1. ¹Institute of Medical Microbiology and Hygiene, University of Regensburg, Regensburg, Germany
2. ²Department of Internal Medicine I, University of Regensburg, Regensburg, Germany

Correspondence: Dr A Knöll, Institute of Medical Microbiology and Hygiene, University of Regensburg, D-93042 Regensburg, Germany. E-mail: antje.knoell@klinik.uni-regensburg.de

Received 4 September 2003; Accepted 20 November 2003; Published online 8 March 2004.

Abstract

Hepatitis B virus (HBV) reactivation after allogeneic haematopoietic stem cell transplantation (allo-HSCT) is well known in HBsAg-positive carriers but has only occasionally been reported in patients with resolved HBV infection. We investigated six allo-HSCT recipients with pretransplant anti-HBs and anti-HBc antibodies for serologic markers of HBV infection and for the presence of HBV-DNA in serum. Reverse seroconversion, that is, reappearance of HBsAg after a gradual loss of anti-HBs, but no severe liver damage was observed in three patients at 14, 22 and 12 months after HSCT, respectively. There was an increase in HBV-DNA concentration prior to reverse seroconversion. One patient was repeatedly HBV-DNA positive (10²–10³ copies/ml) without reverse seroconversion. Sequencing of the HBsAg and precore region derived from the four HBV-DNA-positive patients showed no relevant mutations. In conclusion, this study demonstrated a high risk (50%) of reverse seroconversion in allo-HSCT recipients with resolved HBV infection. A highly sensitive HBV-DNA assay (TaqMan-PCR) allowed early identification of the individual patients at risk.