CONTINUING MEDICAL EDUCATION The new pemphigus variants

From the Division of Immunodermatology, Department of Dermatology, Northwestern University Medical School, Chicagoa; the Department of Dermatology, Kurume University School of Medicineb; the Department of Dermatology, Keio University School of Medicine, Tokyoc; and the Medicine Service, Section of Dermatology, Lakeside Division, Veterans Affairs Chicago Health Care System.d Supported by a Clinical Investigator Award (K08-AR01961, National Institutes of Health, Bethesda, Md) (to L. S. C.). Reprint requests: Lawrence S. Chan, MD, Department of Dermatology, Tarry 4-721, Mail Code T225, 300 E Superior St, Chicago, IL 60611-3010. E-mail address: [email protected]. Copyright © 1999 by the American Academy of Dermatology, Inc. 0190-9622/99/$8.00 + 0 16/2/96936 Pemphigus describes a group of chronic bullous diseases, originally named by Wichmann in 1791.1 All acquired forms of pemphigus are now characterized as autoimmune blistering diseases presenting clinically with flaccid intraepidermal blisters and erosions of the skin and mucous membranes, histologically with acantholysis, and immunopathologically with in vivo–bound and circulating autoantibodies against keratinocyte cell surface components.2 Pemphigus is usually divided into two distinct categories depending on blister location: pemphigus vulgaris and pemphigus foliaceus, each with its own variants (pemphigus vegetans and pemphigus erythematosus, respectively). Evidence has revealed that the IgG autoantibodies of patients with pemphigus vulgaris and pemphigus foliaceus recognize desmosomal components, desmoglein 3 and desmoglein 1, respectively.3-5 A complete review of these diseases, including pemphigus vulgaris, foliaceus, vegetans, and erythematosus, has been previously published.2 During the past 3 decades, rare forms of pemphigus have been described, including pemphigus herpetiformis, IgA pemphigus, and paraneoplastic pemphigus. Most of the autoantigens targeted by the autoantibodies from patients affected by these new pemphigus variants have been recently identified. In light of this new information, this article extensively reviews the clinical presentation, histology, immunopatholoCONTINUING MEDICAL EDUCATION