A case of acute myeloid leukemia with Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis successfully treated by cord blood transplantation

Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory life-threatening syndrome. Epstein-Barr virus (EBV) infection is a common cause of HLH. Occasionally, HLH develops with malignancies such as lymphoma. Concurrent cases of acute myeloid leukemia (AML) and EBV-associated HLH (EBV-HLH) are very rare, and the treatment has not been established. Hematopoietic stem cell transplantation (HSCT) is the only curative treatment for refractory HLH and high-risk AML. Consequently, HSCT would be a good treatment for cases of HLH and high-risk AML coexistence. A 66-year-old man was diagnosed with high-risk AML. After induction chemotherapy, he experienced prolonged pancytopenia, high fever, and elevated liver enzymes. A high EBV viral load was found, and he was diagnosed with EBV-HLH, with EBV infecting CD8⁺ T-cells. EBV-HLH was resolved by treatment with corticosteroids. Meanwhile, some hemophagocytosis remained after consolidation chemotherapy, and EBV-DNA in whole blood was positive. The patient received cord blood transplantation to treat both AML and EBV-HLH. His AML achieved complete remission, and the hemophagocytosis was in remission. However, his EBV viral load increased again 53 days after transplantation. Then, the EBV infection occurred in B-cells, and there was no relapse of hemophagocytosis. In conclusion, both AML and HLH were successfully treated by transplantation. This report highlights treatment strategies in specific cases of AML and EBV-HLH coexistence.