Which serological tests are recommended for confirming a diagnosis of Chagas disease in primary care settings?

In primary care settings, the confirmation of a diagnosis of Chagas disease relies primarily on serological testing using at least two different assays based on distinct antigenic principles to improve diagnostic accuracy. The recommended serological tests include enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence assay (IFA) or indirect hemagglutination assay (IHA), which are widely used for initial screening and confirmation respectively NICE NG95.

These tests detect antibodies against Trypanosoma cruzi, the causative agent of Chagas disease, and are essential because parasitological methods have low sensitivity in chronic infection stages typically encountered in primary care. Confirmatory diagnosis requires concordant positive results from two different serological tests to reduce false positives NICE NG95.

Recent literature supports this approach and highlights the utility of multiplex immunoassays that can simultaneously detect multiple antibody specificities, potentially improving early detection and monitoring of antibody decline post-treatment Saade et al. 2024. However, these multiplex assays are more commonly used in research or specialist settings rather than routine primary care.

Overall, the integration of guideline recommendations and recent evidence suggests that primary care should continue to use at least two conventional serological tests (e.g., ELISA plus IFA or IHA) for diagnosis confirmation, while being aware of emerging multiplex immunoassays that may enhance diagnostic precision in the future NICE NG95; Saade et al. 2024.