Effect of chaotropes in Chagas disease and leishmaniasis cross-reacting serology assays for epidemiological surveys

• Published in: Revista da Sociedade Brasileira de Medicina Tropical
• Main Authors: Anderson Pacheco dos Santos, Maria Esther de Carvalho, Luciana Regina Meirelles, Heitor Franco de Andrade Junior
• Format: Article in Journal/Newspaper
• Language: English
• Published: Sociedade Brasileira de Medicina Tropical (SBMT)
• Subjects: Serology; Chagas disease; Leishmaniasis; ELISA; IFAT; IgG antibody avidity; Arctic medicine. Tropical medicine; RC955-962; Arctic
• Online Access: https://doi.org/10.1590/0037-8682-0391-2017; https://doaj.org/article/a6d633656b88483a9a49786b4dfa4aa4

Abstract INTRODUCTION: Serological cross-reactivity between leishmaniasis and Chagas disease, especially at low titers, leads to difficulties of the seroepidemiological interpretation. METHODS: We have studied the ability of urea as a chaotrope to select high-avidity antibodies in IgG ELISA, thus reducing low-avidity IgG cross-reactivity in serologically positive samples in both assays. RESULTS: Using 0.5M urea for diluting the sample efficiently defined leishmaniasis or double infections in high-avidity IgG ELISA and eliminated false-positive results. CONCLUSIONS: The use of a chaotropic diluting agent is useful for improving the specificity of Chagas disease and leishmaniasis immunoassays.