Background . Reactivation of hepatitis B virus (HBV) infection following allogeneic bone marrow transplantation is a rare phenomenon.

Methods . Reverse seroconversion, defined as the clearance of antibody to hepatitis B surface antigen (HBsAb) and the appearance of hepatitis B surface antigen (HBsAg) in a patient with resolved HBV infection (i.e., a HBsAg-negative, HBsAb-positive, hepatitis B core antibody–positive patient) following receipt of a bone marrow transplant is described. A review of related cases in the literature was undertaken to identify clinical features associated with this phenomenon.

Results . We present a case of reactivation of HBV infection in a 47-year-old man after receipt of an allogeneic bone marrow transplant for acute myelogenous leukemia. Before undergoing bone marrow transplantation, the presence of HBsAb and hepatitis B core antibody and the absence of HBsAg indicated clearance of natural HBV infection. The donor was HBsAg and HBsAb negative. Twenty-nine months after bone marrow transplantation, the patient developed transaminitis and evidence of active HBV infection (the patient had test results positive for HBsAg, negative for HBsAb, and positive for HBV DNA). A total of 28 other cases of reverse seroconversion have been described in the literature, 11 of which provided adequate information to be summarized in detail together with the present case. Reactivation of HBV infection following bone marrow transplantation appears to occur almost exclusively in patients who have received marrow from an HBsAb-negative donor and have experienced graft-versus-host disease, the onset of which is associated with tapering of immunosuppressive therapy.

Conclusions . Although HBV reverse seroconversion is an uncommon event, understanding the clinical features associated with the development of HBV reverse seroconversion may provide insight into how such a potentially fatal complication may be avoided.