Erythema Nodosum Manifestation Post COVID-19 Vaccine: A Case Report

Abstract
Erythema nodosum (EN) is a delayed hypersensitivity response that may be triggered by a range of conditions, including infections and vaccines. Rare cases of EN caused by COVID-19 were recently reported but none due to COVID-19 vaccines were documented. We report here a case of EN occurring after COVID-19 vaccination. Patient presented with painful nodular lesions of all 4 limbs, evolving for one month. These lesions appeared 48 h after the second dose of COVID-19 vaccination. The patient reported no recent infectious episodes. The physical examination found numerous, erythematous dermohypodermatitis knots with no palpable adenopathy. Some were regressive according to biligenesis shades. Biology and radiology findings eliminated other common causes of this dermatosis. The skin biopsy was done and suggested EN. The final diagnosis was post COVID-19 vaccine EN. Patient received a symptomatic treatment and had a slight improvement of the lesions 10 days after diagnosis. Physicians should be aware of the side effects of the vaccine including skin manifestations, especially since more people are bound to be vaccinated.