Abstract
Post-transplant lymphoproliferative disorder (PTLD) is a well-recognized complication of organ transplantation. Progress has recently been made in the pathological classification of PTLD. However, the clinical course has not been clarified because of the rarity of this disease. We experienced a case of PTLD with a fulminant clinical course. The patient had been under longterm immunosuppressive treatment for aplastic anemia. He received related allogeneic hematopoietic stem cell transplantation. Soon after transplantation, he developed PTLD. According to the guidelines, we reduced immunosuppression. However, the disease course was so fulminant that there was no time for the patient to respond, and he died of multi-organ failure. There may be various clinical types of PTLD, which may include some fulminant cases. In such a case, it is not sufficient to reduce immunosuppression. The patient should be carefully observed and an appropriate individual treatment should be chosen.