Annular plaques mimicking Rowell's syndrome in the course of coronavirus disease 2019 mRNA vaccines: An overlooked phenomenon?

Effective vaccines for prevention of severe course and lethal outcome of coronavirus disease 2019 have been developed and approved in regulatory rolling and fast-track procedures; they are now widely distributed worldwide. Data about cutaneous side-effects of the new mRNA-type vaccines is scant, however. We herein report two similar cases of cutaneous adverse drug reactions (ADR) mimicking Rowell's syndrome that occurred after the first dose of BNT162b2 and mRNA-1273, respectively. Both patients achieved prompt clinical improvement with a short pulse of oral prednisolone and non-steroidal inflammatory drugs. We suspect this phenomenon to occur in a timeframe of 7-14 days after vaccination due to an interferon-γ-driven shift towards type I immunity in susceptible individuals. As rheumatic patients were excluded from phase III clinical trials and as most countries prioritized the elderly population to receive the vaccinations first, cutaneous ADR might become more frequent once the younger part of the population is vaccinated over the course of 2021. Atypical cutaneous ADR might be misinterpreted or overlooked by non-dermatologists. Further studies are required to determine the best suitable vaccine types for individual groups of patients.