Leukocytoclastic vasculitis (cutaneous small-vessel vasculitis) after COVID-19 vaccination

Vaccinations may induce cutaneous adverse events, due to nonspecific inflammation or immuno-mediated reactions. Several types of vasculitis have been observed. We report on a 71-year-old woman who developed cutaneous small-vessel vasculitis after the second dose of Vaxzevria COVID-19 vaccination, showing leukocytoclastic vasculitis on histopathological examination of a skin biopsy. Cutaneous small-vessel vasculitis is a rare condition which can be idiopathic or secondary to underlying infections, connective tissue disorders, malignancy, and medications. The pathogenesis involves immune complex deposition in small blood vessels, leading to activation of the complement system and recruitment of leukocytes. Exacerbation of small-vessel vasculitis has been reported following the administration of various vaccines, particularly influenza vaccine. It is expected that SARS-CoV-2 vaccine results in the activation of B- and T-cells and antibody formation. We hypothesize that leukocytoclastic vasculitis caused by immune complex deposition within cutaneous small vessels could be a rare side effect of Vaxzevria COVID-19 vaccination.