Prospective multicenter clinical evaluation of AMPLICOR and COBAS AMPLICORhepatitis C virus tests

We conducted a multicenter clinical evaluation of the second versions of th e manual AMPLICOR and the semiautomated COBAS AMPLICOR tests for hepatitis C virus (HCV) RNA (Roche Molecular Systems, Inc., Pleasanton, Calif.). The performance characteristics of these HCV RNA tests for diagnosis of active viral infection were determined by comparison to anti-HCV serological test results, alanine aminotransferase levels, and liver biopsy histology result s. A total of 878 patients with clinical or biochemical evidence of liver d isease were enrolled at four hepatology clinics. A total of 1,089 specimens (901 serum and 188 plasma) were tested with the AMPLICOR test. Sensitivity compared to serology was 93.1% for serum and 90.6% for plasma. The specifi city was 97% for serum and 93.1% for plasma. A total of 1,084 specimens (89 6 serum and 188 plasma) were tested with the COBAS test. Sensitivities for serum and plasma were the same as with the AMPLICOR test. The specificity w as 97.8% for serum and 96.6% for plasma. Of the 69 specimens with false-pos itive and false-negative AMPLICOR test results relative to those of serolog y, alternative primer set (APS) reverse transcription (RT)-PCR analysis sho wed that the AMPLICOR test provided the correct result relative to the spec imens containing HCV RNA in 64 (92.7%) specimens. Similarly, 66 of 67 (98.5 %) false-positive and false-negative COBAS test results were determined to be correct by APS RT-PCR analysis. There were no substantive differences in clinical performances between study sites, patient groups, specimen types, storage conditions (-20 to -80 degreesC versus 2 to 8 degreesC), or antico agulants (EDTA versus acid citrate dextrose) for either test. Both tests sh owed > 99% reproducibility within runs, within sites, and overall. We concl ude that these tests can reliably detect the presence of HCV RNA, as eviden ce of active infection, in patients with clinical or biochemical evidence o f liver disease.