What technique should be used for routine detection and quantification of HBV DNA in clinical samples?

Detection of hepatitis B virus (HBV) DNA in serum allows monitoring of HBV replication and assessing responses to antiviral treatment. HBV DNA quantification measures virus replication and can be used as a prognosis indicator of. liver disease and an index of response to antiviral drugs. The aim of this study was to compare the performances of three HBV DNA detection and/or quantification techniques for assessing HBV replication. Three hundred unselected sera with a request for HBV DNA detection and quantification were tested with a molecular hybridisation technique without amplification (Digene Hybrid-Capture(TM), Murex Diagnostics Ltd), a signal amplification assay based on branched DNA technology (Quantiplex(TM) HBV DNA, Chiron Diagnostics), and an 'in-house' qualitative, non quantitative target amplification assay based on the polymerase chain reaction (PCR) with primers located in the S gene of the HBV genome. Hybrid-capture and branched DNA gave concordant results in 278 cases (93%), In the 128 samples positive by both assays, DNA titres in pg/ml were related significantly (r = 0.70, P < 0.0001), but branched DNA titres increased more rapidly than hybrid-capture titres when the amount of HBV DNA in the sample increased. Twenty-two sera (7%) were negative by hybrid-capture, but positive in branched DNA (detection rate gain: 15%). In these 22 patients, DNA titres were low, HBsAg was present in all instances and alanine aminotransferase activity was elevated in 18 patients (82%); HBeAg was present in seven patients (32%) and anti-HBe antibodies in 18 patients (82%); liver biopsy, undertaken in 18 patients, revealed chronic active hepatitis in all instances, associated with cirrhosis in eight cases. Qualitative, non-quantitative HBV DNA PCR was positive in 75 (50%) of the 150 hybrid-capture-negative, branched DNA-negative samples, including a significant proportion of patients without evidence of ongoing HBV-related liver disease. The results show that in general, the branched DNA assay detects HBV DNA in more patients than hybrid-capture and that this improved detection rate is relevant clinically and genome equivalents/ml are preferred to pg/ml to quantify HBV DNA in clinical specimens and finally qualitative, non-quantitative polymerase chain reaction can detect HBV DNA in patients without evidence of active HBV-related liver disease. This study emphasizes the need for more sensitive, universally standardised quantitative HBV DNA assays and for the definition of clinically relevant cutoffs with these assays. (C) 1997 Elsevier Science B.V.