HEPATITIS-C VIRUS-INFECTION IN HEMODIALYSIS-PATIENTS - COMPARISON OF 2 NEW HEPATITIS-C ANTIBODY-ASSAYS WITH A 2ND-GENERATION ASSAY

The performance of two new hepatitis C virus antibody (anti-HCV) assay s (a third-generation immunoglobulin (Ig)G recombinant immunoblot assa y (RIBA 3.0) and hepatitis C virus core IgM (HCV IgM)) in the predicti on of hepatitis C viremia in hemodialysis patients was compared with t hat of a second-generation lgG recombinant immunoblot assay (RIBA 2.0) . Forty-three patients on maintenance hemodialysis were studied. Aliqu ots of sera were tested prospectively for anti-HCV by RIBA 2.0, RIBA 3 .0, and HCV IgM and for HCV RNA by polymerase chain reaction. Thirty-e ight patients were HCV RNA positive. Among those, 7 (18%) were HCV IgM positive, 22 (58%) were RIBA 2.0 positive, and 29 (76%) were RIBA 3.0 positive. All but one viremic patients detected by HCV IgM were also detected by RIBA 2.0 and RIBA 3.0. All viremic patients detected by RI BA 2.0 were also detected by RIBA 3.0. RIBA 3.0 was more sensitive tha n RIBA 2.0 and HCV IgM in the detection of viremic patients (P = 0.015 6 and < 0.0001, respectively). The positive predictive value for HCV I gM was 100% as compared with 96 and 97% for RIBA 2.0 and RIBA 3.0, res pectively. The negative predictive value for RIBA 3.0 was 36% as compa red with 24 and 14% for RIBA 2.0 and HCV IgM, respectively. At 6-month s follow-up of the eight viremic patients without a detectable IgM or IgG anti-HCV response, all patients remained RIBA 2.0 nonreactive, one became RIBA 3.0 indeterminate, and one became HCV IgM positive. These data suggest that HCV IgM has poor sensitivity in the detection of he patitis C viremia and RIBA 3.0 improves the sensitivity of IgG anti-HC V assays in the early detection of hepatitis C viremia in hemodialysis patients.