[Hemophagocytic syndrome: an underestimated cause of the syndrome of non-infectious fever?].

Haemophagocytic syndrome (HM) is a severe disorder with characteristic clinical and biological features. The case of a patient with malignant lymphoma who experienced HM during Herpes virus I pulmonary infection is reported. Main clinical, biologial and pathological findings are described. The risk of underestimation of this disease in patients requiring intensive care as well as the absolute necessity of an early diagnosis are emphasised.