Spontaneous resolution of de novo hepatitis B after living donor liver transplantation with hepatitis B core antibody positive graft: a case report

BACKGROUND Hepatitis B core antibody (HBcAb)-positive graft is reported to cause de novo hepatitis B after liver transplantation with a probability of 38-100 % without prophylaxis. Hepatitis B surface antigen loss is reported to be achieved with a probability of only 3-8 % in the patients treated by antiviral agents. We present an extremely rare case of spontaneous resolution of de novo hepatitis B after living donor liver transplantation (LDLT) with HBcAb-positive graft. CASE PRESENTATION An 8-year-old female patient underwent LDLT for end-stage biliary atresia using an HBcAb-positive left lobe graft. After transplantation, she did not receive any prophylactic agents for hepatitis B. Two years after LDLT, she was diagnosed with chronic hepatitis B. Six years after LDLT, liver fibrosis and hepatitis activity were advanced and lamivudine was started. Two years after lamivudine administration, emergence of a lamivudine-resistant YMDD mutant was detected and adefovir dipivoxil was combined with lamivudine. Hepatitis B virus deoxyribonucleic acid (HBV-DNA) became undetectable soon after the addition of adefovir dipivoxil. Twelve years after transplantation, acute rejection occurred and steroid pulse therapy was performed, but hepatitis B did not become severe and HBV-DNA continued to be undetectable. Fifteen years after LDLT, she voluntarily discontinued medication of all drugs, including immunosuppressive agents and antiviral drugs for 1 year because of mental instability. After an interval of 1 year, liver function was normal and her serological HBV status was as follows: HBsAg(-), HBsAb(+), HBeAb(-), HBeAb(+), HBcAb(+) and HBV-DNA(-). From these results, we diagnosed her condition as spontaneous clearance of de novo hepatitis B. The patient is free of antiviral therapies and continues to take a low dose of immunosuppressive drugs and is leading a normal life. CONCLUSIONS In this case, HBsAg loss is finally achieved but we need to follow carefully for HBV reactivation with the fibrosis of the graft in mind.