Sensitivity of a modified version of the ARCHITECT Anti-HCV test in detecting samples with immunoblot-confirmed, low-level antibody to hepatitis C virus.

BACKGROUND AND OBJECTIVES

Compliance with current regulations regarding the prevention of hepatitis C virus (HCV) transmission in the blood transfusion setting requires the use of sensitive assays for HCV antibody (anti-HCV) detection, which should, ideally, identify any donor having had prior contact with the virus. Therefore, low-level anti-HCV positive blood units should be detected by the screening assays, even those reflecting a past and resolved infection. To assess the sensitivity of two versions of an automated chemiluminescent microparticle immunoassay (CMIA) for anti-HCV screening (ARCHITECT Anti-HCV), 113 single serum samples containing low levels of anti-HCV, assessed by two immunoblot tests, were selected from 3686 samples received for confirmation of HCV infection by a reference laboratory over a 2-year period.

MATERIALS AND METHODS

The panel included 17 samples with HCV RNA detected by the polymerase chain reaction (PCR) and 96 PCR negative samples with either positive or indeterminate (anti-Core and anti-NS3 alone) results by immunoblot.

RESULTS

All but 13 specimens (100/113, 88.5%) were detected by the current version of the ARCHITECT Anti-HCV assay and 10 additional samples (110/113, 97.3%) tested positive in a modified version of the test.

CONCLUSION

The results showed that the modification introduced in the ARCHITECT Anti-HCV assay achieves a significant sensitivity improvement including samples with low-level anti-HCV which are either PCR positive or negative.