Transferrin saturation measures iron bound to transferrin in the blood. Transferrin carries iron to bone marrow for red blood cell production. Hemoglobin, which carries oxygen, contains four iron ions. Low iron levels cause anemia, while high levels can indicate hemochromatosis. Transferrin saturation is calculated using serum iron levels and total iron binding capacity, with normal percentages ranging from 15% to 50%.
Transferrin saturation is a calculated value resulting from a medical laboratory test to measure the amount of iron bound to transferrin in the blood. The liver produces transferrin, which is a protein that serves to bind iron molecules and transports them through the bloodstream to the bone marrow.
Iron is an important component of the hemoglobin molecule found in red blood cells. Hemoglobin is made up of four polypeptide chains and each chain contains a heme group. Heme is a pigment and contains an iron ion at its core. There are four heme molecules and four iron ions bonded to the polypeptide chains of the hemoglobin molecule.
Each iron ion can bind to one oxygen molecule, making hemoglobin a carrier for four oxygen molecules. When oxygen is absorbed by the lungs, it binds to these iron ions. Oxygen is then transported through the body via red blood cells. As blood flows through the capillaries, oxygen is released from the iron ion and is absorbed into the cells.
Red blood cells cannot grow and divide and supply oxygen to body tissues for about four months before they begin to break down. Iron is released from red blood cells, but cannot circulate freely in the bloodstream. Transferrin picks up the iron ions and takes them back to the bone marrow to be recycled into new red blood cells.
If blood iron levels are too low, a patient could suffer from anemia. Because the body’s tissues are not getting enough oxygen, the patient may experience fatigue, weakness, and pale skin color. Elevated iron levels can mean that the patient may have a condition known as hemochromatosis. Iron buildup in tissues and organs can be harmful. If a doctor suspects a patient has anemia or iron overload, a transferrin saturation test will be ordered.
Transferrin saturation is reported as a percentage of transferrin saturated with iron. Serum iron levels and total iron binding capacity (TIBC) are two tests performed on blood and their results are used to calculate this value. A serum iron level in the range of 60-170 micrograms/deciliter (mcg/dL) or 10-30 micromol/liter (umol/L) is considered normal. TIBC refers to the amount of iron that would be required to bind all of the transferrin in the blood.
Normal TIBC values range from 240-450 mcg/dL (43-80.6 umol/L). The serum iron level divided by the total iron binding capacity multiplied by 100 gives a transferrin saturation level. The calculated percentages normally range from 15% to 50%. Patients with anemia would have a low rate, while those with hemochromatosis would have a high rate.
Protect your devices with Threat Protection by NordVPN
