Rapid immunoassay alone is insufficient for the detection of hepatitis C virus infection among high-risk population

Rapid testing for HCV has become a routine practice in resource-limited settings for initial screening. The objective of this study was to evaluate the performance of rapid immunoassay diagnostic test kits for specific and accurate diagnosis of HCV infection among different patient groups in clinical settings of Kolkata, India. Two hundred and fifty-four randomly selected serum samples of 612 samples reported as HCV nonreactive by rapid immunodiagnostic tests were evaluated for HCV antibody, ELISA and HCV RNA testing for confirmatory diagnosis. 15.74% were HCV seropositive by ELISA, and 11.02% were RNA positive by nested RT-PCR. Additionally, 15 HCV-seronegative chronic liver disease patients with high ALT and AST values were screened for HCV RNA, of which five were positive whose viral load ranged from 1.2x102 to 4.4x106IU/mL, and the samples belonged to IVDUs and HIV-co-infected individuals. The results showed that HCV rapid immunoassay test cannot be solely relied on as an absolute and accurate diagnostic tool for screening infection of HCV particularly in high-risk group patients such as IVDUs, haemodialysis, thalassaemic and HIV-co-infected patients who need HCV screening frequently.