The erythropoietin test measures the amount of hormone called erythropoietin (EPO) in blood. The hormone tells stem cells in the bone marrow to make more blood cells. EPO is made by cells in the kidney. These cells release more EPO when the blood oxygen level is low.
Risks associated with having blood drawn are slight, but may include:
Fainting or feeling lightheaded
Hematoma (blood accumulating under the skin)
Infection (a slight risk any time the skin is broken)
Is erythropoietin available as a prescribed medication?
Yes. Using recombinant DNA technology, erythropoietin has been synthetically produced for use as a treatment for persons with certain types of anemia. Erythropoietin can be used to correct anemia by stimulating red blood cell production in the bone marrow in these conditions. The medication is known as epoetin alfa (Epogen, Procrit) or as darbepoetin alfa (Arnesp). It can be given as an injection intravenously (into a vein) or subcutaneously (under the skin).
What organ produces erythropoietin?
Erythropoietin is produced to a lesser extent by the liver. Only about 10% of erythropoietin is produced in the liver. The erythropoietin gene has been found on human chromosome 7 (in band 7q21). Different DNA sequences flanking the erythropoietin gene act to control liver versus kidney production of erythropoietin.
INTERPRETATION OF RESULTS:
The normal range is 2.6 to 18.5 milliunits per milliliter (mU/mL).
What Abnormal Results Mean
Increased EPO level may be due to secondary polycythemia. This is an overproduction of red blood cells that occurs in response to an event such as a low blood oxygen level. The condition may occur at high altitudes or, rarely, because of a tumor that releases EPO.
Lower-than-normal EPO level may be seen in chronic kidney failure, anemia of chronic disease, or polycythemia vera.
Why the Test is performed?
This test may be used to help determine the cause of anemia, polycythemia (high red blood cell count) or other bone marrow disorders.
A change in red blood cells will affect the release of EPO. For example, people with anemia have too few red blood cells, so more EPO is produced.