Long-term impact of co-infection by hepatitis G virus in hepatitis C viruspositive renal transplant patients

The objectives of this retrospective study were to determine the prevalence of hepatitis G virus (HGV) infection in hepatitis C virus positive (HCV+ve ) renal transplant (RT) patients and to evaluate the impact of HGV both on liver function tests, liver histology tests and renal parameters such as th e prevalence of acute rejection and renal function. Seventy-one HCV+ve renal transplant patients with a functioning graft for w hom a post renal transplant liver biopsy was available, were included. Seru m HGV RNA was assessed by reverse transcription polymerase chain reaction b efore, at the time of, and after renal transplantation. A total of 21 (30%) of the HCV+ve RT patients had a positive HGV RNA (Group 1); seventeen of these patients (81%) were already HGV RNA+ve when the mos t recent renal transplantation was performed. The other 4 patients became H GV RNA+ve following renal transplantation. The mean duration of HGV infecti on was at least 119 +/- 64 months (18-240). Patients in group 1 did not sta tistically differ from the 50 HGV RNA-ve/ HCV+ve RT patients (Group 2) acco rding to sex ratio; time on dialysis; number of blood transfusions; HLA mat ching; the duration of HCV infection; duration and type of immunosuppressio n or levels of liver enzymes i.e. aspartate aminotransferase, alanine amino transferase and gamma glutamyl transpeptidase; serum HCV RNA concentration; or frequency of genotype 1b. However, Group 1 patients were statistically younger (41 +/- 10 y compared to 47 +/- 10 y; p = 0.016) than Group 2 patie nts. Liver histology showed a significantly lower degree of fibrosis in Gro up 1 (0.4 +/- 0.5) than in Group 2 (1 +/- 1.2, p = 0.02); two patients from Group 2 but none of Group 1 had overt cirrhosis. Conversely, the extent of hepatic inflammation and hepatocellular necrosis was not statistically dif ferent between the two groups. The number of patients who experienced at le ast one acute rejection episode was significantly higher in Group 1 (76.2%) than in Group 2 (46%; p = 0.02), although the difference was no longer sig nificant in the multivariate analysis. In conclusion, this study shows that: i) HGV infection was often present wh en the patients seroconverted for HCV; ii) HGV RNA+ve/HCV+ve RT patients ex perience acute rejection more frequently than HGV RNA-ve/HCV+ve RT patients ; iii) HGV infection seems to have no detrimental effect upon liver enzymes or liver histology in HCV+ve RT patients.