Antigen identification in drug-induced bullous pemphigoid

Immunobullous diseases usually develop spontaneously, but drug-induced bullous disease develops in a small subgroup of patients. We examined a patient in whom bullous pemphigoid developed after she received enalapril for treatment of hypertension. IgG antibody directed against a 230 kd antigen was identified. The eluted IgG autoantibody was shown to bind to the basement membrane zone on split skin. This study demonstrates that drug-induced bullous pemphigoid autoantibody in this patient was directed against the same antigen as the spontaneous bullous pemphigoid antigen.