Anti-HCV reactive blood donors: clinical and epidemiological factors associated with false-reactive results.

BACKGROUND: In certain clinical settings, false-reactive anti-hepatitis C virus (HCV) results are rare because the majority of persons being tested have evidence of liver disease and the specificity of the screening assays is high. However, among healthy populations, such as blood donors, mainly in regions with a low prevalence of HCV infection, this situation does occur. In this study, we sought to assess clinical, epidemiological, and laboratory characteristics of blood donors with false-reactive anti-HCV screening tests.

METHODS: This retrospective cross-sectional study included 537 anti-HCV reactive blood donors referred to a tertiary care centre for liver diseases.

RESULTS: The mean age was 36.5+/-11.2 years and 71.8% were men. Blood donors of older age (P=0.010), history of alcohol abuse (P=0.039), past transfusion (P<0.001), intravenous drug use (P<0.001), and with antibody against core antigen of hepatitis B virus reactivity (P=0.003) were less likely to have a false-reactive anti-HCV result. By multivariate analysis, only the absence of parenteral risk factors (prior transfusion and intravenous drug use) was independently associated with false-reactive anti-HCV tests.

CONCLUSION: Blood donors with reactive anti-HCV screening tests with no risk factors for parenterally acquired HCV infection are more likely to present with false-reactive results.