What's hot?
What's hot
October 1, 2019
In this monthly column, members of Dermatology World's Editorial Advisory Workgroup identify exciting news from across the specialty.
Should dermatologists be familiar with the effects of climate change? The answer is yes. In July’s issue of Dialogues in Dermatology, Dr. Misha Rosenbach highlights the importance of the skin-environment interface. Although climate change is often thought of as a political and environmental issue, dermatologists should be familiar with how climate change is “changing the game” for dermatologists, particularly in the realm of the infectious diseases we see and treat.
For example, why are we seeing more adults with hand-foot-mouth disease? There is a big link between humidity, temperature, and infectious disease patterns, and milder winters could explain why we are seeing more adults with the disease. In fact, there has been Chinese literature on HFM supporting this link, Dr. Rosenbach explains. With rising sea levels, warmer ocean temperatures, more flooding, and brackish water, we are looking at infections like vibrio vulnificus, zygomatic and atypical mycobacterial infections.
How is climate change affecting disease vectors? “The Ixodes tick can live farther and farther north...so now there’s Lyme in places that it never existed,” said Dr. Rosenbach. This same concept also applies to what we have always considered tropical dermatology.’ For example, the Zika virus has moved up to the continental U.S. and the sand fly vector for Leishmania parasites is now is in Texas. So, “a lot of infections that are vector-borne, as the climate changes and the vectors move, we’re going to be seeing those infections in other places, where, if we’re not prepared for that or thinking about it, we’ll miss the diagnoses and harm will come to our patients.”
Lentigo maligna melanoma is a subtype of melanoma that occurs in chronically sun-damaged skin, frequently on the face of elderly patients. Since these may be large lesions in cosmetically sensitive areas, partial biopsies are often performed. Definitive treatment plans may be prepared without knowledge of final prognostic information (melanoma in situ vs. invasive melanoma with depth of invasion). In a recent retrospective study, the authors evaluated histopathology on partial biopsies of lentigo maligna and lentigo maligna melanoma for features that predict an invasive component (JAMA Derm. 2019;155(7): 782-788). Based on their study of 96 patients, the presence of melanocytes forming nests, rows, or subepidermal clefts in the epidermis was associated with invasion. Additionally, a decreased degree of solar elastosis was associated with having an invasive component. This study has limitations: retrospective methods, relatively small sample size, and no assessment of the degree of invasion. Some cases of lentigo maligna melanoma may be “microinvasive,” or thin level II, and carry a prognosis similar to melanoma in situ. Despite these limitations, this information may provide insight into a population of lower-risk MIS patients for which non-surgical management may be an option, and further studies are warranted. It is important to remember that surgery remains the treatment of choice for all forms of melanoma in situ.
Bullous pemphigoid (BP) commonly presents with tense bullae. However, BP can also present as pruritic non-bullous urticarial plaques. The enzyme-linked immunosorbent assay (ELISA) that detects BP180 and BP230 autoantibodies, direct immunofluorescence (DIF) and the indirect immunofluorescence (IIF) assays, and histopathology help to provide additional information in diagnosing BP. DIF has the highest sensitivity (90.8% - 95.7%) and negative predictive value (95.4% - 97.3%) and has been proposed to be a required criterion for diagnosing BP. The BP180 and BP230 ELISAs have very high specificities and positive predictive values (PPVs).The specificity of the BP180 ELISA is 94% and its PPV 95% - 96%. The specificity of the BP230 ELISA is 94% - 99% and its PPV 94% - 99%.
Patients with a negative DIF are unlikely to have BP. Patients with a positive ELISA are likely to have BP. However, a patient might have a negative DIF, but a positive BP180 or BP230 ELISA. This discrepancy may lead to uncertainty in the diagnosis.
A retrospective study over a 10-year period of patients who were ELISA+, DIF was performed (J Am Acad Dermatol. 2019; 81:472-9). The most common clinical presentation of ELISA+, DIF patients was eczema.
ELISA+, DIF patients had lower mean ages and lower BP180 or BP230 ELISA levels than ELISA+, DIF+ patients. Low-positive BP180 and BP230 autoantibody levels should not be interpreted as evidence for BP in the setting of a negative DIF. Most ELISA+, DIF patients did not have positive results on repeat DIF testing. A very small number might become DIF+ on repeat retesting. If there is high clinical suspicion for BP, high BP180 or BP230 autoantibody levels, older age, and histopathologic features, such as eosinophilic spongiosis, a repeat DIF should be performed.
FDA has unboxed — or, more literally, boxed — a new warning on tofacitinib.
A Janus kinase inhibitor, tofacitinib, was first approved by the Food and Drug Administration (FDA) in 2012 for treatment of rheumatoid arthritis (RA). Since then, it’s been approved for psoriatic arthritis and ulcerative colitis. It’s also been studied — and prescribed off-label — for autoimmune skin diseases, including vitiligo and alopecia areata.
When first approved in 2012, tofacitinib carried a Boxed Warning (“black-box warning,” in common parlance) about serious infections and malignancy. On July 26, 2019, FDA added new warnings to that Boxed Warning about an increased risk of blood clots and death with the dose of tofacitinib approved for treatment of ulcerative colitis (10 mg twice daily).
The new warning stemmed from analysis of data from an ongoing safety trial that FDA required when it initially approved tofacitinib for RA. In the trial, RA patients taking 10 mg of tofacitinib twice daily had an increased risk of blood clots in the lungs and death. Of note, the FDA-approved dose of tofacitinib for patients with RA— and for patients with psoriatic arthritis — is 5 mg twice daily. In the medical literature, doses of tofacitinib used in vitiligo or alopecia areata have reached 20 mg or higher daily.
In a Drug Safety Communication accompanying its announcement of the expanded Boxed Warning, FDA cautioned physicians regarding use of tofacitinib. Dermatologists considering treating patients with tofacitinib — on label or off — should consider not prescribing too far out of the box.
