Encuesta epidemiologica de histoplasmosis, paracoccidioidomicosis y leishmaniasis mediante pruebas cutaneas

Abstract

In a village in Brazil's Amazonian jungle, skin test with histoplasmin, paracoccidioidin, and leishmanin were given to a group of 400 subjects aged 10 and older, of both sexes, who also responded to a questionnaire on their history of infectious diseases, There was a high prevalence of positive results in the three tests. The pattern of the results supports the hypothesis that testing with two mycotic antigens does not produce cross-reactions in asymptomatic subjects and that the sources of exposure to the fungi are probably independent. The positive reaction to leishmanin in males was related to farming activities, hunting, fishing, and the collection of firewood; the reactions in females showed a limited correlation with fishing and a much stronger one with the collection of firewood. With the mycotic antigens, the positive reactions were no associated with any of these activities. There was a high correlation of results using a leishmanin obtained from Leishmania Mexicana amazonesis and a combined leishmanin obtained from Leishmania mexicana and Leishmania brasiliensis. The diameter of induration was generally larger for the latter of these antigens, which induced some very intense responses. The frequency distribution of the magnitude of reaction was heterogeneous in subjects with positive reactions to both leishmanin and paracoccidioidin. Evidence that these findings are consistent with