Hepatitis G virus infection in chronic dialysis patients and kidney transplant recipients

Background: The cloning of the hepatitis G virus(HGV), a novel RNA virus of the Flaviviridae family,has been very recently developed. HGV is known to be parenterallytransmitted and has been detected in several patients with cryptogenichepatitis. However, little information exists about the epidemiology of HGVinfection in renal patients. We studied 178 chronic dialysis patients and11 renal transplant individuals to evaluate prevalence risk factors andclinical manifestations of HGV infection in this population.Method: Hepatitis G virus infection has been detectedby a modified PCR technology which incorporates digoxigenin-labellednucleotides into the amplicon. Primers from the non-coding region and theNS-5 region of HGV are utilized for a single round amplification. Using astreptavidin surface and a biotin-labelled capture probe the labellednucleic acid is bound through the capture probe to the surface, and theamplified nucleic acid is detected using antibody to digoxigenin.Results: HGV RNA was detected in 6% of chronichaemodialysis (HD) patients (11/172), 36% of renal transplant recipients(4/11), and 17% (1/6) of patients on peritoneal dialysis treatment (CAPD).There were no significant differences between HGV positive and negativepatients on chronic HD treatment with regard to several demographic,biochemical and virological features. However, the frequency of anti-HCVantibody was significantly higher in HGV-positive than HGV-negativepatients (9/11 (82%) vs 51/161 (32%), P=0.006). In thewhole group of HGV RNA-positive patients, 78% (11/14) had a history ofblood transfusion requirements, 14/16 (87%) had co-infection with HCV, and1 (6%) had co-infection with HBsAg. There was no significant associationbetween HCV genotypes and HGV RNA positivity. Six (27.5%) of 16 HGVRNA-positive patients showed raised aminotransferase values in serum.Conclusion: Patients on maintenance dialysis andkidney transplant recipients are at increased risk of HGV infection; HGV isvery frequently associated to hepatitis C co-infection, regardless of HCVgenotype. HGV may be transmitted by blood transfusions but transmissionroutes other than transfusion are possible; 37.5% of HGV RNA-positivepatients showed raised serum amoinotransferase levels. Furtherinvestigations are necessary to clarify the role of HGV infection in thedevelopment of liver disease in this clinical setting.