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Reverse seroconversion of hepatitis B after allogeneic bone marrow transplantation: a retrospective study of 37 patients with pretransplant anti-HBs and anti-HBc.

BACKGROUND
Reverse seroconversion to hepatitis B virus (HBV), i.e., HBV reactivation in patients with pretransplant antibodies to hepatitis B surface antigen (anti-HBs) and to hepatitis B core antigen (anti-HBc), is rarely re-ported after allogeneic bone marrow transplantation.


METHODS
To determine this risk, we studied clinical outcome and serological changes in 37 patients with pretransplant anti-HBs and anti-HBc.


RESULTS
In 33 cases, no change in HBV markers was observed in the posttransplant period. In four cases, anti-HBs and anti-HBc were lost, and hepatitis B surface antigen, hepatitis B e antigen, and HBV DNA emerged together with acute hepatitis, after cessation of immunosuppression. The actuarial risk of reactivation in the 37 patients was 20.5% (median follow-up 20 months). No reactivation occurred in patients with anti-HBs-positive donors.


CONCLUSION
Although few cases of postallogeneic bone marrow transplantation reverse seroconversion to HBV have been reported, this study demonstrates that the actuarial risk is relatively high and suggests that donor vaccination might be proposed prophylactically or that HBs-specific immunoglobulin infusions might be warranted.