Usefulness of the Hepatitis C Virus Core Antigen Assay for Screening ...

1 downloads 0 Views 58KB Size Report
Sep 13, 2004 - Unité Virus et Pseudovirus: Morphogéne`se et Antigénicité LEA3865, Université François Rabelais, Tours,1 and Institut inter Régional pour la ...
JOURNAL OF CLINICAL MICROBIOLOGY, Apr. 2005, p. 1722–1726 0095-1137/05/$08.00⫹0 doi:10.1128/JCM.43.4.1722–1726.2005 Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Vol. 43, No. 4

Usefulness of the Hepatitis C Virus Core Antigen Assay for Screening of a Population Undergoing Routine Medical Checkup Catherine Gaudy,1 Catherine Thevenas,2 Jean Tichet,2 Nicole Mariotte,2 Alain Goudeau,1 and Fre´de´ric Dubois1,2* Unite´ Virus et Pseudovirus: Morphoge´ne`se et Antige´nicite´ LEA3865, Universite´ Franc¸ois Rabelais, Tours,1 and Institut inter Re´gional pour la Sante´, La Riche,2 France Received 13 September 2004/Returned for modification 27 October 2004/Accepted 15 December 2004

We studied the usefulness of the recently designed Trak-C assay for the detection and quantification of the hepatitis C virus (HCV) core antigen (Ag) for the screening of HCV infection in 4,201 subjects selected from 74,150 consecutive volunteers undergoing routine medical checkups. Subjects were selected for screening because they had risk factors (group II, n ⴝ 321) and/or elevated alanine transaminase activity (group I, n ⴝ 3847). Initially, the anti-HCV antibody assay and the Trak-C assay were performed on each patient. Subsequently, the Trak-C assay was performed only when the anti-HCV enzyme immune assay (EIA) was positive. Positive samples were further evaluated for anti-HCV antibodies by a third-generation strip immunoblot assay and for HCV RNA. Four samples (1.2%) from group II and 113 (2.9%) from group I were anti-HCV EIA positive. We also tested 33 subjects who previously tested positive for anti-HCV in our medical center. Among the 150 anti-HCV EIA-positive samples, the HCV core Ag result was in accord with the HCV RNA result in 146 cases (97.3%). When the EIA result was positive, the HCV core Ag concentration and the HCV RNA load were correlated (r 2 ⴝ 0.78; P < 0.001). Four samples with low viral loads were Trak-C negative but HCV RNA positive. Among the 2,395 anti-HCV EIA-negative serum samples collected during the first part of the study, 17 (0.7%) were found to contain very low levels of HCV core Ag (