Total iron binding capacity (TIBC, Anemia -TIBC) is a blood test to see if you have excessive or too little iron in your blood. Iron moves through the blood attached to a protein called transferrin. This test helps your health care supplier understand how well that protein can carry iron in your blood.
Taken together with serum iron and percent transferrin saturation clinicians usually perform this test when they are worried about anemia, iron deficiency or iron shortage anemia. However, due to the fact that the liver produces transferrin, modifications in function (such as cirrhosis, liver disease, or liver failure) need to be thought about when performing this test. It can also be an indirect test of liver function, but is seldom used for this function.
The percent transferrin saturation (i.e., the outcome of the formula of serum iron/TIBC x 100) can also be a beneficial indicator.
| Condition | Serum iron (highly variable) | Transferrin and TIBC | Percent transferrin saturation |
|---|---|---|---|
| iron deficiency anemia | Low | High. The liver produces more transferrin, presumably attempting to maximize use of the little iron that is available. | Low, as there is insufficient iron. |
| anemia of chronic disease | Low, as the body holds iron intracellularly with ferritin. | Low. The body produces less transferrin (but more ferritin), presumably to keep iron away from pathogens that require it for their metabolism. This is mainly regulated by increased hepcidin production. | Normal |
| pregnancy or use of hormonal contraception, but without iron deficiency | Normal | High. The liver increases the production of transferrin, thus raising TIBC. | Low, as there is excess transferrin with normal serum iron levels. |
Information About Total Iron Binding Capacity Test
How the Test is Performed
A blood sample is required.
How to Prepare for the Test
You should not eat or drink for 8 hours prior to the test.
Particular medicines might affect the outcome of this test. Your provider will tell you if you need to stop taking any medicines. DO NOT stop any medicine before speaking with your supplier.
Medicines that can affect the test result include:
- Adrenocorticotropic hormone (ACTH).
- Contraceptive pill.
- Chloramphenicol.
- Fluorides.
How the Test will Feel
When the needle is inserted to draw blood, some people feel moderate pain. Others feel just a prick or stinging. Afterward, there might be some throbbing or a slight contusion. This soon goes away.
Why the Test is Performed
Your company may recommend this test if:.
You have signs or symptoms of anemia due to low iron.
Other lab tests suggest you have anemia due to low iron levels.
TIBC Normal Ranges
Normal worth variety is:
- Iron: 60 to 170 micrograms per deciliter (mcg/dL) or 10.74 to 30.43 micronoles per liter (micromol/L).
- TIBC: 240 to 450 mcg/dL or 42.96 to 80.55 micromol/L.
- Transferrin saturation: 20% to 50%.
The numbers above are common measurements for outcomes of these tests. Normal value varieties might vary somewhat among various labs. Some labs use different measurements or test various samples. Speak to your provider about the meaning of your particular test outcomes.
What Abnormal Results Mean
TIBC is normally greater than normal when the body’s iron supplies are low. This can occur with:
- Iron shortage anemia.
- Pregnancy (late).
Lower-than-normal TIBC may suggest:
- Anemia due to red cell being ruined too quickly (hemolytic anemia).
- Lower-than-normal level of protein in the blood (hypoproteinemia).
- Inflammation.
- Liver disease, such as cirrhosis.
- Malnutrition.
- Decrease in red blood cells from the intestines not properly taking in vitamin B12 (pernicious anemia).
- Sickle cell anemia.
Risks during TIBC Test
There is very little risk included with having your blood taken. Veins and arteries differ in size from one person to another and from one side of the body to the other. Taking blood from some people may be harder than from others.
Other risks connected with having blood drawn are slight, however may include:
- Extreme bleeding.
- Passing out or feeling lightheaded.
- Hematoma (blood accumulation under the skin).
- Infection (a minor risk any time the skin is broken).
