Hemophagocytic syndrome: pitfalls in its diagnosis.

The hemophagocytic syndrome (HS) is characterized by a clinical picture of fever, hepatosplenomegaly, lymphadenopathy and peripheral pancytopenia. The morphologic hallmark of this syndrome is the phagocytosis of hematopoietic elements by morphologically normal macrophages. HS is considered rare and may be a primary disease or associated to viral, infection, neoplasias or autoimmune diseases. Treatment is controversial and its evolution is often fatal. Anatomo-pathological evaluation shows the phenomenon of hemophagocytosis in several organs, especially the hematopoietic tissues. We describe a case of HS, discuss its possible causes, its clinical and pathologic features, its pathophysiology and therapeutic possibilities.