Incidence, transmission, and clinical significance of hepatitis G virus infection in hemodialysis patients

A high prevalence of hepatitis G virus (HGV) infection has been noted in pa tients receiving chronic hemodialysis (HD) therapy, yet the incidence rate and transmission route have rarely been reported. Serum samples from 160 ch ronically uremic patients in a HD unit were initially collected at the time chronic HD therapy was begun, and thereafter annually in July and, finally , in November 1999. Serum HGV RNA was detected using nested reverse transcr iption polymerase chain reaction, and HGV E2 antibody was determined using an enzyme immunoassay, Nucleotide sequences of the S'-noncoding region were studied in the HD patients with HGV viremia. Forty healthy staff members w ere also enrolled as control subjects. Three of the 40 (7.5%) healthy staff members were positive for HGV RNA or HGV E2 antibodies, in contrast to 40 of the 160 (25%) HD patients, including 14 (8.8%) who were positive for HGV RNA only, 25 (15.6%) who were positive for HGV E2 antibody only, and 1 (0. 6%) who had both markers. HGV exposure did not correlate with gender, age, duration of I-ID therapy, or history of blood transfusions. At least 20 of the 40 (50%) patients with HGV exposure had been infected before the start of chronic I-ID therapy. Nevertheless, at least nine (22.5%) patients acqui red new HCV infections after starting chronic HD therapy, with an incidence rate of greater than or equal to2.6% per year. Three patients with newly a cquired HGV viremia after HD therapy was started and two with pre-existing HGV viremia before HD therapy was started had the same nucleotide sequences . HGV and HCV infections (with a prevalence of 14.4%) might have been trans mitted independently in HD patients. In addition, HGV infection was not fou nd to cause significant elevation of alanine aminotransferase levels in the group exposed to HGV. To conclude, the incidence of new HGV infections was at least 2.6% per year. In addition to transmission through blood transfus ion, HGV may have been transmitted nosocomially patient-to-patient within t he HD unit. The compliance with standard universal precautions should be ca refully re-examined, but it is not necessary to routinely screen for HGV in fection among patients on chronic HD.