ABSTRACT
DEFINITION, ETIOLOGY, AND EPIDEMIOLOGY Pemphigus vulgaris (PV) is a chronic autoimmune blistering disease of the skin and mucous membranes which may be fatal unless treated aggressively. PV is caused by circulating immunoglobulin (Ig)G autoantibodies directed against the keratinocyte desmosomal proteins, desmoglein 1 (Dsg1) and desmoglein 3 (Dsg3). Dsg1 and 3 play an important role in cell-cell adhesion. Binding of the autoantibodies to Dsg1 and 3 induces the loss of normal cell adhesion in the epidermis, and subsequent blister formation. In the mucosal variant, autoantibodies exclusively react with Dsg3, whereas patients with the mucocutaneous variant have antibodies against both Dsg1 and 3.
