Vasculitis After a Vaccine: Rare Adverse Reaction Following a COVID-19 Vaccine

Fatigue, fever, localized soreness, urticaria, and rash are common adverse reactions of COVID-19 vaccines. However, the occurrence of serious autoimmune reactions is quite rare. Cutaneous small-vessel vasculitis is an autoimmune disorder that manifests with palpable purpura and petechiae involving extremities. It results from neutrophilic inflammation within and around dermal vessels and is usually self-limited. We report a 55-year-old woman presenting with a rash 48 hours after receiving the third (Moderna) COVID-19 vaccine dose. Blood investigations and a skin punch biopsy confirmed the diagnosis of COVID-19 vaccine–induced cutaneous small-vessel vasculitis. The patient ultimately improved after inpatient treatment with systemic steroids.