[Dermatitis herpetiformis Duhring with linear deposits of IgA (linear IgA dermatosis)]

Three patients with linear deposits of IgA along the epidermal basement membrane were studied. The clinical and histopathological picture as well as the response to dapsone were typical of dermatitis herpetiformis. Two of the three patients were HLA-B8/DR3-positive. By immunoelectron microscopy, the previously reported two types of linear IgA deposits were confirmed: in one patient, the IgA precipitates were localized below the basal lamina as in dermatitis herpetiformis, in the other two above the basal lamina in the lamina lucida as in bullous pemphigoid. The immunoelectron microscopic findings imply that in some patients with linear IgA dermatosis a pathomechanism different from that in classical dermatitis herpetiformis may be operative.