CPT® Code 82668

The CPT® Code 82668 refers to a laboratory test specifically designed to measure the level of erythropoietin (EPO) in the serum. EPO is a crucial hormone predominantly produced by the kidneys, which plays a vital role in the regulation of red blood cell production. When blood oxygen levels are low, the kidneys respond by increasing the production of EPO, which is then transported to the bone marrow. In the bone marrow, EPO stimulates hematopoietic stem cells to enhance the production of red blood cells (RBCs), thereby improving oxygen delivery throughout the body. The measurement of serum EPO levels is significant as it can provide insights into various hematological conditions. For instance, abnormal EPO levels can indicate kidney damage or disorders affecting the bone marrow. This test is particularly useful as an initial screening tool for conditions such as polycythemia, which is characterized by an increased number of red blood cells, and for differentiating between various types of anemia. Additionally, it helps in assessing a patient's eligibility for erythropoietin therapy, especially in cases of chronic renal failure. Elevated EPO levels, when accompanied by low hematocrit (HCT) levels, may suggest conditions like iron deficiency anemia or aplastic anemia. Conversely, elevated EPO levels with normal HCT can indicate renal transplant rejection or the presence of benign or malignant kidney tumors. On the other hand, decreased EPO levels may be observed in conditions such as hemochromatosis, while decreased EPO levels alongside elevated HCT are indicative of polycythemia vera. In patients with HIV undergoing AZT therapy, decreased EPO levels are often found in conjunction with decreased HCT. The test is performed on a blood sample obtained through a separately reportable venipuncture, and the serum or plasma is analyzed using a quantitative chemiluminescent immunoassay method.