Evaluation of a new assay for HBV DNA quantitation in patients with chronic hepatitis B

Background: The Amplicor™ HBV Monitor Test for quantitative determination of serum hepatitis B virus (HBV) DNA has recently been introduced. This assay is based on PCR and a non-radioactive hybridization and detection system on microwell plates.

Objective: The performance of the Amplicor™ HBV Monitor Test was evaluated in a routine diagnostic laboratory. The Amplicor™ HBV Monoitor assay was compared to the Digene Hybrid Capture™ System HBV DNA assay for the quantitation of HBV in patient sera.

Study design: Sensitivity and reproducibility were determined with 10-fold dilution series of two Eurohep HBV reference plasma specimens. Furthermore, 196 sera from 14 children with chronic HBV infection and interferon therapy were tested with both assays.

Results: The detection limit was found to be 10³ copies/ml with the Amplicor™ PCR assay compared to 10⁶ to 10⁷ copies/ml with the Digene™ hybridization assay. Both assays were quasi-linear over the measurable ranges. The new PCR assay proved to be very reliable. With the Amplicor™ PCR assay, 26.2% of the HBV DNA-positive clinical samples were found between 10³ and 10⁷ copies/ml and all of them tested below the detection limit with the hybridization assay.

Conclusion: The Amplicor™ HBV Monitor Test shows excellent sensitivity and provides a valuable tool for the detection of HBV DNA in serum. It can be used for recognizing those patients who might benefit from antiviral therapy, for evaluation of the efficacy of anti-HBV therapy, and for validation of blood products.