After the introduction of dialysis and kidney transplants, the use of erythropoietin therapy is seen as one of the major advances in the treatment of chronic renal failure.
Longstanding kidney failure (chronic renal failure) is characterized by anaemia, where you have insufficient red blood cells. These blood cells carry oxygen to your body and vital organs like your heart and brain.
EPO in kidneys
The anemia in renal failure is due to many factors but is principally caused by the decreased production of an important hormone called erythropoietin (EPO). This hormone stimulates the bone marrow to make more red blood cells. The kidneys produce 90 % of your erythropoietin, therefore a loss of functional kidney cells will lead to anemia.
Iron, folic acid and vitamin B12 deficiencies that can occur with chronic disease, also cause anaemia, and must be addressed as well. Haemodialysis can contribute to anaemia due to loss of blood cells during the procedure and decreased survival of the red blood cells. The latter is thought to be caused by high levels of urea (the breakdown product of protein), and possibly by the effects of haemodialysis.
Patients with CRF take aluminum-containing phosphate binders with every meal. The failed kidneys are unable to regulate this mineral and high levels of phosphate cause calcium to be drawn from your bones. Although the phosphate binders are essential, it can contribute to anaemia because of the aluminum content. However, other phosphate binders that do not contain aluminum are available and are more widely used.
Treating anaemia in CRF
Iron, folic acid and vitamin B12 is needed to make blood, and deficiencies are corrected if applicable. Dialysis helps in the long term and blood transfusions may be necessary although it poses certain risks. Erythropoietin therapy is very effective and is used increasingly. It can be given intravenously or under the skin depending on the patient’s condition.
Benefits of treatment
Treating anaemia improves the oxygen-carrying ability of the blood and improves quality of life. Exercise capacity and certain mental functions like concentration, improves. Some patients also report better sleeping habits, appetite and libido.
Side effects of EPO therapy
EPO is a very safe treatment. The most common side effect seems to be raised blood pressure. This can be limited by adjusting the dose and careful monitoring. Severe elevations of blood pressure can occur and headaches, visual disturbances and nausea must be reported immediately. Other minor side effects include flu-like symptoms, joint and muscle discomfort, fever, headaches, skin rash and skin reaction at the site of the injection.