免疫抑制・化学療法によるB型肝炎発症予防における薬剤師の介入効果

－化学療法施行時および終了後のフォローアップ体制構築とその評価－

抄録

Hepatitis B arising from hepatitis B virus (HBV) reactivation following chemotherapy or hematopoietic stem cell transplantation has a high risk of mortality. In January 2013, we began checking the HBV screening results of all patients scheduled to undergo chemotherapy. Furthermore, it has been reported that hepatitis B following HBV reactivation may develop even after chemotherapy has been completed. As yet, pharmacists have not been involved in preventive measures against HBV reactivation after the completion of chemotherapy. To address this, we constructed a HBV test confirmation system. In November 2013, we began checking the intervals and results of HBV-DNA tests in the 12 months following the completion of chemotherapy in patients with resolved HBV (hepatitis B surface antigen (HBs-Ag) negative and hepatitis B surface antibody (HBs-Ab) positive and/or hepatitis B core antibody (HBc-Ab) positive). We compared the implementation rate of HBV marker testing before and after initiating our approach. The implementation rate of blood testing for HBs-Ab/HBc-Ab in all patients scheduled to undergo chemotherapy rose significantly to 91％/95％, respectively, from 27％/27％ (P < 0.001). In addition, the implementation rate of HBV-DNA testing after the completion of rituximab-steroid combination therapy in patients with resolved HBV rose significantly to 69％ from 27％ (P < 0.001). The rate after hematopoietic stem cell transplantation rose to 64％ from 25％. In conclusion, such an approach by pharmacists is useful as a preventive measure against hepatitis B arising from HBV reactivation.