MULTICENTER EVALUATION OF THE COBAS AMPLICOR HCV ASSAY, AN INTEGRATEDPCR SYSTEM FOR RAPID DETECTION OF HEPATITIS-C VIRUS-RNA IN THE DIAGNOSTIC LABORATORY

The benefits shown by the recent introduction of PCR for the in vitro diagnosis of hepatitis C virus (HCV) infection has prompted the develo pment of standardized, ready-to-use assays that can be implemented in routine clinical laboratories, We have evaluated the clinical performa nce of COBAS AMPLICOR HCV (COBAS), the first instrument system that al lows the automation of HCV RNA amplification and detection, to determi ne its performance in the routine laboratory setting, More than 2,000 specimens collected at five centers mere analyzed in parallel by the C OBAS and the manual AMPLICOR HCV (AMPLICOR) tests, and the results wer e compared with the results for biochemical and serological markers of HCV. In this study the two PCR systems showed the same accuracy, with a concordance rate of 99.8%. As expected, the correlation between ser ology and PCR was not absolute because the presence of anti-HCV antibo dies may be associated with a latent or past infection, On the other h and, if the presence of confirmed anti-HCV antibodies and elevated ala nine aminotransferase levels are taken as the ''gold standard,'' indic ating an active, ongoing infection, the COBAS and AMPLICOR tests show high and comparable sensitivities (100%) and specificities (98%), with positive and negative predictive values of 100 and 97%, respectively, During the study no false-positive reactions were detected, The use o f an internal control allowed the identification of inhibitory substan ces that prevented amplification for 0.3 and 0.4% of samples tested by the COBAS and AMPLICOR tests, respectively, Compared to the manual sy stem, the COBAS system allowed a significant reduction of hands-on tim e and could improve the overall laboratory work how In conclusion, the se results support the use of the COBAS and AMPLICOR tests for the mol ecular diagnosis of active HCV infections.