Differential diagnosis of eczema and psoriasis in very dark skin
Differential diagnosis of eczema and psoriasis in very dark skin
Tips and recommendations for diagnosis where erythema is concealed (1,025 words, 5 minutes)
Differential diagnosis between atopic dermatitis (eczema) and psoriasis can be more challenging in Fitzpatrick skin types V and VI because dark pigment can conceal erythema, noted Dr. Jaggi Rao at the virtual Colloquium on Black Skin on Saturday, Aug. 21. The Colloquium was presented as part of the Skin Spectrum Summit’s Summer of Dialogue on Black and Brown Skin.
During a live discussion at the Colloquium, Dr. Rao noted that erythema, thickness and scale morphology for each lesion are the first clues used for differential diagnosis of the two conditions.
While evaluations based on erythema are less effective in patients with very dark skin, the other two signs are still useful in this population. Other clues can also help distinguish the two conditions.
Some of the distinguishing features Dr. Rao noted include:
Lesion thickness—psoriasis lesions tend to be thicker
Scale adhesion—typical psoriasiform scale tends to be more adherent.
Anatomic distribution—lesions are more common in different body areas in AD and psoriasis. Ask patients about lesions in the groin area or the scalp, and check nails for psoriasis signs.
History of itch—eczema is more frequently itchy than psoriasis, and itching may occur before lesions appear.
History of prior treatments.
Bottom line:
Redness is not a useful diagnostic tool for psoriasis or eczema in very dark skin, so other signs should be considered. If the diagnosis remains unclear, a biopsy will usually be definitive.
From the literature on psoriasis and eczema
Transcriptomic analysis of atopic dermatitis in African Americans is characterized by Th2/Th17-centered cutaneous immune activation
The authors of this study note that atopic dermatitis (AD) is often more severe in individuals of African descent. To understand why, they studied immune signatures in a cohort from this population with moderate-to-severe pruritus, taking biopsies from lesional and non-lesional skin. These biopsies were also compared to biopsies taken from matched controls. Overall their findings suggest that AD patients of African descent may experience broader immune activation than previously thought and may benefit from systemic immunomodulating therapies that modulate key drivers of multiple immune pathways.
Successful management of a Black male with psoriasis and dyspigmentation treated with halobetasol propionate 0.01%/tazarotene 0.045% lotion: Case report
A 58-year-old Black male with moderate psoriasis was treated for eight weeks with a fixed combination halobetasol propionate 0.01%/tazarotene 0.045% (HP/TAZ) lotion during a phase 3 study. In this case report, the investigators report that the HP/TAZ combination was efficacious in treating this patient’s psoriasis. The patient’s Investigator’s Global Assessment score decreased from moderate to almost clear within four weeks and was maintained there through week 12—four weeks post-treatment. The patient did experience dyspigmentation, but his skin had mostly returned to normal by week 12. The authors conclude that the HP/TAZ combination could be a treatment option for patients with darker skin who are more prone to postinflammatory dyspigmentation.
Racial/ethnic variations in skin barrier: Implications for skin care recommendations in skin of colour
This review article found that several studies compare ethnic groups’ physical and biochemical skin barrier properties, and these have reported differences in transepidermal water loss (TEWL), skin lipid levels, pH, and mast cell granule size. However, the review authors note that these studies frequently had methodological flaws, mainly were small, and demonstrated conflicting results. As well, ethnic categories based on race and ethnicity are often not well defined and inconsistent across different studies.
The literature suggests racial or ethnic variations in ceramide content, the structure of the stratum corneum, and filaggrin mutations. They also identified a greater burden of pruritus and atopic dermatitis among Black populations. There is less data on barrier properties in Hispanic or LatinX and South Asian populations.
Association of KIR genes and MHC class I ligands with atopic dermatitis
This study of genes related to the function of natural killer (NK) cells in atopic dermatitis (AD) identified several killer cell Ig-like receptor (KIR)-related ligands associated with higher AD risk. Of note, the investigators found that African Americans with KIR2DL2, KIR2DS1, KIR2DL5, and KIR2DS5 variants were more likely to have AD—especially individuals who also have certain variations in antigen-binding sites.
The investigators conclude that future studies of AD pathology should focus on variations in KIR genes and consider cell-based measurements of KIR and associated antigen-binding sites.
VIDEO: Hispanic and black children more likely to miss school due to atopic dermatitis
At the intersection of skin and society
The Black Screen Office cooperates with TELUS STORYHIVE to offer Black filmmakers and content creators the chance to share their stories through the Black Creators Edition of STORYHIVE, reports Vancouver digital newspaper Daily Hive.
TELUS STORYHIVE is a community-powered funding program for content creators in British Columbia and Alberta. The Black Screen Office is a not-for-profit organization supporting Black Canadians working in the screen industries.
Cameron Zinger, director of TELUS STORYHIVE, told the news outlet that the new project was “created to help empower the next generation of creators.” The Black Creators Edition will award production grants of $20,000 to 20 Black filmmakers and content creators across BC and Alberta.
Successful applicants will also receive customized career training, filmmaking mentorship, and distribution of their projects on select TELUS platforms.
Formats eligible for consideration include fiction, non-fiction, digital short, web series pilot, drama, comedy, or documentary.
Award recipients will be selected by a committee of Black leaders from the screen industry and Black community members.
Applications will be accepted until Oct. 6, 2021.
More information and the opportunity to apply can be found at this link:
This Week
September is Childhood Cancer Awareness Month
September is National Headlice Prevention Month in the US
Sept. 20-26 is National Organ Donation Week in the UK
Something to think about in the week ahead...
Looking ahead:
Additional faculty have been confirmed for the 7th Annual Skin Spectrum Summit on Nov. 4 and 6, 2021. The Summit is Canada’s leading ethnodermatology medical conference for physicians.
Some of the leading experts on skin of colour who will be presenting at the Summit in November include:
Dr. Renita Ahluwalia
Dr. Afsaneh Alavi
Dr. Bolu Ogunyemi
Dr. Rachel Netahe Asiniwasis
Skin Spectrum Weekly will bring you more news on faculty and topics for this year’s Summit as we get closer to the date.
Register today for the conference or find more information on the 2021 and prior Summits at SkinSpectrum.ca