Background: Hepatitis C virus (HCV) has a global prevalence of almost 60 million cases, and the numbers are on the rise.¹ Timely and accurate HCV testing is important for providing information and initiating treatment as well as for reducing HCV infections.² Recently, we developed a fully automated, low sample volume (3 µL) anti-HCV assay for use on the new DxI 9000 Immunoassay analyzer. This evaluation assessed within-laboratory imprecision, reproducibility, and analytical specificity, as well as agreement with the ARCHITECT Anti-HCV assay.

Methods: 20-day imprecision and five-day reproducibility studies were performed based on CLSI EP05-A3. Analytical specificity was evaluated using CLSI EP07 for cross-reactivity and interference studies. Each potential cross-reactant was represented by ten specimens and included specimens from viral infections, autoimmune diseases, non-viral liver diseases, post-vaccination patients, and pregnant women. For interference studies, known concentrations of potential interferents were added to patient samples and compared with controls. A concordance study was performed between Beckman Coulter’s Access Anti-HCV and Abbott’s ARCHITECT Anti-HCV assays using samples from hospitalized patients and presumed HCV antibody-positive patients. Supplementary testing using immunoblot and/or HCV PCR was also performed, as necessary, to provide additional sample status information.

Results: The Access Anti-HCV assay met stated claims for within-laboratory imprecision, demonstrating combined and within-site reproducibility below 0.100 S/CO SD for negative samples and below 10.0% CV for positive samples. A total of 360 samples were tested for potential cross-reactivity with 100.0% specificity obtained. Samples containing up to 1000 mg/dL hemoglobin, 15 g/dL total protein, 43 mg/dL bilirubin, 3510 ng/mL biotin, or 37 mmol/L intralipid showed no interference. Concordance analysis with the Abbott ARCHITECT Anti-HCV assay showed a negative percent agreement of 98.9% and a positive percent agreement of 98.7%. Six PCR-positive hospitalized patient samples that were detected by the Access Anti-HCV assay were not detected by the Abbott ARCHITECT Anti-HCV assay, suggesting potentially better sensitivity with these 6 samples compared with the Abbott ARCHITECT Anti-HCV assay.

Conclusion: The newly developed Access Anti-HCV assay for use on the DxI 9000 Access Immunoassay Analyzer demonstrated excellent analytical performance and strong agreement with currently marketed anti-HCV assays.

The study found:

• No interference with hemoglobin, protein, bilirubin, biotin or intralipid
• Excellent positive and negative percent agreement with potentially better sensitivity than currently marketed anti-HCV assays
• High analytical specificity and reproducibility

To Read the Poster: Click here  

References:

1. World Health Organization. Hepatitis C. Hepatitis C. June 24, 2022. Accessed July 5, 2023. https://www.who.int/news-room/fact-sheets/detail/hepatitis-c

2. Stockman LJ, Guilfoye SM, Benoit AL, Vergeront JM, Davis JP, Centers for Disease Control and Prevention (CDC). Rapid hepatitis C testing among persons at increased risk for infection--Wisconsin, 2012-2013. MMWR Morb Mortal Wkly Rep. 2014;63(14):309-311.

*Full Name: DxI 9000 Access Immunoassay Analyzer