Abstract

A 58-year-old female, known case of diabetes mellitus, followed up with rheumatology as a case of Behçet disease, developed sudden-onset generalized flaccid bullae and mucosal erosions shortly after switching from azathioprine to adalimumab. Histopathology and direct immunofluorescence were consistent with pemphigus vulgaris. She was successfully treated with systemic corticosteroids, azathioprine, and rituximab, showing excellent clinical improvement. The patient was seen in the clinic after 2 months with no relapse. This case highlights the importance of recognizing overlapping autoimmune phenomena in Behçet disease and differentiating true Behçet mucocutaneous activity from drug-induced or coincident autoimmune blistering disorders.

Key words: Keywords: Pemphigus vulgaris, Behçet disease, Autoimmune blistering disease, Adalimumab, TNF-α inhibitor, Rituximab