To determine the prevalence and clinical relevance of HGV infection in dialysis patients, we performed a cross-sectional study of 61 HD patients and 79 Continuous Ambulatory Peritoneal Dialysis (CAPD) patients. HGV-RNA was identified by reverse-transcription (RT) polymerase chain reaction (PCR) assay with primers from the 5'-untranslated region of the viral genome. The prevalence of HGV infection was similar in HD and CAPD patients (9.8% vs. 12.7%), while that of HCV infection was significantly higher in HD patients compared to CAPD patients (16.4% vs. 1.3%, p < 0.05). The mean age (49.2 +/- 13.4 vs. 46.7 +/- 13.0 years), male to female ratio (2.4:1 vs. 1.3:1), history of transfusion (62.3% vs. 49.4%), history of hepatitis (27.9% vs. 26.6%), mean ALT level during the previous 6 months (22.4 +/- 37.9 vs. 14.0 +/- 7.4 IU/L), and the prevalence of HBsAg (8.2% vs. 6.3%) showed no difference between HD and CAPD patients. In both HD and CAPD patients, the presence of HGV RNA was not related to age, sex, duration of dialysis, history of transfusion, history of hepatitis, or to the presence of HBV or HCV markers. There was no significant difference in the clinical and biochemical data between patients with isolated HGV infection (n = 12) and patients without viremia (n = 106). The clinical feature of patients coinfected with HGV and HBV (n = 2), or HGV and HCV (n = 2) seemed to be similar to those of patients with isolated HBV (n = 8) or HCV (n = 9) infection. In conclusion, the prevalence of HGV infection was not different between HD and CAPD patients, and HGV infections did not seem to be associated with clinically significant hepatitis. The routes of HGV transmission, other than transfusion or contamination during HD procedure, were suspected.