If the hemoglobin level does not increase after 12 weeks, erythropoietin should be discontinued. The predominant cause of anemia in renal disease is a deficiency of erythropoietin production by the diseased kidneys. If there is underlying inflammatory renal disease, there may be a component of anemia of chronic disease. Anorexia and poor iron intake, frequent blood sampling, and loss of erythrocytes during hemodialysis may produce iron deficiency. Depending on which processes are causing the anemia, the peripheral smear may show erythrocyte fragmentation or echinocytosis.
Aluminum toxicity can also cause an anemia in hemodialysis patients.
This anemia was initially identified in patients who had so-called dialysis dementia. Very high plasma aluminum levels probably result from aluminum contamination of the dialysis fluid or gastrointestinal absorption of the aluminum gels taken to bind dietary phosphates. Erythropoietin therapy can eliminate the transfusion requirement in patients on hemodialysis and in patients with progressive renal disease who do not yet require hemodialysis. Such treatment significantly improves their quality of life. Side effects, such as hyperkalemia and hypertension, occur infrequently.