# An Unusual Presentation of Erythema Multiforme Following the Administration of Pfizer-BioNTech COVID-19 mRNA Vaccine in a Pediatric Patient

## TL;DR

A 14-year-old girl developed erythema multiforme after receiving the Pfizer-BioNTech COVID-19 vaccine, a rare but reported side effect.

## Contribution

This case adds to the limited reports linking the BNT162b2 vaccine to erythema multiforme in pediatric patients.

## Key findings

- Erythema multiforme was observed in a previously healthy 14-year-old girl after the first dose of the BNT162b2 vaccine.
- This case is among 14 reported cases of new-onset erythema multiforme following the BNT162b2 vaccine.
- Erythema multiforme is a rare but documented cutaneous reaction to the Pfizer-BioNTech vaccine.

## Abstract

Coronavirus disease 2019 (COVID-19) caused a global calamity that forced emergency use authorization to Pfizer-BioNTech COVID-19 (BNT162b2) vaccine. It is efficacious in preventing symptomatic severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in seronegative recipients. The safety profile is still unclear; however, commonly reported symptoms post-vaccination are fatigue, headache, muscle pain, chills, and injection-site pain. COVID-19 disease elicits, to some extent, cutaneous side effects like urticaria, morbilliform rash, and chilblain-like eruption. Vaccination against COVID-19 was reported to induce similar dermatologic manifestations, such as urticarial rash, delayed large-local reaction, local injection-site reaction, and morbilliform eruption. Erythema multiforme (EM) is a rare manifestation post-vaccination, and only a few reports implicate it as a culprit in cutaneous eruptions following the BNT162b2 vaccine. This report delineates the presentation of a healthy 14-year-old girl to a dermatology clinic who developed EM post-vaccination with the first dose of BNT162b2. New-onset EM-eruption post-vaccination with BNT162b2 had been reported previously in 14 cases, and one case reported on the flare of preexisting-EM.