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Detection of hepatitis b virus DNA in the blood of a stem cell donor after granulocyte colony‐stimulating factor treatment

Occult hepatitis B virus (HBV) infections have gained much attention in terms of transmissibility and reactivation. Here, we report the case of a healthy stem cell donor with serological evidence of a resolved HBV infection who became temporarily HBV DNA–positive in the blood after stimulation with granulocyte colony-stimulating factor (G-CSF). A 51-year-old man from the German Bone Marrow Donor Center was identified as human leukocyte antigen matching (10/10) stem cell donor for a 44-year-old female patient diagnosed with precursor B-cell acute lymphoblastic leukemia in the United Kingdom. This donor was a well-known blood donor since 2009 and was previously tested positive for antibody to hepatitis B core antigen, antibody to hepatitis B e antigen, and antibody to hepatitis B surface antigen (anti-HBs). During the diagnostic workup the serological findings could be confirmed and HBV DNA was not detected. Thus, in accordance with German regulations, this donor was considered eligible for stem cell donation. The donor started G-CSF treatment, and at day 5 cluster of differentiation 34 (CD34)–positive stem and progenitor cells were collected. At this time HBV DNA (pooled tested, detection limit 257 IU/mL) tested negative. The product was shipped from the German apheresis center to the UK transplantation center and infused after myeloablative conditioning of the patient had been completed. Six days after transplantation, testing of the product at the transplantation center revealed the presence of 26 IU/mL HBV DNA, which could be confirmed by testing backup samples (product and blood) (Table 1; Supporting Information). Therefore, the stem cell recipient immediately started lamivudine treatment and has tested negative for HBV DNA (last test day 1130) ever since. AntiHBs of the recipient was negative before transplantation but temporarily positive after transplantation (Supporting Information). HBV DNA testing of the donor was again negative at day 16 after apheresis. Anti-HBs titration and neutralizing experiments using hepatitis B surface antigen (HBsAg) from different genotypes specified the presence 3,300 IU/L anti-HBs in the blood of the donor highly capable of neutralizing HBsAg from different genotypes. Parts of the HBV DNA detected in the