Unusual clinical manifestation of linear IgA dermatosis: a report of two cases.

Linear IgA dermatosis is a rare autoimmune bullous skin disease with subepidermal blister formation and linear IgA deposits along the basement membrane zone. We describe two female patients showing erythematous annular plaques with scaling at the margin, strictly localized to the palms in one patient, and also found on the soles and buttocks in the second patient. Histology showed numerous neutrophils in the dermis with an admixture of eosinophils, some subepidermal clefting, and occasional papillary microabscesses. Direct immunofluorescence and immunoelectron microscopy revealed in vivo IgA deposition along the basement membrane zone. One patient cleared after treatment with dapsone. The second patient did not respond to dapsone alone and various immunosuppressive treatment regimens. Considerable improvement was achieved with intravenous immunoglobulin therapy combined with corticosteroid and dapsone.