A new variant of endemic pemphigus foliaceus in Colombia South America

A new variant of endemic pemphigus foliaceus in El Bagre and surrounding municipalities (El Bagre-EPF), also titled pemphigus Abreu-Manu, is a complex disease that has a genetic component and likely environmental triggering factors. The disease is present only in certain high-prevalence areas and affected individuals present in a unique cluster, that represent opportunities to study interactions of the environment and genetics with the immune system. The primary autoantibodies are directed to known cell junctions, but also directed to recently discovered ones that are formed via amalgamation of classic cell junctions. Besides desmoglein 1, main autoantigens are members of the p120 and plakin families, myocardial zonula adherens protein, and the armadillo repeat gene deleted in velo-cardio-facial syndrome. Other autoantibodies are directed to cell junctions in neurovascular bundles and neural receptors. A possible genetic founder effect in Indians may predispose individuals to this disease. El Bagre-EPF prevails in males after their forties and occasionally affects peri-postmenopausal females. Ultraviolet radiation is a main exacerbating factor of the disease, and seborrheic areas are most frequently affected. One third of the patients have a mild form of the disease with minimal clinical findings; one third of the patients show moderate clinical features with alterations in the skin and other organs, and one third of the patients show multiorgan systemic abnormalities, which are manifested clinically, histopathologically and immunologically. Mining, deforestation, environmental pollution and alterations in the ecosystem may partially trigger El Bagre-EPF.