LINEAR IGG AND IGA BULLOUS DERMATOSIS WITH CONCOMITANT IMMUNOHISTOCHEMICAL AND IMMUNOLOGICAL CHARACTERISTICS - A NEW ENTITY OR AN OVERLAPPING OF BULLOUS PEMPHIGOID AND LINEAR IGA DERMATOSIS

We report an unique case of subepidermal bullous disease featuring lin ear IgG and IgA deposits in the basement membrane zone (BMZ) in a 58-y ear old woman. This patient had two types of skin manifestations: larg e, tense bullous pemphigoid-like bullae on the flexor aspects of the f orearms, and annular exudative erythema dermatitis herpetiformis on th e trunk. Histological and immunohistochemical examination revealed sub epidermal edema with infiltrating eosinopils and linear IgG, IgA and C 3 deposition in both the BMZ and the intercellular spaces. Circulating IgG and IgA anti-BMZ antibodies were identified. In immunoblot analys is, the patient's serum reacted with the 170 kD bullous pemphigoid ant igen and the 97 linear IgA dermatosis antigen. The diversity of the cl inical features, the immunohistologic findings and immunologic analysi s of the serum antibody indicated an overlapping or transitional state between classical bullous pemphigoid and linear IgA dermatosis.