Performance evaluation of the access anti-HCV assay on the DxI 9000 immunoassay analyzer

Objectives This study evaluated the clinical and analytical performances of the Access anti-HCV assay on the DxI 9000 Access Immunoassay Analyzer (hereafter DxI 9000). Materials and methods Diagnostic specificity and sensitivity of the Access anti-HCV assay were evaluated by comparing Access assay results to final anti-HCV sample status determined using a CE marked anti-HCV comparator assay and confirmatory immunoblot for positive and discrepant results. Performance of potential cross-reacting samples, sensitivity on seroconversion panels, and imprecision were also evaluated. Results Diagnostic specificity was 99.74% (95% CI 99.58 – 99.84%) on 5852 anti-HCV negative blood donor samples and 99.00% (98.35 – 99.39%) on 1497 anti-HCV negative hospitalized patient samples. Diagnostic sensitivity was 99.81% (98.90 – 99.97%) on 513 immunoblot-confirmed anti-HCV positive samples and 100.00% (98.92 – 100.00%) on an HCV genotyped subset of 353 samples. Cross reacting samples had specificity of 100.0% (99.02 – 100.00%) on 390 anti-HCV negative samples and sensitivity of 100.0% (97.50 – 100.00%) on 150 anti-HCV positive coinfection samples. Sensitivity on seroconversion panels showed mean first day of detection less than one day difference between Access anti-HCV and a comparator assay. Maximum patient sample reproducibility had a coefficient of variance (CV) of 10.1% on positive samples and 0.055 S/CO standard deviation (SD) on negative samples. Conclusions Access anti-HCV demonstrated excellent clinical and analytical performance comparable to other current CE-marked anti-HCV assays and provides a valuable addition to the DxI 9000 serological menu.