ABSTRACT
Background: The development of mucocutaneous reactions following COVID-19 vaccination has been increasingly documented. However, to date, there is still a dearth of studies that delve into the pathogenesis of these reactions.
Objectives: This study was aimed at correlating the spectrum of cutaneous reactions with histopathological findings developing after the administration of COVID-19 vaccination.
Materials and methods: In this prospective observational study, all the individuals developing any self-reported mucocutaneous adverse events within 3 weeks of receiving the COVID-19 vaccine were included. The lesions were classified into various reaction patterns on the basis of histopathological features.
Results: Out of the 103 vaccine-related reactions, only 53 patients agreed to get a skin biopsy done. The most common histological pattern of reaction was spongiotic dermatitis (n=23), clinically manifesting as pityriasis rosea like reaction, a maculopapular rash with fine scaling, and vaccine-related eruptions of papules and plaques (V-REPP). Other histopathological patterns included lichenoid dermatitis (n=18), leukocytoclastic vasculitis (n=4), dermal hypersensitivity reaction (n=2), subepidermal blistering (n=4), and granulomatous reaction (n=2). Other clinical patterns included, lichenoid skin eruptions, urticaria, vasculitis, pseudoangiomatosis, bullous pemphigoid, guttate psoriasis, herpes zoster, chilblains, and pityriasis lichenoides et varioliformis acuta. A majority of cases developed the reaction only after the 2nd dose of vaccination, suggesting the role of type IV hypersensitivity reaction.
Conclusion: Clinico-histopathological correlation helps in categorizing the various vaccine-related mucocutaneous reactions. Our work highlights that skin manifestations of the COVID-19 vaccine are often self-limiting and benign.