Detection of Trypanosoma cruzi and Treatment Monitoring by PCR from Dried Blood Spot Samples in Children

Abstract

Background: Parasitic infections by Trypanosoma cruzi (T. cruzi) are frequent in children from endemic areas. Specific therapies have been successfully used in pediatric populations to treat this disease. T. cruzi diagnosis should be optimized and become available for any clinical environment.

Objective: To study T. cruzi prevalence in children from an area of active transmission and carry out a posttreatment follow-up. To verify the feasibility of detecting DNA of T. cruzi from dried blood spot.

Methods: We analyzed presence of T. cruzi in 78 Aboriginal children (Toba community) that attended to a rural school of Chaco province, Argentina. Serum and whole blood (dried blood spot) were assessed by means of serological techniques and PCR. Positive children received Benznidazole. Diagnosis and post treatment follow-up of T. cruzi infection were performed.

Results: The serology assay showed infection in 34 of 78 (43.5%) children studied; PCR was positive in 5/34, displaying parasitemia. Serology remained positive in 28/28 children 120 days post-treatment, while PCR was positive in 18/28 (6/34 children were lost in follow-up). No adverse effects during the treatment were reported.

Conclusions: We were able to establish T. cruzi prevalence in the studied population and also to prove the usefulness of dried blood spot for T. cruzi detection using PCR in isolated areas. This method allowed us to verify early treatment failure. Possible causes of this failure are discussed below.