Background: In settings such as needle-stick injuries or intravenous drug abuse, immediate knowledge of the anti-hepatitis C virus (HCV) serostatus instead of waiting for the results of a laboratory-based test can be important to guide further medical procedures and appropriate hygienic advises. Thus, a rapid on-site anti-HCV test was evaluated in daily clinical routine and compared with a laboratory-based certified assay.
Patients and methods: Ten microliters of serum or EDTA whole blood was analyzed using a chromatographic immunoassay (Toyo anti-HCV test). Results were available on-site 5-15 min after sample centrifugation. The Architect anti-HCV test served as a reference method.
Results: Sera of 189 patients were analyzed (without HCV infection: n=105; HCV infection: n=84). The assay was evaluable in 185 cases (98%). The sensitivity and specificity were 99 and 88%, respectively. With EDTA whole blood, the test was evaluable in 47/52 samples (90%). Forty-six of 47 evaluable EDTA tests were concordant with serum results. The one HCV patient with an unevaluable serum test was diagnosed correctly with the EDTA sample.
Conclusion: The rapid chromatographic anti-HCV immunoassay has limited specificity, which impairs clinical practicability. A positive result warrants re-evaluation with a certified serologic assay.