Granulocyte-monocyte colony-stimulating factor levels during hemodialysis-induced leukopenia.

Hemodialysis (HD), especially with cellulosic membranes, leads regularly to a transient but marked drop of peripheral neutrophils. Such neutropenia during the initial 10-30 min of HD is followed by a reincrease in granulocyte count up to a mild leukocytosis. Although this phenomenon accounts for the best documented side effect of HD, little is known about the underlying regulatory mechanisms. Therefore in this study the blood levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) were measured during HD. Previous investigations have demonstrated that GM-CSF plays the central role in controlling the homeoiostasis of leukocytes by up- and downregulation of proliferation and efflux of cells out of the maturation compartment within the bone marrow. Three patients with chronic renal failure underwent HD with cuprophane membranes. In all cases a significant drop of peripheral granulocytes occurred, but GM-CSF levels remained unchanged and were found in the normal range during the whole period of the treatment. It is therefore concluded that GM-CSF may not be significantly involved in the regulation of peripheral leukocytes during HD.