Chronic bullous disease with coexistent circulating IgG and IgA anti-basement membrane zone antibodies.

Coexistent circulating IgG and IgA anti-basement membrane zone (BMZ) antibodies were demonstrated in a patient with chronic bullous disease. Direct immunofluorescence microscopy showed IgG, IgA, and C3 deposits in a linear pattern at the BMZ in the patient's uninvolved skin. Ultrastructurally, the bulla was formed beneath the basal lamina as in dermatitis herpetiformis. This investigation might provide evidence for the immunologic overlap of bullous pemphigoid and dermatitis herpetiformis.