Hepatitis C virus genotype in anti-HCV-positive hemodialysed patients

We investigated the influence of hepatitis C virus (HCV) genotypes on the clinical course of HCV infection in a haemodialysis population. In June 1991, a 4 year prospective follow-up programme was implemented in 184 consecutive haemodialysis patients. Alanine aminotransferase (ALT) and gamma glutamine transferase (GGT) were performed every 2 months. When HCV antibody (Ab) (by second-generation ELISA) was positive, it was confirmed by RIBA 2 and HCV RNA amplification by PCR. The pattern of nucleotide sequence variability in the 5' non-coding region was categorized according to Simmonds' genotype classification. Risk factors including blood transfusions were evaluated. The levels of hepatic enzymes in HCV Ab-positive patients were retrospectively studied over a mean period of 11.8 years. ALT and GGT levels were assigned a score for every year of infection (0 = normal, 1 = fluctuating 2 = high levels). Fifty-two patients were HCV Ab reactive (30.4%), eight were RIBA undetermined and 44 were RIBA positive; 40 of these were HCV RNA positive (91%). Twelve patients were HCV RNA negative, suggesting that they had recovered from the infection. Four genotypes were identified: 1b [26 patients (65%)], 1a (one patient), 2 [12 patients (30%)] and 3 (one patient). The genotype distribution was not different from that found in patients with chronic hepatitis C and normal renal function of the same geographical area. Genotype 1b accounted for 75% of the cases before 1985 and an equal prevalence of the two major genotypes was observed after 1985. Patients infected with HCV subtype 1 had normal mean ALT levels, but higher levels in the follow-up period (28 +/- 15.6 IU/l) and higher ALT and GGT personal scores in the retrospective study. Genotype 1 patients had higher mean ALT levels after 6 months. HCV RNA-negative patients had lower ALT levels after 24 months. RIBA pattern could differentiate the patients. Patients with genotype 1 received a higher number of transfusions, while only 50% of HCV RNA-negative patients had been transfused. Our data suggest a worse course of HCV infection in haemodialysis patients infected with HCV subtype 1, but the severity of HCV infection can only be assessed by histology. Transaminases are only loosely correlated with severity.