Causes of Anemia in Chronic Renal Failure
In people with chronic renal failure, anemia can develop due to the kidneys’ failure to produce sufficient amounts of a hormone called erythropoietin. Erythropoietin, or "EPO," assists the body’s bone marrow in manufacturing red blood cells. Hemoglobin molecules within the red cells carry oxygen to tissues and organs throughout the body.
Signs and Symptoms of Anemia Due to Kidney Failure
In someone with chronic renal failure, anemia manifests itself in several ways. Individuals may experience weakness, paleness, lack of energy or concentration. They may be dizzy or experience a loss of blood pressure when standing. Anemia can develop in the earliest stage of chronic kidney disease, called chronic renal insufficiency. In this stage, the kidneys will have between 20 percent and 50 percent of their normal function. In the early stages of kidney disease, a person may not even realize they have anemia. They may attribute their low energy levels to poor diet or lack of rest.
Chronic kidney disease is progressive and irreversible. When the kidneys have 10 percent function remaining, then dialysis or transplantation becomes necessary. This is called end-stage kidney failure. Anemia worsens when the kidneys form scar tissue during the disease process and EPO production decreases even further.
Diagnosis and Treatment
Diagnosis of anemia in chronic renal failure is accomplished through a complete blood count or "CBC," which measures hemoglobin and hematocrit (percentage of red blood cells in the blood) levels, as well as the number of red and white blood cells and platelets in the blood. The doctor may also check the patient’s heart and lungs. Shortness of breath or irregularities in heart beat can be indicative of anemia.
The hormone erythropoietin can now be genetically engineered and administered to treat kidney patients with anemia. Doctors commonly use one of two variations of the synthetic hormone, called epoetin alfa and darbepoetin, during treatment. The hormone is injected under the skin or administered intravenously in those who cannot tolerate shots.
A physician will also check a patient’s iron levels. The hormone EPO will not make blood cells if iron levels are too low. Iron supplements are given intravenously or through the tube used during dialysis to return blood to the body. Vitamin B12 and folic acid supplements may also be recommended. Gastrointestinal bleeding, infection or chronic inflammatory diseases can also cause anemia in individuals.
Advances in Research Help Those With Renal Failure Anemia
Prior to 1990, when the hormone EPO was first approved for treating anemia in those with renal disease, patients were relegated to receiving frequent blood transfusions and testosterone treatments. The development and use of EPO in renal disease patients has improved hematocrit levels and provided those suffering from renal failure with a renewed sense of energy and well being.
National Kidney and Urologic Diseases Information Clearinghouse: Anemia in Kidney Disease and Dialysis – www.kidney.niddk.nih.gov/kudiseases/pubs/anemia/#hope
The Foundation forr IgA Nephropathy: Chronic Renal Insufficiency – www.igan.ca/id76.html
National Hematologic Information Services: Anemia of Inflammation and Chronic Disease – www.hematologic.niddk.nih.gov/pubs/AnemiaChronic/index.htm