Comparative analysis of the geographic distribution of the histopathological spectrum and Leishmania species of American cutaneous leishmaniasis in Brazil

BACKGROUND: Knowledge of the relationship between specific geographical differences and histopathology of the American cutaneous leishmaniasis is limited because host-parasite interactions in space and time are complex. OBJECTIVE: To describe the geographic analysis of the histopathological pattern of localized American cutaneous leishmaniasis and the relationship with Leishmania species. METHODS: A cross-sectional, descriptive and analytical study of a sample consisting of 55 patients of municipal districts of Montes Claros and 32 of Caratinga, Minas Gerais, by comparing with other endemic regions in Brazil, assessing historical and microregional data and developing confidence intervals. RESULTS: A preponderance of cellular exudative reactions in the cutaneous form of American cutaneous leishmaniasis was found in the municipal districts of Caratinga, east of Minas Gerais, Montes Claros, north of Minas Gerais and Uberlândia, Triangulo Mineiro, and also in the states of Mato Grosso and Ceara. Necrotic and exudative granulomatous reactions were found to be more frequent in the northern areas, mainly in the states of Amazonas and Para. Necrotic and exudative reactions were the most frequent form of presentation found throughout Brazil when the predominance of L. braziliensis was below 90% in relation to other species. CONCLUSION: There is a geographic variation of the immune inflammatory response in American cutaneous leishmaniasis. Geographical correlations between the predominant species of Leishmania and the most frequent forms of histopathological presentation of American cutaneous leishmaniasis, which until the present study had not been performed, enables new approaches to the study of Leishmania subpopulations in areas with a predominance of one species and provides evidence of variations in the biological behavior of different species.