Anemia

Blood is composed of red blood cells, white blood cells, platelets and plasma. Anemia is blood which is low in red blood cells and is common in people with kidney disease. Red blood cells carry oxygen to tissues and organs throughout your body. Without oxygen, your tissues and organs, particularly the heart and brain, may not do their jobs as well as they should. People with anemia usually tire easily, look pale and may be short of breath.

Healthy kidneys produce a hormone called erythropoietin (EPO) which stimulates the bone marrow to produce the proper number of red blood cells needed to carry oxygen to vital organs. Diseased kidneys don't make enough EPO. As a result, the bone marrow makes fewer red blood cells.

Other common causes of anemia include loss of blood and low levels of iron and folic acid.

Anemia prevents many people with kidney disease from feeling their best. Appropriate treatments will help patients feel better, live longer, and have more energy.

Laboratory Tests

A complete blood count (CBC) is a laboratory test performed on a sample of blood. It measures the amount of hemoglobin (Hgb) in the blood which is the component of red blood cells that carry oxygen.

When Anemia Begins

Anemia may begin to develop in the early stages of kidney disease when you still have 20 to 50 percent of your normal kidney function. Anemia tends to worsen as kidney disease progresses.

Diagnosis

If you have a Hgb of 11 or less, you are considered anemic with the most likely cause being decreased EPO production. An evaluation by a physician is necessary and will include tests for iron deficiency and blood loss in the stool to be certain there are no other reasons for the anemia.

Treatment

• EPO - EPO deficiency can be treated with a genetically engineered form of the hormone which is usually injected under the skin. Hemodialysis patients who can't tolerate EPO shots may receive the hormone intravenously during treatment, but this method requires a larger, more expensive dose and may not be as effective. DOQI recommends that patients treated with EPO therapy should achieve a target Hgb of 11 to 12 g/dL.
• Iron - Many people with kidney disease need both EPO and iron supplements to raise their Hgb to a satisfactory level. If your iron levels are too low, EPO won't help and you'll continue to experience the effects of anemia. You may be able to take an iron pill, but many studies show that iron pills don't work as well in people with kidney disease as iron given intravenously.
  
  In addition to measuring your Hgb, two other measurements can be taken to show whether you have enough iron:
  • Ferritin levels indicate the amount of iron stored in the body.
  • TSAT stands for transferrin saturation, a test that indicates how much iron is available to make red blood cells.