GB VIRUS-C INFECTION IN PATIENTS WITH CHRONIC HEPATITIS-B AND HEPATITIS-C BEFORE AND AFTER LIVER-TRANSPLANTATION

Recently, a novel virus, tentatively designated GB virus C (GBV-C) was identified in patients with hepatitis, The frequency of this novel vi rus infection was therefore investigated in 58 patients with chronic h epatitis B virus (HBV) infection and in 74 patients with chronic hepat itis C virus (HCV) infection who had received orthotopic liver transpl antation (OLT) because of decompensated liver cirrhosis, Before OLT, G BV-C sequences were found by reverse transcription nested polymerase c hain reaction with primers derived from the helicase-like region in si x (10%) of the HBV- and in six (8%) of the HCV-infected patients, Spec ificity of the polymerase chain reaction products was confirmed in eig ht of them by direct sequencing, Pretransplant GBV-C viremia was assoc iated with posttransplant viremia in 75% of patients. The comparison o f GBV-C nucleotide and amino acid sequences within the helicase-like r egion revealed that pre- and posttransplant sequences differed only in 0-7 nucleotide exchanges, and with the exception of one, all of them were silent mutations, After OLT, 29% of the HBV-infected and 12% of t he HCV-infected patients became GBV-C positive, indicating a high rate of ''de novo'' GBV-C infection, By correlating the GBV-C status with the frequency of the occurrence of graft hepatitis in both groups of p atients, it became evident that posttransplant GBV-C viremia did not i ncrease the risk for this clinical condition, However, we found a sign ificantly higher percentage of hepatocellular carcinoma in patients wi th pre-OLT GBV-C/HCV coinfection compared with patients with HCV infec tion alone (5/6 vs, 16/68; P < 0.01).