The man had no previous medical history and was admitted to a hospital with pancytopenia after a recent viral illness. During his hospitalization, he developed sudden abdominal distension and hypotension. Surgical exploration of his abdomen revealed a ruptured spleen. The spleen was removed, but the patient did not survive the operation. After reviewing the clinical history, autopsy, and microscopic sections, the cause of death was determined to be VAHS, a generalized histiocytic proliferation and marked hemophagocytosis associated with a systemic viral infection. Clinically, VAHS presents as pancytopenia and organomegaly, and it is often confused with malignant histiocytosis. Organs most affected in VAHS are bone marrow, lymph nodes, spleen, and liver. It is concluded that VAHS should be included in the differential diagnosis of spontaneous or nontraumatic rupture of the spleen. 95 references, 3 tables, and 5 figures