In-house ELISA method to analyze anti-Trypanosoma cruzi IgG reactivity for differential diagnosis and evaluation of Chagas disease morbidity

introduction: the goal was to develop an in-house serological method with high specificity and sensitivity for diagnosis and monitoring of chagas disease morbidity. methods: with this purpose, the reactivities of anti-t. cruzi igg and subclasses were tested in successive serum dilutions of patients from berilo municipality, jequitinhonha valley, minas gerais, brazil. the performance of the in-house elisa was also evaluated in samples from other relevant infectious diseases, including hiv, hepatitis c (hcv), syphilis (syp), visceral leishmaniasis (vl), and american tegumentary leishmaniasis (atl), and noninfected controls (ni). further analysis was performed to evaluate the applicability of this in-house methodology for monitoring chagas disease morbidity into three groups of patients: indeterminate (ind), cardiac (card), and digestive/mixed (dig/mix), based on their clinical status. results: the analysis of total igg reactivity at serum dilution 1:40 was an excellent approach to chagas disease diagnosis (100% sensitivity and specificity). the analysis of igg subclasses showed cross-reactivity, mainly with ni, vl, and atl, at all selected serum dilutions. based on the data analysis, the ind group displayed higher igg3 levels and the dig/mix group presented higher levels of total igg as compared with the ind and card groups. conclusions: these findings demonstrated that methodology presents promising applicability in the analysis of anti-t. cruzi igg reactivity for the differential diagnosis and evaluation of chagas disease morbidity.