Presentation of AD in Black children
Diagnostic signs key to diagnosing eczema in Black children are rare or unseen in White children (1,400 words, 7 minutes)
Black children have a six-times greater risk for severe atopic dermatitis (AD) than White children, and Indigenous children have a similarly elevated risk. However, the common scoring systems for AD that rely on erythema or redness dramatically underestimate severity in more richly pigmented skin tones. This can lead to delays in diagnosis and treatment that disproportionately affect patients with skin of colour.
This was a key message from Dr. Marissa Joseph, speaking at the inaugural Summit on Atopic Dermatitis virtual meeting on April 23, 2022.
“When we look at different skin diseases, particularly atopic dermatitis because it is so common, it is important to understand both what the diagnostic challenges are but also nuances and features that aid in diagnosis,” said Dr. Joseph. “Locally for us, this is very relevant because in Canada, we have the highest per-capita immigration rate in the world. Toronto has been described as the most diverse city in the world. So we have to take notice and—to serve our patients with atopic dermatitis—recognize some of the differences in clinical presentation.”
Using pediatric case images, Dr. Joseph showcased several presentations of AD that occur in patients with dark skin that are rare in lighter skin tones.
Lesions may be violaceous, greyish, red-brown or dark brown
Involved areas may be dyspigmented
Follicular accentuation can be more common
Lichenification may occur
Plaques may have a nummular or coin-like shape
Extensor surfaces such as the outside of the knee or elbow may be involved
Lesions may take the form of prurigo nodularis
It is important that physicians not assume hypopigmentation is post-inflammatory, Dr. Joseph said, as inflammatory processes may still be quite active while dyspigmentation is present.
The potential for lichenification or other profound skin changes caused by AD in patients with dark skin is important to keep in mind when discussing treatment with patients, Dr. Joseph noted. “People are very fussed and worried about thinning of the skin and potential skin changes from [prescription] topical treatment. But we must remember that there are significant skin changes that are possible from the disease itself.”
Bottom line:
Pediatric AD can present very differently in skin of colour compared to White skin, and knowing which signs indicate AD in this population can help patients receive the correct diagnosis and treatment sooner.
From the literature on AD in skin of colour
Association between atopic dermatitis and race from infancy to early childhood: A retrospective cohort study
This single-site, retrospective cohort study included infants born from June 1, 2011, to April 30, 2017, with the goal of better understanding the factors that contribute to racial differences in AD prevalence.
A total of 4,016 infants were included. Of those, 39.2% (n=1,574) were Black, 38.5% (n=1,543) were non-Hispanic White, 7.1% (n=286) were Hispanic, 5.3% (n=213) were Asian, 6.5% (n=262) self-reported as being “other,” 3.4% (n=135) were multiracial, and 0.1% (n=3) did not report any race.
The investigators found that AD prevalence differed by race, with 37.0% (n=583) of Black, 25.8% (n=55) of Asian, 24.1% (n=69) of Hispanic, 23.0% (n=31) of multiracial, 19.1% (n=50) of "other" race, and 17.9% (n=276) of White patients diagnosed (p<0.0001).
They also found that delivery mode, NICU stay, and gestational age were all significantly associated with race. They concluded that racial differences in rates of AD appear early in life and that diagnosis of AD is more associated with race than delivery mode, insurance type, or gestational age.
Longitudinal atopic dermatitis endotypes: An atopic march paradigm that includes Black children
This paper aimed to identify how the atopic march differs between Black and White children and find potential causes for those differences.
Using data from the Mechanisms of Progression of Atopic Dermatitis to Asthma in Children (MPAACH) cohort (n=601), the researchers compared several factors between Black and White children. These included sensitization over time, food allergy, allergic rhinitis, the risk of asthma development, Scoring for Atopic Dermatitis (SCORAD), transepidermal water loss, skin filaggrin (FLG) expression, exposures, and genetic heritability.
They found that White children in the cohort were more likely to be sensitized to airborne and food allergens and more than three times as likely to develop a food allergy or allergic rhinitis without asthma risk compared to Black children. On the other hand, Black children were more than six times as likely to proceed to high asthma risk without food allergy, sensitization, or allergic rhinitis.
White children had a higher transepidermal water loss in lesional and non-lesional skin. They also had decreased expression of skin filaggrin in nonlesional skin.
Genetic heritability of asthma risk was higher in Black children, and those children were also more often exposed to secondhand smoke and traffic-related air pollution.
Assessment and monitoring challenges among patients with moderate-to-severe atopic dermatitis across Fitzpatrick skin types: A photographic review and case series
This review article looks at variation in the clinical presentation of AD across the spectrum of Fitzpatrick skin types, emphasizing clinical evaluation challenges in patients with skin of colour.
The authors present a series of photographs from phase 3 clinical trials of upadacitinib as a treatment for moderate-to-severe AD. They discuss the challenges of evaluating AD's clinical signs, including erythema and excoriation in patients with dark skin types and lichenification in patients with light skin types. As well, the authors discuss the changes in clinical signs and symptoms that can be achieved with targeted systemic therapies.
Vitamin D, skin filaggrin, allergic sensitization, and race
To explore the role of circulating vitamin D levels in allergic sensitization, researchers studied levels of circulating vitamin D in the blood of 323 children—a subset of the Mechanisms of Progression of Atopic Dermatitis to Asthma in Children cohort.
Skin prick testing was used to determine allergic sensitization, and researchers measured filaggrin expression in children’s keratinocytes.
The researchers found that Black participants had significantly lower mean serum vitamin D levels than non-Black participants (29.3 vs 32.9 ng/mL; p<0.001). Filaggrin expression and sensitization load were negatively correlated in non-Black participants with vitamin D levels less than 27.2 ng/mL (Rho=-0.45; p=0.02).
There was no association between filaggrin expression and sensitization load in Black participants or participants with vitamin D levels greater than or equal to 27.2 ng/mL.
VIDEO: Eczema in skin of colour: What you need to know
At the intersection of skin and society
Descendants of the Plains Cree leader Pihtokahanapiwiyin, known as Chief Poundmaker, have repatriated a ceremonial staff of historic significance stolen from him following the Northwest Resistance in 1885, reports the CBC.
Poundmaker and other First Nations leaders were wrongly accused of instigating violence, and Poundmaker was convicted and jailed in 1885 for “treason-felony.” At the time, many of his belongings were seized. Those items then ended up in museums across Saskatchewan and around the world. Poundmaker’s staff was in the possession of Parks Canada.
Pauline Poundmaker, the great-great-granddaughter of the famous chief, requested repatriation of the staff and accepted it from Parks Canada in a ceremony at the Fort Battleford National Historic Site in Battleford, Sask., May 4, 2022.
“Today is … another historic day,” the news outlet reported Pauline saying. “I'm thinking about my mother … and how proud she would be.”
According to the CBC, the Poundmaker family and their community have been working for many years to repatriate various items taken from Poundmaker during the events of 1885.
Pauline said she learned in roughly 1996 about a sacred artifact that belonged to her great-great-grandfather and first learned about repatriation protocol. Poundmaker's ceremonial war club and other items were repatriated earlier, in 2017.
Floyd Favel, the curator of the Chief Poundmaker Museum, is quoted saying that the family has the right to all of Poundmaker's items.
“This event today is a good closing of a circle, one circle,” he said.
“Hopefully, the authorities and other institutions in Canada and in the United States and the world can recognize our loss and give these items back to correct history.”
This week
May is Food Allergy Awareness Month in Canada
May 9 is National Women’s Checkup Day in the U.S.
May 12 is International Nurses Day
Something to think about in the week ahead…
Next week
A shortage of images of dermatologic conditions in skin of colour in medical image libraries could reinforce disparities of care if artificially intelligent ‘smart’ diagnostic systems are trained on the skewed image atlases. This caution was discussed by Dr. Jenna Lester, a dermatologist at the University of California San Francisco, in a talk at the seventh annual Skin Spectrum Summit.