Metformin induced Bullous pemphigoid - A Rare Case Report

Abstract

Bullous Pemphigoid(BP) is a chronic, acquired autoimmune skin disease. Exact etiology of this autoimmune process is not known. Certain drugs such as furosemide, penicillins, sulfonamides, ciprofloxacin, penicillamines, Angiotensin Converting Enzyme(ACE) inhibitors, chloroquine,etanercept,  and phenacetin were reported to cause BP. Metformin is also a rarer one to cause BP. This is a case report of a 58-year-old female recently diagnosed with Type 2 Diabetes Mellitus(T2DM), started on Metformin, presented with the formation of few cutaneous tense bullae on both distal forearm. Clinical finding of skin lesions and direct immunofluorescence (DIF) finding were consistent with BP. To our best knowledge, this is among the very few cases of Metformin induced BP in the literature.