Evaluation of the COBAS Amplicor HBV Monitor Assay and Comparison with the Ultrasensitive HBV Hybrid Capture 2 Assay for Quantification of Hepatitis B Virus DNA

Abstract

Performance characteristics of the COBAS Amplicor HBV Monitor test (Roche Diagnostics), which measures hepatitis B virus (HBV) DNA quantitatively, were evaluated and compared with the Ultrasensitive HBV Hybrid Capture 2 (HC2; Digene Corporation) assay. Linearity and within-run precision were assessed for both methods by using eight HBV DNA-positive samples serially diluted to obtain a range of <100 to 500,000 HBV DNA copies/ml and run in triplicate. Agreement between the methods was studied with 100 clinical samples.

Molecular Testing in the Diagnosis and Management of Chronic Hepatitis B

“…Excellent results (Ͼ97%) have been obtained in studies using samples from HBV-seronegative subjects (51,107,118,146,156). Problems with reproducibility at concentrations near the limits of quantification of Hybrid Capture II and Ultrasensitive Hybrid Capture II have been described (25 to 40% of samples originally determined to have 5,000 to 10,000 copies/ml were undetectable after repeat testing), suggesting that implementation of an equivocal zone should be considered for these assays (69). False-positive results (ranging from 1 to 3%) at the lower limit of quantification of VERSANT HBV DNA 3.0 have also been observed (39,124,156).…”

“…Significant variability in quantification among different assays can occur randomly (39,69) despite the standardization of reporting units and the finding of generally good correlation between different assays (56,77,122). Patients should therefore be monitored with a single assay.…”

Usefulness of in-house PCR methods for hepatitis B virus DNA detection

“…The COBAS Amplicor assay is a PCR-based, automated assay developed for the measurement of HBV DNA in serum, and this assay is reproducible, with a high degree of accuracy and precision in both intra-assay and inter-assay comparisons (Lopez et al, 2002). However, the COBAS Amplicor assay has the disadvantage of requiring diluted samples with high viral loads based on the serological profile of each patient, which is not a practical solution for all laboratories (Konnick et al, 2005).…”

“…A Cobas Amplicor instrument was used for PCR amplification, hybridization, and detection. According to the manufacturer, the Cobas Amplicor HBV Monitor test shows linearity from 2.0 × 10 2 (lower detection limit) to 2.0 × 10 5 HBV DNA copies/mL (Konnick et al, 2005;Shi et al, 2008). Samples with >200,000 HBV DNA copies/mL in the Amplicor assay were diluted 1:900, 1:27,000, or 1:810,000, as necessary, in HBV DNA-negative normal human serum (NHS), and the diluted material was re-extracted, amplified, and analyzed to obtain a result within the analytical measurement range of the Amplicor assay.…”

Molecular Diagnostics for the Detection and Characterization of Microbial Pathogens

“…This technology has also been used for the detection of cytomegalovirus, hepatitis B virus, Neisseria gonorrhoeae, and Chlamydia trachomatis [45][46][47]. Although signal amplification assays that do not employ direct microscopy are often not as sensitive as nucleic acid amplification, some have shown the contrary [44,48].…”