Performance evaluation of the Vitros anti-hepatitis C virus antibody assay for use in clinical laboratories

Objectives: We evaluated the performance of Vitros anti-HCV assay. Design and methods: Precision performance was assessed for 20. days. A total of 1011 sera were tested for anti-HCV with Vitros and Elecsys assays. Specimens positive for any of the two assays were retested with Architect assay. Discrepant results were evaluated with recombinant immunoblot assay (RIBA) and HCV RNA quantification. Results: Total imprecision of Vitros assay was 11.6% and 3.3% CV for negative and positive QC. Among the 1011 sera, 17 showed discrepant results between the three assays. Six were positive and three negative for RIBA. HCV RNA was not detected from all discrepant cases. Sensitivity and specificity were 99.5% and 99.5% for the Vitros, and 100.0% and 99.9% for the Elecsys assay. Conclusions: Sensitivities and specificities of the anti-HCV assays were sufficiently high for use in clinical laboratories, but retesting of weak positive results may be necessary.