EBM Consult

Lab Test: Erythropoietin, EPO Level (Blood)

    Lab Test
    • Erythropoietin (Blood) EPO level
    Description
    • Serum or plasma erythropoietin levels used in the differential diagnosis of certain disorders of erythrocyte production
    Reference Range
    • Adults:  5-36 international units/L
    Indications & Uses
    • Anemia in diabetes mellitus with suspected subclinical renal impairment - impaired erythropoietin production in the presence of declining hemoglobin levels may contribute to anemia in diabetic patients. 
    • Differential diagnosis of polycythemia - increased EPO levels are highly correlated with secondary disease.  Normal EPO levels suggest relative polycythemia.  Decreased EPO levels are consistent with polycythemia versa.
    Clinical Application
    • Erythropoietin is a glycoprotein hormone produced in the peritubular interstitial cells located in the inner cortex of the kidney in response to decreased oxygen sensed by these renal cells and perhaps the carotid body cells, the production of EPO is increased.  EPO then goes on to stimulate the bone marrow to increase RBC production, which will improve oxygenation in the kidney, and the stimulus for EPO is reduced.  This feedback mechanism is very sensitive to minimal persistent changes in oxygen levels.  In patients with normal renal function, EPO levels are inversely proportional to the hemoglobin concentration. 
    • Morning erythropoietin values may be higher than afternoon values because of diurnal secretory patterns. 
    • Increased levels may indicate:
      • Iron-deficiency anemia, megaloblastic anemia, hemolytic anemia, myelodysplasia, chemotherapy, acquired immunodeficiency syndrome (AIDS), pheochromocytoma, renal cell carcinoma, or adrenal carcinoma. 
    • Decreased levels may indicate:
      • Polycythemia vera or renal diseases and real failure.
    Related Tests
    • Hemoglobin - EPO is inversely proportional to hemoglobin levels.
    • Reticulocyte count - this is an important blood test that also is used in differentiating the causes of anemia and polycythemia.
    Drug-Lab Interactions
    • Pregnancy is associated with elevated EPO levels. 
    • The use of transfused blood decreases EPO levels.
    • Drugs that increase EPO levels include:  ACTH, birth control pills and steroids.
    Test Tube Needed
    • EDTA containing (lavender top) tube* (PDR)
    • Red top or gel separator tube
    Procedure
    • Collect 5 mL of venous blood. 
    • Apply pressure or a pressure dressing to the venipuncture site and observe the site for bleeding.
    What To Tell Patient Before & After
    • Explain the procedure to the patient.
    References
    • LaGow B et al., eds. PDR Lab Advisor. A Comprehensive Point-of-Care Guide for Over 600 Lab Tests.  First ed. Montvale, NJ: Thomson PDR; 2007.
    • Pagana K, Pagana TJ eds. Mosby's Manual of Diagnostic and Laboratory Tests. 5th Ed.  St. Louis, Missouri. 2014.

MESH Terms & Keywords

  • Erythropoietin, EPO