This month’s news from across the specialty
What’s hot
April 1, 2022
In this monthly column, members of the DermWorld Editorial Advisory Workgroup identify exciting news from across the specialty.
There are so many great podcasts available through the AAD’s Dialogues in Dermatology. These podcasts offer short, high-yield interview sessions, from the leading experts in our field on a wide range of topics.
In December 2021, there is a bonus special available named ‘Best of AAD 2021 Summer Meeting’ which summarizes some of the hot sessions from the meeting, including a forum by George Han, MD, PhD, FAAD, on “So many biologics, so little time.” In the podcast, Dr. Han outlines some of the pearls that came out of the forum, which included what to do with psoriasis patients who keep failing multiple biologics. Some of this we think is due to antibody production against the drug, and that starting methotrexate with the start of the new biologic can be helpful. Because methotrexate has a dose-related response, sometimes you need to push the methotrexate dose up to get the response you want. There was also general agreement that you do not necessarily have to switch classes when a patient fails a biologic. Sometimes, patients will respond very well to biologics within the same class, particularly if they have a slightly different mechanism. There was also discussion on IL-17 inhibitors and IBD. There was general agreement that IL-17s do not actually cause IBD, but could be part of an “unmasking phenomenon” of pre-existing disease.
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The diagnosis of subungual melanomas can be difficult for dermatologists because biopsy of the nail unit is more challenging than other locations on the body. A recent paper in the Journal of Cutaneous Pathology presents insight into nail plate manifestations of subungual melanoma. Previous studies have shown that melanocytes in the nail matrix epithelium can be incorporated into the nail plate, and thus visible on histopathological examination of the nail plate. The recent paper has shown that large cellular remnants of melanocytes in nail plates are significantly higher in subungual melanomas than in nail matrix nevi. Additionally, in cases of melanoma, these large cellular remnants of melanocytes are more likely to be found in the dorsal part of the nail plate. The accompanying commentary by Rubin and colleagues reminds us that the gold standard for the diagnosis of pigmented lesions in the nail unit is a biopsy from the nail matrix. If these large cellular remnants of melanocytes are noted by the dermatopathologist, deeper sampling should be recommended. However, the absence of these melanocyte remnants does not definitively exclude a nail unit melanoma, and it is important to correlate with the clinical features including age, exact location, and clinical presentation.
Psoriasis affecting the hands and feet can be difficult to distinguish clinically from eczema. Unfortunately, a biopsy of an area thought to be volar psoriasis is of little diagnostic value, as it is challenging to differentiate it histologically from eczema. On volar surfaces, a biopsy specimen of psoriasis may lack the characteristic histologic features of psoriasis, while spongiosis can be prominent enough to resemble eczema (J Am Acad Dermatol. 2017; 77:130-5).
Often, patients complain of redness and/or scaling only on the palms or soles, and deny other areas of involvement. A thorough physical examination, including the elbows, knees, axillae, and intertriginous areas, may reveal classic features of psoriasis and lead the clinician to the correct diagnosis. Psoriasis of the hands and feet may be misdiagnosed as eczema if the clinician relies solely on histopathology. Biopsy of palmoplantar plaque psoriasis is not recommended. Instead, physical examination is more reliable for diagnostic clues.
More What’s Hot!
Check out more What’s Hot columns from the DermWorld Editorial Advisory Workgroup at the DermWorld homepage.
Herpes zoster (HZ) and its complications are more common among immunocompromised persons. Until recently, however, the zoster vaccine had not been licensed or recommended for them. In 2017, the vaccine — formally called Zoster Vaccine Recombinant, Adjuvanted, marketed as Shingrix, and given in two doses — was licensed by the FDA for prevention of HZ for adults aged ≥50 years, and recommended by the CDC’s Advisory Committee on Immunization Practices (ACIP) for immunocompetent adults aged ≥50 years.
In July 2021, FDA expanded the vaccine’s license to include adults aged ≥18 years with immunodeficiency or immunosuppression caused by known disease or therapy. Evidence came from efficacy and safety studies of adults with autologous hematopoietic stem cell transplants, hematologic malignancies, renal transplants, solid tumors receiving chemotherapy, or HIV infection.
FDA’s license determines who the vaccine can be marketed for. It’s ACIP, however, that makes critical public-health recommendations regarding who ought to receive the vaccine. In January 2022, after completing its own review of zoster vaccine efficacy and safety, ACIP recommended the vaccine for immunodeficient or immunosuppressed adults aged ≥19 years (yes, one year different from FDA’s license, to align with age ranges in the adult immunization schedule), including persons who have previously had HZ.
The FDA and ACIP reviews did not enroll persons with autoimmune and inflammatory conditions commonly treated by dermatologists, including those with immunosuppressive medicines. However, additional CDC guidance regarding vaccine use does include those groups. Dermatologists should be aware of this new ACIP recommendation and appropriately encourage vaccination for HZ prevention.
