Clinical Performance of the Elecsys HCV Duo Immunoassay Compared with a Standard-of-Care Algorithm Using Alinity Anti-HCV Screening and HCV RNA Confirmation

Background/Objectives: The Elecsys HCV Duo immunoassay simultaneously detects HCV core antigen (HCV Ag) and anti-HCV antibodies in a single sample. We evaluated its clinical performance against a standard-of-care reference algorithm of anti-HCV antibody and HCV RNA testing.

Methods

We retrospectively analyzed 1332 residual serum or plasma samples tested with reference HCV RNA assays and the Alinity i Anti-HCV assay. Samples were classified as reference-positive, indicating current or past HCV infection (n = 166; 88 RNA+/Ab+ with active infection and 78 RNA−/Ab+ with resolved or treated infection), or reference-negative (n = 1166; RNA−/Ab−), including 1000 randomly selected blood donor samples. All specimens were tested with the Elecsys HCV Duo (cobas® e 801, Roche Diagnostics). Positive and negative percent agreements (PPA and NPA) were calculated against the combined reference standard. Results were further analyzed by infection status and viral load. No HCV RNA+/anti-HCV− (window-period) specimens were available.