Quantitative detection of hepatitis B virus DNA in human sera by branched-DNA signal amplification.

Serum samples from 116 patients with hepatitis B surface antigen (HBsAg), from 7 patients without detectable HBsAg and from 71 healthy blood donors were tested by a branched DNA signal amplification (bDNA) method. Hepatitis B virus (HBV) DNA was detected in 39 (34%) of the 116 samples with HBsAg, including 19 (70%) of the 27 patients who were also positive for hepatitis B e antigen (HBeAg). In contrast, one of the 7 patients without HBsAg and none of the 71 blood donors were positive for HBV DNA. The titers of serum HBV DNA did not correlate with the serum alanine aminotransferase levels. All the samples positive by the bDNA assay were positive by the polymerase chain reaction (PCR). However, 59% of the PCR-positive samples were bDNA-negative. None of the PCR-negative samples was positive by the bDNA method. Although the sensitivity of bDNA method is not entirely satisfactory, it showed excellent specificity and reproducibility. Thus it may be considered as an alternative for quantitative detection of HBV DNA in serum samples of patients with relatively high titers of HBV viremia.