Chronic active Epstein-Barr virus infection and virus-associated hemophagocytic syndrome.

We describe two unusual cases of Epstein-Barr virus infection that were complicated by the virus-associated hemophagocytic syndrome, predominantly involving the spleen. Both patients were young adult men who presented with fever, pancytopenia, and hepatosplenomegaly. Both had prompt symptomatic and hematologic improvement following splenectomy. Severe constitutional symptoms recurred in one patient 1 month after splenectomy, and he died of septicemia 2 months later. In both cases, there was prominent hemophagocytosis in the splenic red pulp. Some hemophagocytosis was also noted in the liver from the fatal case. Unexpectedly, no hemophagocytosis was detected in the bone marrow biopsy specimens or marrow aspirates obtained from these patients. The DNA hybridization studies detected Epstein-Barr virus genomes in spleen samples from both patients, and both patients had atypical patterns of serologic response to the virus, suggesting that a defective immune response may lead to an unrestrained viral proliferation. We conclude that there is an association between chronic active Epstein-Barr virus infection and the hemophagocytic syndrome, but that the tissue distribution of the hemophagocytosis may be variable.