[Lymphohistiocyte activation syndromes associated with Epstein-Barr virus]

Lymphohistiocyte activation syndromes associated with the Epstein-Barr virus and characterized by activation and proliferation of T-cells and macrophages reflecting an inappropriate response of the host to the viral infection. The clinical manifestations are often alarming symptoms suggestive of severe sepsis. Most patients have a known underlying disease (hemopathy, lupus, Still's disease, HIV infection, bone marrow or organ transplantation). In the few cases that occur in the apparent absence of any risk factors, investigations should be done to look for a predisposing inherited disease, such as familial lymphohistiocytosis of Purtilo syndrome in boys. The treatment rests on immunosuppressive agents followed by bone marrow transplantation, which can provide a definitive cure in genetic forms.