ABSTRACT
Fogo selvagem (FS) is an autoimmune bullous disease with pathogenic IgG autoantibodies recognizing desmoglein 1 (Dsg1), a desmosomal glycoprotein. In certain settlements of Brazil, a high prevalence of FS (3%) is reported, suggesting environmental factors as triggers of the autoimmune response. Healthy individuals from endemic areas recognize nonpathogenic epitopes of Dsg1, and exposure to hematophagous insects is a risk factor for FS. Fogo selvagem and Chagas disease share some geographic sites, and anti-Dsg1 has been detected in Chagas patients. Indeterminate Chagas disease was identified in a Brazilian Amerindian population of high risk for FS. In counterpart, none of the FS patients living in the same geographic region showed reactivity against Trypanosoma cruzi. The profile of anti-Dsg1 antibodies showed positive results in 15 of 40 FS sera and in 33 of 150 sera from healthy individuals from endemic FS sites, and no cross-reactivity between Chagas disease and FS was observed.
Subject(s)
Antibodies, Protozoan/blood , Autoantibodies/blood , Chagas Disease/epidemiology , Desmoglein 1/immunology , Endemic Diseases , Pemphigus/epidemiology , Trypanosoma cruzi/immunology , Adolescent , Adult , Aged , Autoantibodies/immunology , Brazil/epidemiology , Chagas Disease/diagnosis , Chagas Disease/ethnology , Chagas Disease/immunology , Child , Enzyme-Linked Immunosorbent Assay , Female , Humans , Indians, South American , Male , Middle Aged , Pemphigus/ethnology , Pemphigus/immunology , Risk Factors , Young AdultABSTRACT
Immunofluorescence is a valuable auxiliary diagnostic tool for autoimmune bullous diseases and inflammatory disorders, since their clinical and histopathologic findings may be inconclusive. It is a feasible laboratory method that requires experienced technicians and detects in situ and circulating immune deposits that may be involved in the pathogenesis of such skin diseases.
