lower overall survival rate in patients of African descent.^20,21
• The increased morbidity and mortality from SCC in patients with skin of color may be attributed to delays in diagnosis and treatment as well as an incomplete understanding of tumor genetics.^4,6,18

ACKNOWLEDGMENT
The authors thank Elyse Gadra (Philadelphia, Pennsylvania) for assistance in the preparation of this manuscript.

THE COMPARISON

A A 51-year-old Hispanic man with a squamous cell carcinoma (SCC) of the keratoacanthoma type on the arm.

B A 75-year-old Black man with an SCC of the keratoacanthoma type on the abdomen.

C An African woman with an SCC on the lower lip decades after a large facial burn, which is known as a Marjolin ulcer.

Cutaneous squamous cell carcinoma (SCC) develops from a malignant tumor of the keratinocytes, eccrine glands, or pilosebaceous units that invades the dermis. Risk factors include lighter skin tone, higher cumulative sun exposure, human papillomavirus (HPV) infection, hidradenitis suppurativa (HS), lichen sclerosus, family history of skin cancer,¹ and immunosuppression.² It typically affects sun-exposed areas of the body such as the face, scalp, neck, and extensor surfaces of the arms (FIGURE A).^3,4 However, in those with darker skin tones, the most common anatomic sites are those that are not exposed to the sun (FIGURE B). SCC is diagnosed via skin biopsy. Treatment options include surgical excision, destructive methods such as electrodesiccation and curettage, and Mohs micrographic surgery. Cutaneous SCC has a cure rate of more than 95% and a mortality rate of 1.5% to 2% in the United States.³

JFP07207e18_f1.jpg

Epidemiology

SCC is the most common skin cancer occurring in Black individuals, manifesting primarily in the fifth decade of life.^5-7 It is the second most common skin cancer in White, Hispanic, and Asian individuals and is more common in males.⁸ In a study of organ transplant recipients (N = 413), Pritchett et al⁹ reported that HPV infection was a major risk factor in Hispanic patients because 66.7% of those with SCC had a history of HPV. However, HPV is a risk factor for SCC in all ethnic groups.¹⁰

Key clinical features in people with darker skin tones

Anatomic location

• The lower legs and anogenital areas are the most common sites for SCC in patients with skin of color.^4,11
• In Black women, SCC occurs more often on sun-exposed areas such as the arms and legs compared to Black men.^7,12-14
• The genitalia, perianal area, ocular mucosa, and oral mucosa are the least likely areas to be routinely examined, even in skin cancer clinics that see highrisk patients, despite the SCC risk in the anogenital area.^15,16
• Squamous cell carcinoma of the lips and scalp is more likely to occur in Black women vs Black men.^4,7,17

Clinical appearance

• In those with darker skin tones, SCCs may appear hyperpigmented4 or hyperkeratotic with a lack of erythema and an inconsistent appearance.^6,7,18
• A nonhealing ulceration of the skin should prompt a biopsy to rule out SCC.^3,19

Worth noting

In patients with darker skin tones, the risk for SCC increases in areas with chronic inflammation and scarring of the skin.^{4,6,7,11,18,20-22} In Black patients, 20% to 40% of cases of SCC occur in the setting of chronic inflammation and scarring.^6,7,18 Chronic inflammatory conditions include ulcers, lupus vulgaris, discoid lupus erythematosus, and HPV. In patients with discoid lupus erythematosus, there is an additive effect of sun exposure on the scars, which may play a role in the pathogenesis and metastasis risk for skin cancer in Black patients.⁴ Other scarring conditions include thermal or chemical burn scars, areas of physical trauma, and prior sites of radiation treatment.^14,23 SCC arising in a burn scar is called a Marjolin ulcer or malignant degeneration of a scar (FIGURE C). It is reported more often in lower-income, underresourced countries, which may suggest the need for early detection in populations with skin of color.²⁴

SCC is more aggressive in sites that are not exposed to sun compared to sun-exposed areas.^17,25

Continue to: The risk for SCC...

The risk for SCC is increased in immunocompromised patients,2 especially those with HPV.¹⁰

The prevalence of SCC in those with HS is approximately 4.6%. The chronic inflammation and irritation from HS in association with other risk factors such as tobacco use may contribute to the malignant transformation to SCC.²⁶

Health disparity highlight

• The risk for metastasis from SCC is 20% to 40% in Black patients vs 1% to 4% in White patients.^4,6,27
• Penile SCC was associated with a lower overall survival rate in patients of African descent.^20,21
• The increased morbidity and mortality from SCC in patients with skin of color may be attributed to delays in diagnosis and treatment as well as an incomplete understanding of tumor genetics.^4,6,18

ACKNOWLEDGMENT
The authors thank Elyse Gadra (Philadelphia, Pennsylvania) for assistance in the preparation of this manuscript.

THE COMPARISON

A A 51-year-old Hispanic man with a squamous cell carcinoma (SCC) of the keratoacanthoma type on the arm.

B A 75-year-old Black man with an SCC of the keratoacanthoma type on the abdomen.

C An African woman with an SCC on the lower lip decades after a large facial burn, which is known as a Marjolin ulcer.

Cutaneous squamous cell carcinoma (SCC) develops from a malignant tumor of the keratinocytes, eccrine glands, or pilosebaceous units that invades the dermis. Risk factors include lighter skin tone, higher cumulative sun exposure, human papillomavirus (HPV) infection, hidradenitis suppurativa (HS), lichen sclerosus, family history of skin cancer,¹ and immunosuppression.² It typically affects sun-exposed areas of the body such as the face, scalp, neck, and extensor surfaces of the arms (FIGURE A).^3,4 However, in those with darker skin tones, the most common anatomic sites are those that are not exposed to the sun (FIGURE B). SCC is diagnosed via skin biopsy. Treatment options include surgical excision, destructive methods such as electrodesiccation and curettage, and Mohs micrographic surgery. Cutaneous SCC has a cure rate of more than 95% and a mortality rate of 1.5% to 2% in the United States.³

JFP07207e18_f1.jpg

Epidemiology

SCC is the most common skin cancer occurring in Black individuals, manifesting primarily in the fifth decade of life.^5-7 It is the second most common skin cancer in White, Hispanic, and Asian individuals and is more common in males.⁸ In a study of organ transplant recipients (N = 413), Pritchett et al⁹ reported that HPV infection was a major risk factor in Hispanic patients because 66.7% of those with SCC had a history of HPV. However, HPV is a risk factor for SCC in all ethnic groups.¹⁰

Key clinical features in people with darker skin tones

Anatomic location

• The lower legs and anogenital areas are the most common sites for SCC in patients with skin of color.^4,11
• In Black women, SCC occurs more often on sun-exposed areas such as the arms and legs compared to Black men.^7,12-14
• The genitalia, perianal area, ocular mucosa, and oral mucosa are the least likely areas to be routinely examined, even in skin cancer clinics that see highrisk patients, despite the SCC risk in the anogenital area.^15,16
• Squamous cell carcinoma of the lips and scalp is more likely to occur in Black women vs Black men.^4,7,17

Clinical appearance

• In those with darker skin tones, SCCs may appear hyperpigmented4 or hyperkeratotic with a lack of erythema and an inconsistent appearance.^6,7,18
• A nonhealing ulceration of the skin should prompt a biopsy to rule out SCC.^3,19

Worth noting

In patients with darker skin tones, the risk for SCC increases in areas with chronic inflammation and scarring of the skin.^{4,6,7,11,18,20-22} In Black patients, 20% to 40% of cases of SCC occur in the setting of chronic inflammation and scarring.^6,7,18 Chronic inflammatory conditions include ulcers, lupus vulgaris, discoid lupus erythematosus, and HPV. In patients with discoid lupus erythematosus, there is an additive effect of sun exposure on the scars, which may play a role in the pathogenesis and metastasis risk for skin cancer in Black patients.⁴ Other scarring conditions include thermal or chemical burn scars, areas of physical trauma, and prior sites of radiation treatment.^14,23 SCC arising in a burn scar is called a Marjolin ulcer or malignant degeneration of a scar (FIGURE C). It is reported more often in lower-income, underresourced countries, which may suggest the need for early detection in populations with skin of color.²⁴

SCC is more aggressive in sites that are not exposed to sun compared to sun-exposed areas.^17,25

Continue to: The risk for SCC...

The risk for SCC is increased in immunocompromised patients,2 especially those with HPV.¹⁰

The prevalence of SCC in those with HS is approximately 4.6%. The chronic inflammation and irritation from HS in association with other risk factors such as tobacco use may contribute to the malignant transformation to SCC.²⁶

Health disparity highlight

• The risk for metastasis from SCC is 20% to 40% in Black patients vs 1% to 4% in White patients.^4,6,27
• Penile SCC was associated with a lower overall survival rate in patients of African descent.^20,21
• The increased morbidity and mortality from SCC in patients with skin of color may be attributed to delays in diagnosis and treatment as well as an incomplete understanding of tumor genetics.^4,6,18

ACKNOWLEDGMENT
The authors thank Elyse Gadra (Philadelphia, Pennsylvania) for assistance in the preparation of this manuscript.

THE COMPARISON

A A 23-year-old White woman with malar erythema from acute cutaneous lupus erythematosus. The erythema also can be seen on the nose and eyelids but spares the nasolabial folds.

B A Black woman with malar erythema and hyperpigmentation from acute cutaneous lupus erythematosus. The nasolabial folds are spared.

C A 19-year-old Latina woman with malar erythema from acute cutaneous lupus erythematosus. The erythema also can be seen on the nose, chin, and eyelids but spares the nasolabial folds. Cutaneous erosions are present on the right cheek as part of the lupus flare.

JFP07206e1_f1.jpg

Systemic lupus erythematosus (SLE) is a chronic autoimmune condition that affects the kidneys, lungs, brain, and heart, although it is not limited to these organs. Dermatologists and primary care physicians play a critical role in the early identification of SLE (particularly in those with skin of color), as the standardized mortality rate is 2.6-fold higher in patients with SLE compared to the general population.¹ The clinical manifestations of SLE vary.

Epidemiology

A meta-analysis of data from the Centers for Disease Control and Prevention National Lupus Registry network including 5417 patients revealed a prevalence of 72.8 cases per 100,000 person-years.² The prevalence was higher in females than males and highest among females identifying as Black. White and Asian/ Pacific Islander females had the lowest prevalence. The American Indian (indigenous)/Alaska Native–identifying population had the highest race-specific SLE estimates among both females and males compared to other racial/ethnic groups.²

Key clinical features in people with darker skin tones

The diagnosis of SLE is based on clinical and immunologic criteria from the European League Against Rheumatism/American College of Rheumatology.^3,4 An antinuclear antibody titer of 1:80 or higher at least once is required for the diagnosis of SLE, as long as there is not another more likely diagnosis. If it is present, 22 additive weighted classification criteria are considered; each criterion is assigned points, ranging from 2 to 10. Patients with at least 1 clinical criterion and 10 or more points are classified as having SLE. If more than 1 of the criteria are met in a domain, then the one with the highest numerical value is counted.^3,4

Aringer et al^3,4 outline the criteria and numerical points to make the diagnosis of SLE. The mucocutaneous component of the SLE diagnostic criteria^3,4 includes nonscarring alopecia, oral ulcers, subacute cutaneous or discoid lupus erythematosus,⁵ and acute cutaneous lupus erythematosus, with acute cutaneous lupus erythematosus being the highest-weighted criterion in that domain. The other clinical domains are constitutional, hematologic, neuropsychiatric, serosal, musculoskeletal, renal, antiphospholipid antibodies, complement proteins, and SLE-specific antibodies.^3,4

The malar (“butterfly”) rash of SLE characteristically includes erythema that spares the nasolabial folds but affects the nasal bridge and cheeks.⁶ The rash occasionally may be pruritic and painful, lasting days to weeks. Photosensitivity occurs, resulting in rashes or even an overall worsening of SLE symptoms. In those with darker skin tones, erythema may appear violaceous or may not be as readily appreciated.⁶

Worth noting

• Patients with skin of color are at an increased risk for postinflammatory hypopigmentation and hyperpigmentation (pigment alteration), hypertrophic scars, and keloids.^7,8
• The mortality rate for those with SLE is high despite early recognition and treatment when compared to the general population.^1,9

Health disparity highlight

Those at greatest risk for death from SLE in the United States are those of African descent, Hispanic individuals, men, and those with low socioeconomic status,⁹ which likely is primarily driven by social determinants of health instead of genetic patterns. Income level, educational attainment, insurance status, and environmental factors¹⁰ have farreaching effects, negatively impacting quality of life and even mortality.

THE COMPARISON

A A 23-year-old White woman with malar erythema from acute cutaneous lupus erythematosus. The erythema also can be seen on the nose and eyelids but spares the nasolabial folds.

B A Black woman with malar erythema and hyperpigmentation from acute cutaneous lupus erythematosus. The nasolabial folds are spared.

C A 19-year-old Latina woman with malar erythema from acute cutaneous lupus erythematosus. The erythema also can be seen on the nose, chin, and eyelids but spares the nasolabial folds. Cutaneous erosions are present on the right cheek as part of the lupus flare.

JFP07206e1_f1.jpg

Systemic lupus erythematosus (SLE) is a chronic autoimmune condition that affects the kidneys, lungs, brain, and heart, although it is not limited to these organs. Dermatologists and primary care physicians play a critical role in the early identification of SLE (particularly in those with skin of color), as the standardized mortality rate is 2.6-fold higher in patients with SLE compared to the general population.¹ The clinical manifestations of SLE vary.

Epidemiology

A meta-analysis of data from the Centers for Disease Control and Prevention National Lupus Registry network including 5417 patients revealed a prevalence of 72.8 cases per 100,000 person-years.² The prevalence was higher in females than males and highest among females identifying as Black. White and Asian/ Pacific Islander females had the lowest prevalence. The American Indian (indigenous)/Alaska Native–identifying population had the highest race-specific SLE estimates among both females and males compared to other racial/ethnic groups.²

Key clinical features in people with darker skin tones

The diagnosis of SLE is based on clinical and immunologic criteria from the European League Against Rheumatism/American College of Rheumatology.^3,4 An antinuclear antibody titer of 1:80 or higher at least once is required for the diagnosis of SLE, as long as there is not another more likely diagnosis. If it is present, 22 additive weighted classification criteria are considered; each criterion is assigned points, ranging from 2 to 10. Patients with at least 1 clinical criterion and 10 or more points are classified as having SLE. If more than 1 of the criteria are met in a domain, then the one with the highest numerical value is counted.^3,4

Aringer et al^3,4 outline the criteria and numerical points to make the diagnosis of SLE. The mucocutaneous component of the SLE diagnostic criteria^3,4 includes nonscarring alopecia, oral ulcers, subacute cutaneous or discoid lupus erythematosus,⁵ and acute cutaneous lupus erythematosus, with acute cutaneous lupus erythematosus being the highest-weighted criterion in that domain. The other clinical domains are constitutional, hematologic, neuropsychiatric, serosal, musculoskeletal, renal, antiphospholipid antibodies, complement proteins, and SLE-specific antibodies.^3,4

The malar (“butterfly”) rash of SLE characteristically includes erythema that spares the nasolabial folds but affects the nasal bridge and cheeks.⁶ The rash occasionally may be pruritic and painful, lasting days to weeks. Photosensitivity occurs, resulting in rashes or even an overall worsening of SLE symptoms. In those with darker skin tones, erythema may appear violaceous or may not be as readily appreciated.⁶

Worth noting

• Patients with skin of color are at an increased risk for postinflammatory hypopigmentation and hyperpigmentation (pigment alteration), hypertrophic scars, and keloids.^7,8
• The mortality rate for those with SLE is high despite early recognition and treatment when compared to the general population.^1,9

Health disparity highlight

Those at greatest risk for death from SLE in the United States are those of African descent, Hispanic individuals, men, and those with low socioeconomic status,⁹ which likely is primarily driven by social determinants of health instead of genetic patterns. Income level, educational attainment, insurance status, and environmental factors¹⁰ have farreaching effects, negatively impacting quality of life and even mortality.

THE COMPARISON

A A 23-year-old White woman with malar erythema from acute cutaneous lupus erythematosus. The erythema also can be seen on the nose and eyelids but spares the nasolabial folds.

B A Black woman with malar erythema and hyperpigmentation from acute cutaneous lupus erythematosus. The nasolabial folds are spared.

C A 19-year-old Latina woman with malar erythema from acute cutaneous lupus erythematosus. The erythema also can be seen on the nose, chin, and eyelids but spares the nasolabial folds. Cutaneous erosions are present on the right cheek as part of the lupus flare.

JFP07206e1_f1.jpg

Systemic lupus erythematosus (SLE) is a chronic autoimmune condition that affects the kidneys, lungs, brain, and heart, although it is not limited to these organs. Dermatologists and primary care physicians play a critical role in the early identification of SLE (particularly in those with skin of color), as the standardized mortality rate is 2.6-fold higher in patients with SLE compared to the general population.¹ The clinical manifestations of SLE vary.

Epidemiology

A meta-analysis of data from the Centers for Disease Control and Prevention National Lupus Registry network including 5417 patients revealed a prevalence of 72.8 cases per 100,000 person-years.² The prevalence was higher in females than males and highest among females identifying as Black. White and Asian/ Pacific Islander females had the lowest prevalence. The American Indian (indigenous)/Alaska Native–identifying population had the highest race-specific SLE estimates among both females and males compared to other racial/ethnic groups.²

Key clinical features in people with darker skin tones

The diagnosis of SLE is based on clinical and immunologic criteria from the European League Against Rheumatism/American College of Rheumatology.^3,4 An antinuclear antibody titer of 1:80 or higher at least once is required for the diagnosis of SLE, as long as there is not another more likely diagnosis. If it is present, 22 additive weighted classification criteria are considered; each criterion is assigned points, ranging from 2 to 10. Patients with at least 1 clinical criterion and 10 or more points are classified as having SLE. If more than 1 of the criteria are met in a domain, then the one with the highest numerical value is counted.^3,4

Aringer et al^3,4 outline the criteria and numerical points to make the diagnosis of SLE. The mucocutaneous component of the SLE diagnostic criteria^3,4 includes nonscarring alopecia, oral ulcers, subacute cutaneous or discoid lupus erythematosus,⁵ and acute cutaneous lupus erythematosus, with acute cutaneous lupus erythematosus being the highest-weighted criterion in that domain. The other clinical domains are constitutional, hematologic, neuropsychiatric, serosal, musculoskeletal, renal, antiphospholipid antibodies, complement proteins, and SLE-specific antibodies.^3,4

The malar (“butterfly”) rash of SLE characteristically includes erythema that spares the nasolabial folds but affects the nasal bridge and cheeks.⁶ The rash occasionally may be pruritic and painful, lasting days to weeks. Photosensitivity occurs, resulting in rashes or even an overall worsening of SLE symptoms. In those with darker skin tones, erythema may appear violaceous or may not be as readily appreciated.⁶

Worth noting

• Patients with skin of color are at an increased risk for postinflammatory hypopigmentation and hyperpigmentation (pigment alteration), hypertrophic scars, and keloids.^7,8
• The mortality rate for those with SLE is high despite early recognition and treatment when compared to the general population.^1,9

Health disparity highlight

Those at greatest risk for death from SLE in the United States are those of African descent, Hispanic individuals, men, and those with low socioeconomic status,⁹ which likely is primarily driven by social determinants of health instead of genetic patterns. Income level, educational attainment, insurance status, and environmental factors¹⁰ have farreaching effects, negatively impacting quality of life and even mortality.