Evaluation of a Hepatitis C Virus Core Antigen Assay in Plasma and Dried-Blood Spot Samples

This study evaluated the analytical performance of HCV core antigen (HCVcAg) detection in plasma and dried blood spot (DBS) samples. Paired plasma and venous DBS samples were prepared from remnant diagnostic samples. Plasma HCV RNA was quantified by AmpliPrep/COBAS Taqman (Roche) and HCVcAg measured by ARCHITECT HCV Ag (Abbott Diagnostics). Sensitivity and specificity for HCVcAg (>3 fmol/L) at two HCV RNA thresholds (≥15 IU/mL and ≥3,000 IU/mL) were calculated. Of 120 paired samples tested, 25 had non-quantifiable HCV RNA and 95 quantifiable HCV RNA. The median HCV RNA level in plasma was 5.6 log10 IU/mL (IQR: 5.2, 6.2). The median HCVcAg level for plasma and DBS was 2.3 log10 fmol/L (IQR: 0.1, 3.1) and 1.1 log10 fmol/L (IQR: 0.0, 1.9), respectively. For diagnosing HCV RNA ≥3,000 IU/mL, the sensitivity and specificity of HCVcAg in plasma was 97.7% (95%CI: 91% to 100%) and 100% (95%CI: 87% to 100%), respectively. The sensitivity and specificity of HCVcAg in DBS was 88.6% (95%CI: 80% to 94%) and 97% (95%CI: 82% to 100%), respectively. The data from this study demonstrate a good sensitivity and specificity of HCVcAg in plasma when HCV RNA>3,000 IU/mL. The level of HCVcAg quantified in plasma was higher than that in DBS.

Source: The Journal of Molecular Diagnostics - July 10, 2018 Category: Pathology Source Type: research