Results of Chagas' disease diagnosis show disagreement. The aim of this study was to compare commercial tests for Chagas' disease serodiagnosis in southern Brazil. A total of 161 samples were evaluated. Three enzyme-linked immunosorbent assays, one indirect hemagglutination and one indirect immunofluorescence were assessed. Trypomastigote excreted-secreted antigen-blot was a confirmatory method. From 161 samples, 65.84% were positive in all tests, while 34.16% presents mismatch result in at least one of the tests. All techniques tested presented false-positive and/or false-negative results as follows: Enzyme-linked immunosorbent assay 1 had more false-positive results (lower specificity), indirect immunofluorescence had the highest rate of false-negative results (lower sen sitivity), enzyme-linked immunosorbent assays had fewer false-negative results (higher sensitivity), while indirect hemagglutination showed no false-positive result (higher specificity). Knowing the characteristics of techniques make it possible to combine them and obtain more reliable diagnosis. Therefore, it seems useful to combine techniques for diagnosing this infection.

This study investigates the frequency of Torque teno virus (TTV) infection in 150 blood donors and 77 patients requiring haemodialysis in southern Brazil. Plasma samples were screened for TTV DNA using polymerase chain reaction (PCR). The prevalences of TTV among blood donors and patients requiring haemodialysis were 73.3% and 68.8%, respectively. The presence of TTV was correlated with age in the blood donors (p = 0.024). In haemodialysis patients, no association was found between TTV infection and the demographic parameters (age, sex and education), the duration of haemodialysis or a history of blood transfusion. This study is the first to evaluate the prevalence of TTV infection in Brazilian patients requiring haemodialysis.

Anticorpos antiTrypanosoma cruzi no cordão umbilical de 351 parturientes da Cidade de Pelotas, RS foram pesquisados a fim de investigar a prevalência da doença de Chagas em gestantes. Um (0,3%) caso foi identificado, não sendo detectada transmissão congênita. Salienta-se a importância da investigação da doença de Chagas em gestantes de zonas endêmicas ou provenientes destas.

Anti-Trypanosoma cruzi antibodies in the umbilical cord of 351 parturients in the city of Pelotas, Rio Grande do Sul were investigated to determine the prevalence of Chagas disease among pregnant women. One case was identified (0.3%), without detection of congenital transmission. This highlights the importance of investigating Chagas disease among pregnant women living in or originating from endemic areas.