Serological screening of blood donors with low indexes of infection, including hepatitis C virus (HCV), accounts for a substantial percentage of false-positive results with consequent loss of non-infected blood components. The aim of this study was to evaluate the occurrence of hepatitis C using confirmatory tests for blood donors with positive or inconclusive results at Hemocentro Regional de Uberaba (HRU). Confirmatory tests were performed by the detection of HCV RNA in plasma using qualitative RT-PCR. The study was carried out from 1992 to 2005 for 171,027 blood donors, 24.3% first-time and 75.7% repeat donors. The ineligibility rate to HCV was 0.3% (561 donors) with 52.9% of them being first-time donors and 47.0% repeat donors with prevalences of 0.5% and 0.2% respectively (p<0.0001). The rate of inconclusive results was significantly higher among repeat donors (p=0.0214). Ninety-eight samples were subjected to qualitative PCR and only 34.7% (34) had positive results, with a significantly lower rate of positiveness for repeat donors (p = 0.0184) and almost a threefold lower rate of inconclusive results for the same donors. These results showed that, for a large number of donors with positive and inconclusive tests for anti-HCV, the infection was not confirmed. We concluded that serological ineligibility for hepatitis C of donors at HRU was not always associated with the presence of viral infection.
Serological screening; blood donors; hepatitis C; confirmatory test
