Hepatitis C virus infection in an HIV-positive population in Normandy: antibodies, HCV RNA and genotype prevalence.

The prevalence and the characteristics of hepatitis C virus infection (HCV) in 161 HIV-positive patients were studied. HCV seroprevalence was determined by enzyme immunoassay and recombinant immunoblot assay (RIBA). Two different reverse transcriptase polymerase chain reaction (RT-PCR) methods were also used to test the HCV-seropositive samples and 50 EIA-negative sera used as controls. The RNA HCV-positive sera were genotyped by the LiPA procedure. Associations of HCV status with demographic characteristics and risk factors were assessed by chi 2 and Fisher's exact tests. The seroprevalence of HCV was 34.2% with a significant difference between blood and sexual exposure risk groups (60.6% vs. 13.6%, respectively; P < 0.0001). Thirty-six of the 55 anti-HCV-positive sera were also positive for HCV RNA, and PCR detected HCV RNA in 8 HCV-seronegative patients. Various RIBA profiles were found and all sera were positive for antibodies to the c33 protein. A proportion of sera had elevated levels of transaminase activity (37.2%), and abnormal liver function as associated with HCV infection. Forty-two samples were genotyped and five genotypes and subtypes of the HCV virus were detected. Genotype 1a was the most frequent in this cohort, although genotype 1b is generally more common in France. The majority (94.1%) of the patients with genotype 1a had a history of blood exposure, which may account for the difference.