Epidermolysis bullosa acquisita: what's new?

Abstract

Type VII collagen is an adhesion molecule of the extracellular matrix in epithelial basement membranes, and the main constituent of anchoring fibrils at the dermal-epidermal junction (DEJ). Autoimmunity against this protein is causing the rare organ-specific epidermolysis bullosa acquisita (EBA). EBA is a rare acquired, heterogeneous, chronic blistering disease of skin disease of skin and mucous membranes characterized by subepidermal blisters and tissue-bound as well as circulating autoantibodies to the DEJ. EBA has several distinct clinical presentations with other subepidermal bullous diseases, such as mainly dystrophic epidermolysis bullosa or bullous pemphigoid. The circulating immunoglobulin G autoantibodies for EBA react with a 290-kDa dermal protein, type VII collagen, as detected by immunoblot analysis using dermal extracts. The pathogenicity of these autoantibodies has been demonstrated by experimental animal models, in which anti-type VII collagen antibodies injected into a mouse produced an EBA-like blistering disease in the animal. EBA cases often require high doses of systemic corticosteroids and a variety of immunosuppressants. Although treatment for EBA is frequently difficult and unsatisfactory, some therapeutic success has been reported with colchicine, dapsone, infliximab and i.v. immunoglobulin. In this review, we will focus on recent progress in our understanding of the clinical manifestations, the etiopathogenesis as well as the management of EBA.