Parasitological cure and clinical benefits of benznidazole treatment in patients from the Jequitinhonha Valley, MG, Brazil, with recent chronic infection by Trypanosoma cruzi II

BACKGROUND The treatment of the early chronic phase of Chagas disease (CD) may result in high rates of parasitological cure, which may be associated with clinical benefits. OBJECTIVES To evaluate children with CD from the Jequitinhonha Valley, MG, Brazil, treated with benznidazole (BZ), employing classic and alternative methodologies. METHODS Before and after treatment, nine individuals were examined by haemoculture, polymerase chain reaction (PCR), conventional enzyme-linked immunosorbent assay (ELISA), electrocardiogram, echocardiogram, and thoracic and gastrointestinal X-ray. Eight individuals were in the indeterminate clinical form of CD, and one was in the mild cardiac form. After treatment, all individuals were re-evaluated periodically for 4-26 years using the same methodologies cited and anti-live trypomastigotes antibodies by flow-cytometry-FC-ALTA and quantitative PCR (qPCR). FINDINGS The cure rate by the classic cure criteria was 33.33%. By the alternative cure criteria using FC-ALTA and qPCR, the rates of cure were 50% and 78%, respectively. Post-treatment clinical evaluations revealed stability in 5/9 and discrete clinical evolution in 4/9 individuals. MAIN CONCLUSIONS It was demonstrated the effectiveness of BZ treatment in recent chronic infections of CD with low or higher rates of parasitological cure according to the cure criterion used after long-term follow-up. The clinical status of the individuals remained stable or evolved slowly, suggesting clinical benefits from BZ treatment.