Early onset of hemophagocytic syndrome following allogeneic bone marrow transplantation.

We report a 40-year-old man who presented with acute onset of hemophagocytic syndrome (HPS) after allogeneic bone marrow transplantation (alloBMT) for acute myelogenous leukemia. On day 8 after alloBMT, the patient suddenly manifested high-grade fever, transfusion-resistant severe anemia, and thrombocytopenia. Neither veno-occlusive disease nor thrombotic microangiopathy was documented. The level of ferritin in serum was elevated to 1192 ng/mL. A bone marrow aspiration test on day 16 showed a markedly increased number of activated macrophages showing massive hemophagocytosis. Serum levels of interferon-gamma, soluble interleukin-2 receptor, interleukin-6, tumor necrosis factor-alpha, and macrophage colony-stimulating factor (M-CSF) were elevated. From these findings, we determined his transfusion-resistant cytopenias to be attributable to HPS. No viruses (including cytomegalovirus, Epstein-Barr virus, human herpes-virus-6, parvovirus B19, and adenovirus B11) were detected in serum or urine by polymerase chain reaction amplification. We speculate that in addition to the administration of M-CSF, hypercytokinemia during the early phase post-alloBMT might have contributed to the onset of HPS in this patient. Methylprednisolone pulse therapy was very effective for the treatment of the HPS. This case reveals that HPS could develop after alloBMT, even when engraftment of hematopoietic cells is not confirmed.