Rare infection induced recurrent erythema multiforme.

Erythema multiforme (EM) is an immune-mediated disease involving the skin and/or mucosa, whose aetiology is unclear and the most common predisposing factor is herpes simplex virus (HSV) infection. The presence of typical target-shaped erythema on the skin is key to its diagnosis. However, the diagnosis is a challenge for some patients whose lesions are limited to the oral mucosa. In this study, we reported a rare case of recurrent EM induced by Toxoplasma gondii infection. After confirming the diagnosis through serological testing, the patient was treated with anti-toxoplasma therapy alongside symptomatic management. This led to complete resolution of lesions with no recurrence over a 2-year follow-up period.