Correlation between architect hepatitis C virus (HCV) core antigen and HCV Ribonucleic acid levels in Anti-HCV reactive patients in Turkey

Quantitative tests for the detection of hepatitis C virus ribonucleic acid (HCV-RNA) levels and HCV core antigen have been mainly used for the management of patients with HCV infection. The aim of this study was to evaluate the correlation between HCV core antigen and HCV RNA levels in patients reactive for anti-HCV antibodies. Three hundred and twenty-five anti-HCV reactive sera samples were included in the study. HCV core antigen and HCV RNA levels were determined using the Architect HCV Ag test and Abbott RealTimeTM HCV RNA test (RT-PCR), respectively. The correlation coefficient between the levels of HCV core antigen and HCV RNA test results was calculated using Spearman’s rank test, and linear regression analysis was applied. One hundred and sixteen of the 325 samples were detected positive by both methods. Three additional samples by RT-PCR, and 4 samples by Architect HCV Ag, the negative samples were found positive by the other method. All of these contradictory results were obtained from the low level HCV RNA or HCV core antigen including samples. A correlation coefficient (r) was determined as 0.899 between the levels of HCV core antigen and HCV RNA (p<0.0001). The sensitivity, specificity, positive predictive value and negative predictive value of the HCV core antigen test were 97.48, 98.06, 96.67 and 98.54%, respectively, using the HCV RNA test as a reference. The Architect HCV core antigen test exhibits a good correlation with the HCV RNA test. It can be used as an alternative method, especially when the HCV RNA test is unavailable.   Key words: Anti- hepatitis C virus, Architect hepatitis C virus Ag test, hepatitis C virus RNA.