Fatal hematophagic histiocytosis after granulocyte-macrophage colony-stimulating factor and chemotherapy for high-grade malignant lymphoma.

Fatal hematophagic histiocytosis occurred in two patients after they had received granulocyte-macrophage colony-stimulating factor (GM-CSF) in addition to chemotherapy for malignant non-Hodgkin's lymphoma. In one patient GM-CSF promoted the activity of subclinical hematophagic histiocytosis, resulting in severe pancytopenia and multiorgan failure. In the other patient the syndrome that caused persistent bone marrow failure began after the institution of GM-CSF therapy. Exogenous GM-CSF appears to upregulate preexisting hematophagic histiocytosis and may even contribute to its de novo initiation. It is therefore conceivable that endogenous GM-CSF also plays an essential role in the pathogenesis of this syndrome.