Erythropoietin, Serum

About this test

This test measures the erythropoietin (EPO) level in blood. EPO is a hormone that kidney makes to trigger bone marrow to make red blood cells. A normal EPO level means that your body can make healthy red blood cells.

You may need this test if other tests have shown that you have anemia, and your healthcare provider wants to figure out what kind of anemia you have. They might also order this test to help find out whether your kidneys are making a normal amount of EPO. A level of EPO that’s higher than normal may mean you have a kidney tumor.

Inappropriately high levels of erythropoietin can cause high levels of red blood cells (Polycythemia). Long-term (chronic) exposure to low levels of oxygen can increase EPO levels. Chronic kidney disease (CKD) is the most common cause of low EPO levels. Damaged kidneys can’t produce as much EPO, leading to low levels. CKD and low EPO levels can lead to anemia.

Other names – EPO, Erythropoetin, hematopoietin and hemopoietin, polycythemia, Anemia, Chronic kidney disease, CKD

Erythropoietin (EPO) helps make red blood cells (RBCs) which deliver oxygen to the tissues in body. Oxygen turns into energy, and tissues release carbon dioxide.  Normally, when specialized cells in kidneys detect low blood oxygen levels, they increase the production of EPO. EPO then tells the spongy tissue inside bones (bone marrow) to make more red blood cells. When cells in your kidneys sense that there’s sufficient oxygen in your blood, they reduce the production of erythropoietin.