Anti-HBc & HBV-DNA detection in blood donors negative for hepatitis B virus surface antigen in reducing risk of transfusion associated HBV infection.

ABSTRACT

BACKGROUND & OBJECTIVE: Though sensitive screening assays for detection of hepatitis B virus surface antigen (HBsAg) are available, occasional cases of post-transfusion hepatitis B virus infection (PTH) still occur. The present study was undertaken to assess the prevalence of anti-hepatitis B core (anti-HBc) positivity and presence of HBV-DNA in serum sample of healthy blood donors negative for both HBsAg and anti-HCV antibody in Shiraz, Iran. Since anti-HBc detection is not mandatory in Iran, we evaluated whether anti-HBc detection could be adopted as a screening assay for safety of donated blood. METHODS: Two thousands serum samples negative for both HBsAg and anti-HCV collected from healthy blood donors were tested for the presence of anti HBc antibody. All samples positive for anti-HBc antibody were then investigated for determination of anti-HBc titre, anti-HBs titre, HbeAg and anti-HBe antibody by enzyme immunoassay (EIA). Every sample that tested negative for HBsAg but positive for anti-HBc alone or in combination with other serological markers was also examined for the presence of HBV-DNA by polymerase chain reaction (PCR). RESULTS: Of the 2000 samples tested, 131 (6.55%) blood samples were found to be positive for anti- HBc. HBV DNA was detected among 16 of 131(12.2%) anti-HBc positive specimens. Further, there was an association between the titration of anti-HBc antibody and the intensity of expected PCR product band. The liver function test results were all in normal range except in 4 of 16 HBV-DNA positive subjects. The mean levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in HBV-PCR positive subjects were 14 IU/l and 23.7 IU/l respectively. INTERPRETATION & CONCLUSION: Anti-HBc antibody should be tested routinely on blood donors volunteers and if the sample found positive regardless of anti-HBs titre, the blood should be discarded. Further testing for HBV-DNA would be appropriate to follow up the donor for HBV infection.