The aims of the study were: (i) to evaluate the prevalence of hepatitis C virus (HCV) antibodies (third generation tests) and RNA (standardized ultrasensitive RT-PCR assay) in a large cohort of hemodialysis patients, and (ii) to correlate HCV markers with bioclinical features and alanine-aminotransferase (ALT) activity. Antibodies were assayed by two methods in 1,323 patients (60% men, median age 65 years, median hemodialysis duration 3 years) attending 25 French hemodialysis centers including 9 self-care units. RNA was assayed using the Cobas Amplicor 2.0 method in pooled samples from 10 anti-HCV(-/-) patients and on individual samples from the other patients. Of the 16.3% patients (range 0-44%) tested (+/+) for HCV antibodies (anti-HCV), 2.3% tested (+/-) and 81.4% tested (-/-). 70% of the anti-HCV(+/+) patients and 3% of the HCV(+/-) patients were RNA(+). Pooled analysis revealed that 5/1077 anti-HCV(-/-) patients (0.5%) were RNA(+); all 5 displayed subsequently an increase in ALT and became anti-HCV(+/+). Mean ALT was higher (multiple of normal) in anti-HCV(+/+) RNA(+) patients than in anti-HCV(+/+) RNA(-) patients (0.46 +/- 0.08 vs. 0.22 +/- 0.07, P < 0.0001) and similar in all the RNA(-) patients, whatever their HCV antibody status. Multivariate analysis demonstrated that HCV status was linked to hemodialysis duration, previous kidney transplantation and positive anti-HBc. To summarize, the determination of the RNA status of anti-HCV(+/-) patients may have clinical relevance if a policy of isolation is contemplated. Standardized ultrasensitive RT-PCR assay combined with a pooling strategy is a promising method for use in epidemiological studies.
Copyright 2000 Wiley-Liss, Inc.