Challenges remain in diagnosing, treating skin of color with atopic dermatitis
Key takeaways:
- Atopic dermatitis is more common in Black patients, especially children.
- Erythema may be harder to identify in darker skin tones.
- Physicians may not be aware of these differences, impacting care.
PARK CITY, Utah — Physicians should mind variations in atopic dermatitis presentation among patients of different races, according to a presentation here.
“Atopic dermatitis presents differently in skin of color,” Melinda M. Rathkopf, MD, MBA, allergist and immunologist, Children’s Healthcare of Atlanta, said during her presentation at the Association of PAs in Allergy, Asthma and Immunology Annual Allergy, Asthma & Immunology CME Conference.
AD in children
AD affects up to 20% of children and up to 3% of adults overall, with prevalence increasing, particularly in low-income countries, Rathkopf said.
“It’s more common in Black Americans, especially children, and Black and Hispanic children tend to develop more severe cases compared to white children,” she continued, adding that it also is more common among Asian and Pacific Islander children.
AD often is the first step in the atopic march, Rathkopf said, with 50% of children with AD developing other allergic symptoms before age 1 year and 85% developing other allergic symptoms by age 5 years.
Additionally, Black and Hispanic children are more likely to miss school because of their AD. But despite these greater impacts, Rathkopf said, there is a disproportionate under-representation of minority populations in genetic and pharmacogenetic studies of both asthma and AD.
“There is a general lack of diversity in our medication education and research regarding atopic dermatitis in skin of color,” she said.
Severe cases of AD may not be diagnosed or treated adequately in children with deep pigmentation.
“Erythema, which is a defining characteristic in atopic derm, may be hard to identify in darker skin tones,” Rathkopf said. “Erythema on darker skin may be more gray, brown or purple.”
However, erythema may appear red or pink in lighter skin tones.
AD also may appear more papular with follicular accentuation and more lichenification in skin of color. There also may be more prurigo nodules and more pronounced post-inflammatory hypopigmentation and hyperpigmentation.
Social determinants of health
Barriers in getting care may compound these differences in diagnoses, Rathkopf said.
“The social determinants of health can result in limited or lack of transportation, patients missing or rescheduling doctor’s appointments, or forgoing or delaying their medication,” she said.
Income also can impact access to health care and health insurance. Some families with low incomes may live in areas where specialists are not available. They may skip medication as well, not because they are negligent but because costs are an issue.
“Can you afford the medication? Is it covered?” she said, adding that copays and even the cost of gas to drive to the pharmacy may be problems.
People who live in areas with substandard housing may experience more AD triggers such as dust mites, tobacco smoke and cockroaches. Heat can be a common trigger too, leading to more AD among residents of homes that lack air conditioning.
Education inequalities are another obstacle.
“A lack of knowledge and understanding of the skin condition can lead to problems such as using medications incorrectly or not following through with treatment,” Rathkopf said.
Also, patients with language or cultural differences may struggle with getting appropriate health care and with understanding their treatment plans.
“We all use translators when we need to. But there’s still a little bit lost in translation. You’re never exactly sure what’s being translated or understood,” Rathkopf said. “It doesn’t matter what you say to a patient or family. All that matters is what they hear.”
Additionally, challenging access to allergy-safe foods due to availability, cost or distance compound problems for patients whose food allergies impact their AD.
The communities where these patients live also may affect the health care that they receive, Rathkopf said.
“There may be few health care providers who have experience diagnosing and treating eczema in skin of color,” she said, adding that reading skin tests in very dark skin was personally challenging.
For example, she continued, many providers may rely on erythema for diagnosing AD. But when erythema is difficult to identify, providers need to look for other indicators.
Also, patients who cannot find a provider who speaks the same language that they do will have a difficult time communicating about their condition. Unable to fully understand the patient, Rathkopf said, these providers then may simply prescribe the same treatment they prescribe most other patients.
“Maybe that’s not the best treatment,” Rathkopf said.
Biological factors
Biological factors impact AD as well, Rathkopf said.
The ceramide component of the stratum corneum, which Rathkopf called essential in maintaining barrier integrity, differs based on ethnicity and race. Patients who are Black have lower ceramide/cholesterol ratios than patients who are white or Asian.
“So not only do we have all these social factors, but we have biological factors that are going to play a part in how it presents,” Rathkopf said.
Also, common loss of function mutations in the filaggrin gene have been associated with AD in European populations. These associations may be less relevant in patients who are Black, Rathkopf said, but studies vary.
Japanese and Korean patients with AD had higher numbers of T helper cells that cause inflammation, such as Th17 and Th22, compared with American patients of European descent, who may have more IL-4 and IL-13, Rathkopf continued.
“We’re looking at different inflammatory responses,” Rathkopf said. “We need a good algorithm that looks at that. What skin type you have might determine how we treat you.”
Finally, when the skin of African American and European American patients with AD were compared, Rathkopf continued, African American patients had lower numbers of certain Th1 and Th17 inflammation-causing cells and higher numbers of Th2 and Th22 inflammation-causing cells.
Treatment guidelines
Despite difficulties in diagnosing AD in patients with different skin color, Rathkopf said, physicians should strive for an accurate diagnosis. Treatment also generally is the same regardless of skin color, she continued.
Patients with darker skin may require higher doses of phototherapy with longer duration, Rathkopf advised, since the darker skin pigment acts as an ultraviolet filter. Also, she reminded the audience that patients with skin of color experience more hypopigmentation and hyperpigmentation.
“These [Eczema Area and Severity Index (EASI)] scores and [Investigator Global Assessment (IGA)] scores that look at your erythema and other things may be more challenging,” she said.
Topical steroids with high potency are more likely to cause hypopigmentation in patients with skin of color, Rathkopf continued. Monitoring patient response to treatment may be different as well, she said, since erythema appears differently.
“Much of what is currently known about atopic derm has been learned by studying white skin. Health care providers and researchers are acknowledging and addressing these gaps to improve knowledge and care of eczema in skin of color,” Rathkopf said.
Resources pertaining to these differences are available from organizations including the Allergy & Asthma Network, Eczema in Skin of Color, the Skin of Color Society, the National Eczema Association, the American College of Allergy, Asthma and Immunology and the American Academy of Allergy, Asthma and Immunology.
“Increasing the representation of skin of color in medical education, medical literature and health care workforce, including specialized clinical centers, will improve health care for people with skin of color,” she said.