ABSTRACT
We report the third case of cutaneous lichen planus (LP) following COVID-19 BNT162b2 vaccination in a 59-year-old woman with previous LP. The reactivation of LP in patients with dormant LP suggests a possible vaccine-induced immune dysregulation. We suggest that the already described vaccine-induced upregulation of Th1 response may play a relevant role in LP reactivation, through an increase in inflammatory cytokines involved in the pathogenesis of LP. Interestingly, LP has already been associated with vaccinations and viral infections including COVID-19 disease. However, the exact mechanism underlying LP (re)activation after Pfizer-BiotNtech COVID-19 vaccination is still widely unknown and needs to be further investigated.
ABSTRACT
INTRODUCTION: Coronavirus disease 2019 (COVID-19) vaccines can cause adverse reactions, mainly from vaccine-induced immune responses. Some of these may also involve the skin and worry unaware patients. A better understanding of such adverse reactions may reduce concerns and help promote the vaccination of large population groups. METHODS: All the reports of patients admitted to our Dermatology Primary Care, from March 2021 to June 2021, were retrospectively examined to collect descriptive data on skin reactions arising after COVID-19 vaccination. RESULTS: Out of 200 vaccinated patients admitted to the Dermatology Primary Care, 21 (10.5%) referred cutaneous reactions with onset after vaccination. Only one patient required hospitalization for generalized bullous erythema multiforme, which occurred 48 h after the second vaccine dose. The other patients' cutaneous reactions to vaccination were of mild/moderate degree. Three patients presented exacerbation of their cutaneous diseases. CONCLUSIONS: Cutaneous reactions observed in our sample were mostly mild or moderate. Awareness must be raised to recognize and treat eventual severe reactions. Future studies are needed to assess the incidence of cutaneous reactions following COVID-19 vaccination.