Rapid negativization of serology after treatment with benznidazole for Chagas disease in a group of Colombian schoolchildren

The purpose of this study was to assess the efficacy and safety of benznidazole for the treatment of Chagas disease in a group of infected but asymptomatic Colombian schoolchildren. A total of 1,643 schoolchildren were screened for IgG antibodies against Trypanosoma cruzi using an Elisa test. Serum samples were taken from positive children to confirm seropositivity by IFAT and Elisa in a double blind screening. Only children with positive results in both laboratories were considered as infected. A number of seronegative children from the same region, whose age and sex distribution matched that of the infected children, was established as a control group. Children in both groups were submitted to a thorough physical examination and a standard EKG. Treatment was carried out with benznidazole at a daily dose of 5 mg/kg weight during 60 days. Clinical follow-up visits were done every 2 weeks during treatment. Five months after completing treatment serum samples were taken to compare the pre-treatment with the post-treatment titers. The prevalence of infection was 92/1,643 (5.6%); 48 children completed treatment; mild headache was present in 7 patients (14.6%), skin rash in 3 (6.25%), relative leukopenia in 2 (4.2%) and anemia in 1 (2.1%). A negative seroconversion was observed in 34/36 (94.4%) children 5 months after finishing treatment.