evolution of wildtype and precore mutant hbv infection after liver transplantation recurrence of hepatitis b virus hbv infection after liver transplantation is associated with varying degree of graft damage the aim of the study was to investigate longitudinally the changes of wildtype and precore a1896hbv mutant viral populations after reinfection and their impact on liver graft damage the wildtype hbv and a1896hbv strains were quantitated before and serially after orthotopic liver transplantation olt in 14 hepatitis b surface antigen hbsagpositive liver graft recipients 4 hepatitis b e antigen hbeag 10 antihbe before olt the wildtype precore hbv was present in all 4 hbeagpositive patients and in 210 antihbepositive patients a mixed virus population was present in 6 patients and a1896hbv mutant alone in 2 patients after olt a1896hbv mutant appeared and gradually accumulated in 56 patients who had the wildtype hbv before olt and 1 of these patients seroconverted from hbeag to antihbe 52 months after transplantation a mixed hbv population was present continuously in 6 patients before and after olt of the 2 patients with a1896hbv only preolt the wild type appeared in one patient and the other patient retained persistently the a1896hbv mutant there was no relationship between liver graft histology and the type of viral population at reinfection or at the end of follow up changes in the hbv population occur during follow up of recurrent hepatitis b in liver transplant recipients with frequent accumulation of precore a1896hbv mutants but the type of viral population does not determine the severity of hepatitis b in the graft