Comparison of Molecular Biologic Methods for Detecting HBV-DNA in the Sera which Showed Both Hepatitis B Surface Antigen and Antibody Positivity / 대한임상병리학회지

ABSTRACT

BACKGROUND: Serologic markers are used to screen and diagnose the hepatitis B virus infection. In endemic area of hepatitis B, the coexistence of HBsAg and anti-HBs was frequently observed. This finding is unusual and difficult to interpret. In this study, we performed three molecular biologic assays-polymerase chain reaction (PCR), chemiluminescent molecular hybridization assay (CMHA), branched DNA (bDNA) nucleic acid hybridization assay- to detect HBV-DNA in the sera which showed both HBsAg and anti-HBs positivity. To define the patients` exact clinical conditions, we analysed the characteristics of the patients according to their diagnoses, other serologic markers and clinical findings. METHODS: HBsAg and anti-HBs were detected by EIA (Enzygnost, Behringwerke, Germany) from clinical specimens of Yonsei University College of Medicine Severance Hospital collected In the period between January 1996 and December 1996. Eighty three specimens from Severance Hospital and twenty two specimens from Health Care Center were randomly selected and were subjected to HBV PCR, HBV CMHA and HBV bDNA assay for the presence of HBV-DNA. RESULTS: The patients were arbitrarily divided into 4 groups on the basis of the optical density values of enzyme immunoassay results. Group I (high HBsAg and high antral-HBs) consisted of 6 cases; group II (high HBsAg and low anti-HBs) consisted of 70 cases, group III (low HBsAg and high anti-HBs) consisted of 1 case; group IV (low HBsAg and low antral-HBs) consisted of 6 cases. Among 83 cases, the positive rate was 51.8% (43 cases) using PCR method, 53.0% (44 cases) using CMHA, 60.2% (50 cases) using bDNA assay. HBeAg and anti-HBc IgM were helpful to predict the presence of HBV-DNA in the sera. CONCLUSIONS: More than half of the patients who showed both HBsAg and anti-HBs positivity were positive for HBV-DNA by molecular biologic methods. In contrast, no one whose serologic markers with only anti-HBc positivity with out HBsAg and anti-HBs positivity showed HBV-DNA positive in the sera from Health Care Center. Taken together, the management and follow-up of the patients of both HBsAg and anti-HBs positivity could be greatly aided by combined adoption of any one molecular biologic assay of HBY-DNA with other serologic markers such as HBeAg and anti-HBc IgM.