SIMPLE FLUORESCENT ENZYME-IMMUNOASSAY FOR DETECTION AND QUANTIFICATION OF HEPATITIS-C VIREMIA

Background/Aims: The viral load of hepatitis C virus, as reflected by hepatitis C virus viremia, has been shown to have important clinical i mplications. In this study the hepatitis C virus core protein level in serum was evaluated for the detection and quantification of hepatitis C virus viremia. Methods: Hepatitis C virus core protein in serum was detected using a simple and sensitive fluorescent enzyme immunoassay. Hepatitis C virus core protein was quantitated in 100 healthy subject s, 258 patients with hepatitis C virus infection and 108 patients with non-hepatitis-C-virus-related chronic liver diseases, HCV-RNA was det ermined using the branched DNA (bDNA) assay and reverse-transcription polymerase chain reaction. Results: The detection limit of this fluore scent enzyme immunoassay was found between 10(4)-10(5) copies/ml HCV-R NA equivalent. There was a good correlation between the core protein a nd bDNA assay results (p<0.01). Hepatitis C virus core protein was det ected in 81% of patients with hepatitis C virus infection (acute hepat itis 4/5, chronic hepatitis 85/104, cirrhosis 64/73 and hepatocellular carcinoma 56/76) but in none of the healthy subjects and patients wit h non-hepatitis C virus chronic liver diseases. The amount of hepatiti s C virus core protein in patients with hepatitis-C-virus-related hepa tocellular carcinoma was lower compared to chronic hepatitis and cirrh osis (p<0.05). All 26 patients treated with interferon-alpha showed pa rallel changes between HCV-RNA and core protein levels. Conclusions: T his fluorescent enzyme immunoassay is simple and quick (assay time<3 h ) with sensitivity at least matching the bDNA assay Similar levels of hepatitis C virus core protein were detected in patients with chronic hepatitis and cirrhosis, but patients with hepatocellular carcinoma te nded to have a lo,Per level of hepatitis C virus core protein.