ANTIBODY-RESPONSES TO HEPATITIS-C VIRUS BY 2ND-GENERATION IMMUNOASSAYS IN A COHORT OF PATIENTS WITH BLEEDING DISORDERS

The antibody responses and the prevalence patterns of antibodies to hepatitis C virus (anti-HCV) in a cohort of patients (n = 210) with bleeding disorders were studied using a first-generation and a second-generation enzyme immunoassays (EIA-1, EIA-2) as well as a second-generation recombinant immunoblot assay (RIBA-2). The anti-HCV prevalence as determined by EIA-1 and EIA-2 was 183/210 (87.1%) and 197/210 (93.8%), respectively (p = 0.0026). None of the 17 EIA-2(+)/EIA-1(-) samples was scored nonreactive by RIBA-2. At follow-up, samples of 123 patients were tested. Twenty-nine out of 111 patients reactive by EIA-1 seroreverted according to EIA-1 while the seroreversion rate with EIA-2 was 0 out of the 121 (p < 10(-8)). The anti-HCV prevalence by EIA-2 was 150/154 (97.4%) in anti-HIV-1-positive individuals and 47/56 (83.9%) in the anti-HIV-1-negative ones (p = 0.001). However, high assay signals (OD 492 nm > 2.0) were observed in 94/150 (62.7%) and 45/47 (95.7%) of the anti-HIV-1-positive and -negative patients, respectively (p = 10(-5)). The decreasing anti-HCV reactivity among anti-HIV-1-positive individuals was mainly due to diminishing c33c reactivity. Seroconversion to anti-HCV was observed in 3/7 (42.9%) cases with acute icteric non-A, non-B hepatitis by both EIA-1 and EIA-2, while the remaining 4 cases had detectable levels of anti-HCV 1-18 months before the acute episode.