Dermatitis herpetiformis: immunoelectronmicroscopic and ultrastructural studies of a patient with linear deposition of IgA.

Using immunoelectronmicroscopic techniques, we have demonstrated three distincet patterns of IgA deposition in the skin of patients with dermatitis herpetiforms. The least common of these patterns is the localization of reaction products to the lamina lucida. As this is the location of the immunoreactants in bullous pemphigoid and herpes gestationis and because the ultrastructural findings in our patient's early lesional skin differ from those usually seen in patients with dermatitis herpetiformis, we herein detail this patient's clinical, histologic, immunologic, and ultrastructural findings. The most prominent findings are (1) IgA deposition in the lamina lucida, (2) vesicle formation between basal lamina and the basal cells, and (3) fibrin-like material in the epidermis with showering into the dermis.