Determination of anti-HCV signal to cut-off value in patients with hepatitis C virus infection and the variety of antibody responses

Authors : Murat OCAL, Mehmet Emin BULUT

Pages : 484-494

Doi:10.18621/eurj.945588

View : 17 | Download : 16

Publication Date : 2023-05-04

Article Type : Research Paper

Abstract :Objectives: The diagnosis of hepatitis C virus insert ignore into journalissuearticles values(HCV); infection starts with the detection of antibodies against recombinant or synthetic HCV proteins by Enzyme Immunoassay insert ignore into journalissuearticles values(EIA);. Although EIA tests are highly sensitive, false positivity rates are not low. Positive anti-HCV results are generally confirmed with complementary tests such as Nucleic Acid Amplification Tests insert ignore into journalissuearticles values(NAAT);, or Western Blot modifications. Methods: The anti-HCV results of 199,516 individuals referred from various clinics between 2015 and 2019 were evaluated retrospectively at University of Health Sciences, Şişli Hamidiye Etfal Training and Research Hospital, Medical Microbiology Laboratory. From the 2039 samples, of which EIA tests resulted borderline and reactive, 1419 samples having Line Immunoassay insert ignore into journalissuearticles values(LIA); confirmatory test results were included in the study. Results: LIA tests yielded positive, negative and indeterminate for 820 insert ignore into journalissuearticles values(57.8%);, 519 insert ignore into journalissuearticles values(36.6%); and 80 insert ignore into journalissuearticles values(5.6%); of 1419 samples, respectively. The optimal threshold point for EIA anti-HCV signal to cut-off insert ignore into journalissuearticles values(S/Co); according to LIA was found to be 15.85 corresponded to diagnostic sensitivity, specificity, positive predictive value insert ignore into journalissuearticles values(PPV);, negative predictive value insert ignore into journalissuearticles values(NPV); and accuracy of 94.9%, 94.8%, 96.6%, 92.1%, 94.9%, respectively. The most common proteins detected in LIA positive samples were C1 96.3%, C2 90.4%, and NS3 93.2%. Conclusions: To prevent false positivities, confirmatory tests must be used for samples with low S/Co ratios. The use of S/Co value will make significant contribution to reducing both false-positive results and the LIA confirmatory test consumption. There was no correlation between the number of bands and EIA index values in LIA positive samples, while the relationship between the number of 3+ bands and index values was remarkable.
Keywords : Hepatitis C virus, signal to cut off, enzyme immunoassay, line immunoassay, confirmatory test