title: Sickle cell anemia patients have low erythropoietin levels for their degree of anemia.
abstract: We have studied serum immunoreactive erythropoietin (SIE) levels in 28 patients with sickle cell anemia (SCA) without renal insufficiency and in 17 patients with nonhemoglobinopathy anemias of comparable severity using a sensitive radioimmunoassay procedure. An exponential relationship between SIE level and degree of anemia was noted in all patients. However, in nonhemoglobinopathy anemia, a sharp rise in the SIE level occurred as hemoglobin (Hb) levels fell below about 12 g/dL, whereas in sickle cell patients the increase was not marked until hemoglobin fell to about 9 g/dL. The response was more blunted in older SCA patients than in younger ones. A linear regression model relating SIE level to Hb level, presence/absence of SCA, and age explained 63% of the variation in SIE. We conclude that the serum erythropoietin levels in SCA increased at a lower hemoglobin concentration and are of a lower magnitude than that of the other anemias.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000755:Anemia, Sickle Cell / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D004921:Erythropoietin / Q000097:blood*; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D007223:Infant; D007674:Kidney Diseases / Q000097:blood
chemical_list: D006454:Hemoglobins; D004921:Erythropoietin