Evaluation of a new enzyme immunoassay for hepatitis C virus (HCV) core antigen with clinical sensitivity approximating that of genomic amplification of HCV RNA

• Published in: Hepatology (Baltimore, Md.) Vol. 32; no. 2; pp. 388 - 393
• Main Authors: Tanaka, Eiji, Ohue, Chiharu, Aoyagi, Katsumi, Yamaguchi, Kenjiro, Yagi, Shintaro, Kiyosawa, Kendo, Alter, Harvey J.
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Elsevier Inc 01-08-2000; W.B. Saunders; Wiley
• Subjects: Acute Disease; Adult; Aged; Biological and medical sciences; Digestive system; Female; Hepacivirus - immunology; Hepatitis C Antigens - blood; Hepatitis C, Chronic - diagnosis; Hepatitis C, Chronic - drug therapy; Humans; Immunoenzyme Techniques; Interferon-alpha - therapeutic use; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Middle Aged; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Reverse Transcriptase Polymerase Chain Reaction; RNA, Viral - blood; Sensitivity and Specificity; Transfusion Reaction; Viral Core Proteins - blood; Infection; Antigen; Human; Viral disease; Nucleocapsid; Digestive diseases; Hepatic disease; Medical screening; Enzyme immunoassay; Comparative study; Viral hepatitis C
• ISSN: 0270-9139; 1527-3350
• DOI: 10.1053/jhep.2000.9112

The aim of this study was to analyze the clinical performance of a new enzyme immunoassay (EIA) for hepatitis C virus (HCV) core antigen in comparison with the reverse transcription polymerase chain reaction (RT-PCR). A total of 310 patients with acute or chronic hepatitis C, and 132 HCV-negative controls were studied. Chemiluminescence EIA with monoclonal anti-HCV core antigen was used, and qualitative and quantitative commercial RT-PCRs and an in-house nested RT-PCR were performed. Compared with nested RT-PCR, the core antigen assay showed 97% sensitivity and 100% specificity in 75 patients with chronic hepatitis C and 132 controls. HCV core antigen was positive in 16 (94%) of 17 patients with acute hepatitis C at initial consultation. In 3 persons prospectively followed, core antigen was detected in the first available (1-3 weeks) post-transfusion sample. In 167 anti-HCV–positive individuals, 129 (77%) were viremic; core antigen was detected in 126 (98%) compared with 129 (100%) for nested RT-PCR and 121 (94%) for the commercial RT-PCR. In 48 patients with chronic hepatitis C treated with interferon alfa, the concentration of core antigen before treatment was significantly (P < .002) lower in patients with sustained response than in nonresponders. All responders had a sustained loss of core antigen, whereas all nonresponders remained core antigen positive. The concentrations of HCV core antigen and HCV RNA correlated significantly (n = 48, r = .627, P < .001). In conclusion, the HCV core antigen assay is useful for the diagnosis of acute and chronic hepatitis C, and for predicting and monitoring the effect of interferon alfa treatment. (Hepatology 2000;32:388-393.)