[Successful treatment of secondary graft failure with donor lymphocyte infusion in a post-allogeneic stem cell transplant acute myeloid leukemia patient].

Here we report a case of secondary graft failure that was effectively treated with donor lymphocyte infusion (DLI). A 64-year-old female patient with acute myeloid leukemia obtained partial remission with azacitidine therapy and subsequently underwent unrelated allogeneic bone marrow transplantation (BMT). After confirming successful engraftment and achieving complete remission with incomplete blood count recovery, she was subsequently followed up at an outpatient clinic. A routine test performed by day 110 after BMT revealed the presence of pancytopenia. A bone marrow aspirate did not reveal any evidence of disease relapse or hemophagocytic syndrome but demonstrated hematopoietic insufficiency. Donor chimerism also declined over time; thus, the patient was diagnosed with secondary graft failure. Supportive treatment, including granulocyte-colony stimulating factor and blood transfusion, failed to improve the blood parameters. Because the patient refused a second BMT, we performed DLI on day 147 after BMT (CD3+ cells: 1.0×107/kg, single dose). Consequently, the blood cell count improved promptly and dramatically without adverse events. Following this, we discussed the case and analyzed the related literature.