Reactive haemophagocytic syndrome in children

Reactive haemophagocytic syndrome is characterized by activation and uncont rolled non-malignant proliferation of T lymphocytes and macrophages, leadin g to a cytokine overproduction, which accounts for the main biological sign s. Children usually present with an acute febrile illness, fulminant pancyt openia and hepatosplenomegaly: posing a problem of differential diagnosis w ith severe sepsis. Hemopoietic cells are actively ingested by monocytes/mac rophages in various organs, including lymph nodes, bone marrow liver and sp leen. This exarcerbation of the histiocytic system is currently classified among the reactional histiocytoses. If reflects an inappropriate host immun e response, Most patients have a known underlying disease (hemopathy lupus, systemic juvenile arthritis, HIV infection). In the few cases that occur i n the apparent absence of any risk factors, investigations should be made t o look for predisposing inherited diseases, such as familial lymphohistiocy tosis or Purtilo's disease in boys. The treatment rests on immunosuppressiv e agents followed by bone marrow transplantation which can provide a defini tive cure in genetic forms. (C) 2000 Editions scientifiques ef medicales El sevier SAS.