Ileal mass-like lesion induced by Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis in a patient with aplastic anemia.

Hemophagocytic lymphohistiocytosis (HLH) is a rare life-threatening hyperinflammatory syndrome characterized by activated macrophages engulfing erythrocytes, leukocytes, platelets, and their precursor cells in bone marrow, liver, spleen, or lymph nodes. We report a case of Epstein-Barr virus (EBV)-associated HLH unusually presenting as an ileal mass. A 23-year-old man presented initially with persistent fever unresponsive to antibiotics and pancytopenia. A bone marrow aspiration and biopsy were used to diagnose the patient with aplastic anemia and HLH. A relatively well-defined low-density mass was radiologically noted in the terminal ileum, along with enlarged lymph nodes, and was suspected to be malignant lymphoma or an abscess. The ileocecectomy specimen revealed a transmural hemorrhagic infarction with numerous activated macrophages phagocytosing erythrocytes, plasma cells, and lymphocytes, and he was diagnosed with EBV-associated HLH. The patient received an allo-unrelated peripheral blood stem-cell transplantation and expired due to graft-versus-host disease following liver failure. The present case is very unique, in that EBV-associated HLH presented with an unusual ileal mass resulting from hemorrhagic infarction in a patient with aplastic anemia, suggesting variability in the biological behavior of EBV-associated disease.