Early antiparasitic treatment prevents progression of Chagas disease: Results of a long-term cardiological follow-up study in a pediatric population

Background Chagas disease (CD), a parasitic disease caused by Trypanosoma cruzi . Parasite persistence is crucial in the development and progression of Chagas cardiomyopathy that occurs in 30% of untreated patients. Methods and findings A cohort of 95 CD treated children, with at least 6 years post-treatment follow up, was evaluated. Median after treatmeant follow-up was 10 years. At the time of the last visit a group of non infected subjects were also included as a control for cardiological studies. During follow-up, the majority of treated subjects 59/61 (96%) achieved negative parasitemia by qPCR at the end of treatment. A decrease in T. cruzi antibodies titers were observed and seroconversion by two conventional serology tests (IHA, ELISA) occurred in 53/95 (56%). Holter showed alterations in 3/95 (3%) of treated patients: isolated ventricular extrasystoles and nocturnal sinus bradycardia (one patient); asymptomatic and vagal related 1st and 2nd degree AV block (one patient); and complete right bundle branch block (cRBBB) (one patient). Only the last one is probably related to CD involvement. 2D speckle tracking echocardiography was conducted in 79/95 (83%) patients and no alterations in myocardial contractility were observed. In the non infected group Holter evaluations showed similar non pathological results in 3/28 (10%) of subjects: isolated ventricular premature beats (2 patients); asymptomatic 2nd degree AV block with Wenckebach sequences during night time (one patient). 2D speckle tracking echocardiography was conducted in 25/28 (89%) with no alterations. Conclusions After long term follow-up of a cohort of treated children for CD, a good parasiticidal treatment effect and a low incidence of cardiological lesions, related to Chagas disease, were observed. These results suggest a protective effect of treatment on the development of cardiological lesions and strengthen the recommendation of early diagnosis and treatment of infected children. Trial registration ClinicalTrials.gov NCT04090489 . Author summary If left untreated, CD evolves into a chronic oligosymptomatic infection that can progress to cardiac complications in 30% of patients after several years. It is known that the main early marker of cardiac involvement are alterations in the conduction system. There are few studies of long-term after treatment cardiological evolution which have assessed the clinical effectiveness of treatment. The rationale for CD treatment is to avoid the development of cardiological complications. The parasiticidal effect of treatment has been demonstrated but its clinical effectiveness in preventing cardiac involvement requires long term follow-up. In our long term follow-up study of treated children, we observed the preventive effect on cardiac lesions by treatment with benznidazole or nifurtimox. This intensifies the need for early diagnosis and treatment to prevent the development of long term complications observed in CD.