Significance of the hepatitis C virus core antigen testing as an alternative marker for hepatitis diagnosis in Egyptian patients

OBJECTIVE: Hepatitis C virus (HCV) core antigen (Ag) quantification by enzyme- immunoassays has been proposed as an economic and simpler alternative to HCV RNA detection. The current study was undertaken to assess the significance of HCV core antigen assay for the diagnosis of chronic HCV infection and monitoring response to antiviral therapy in Egyptian patients. PATIENTS AND METHODS: Sixty three HCV antibody positive patients and ten interferon-treated patients were included in the current study. The included patients were divided according to their viral load into four groups as follows; group I (n= 10): HCV RNA loads <= 10000 IU/ml, group II (n= 20): HCV RNA loads > 10000 <= 100000 IU/ml, group III (n= 33): HCV RNA loads > 100000 IU/ml and group IV (n=10): interferon-treated HCV patients with a negative HCV RNA. Serum HCV core Ag and RNA loads were assayed and their correlations, including linear regression lines, were calculated. RESULTS: HCV core Ag exhibited a non-significant (p > 0.05) difference between all the studied groups. Concerning, group I patients, HCV core Ag levels and HCV RNA loads were positively correlated, with a correlation coefficient of 0.73 (p < 0.05). Group II and III showed stronger correlations; the recorded values were 0.81 (p < 0.0001) and 0.94 (p < 0.0001) for group II and III, respectively. CONCLUSIONS: HCV core Ag test can be used as an alternative to HCV RNA tests to evaluate chronic infection when the HCV RNA test is unavailable, but is not reliable enough for treatment monitoring.