DIAGNOSIS OF HEPATITIS-C VIRUS-ASSOCIATED CHRONIC LIVER-DISEASE IN INDIA - COMPARISON OF HCV ANTIBODY-ASSAY WITH A POLYMERASE CHAIN-REACTION FOR THE 5' NONCODING REGION

The relative value of an anti-hepatitis C virus (HCV) serological assa y and reverse transcriptase-nested polymerase chain reaction assays (R T-PCR) were investigated for the constant 5' putative noncoding region of HCV for the diagnosis of HCV-associated chronic liver diseases in India. One hundred fifteen patients with biopsy proven chronic active hepatitis and 140 cases of cirrhosis of the liver were investigated fo r anti-HCV antibody using a second generation commercial enzyme-linked immunosorbent assay (ELISA). A proportion of these patients: 42 with chronic hepatitis and 27 with cirrhosis of the liver were analysed fur ther for HCV RNA in the serum using RT-nested PCR assay. Thirty-three (12.9%) of the 255 patients were positive for anti-HCV antibody and 23 of 69 (33.3%) patients were positive for HCV RNA in serum. Fifteen of the 33 (45.5%) anti-HCV positive patients had HCV RNA in the serum. E ight of 36 (22.2%) HCV seronegative patients tested were found with HC V RNA. This indicates that the diagnosis of HCV infection is not possi ble if it is based solely on the available serodiagnostic tests. Inclu sion of both assays improved the diagnostic efficiency, 18.8% (13/69) were negative for all virological markers associated with HBV and HCV infection. Since a majority of the chronic liver disease patients (143 /255 [56%]) were seronegative for either HBV or HCV infection, it is s ignificant that HCV RNA was detected in 38% (8/21) of a randomly selec ted group from these patients. The antibody assay and PCR were compare d using interclass correlation (kappa statistics). Both these tests we re found to be independent of each other. Considering the wide strain variation throughout the world, it is suggested that the current comme rcial anti-HCV testing is inadequate for the diagnosis of all HCV infe ctions in all geographical regions. (C) 1994 Wiley-Liss, Inc.