Hepatitis G virus (HGV) is a recently described hepatotropic parenterally transmitted flavivirus. The presence of HGV was tested in 61 patients with a request for confirmation of HCV active infection. Thirty-two patients were in haemodialysis and 29 were referred from wards other than nephrology. Active HCV and HGV infections were determined by detection of their viral RNA in serum. Evaluation of previous HGV infection was carried out by detection of antibodies to E2 antigen. HCV prevalence was 62.29% (38/61). HGV-active infection was found in 11.47% (7/61) of the population studied: in 18.7% (6/32) of the haemodialysed patients and in 3.4% (1/29) of patients belonging to the other group. HGV prevalence increased two-fold when previous infection was also considered. HGV clearance was prospectively detected in 5 out of the 7 patients with active infection, and at an earlier stage for those patients coinfected with HCV. Anti-E2 seropositivity was associated with HGV clearance in only two patients.