| Field Name |
Data Description |
| Test Name |
Erythropoietin |
| Code |
Erythropoietin Level. |
|
CPT Code |
82668 |
| Last Modified |
4/18/2018 3:32:00 PM |
| Test Name |
Erythropo. |
| Synonyms |
EPO, Epogen, Procrit, Epoetin Alfa, rHuEPO-ALPHA |
| Patient Preparation |
|
| Spec. Requirements |
Blood |
| Tube |
Gold or Red |
| Collection Volume |
3.5 mL Gold or 4.0 mL Red |
| Storage |
Ambient,Refrigerated, or Frozen 14 days |
| Routine TAT |
|
| STAT TAT |
N/A |
| Days Test Performed |
|
| Performed by BHS |
None |
| See Availability |
|
| Reference Lab |
LabCorp of America |
| Reference Lab Code |
140277 Erythropoietin (EPO), Serum |
| Clinical Use |
This test is intended as an aid in the diagnosis of anemias and polycythemias. With the advent of the administration of recombinant erythropoietin as a biologic therapy to increased blood cell mass, an erythropoietin assay may be used also to aid in the prediction and monitoring of response to recombinant erythropoietin treatment of anemia. Erythropoietin (EPO), a glycoprotein (~30,400 Daltons) produced primarily by the kidney, is the principal factor regulating red blood cell production (erythropoiesis) in mammals. Renal production of is regulated by changes in oxygen availability. Normally, EPO levels vary inversely with hematocrit. Under conditions of hypoxia, the level of EPO in the circulation increases leading to increased production of red blood cells. Conversely, a high hematocrit should suppress the release of EPO. The over-expression of EPO may be associated with certain pathophysiological conditions. Primary polycythemia (polycythemia vera) is a neoplastic (clonal) blood disorder characterized by EPO-independent, autonomous production of erythrocytic progenitors from abnormal bone marrow stem. Conversely, various types of secondary polycythemias are associated with the production of elevated levels of EPO. The overproduction of EPO may be an adaptive response associated with conditions that produce tissue hypoxia, such as living at a high altitude, chronic obstructive pulmonary disease, cyanotic heart disease, sleep apnea, high oxygen affinity hemoglobinopathy,smoking, or localized renal hypoxia. In other instances, elevated EPO levels are the result of production by neoplastic cells. Tumors that have been associated with an inappropriate EPO production include cerebellar hemangioblastomas, uterine leiomyomas, pheochromocytoma, renal cell carcinoma, hepatocellular carcinoma, parathyroid adenomas and meningiomas. Deficient EPO production is found in conjunction with certain forms of anemias. These include anemia of renal failure, end-stage renal disease, hypothyroidism and malnutrition. EPO levels are often measured in patientswith chronic kidney disease to assess the kidneys' continued ability to produce erythropoietin. Anemias of chronic disease (chronic infections, autoimmune diseases, rheumatoid arthritis, AIDS, malignancies), are characterizedby a blunted response of erythroid progenitors to EPO. Otherforms of anemias can be associated with EPO-independent causes and affected individuals show elevated levels of EPO.These forms include aplastic anemias, iron deficiency anemias, thalassemia, megaloblastic anemias, pure red cell aplasias, and myelodysplastic syndromes. |
| Reference Range |
|
| Critical Value |
|
|
Component |
|
|
Reference Range |
|
|
Critical Value |
|
 |
|
| Testing Sample Type |
Serum |
| Min Lab Testing Volume |
0.5 mL |
| Special Handling |
|
| Lab Notes |
|
| Methodology |
IC - Immunochemiluminometric Assay |
| Limitations |
Erythropoietin (EPO) levels alone cannot reliably distinguish between primary and secondary polycythemia; EPO levels are within normal limits in some patients with primary polycythemia. People living at high altitudes may have higher EPO levels than people living at lower altitudes. This assay cannot distinguish between endogenous and exogenous EPO. There is some diurnal variation in EPO levels. For optimal results in serial patient monitoring, all specimens should be collected at the same time of day. For assays employing antibodies, the possibility exists for interference by heterophile antibodies in the patient sample. Patients who have been regularly exposed to animals or have received immunotherapy or diagnostic procedures utilizing immunoglobulins or immunoglobulin fragments may produce antibodies, eg, HAMA, that interfere with immunoassays. Additionally, other heterophile antibodies (such as human anti-goat antibodies) may be present in patient samples. Such interfering antibodies may cause erroneous results. Carefully evaluate the results of patients suspected of having these antibodies. Because results obtained with one commercial EPO assay may differ significantly from those obtained with any other, it is recommended that any serial testing performed on the same patient over time should be performed with the same commercial EPO test. Lower EPO levels than expected have been seen with anemias associated with the following: rheumatoid arthritis, acquired immunodeficiency syndrome, cancer, and ulcerative colitis, sickle cell disease, and in premature neonates |
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