Evaluation of a novel fully automated real-time PCR assay for hepatitis B virus DNA quantification / 中华检验医学杂志

ABSTRACT

Objective To evaluate the analytical performance of a novel HBV DNA assay based on automated DNA extraction and real-time fluorescence quantitative PCR .Methods Analytic verification studies.Accuracy and lower limit of detection were assessed by determining a panel of HBV standard plasma of WHO.HBV standard plasma (genotype A, B, C and D) at 6 different concentrations were measured 18 times to evaluate precision and reproducibility .Pseudo-viral particles at high HBV DNA concentration were serially diluted to assess linear range .One hundred and forty-four clinical specimens were quantified for HBV DNA so as to evaluate the correlation between the new test and COBAS ? system. Results Quantification of HBV standard plasma showed acceptable accuracy , with each deviation between observed and expected values within ±0.35 lg IU/ml (-0.17-0.32 lg IU/ml).Intra-assay coefficients of variation ( CV) for genotype A , B, C and D were 3.87% -6.32%, 0.45% -14.68%, 0.16% -8.36% and 0.64%-13.01%respectively, and the inter-assay CV were 5.67%-9.69%, 1.28%-15.68%, 0.36%-9.05%and 1.69%-13.65%, separately.Linearity assessment exhibited an excellent dynamic range of linear quantification from 20 to 1.0 ×1010 IU/ml ( r =0.998, P <0.001 ) .And the satisfactory results obtained at 3 levels of HBV DNA concentration (10, 20, 50 IU/ml, respectively) confirmed the claimed lower limit of detection with 5/5 detectable rate at 20 IU/ml.Furthermore, good correspondence was observed between the new HBV DNA assay and the COBAS ? system with 100% ( 144/144 ) qualitative coincidence and significant correlation based on 104 positive data ( r=0.984, P<0.000 1).Conclusions The novel fully-automated real-time PCR assay displayed good analytical and clinical performance for highly sensitive detection of HBV DNA.It was well suited for monitoring antiviral responses as well as drug resistance according to current clinical practice guidelines for the management of chronic HBV infection .