Levels of erythropoietin in patients with the anemias of chronic diseases and liver failure.

Two mechanisms are felt to be responsible for the production of anemia in patients with chronic diseases. The first is failure to produce adequate amounts of erythropoietin (EP), and the second is failure to deliver iron to the bone marrow in amounts sufficient to support normal erythropoiesis. In order to evaluate these hypotheses we studied urine and serum EP levels and levels of 2,3-diphosphoglycerate in normal subjects, in patients with the anemia of chronic diseases, in patients with chronic liver disease, and in patients with a variety of other anemias. Based on the results, we propose first that insufficient production of EP is one of the major mechanisms responsible for anemia in patients with chronic diseases. Second, insufficient production of EP is, in part, responsible for anemia seen in patients with chronic liver disease. Third, serum and urine EP levels decrease with aging, and this correlates with the fall of hemoglobin levels seen in older normal subjects.