Hepatitis C virus genotypes and hepatitis G virus in hemodialysis patients from Syria: identification of two novel hepatitis C virus subtypes.

High prevalence of hepatitis C (HCV) and hepatitis G (HGV) viruses has been reported among hemodialysis patients with substantial heterogeneity of HCV genotypes throughout the world. We studied HCV prevalence, clinical significance, genotype distribution, and HGV coinfection in hemodialysis patients from Syria. Ninety (75%) of 120 screened patients were HCV antibody positive. Forty-nine (87.5%) of 56 HCV antibody-positive patients had HCV RNA detected by the polymerase chain reaction. The HCV genotyping was possible in 37 of 49 patients (76%). The HCV genotype distribution was genotype 1a, seven (19%); genotype 1b, 10 (27%); genotype 4a, 11 (30%); unmatched sequences, nine (24%). Phylogenetic analysis of unmatched sequences indicated that they represent two distinct and novel subtypes of HCV genotype 4. Hepatitis G virus RNA was detected in 29 (59%) of the HCV RNA-positive patients. No differences were identified between patients infected with HCV alone and those coinfected with HGV. These data demonstrate that HCV infection is common in this population with a genotype distribution predominantly made up of types 1 and 4. Coinfection with HGV had no effect on the outcome of HCV infection.