Endemic pemphigus over a century: Part II

BACKGROUND Endemic pemphigus foliaceus (EPF) is an autoimmune disease, classically occurring in a restricted geographic area. Foci of EPF have been described in several Central and South American countries, often affecting young people and Amerindians, with some female predilection. Although most American EPF cases have been documented in Brazil, cases have been reported in Peru, Paraguay, El Salvador and Venezuela. An additional variant of EPF has been described in El Bagre, Colombia, (El Bagre-EPF) affecting older men and a few post-menopausal females. Finally, one additional type of EPF has been described in nomadic tribes affecting females of child bearing age in Tunisia, Africa. AIMS The main aim of this review is to summarize current knowledge about autoantigens, and immunologic and genetic studies in EPF. MATERIAL AND METHODS We utilized a retrospective review of the literature, aiming to compile and compare the multiple geographic foci of EPF. RESULTS The primary autoantigens in EPF are still considered to be desmogleins in the case of the Tunisian and all American cases, in contradistinction to plakins and desmogleins in El Bagre-EPF. Although several autoantigens are been suggested, their biochemical nature needs further elucidation. Current knowledge still supports the concept that an antibody mediated immune response represents the principal pathophysiology in all variants of EPF. CONCLUSION A strong genetic susceptibility appears to contribute to disease development in several people affected by these diseases; however, no specific genes have been confirmed at present. We conclude that further investigation is necessary to define these disorders immunologically and genetically.