DISCUSSION
Chagas disease, chronic Chagas disease
CHAGAS DISEASE, CHRONIC INFECTION, CHRONIC CHAGAS DISEASE
Establishing the efficacy of antitrypanosomal therapy in patients with Chagas disease using the currently accepted criterion of treatment response is challenging. In Chagas disease, it is widely acknowledged that treatment success is difficult to measure with the current diagnostic tools because the parasites are highly antigenic and produce a strong antibody response that persists even after successful antiparasitic treatment (In this study, we evaluated seronegative conversion in pediatric patients with Chagas disease followed over a period of 4 years posttreatment. The results confirm the effectiveness and safety of nifurtimox administered over 60 days in pediatric patients, from newborn to 17 years of age, with Chagas disease. The superior seronegative conversion attributable to the 60-day nifurtimox treatment regimen compared with historical placebo control that was demonstrated at 12 months after the end of treatment (Conversion of serological response to negative measured by conventional serological testing remains the gold standard for monitoring the posttherapeutic response in Chagas disease (The previously reported results of the first year of posttreatment follow-up in this prospective trial (Up to two-thirds of people with Chagas disease never develop signs or symptoms, even during the chronic infection phase (No AEs considered at least possibly related to nifurtimox treatment or caused by procedures required by the protocol were reported during the further 3 years of observation that followed CHICO (The main limitation of this study is the lack of a prospective untreated control group, which would not have been ethical to include because the current standard of care is the treatment of all infected children. The primary outcomes of treatment were compared with an estimated 0% seronegative conversion rate from historical placebo data obtained from a previously published clinical trial in 6- to 12-year-old children with early chronic Chagas disease treated with benznidazole and followed for 4 years (