同種造血幹細胞移植後のHBV再活性化の単施設後方視的検討

Reactivation of hepatitis B has been recognized as a careful adverse event after chemotherapies or immunosuppressive therapies because chronic hepatitis B leads to carcinoma and/or liver cirrhosis. Allogenic hematopoietic stem cell transplantation（allo-HSCT）against hematological diseases induces severe immunosuppression including reconstitution of naïve donor immunity against HBV-infected hepatocytes and we therefore need to follow-up HBV testing for a long term. In order to establish how to follow-up HBV-infected patients with receiving allo-HSCT, we retrospectively studied HBV serological markers and HBV-DNA in the HBV-infected patients, who received allo-HSCT and followed-up more than １ year in our single center. We detected ７ HBV-infected and allo-HSCT-received patients, and HBV reactivation was occurred in ３ patients with detecting HBV-DNA. No patients were died due to HBV reactivation. The HBV reactivation period after receiving allo-HSCT was １６，２０，７９ months, respectively. All the ３ patients received nucleoside analogues（NUCs）; however, the appearance of viral mutation was occurred in one patient who received lamivudine and already detected HBs-Ag before allo-HSCT. The HBV reactivation was controlled with addition of adefovir. Others were due to discontinuation of entecavir, which reason was poor medication-adherence after stopping immunosuppressive therapies. These two patients received tenofovir alafenamide in addition or retreated with entecavir, respectively, leading to disappearing of HBV-DNA. HBs-Ab were disappeared in ３１ months after allo-HSCT in one patient, and then the Ab was detected after occurring HBV reactivation, suggesting reconstitution of donor immunity. Taken together, our findings suggest that we need to follow-up immune-reconstitution and regularly evaluate HBV serological markers and HBV-DNA, in addition to maintain medication-adherence.