Markedly high plasma erythropoietin and granulocyte-colony stimulating factor levels in patients with paroxysmal nocturnal hemoglobinuria.

In patients with paroxysmal nocturnal hemoglobinuria (PNH), we measured plasma concentrations of endogenous hematopoiesis-regulatory cytokines to characterize bone marrow (BM) hypoplasia which is a major cause of death. Contrary to 10 healthy individuals, all 14 patients with PNH showed increases of erythropoietin (Epo) and granulocyte-colony stimulating factor (G-CSF). There were no signs of infection, renal dysfunction or hypoxia. The lower the hemoglobin level and granulocyte count, the higher the plasma Epo and G-CSF levels. In contrast, marked differences were not found in the levels of interleukin-3 (IL-3), tumor necrosis factor-alpha (TNF-alpha), stem cell factor (SCF), granulocyte/macrophage-colony stimulating factor (GM-CSF), or interferon-gamma) (IF-gamma). The cytokine profiles of PNH patients were quite similar to those of patients with aplastic anemia (AA) and myelodysplastic syndrome (MDS). The cytokine profiles may support a pathological relationship between PNH and these stem cell disorders.