|Back to Main Print This Page Email to a Friend|
The haptoglobin blood test measures the level of haptoglobin in your blood.
Haptoglobin is a protein produced by the liver. It attaches to a certain type of hemoglobin in the blood.
A blood sample is needed.
Certain medicines may affect the results of this test. Your doctor will tell you if you need to stop taking any medicines. Do not stop any medicine before talking to your doctor.
Drugs that can raise haptoglobin levels include:
Drugs that can lower haptoglobin levels include:
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.
This test is done to see how fast your red blood cells are destroyed. When red blood cells die, they release hemoglobin.
Haptoglobin attaches to this released hemoglobin, which is also called "free" hemoglobin. Free hemoglobin is not contained within red blood cells. The level of free hemoglobin is usually very low. But it rises when red blood cells are dying.
When the haptoglobin and hemoglobin attach, the new molecule goes to the liver. There, parts of it (such as iron and amino acids) are recycled. The haptoglobin is destroyed.
When red blood cells are actively being destroyed, haptoglobin disappears faster than it is created. Thus, the levels of haptoglobin in the blood drop.
The normal range is 41 - 165 mg/dL (milligrams per deciliter).
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the meaning of your specific test results.
Higher-than-normal levels may be due to:
Lower-than-normal levels may be due to:
There is very little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
Schwartz RS. Autoimmune and intravascular hemolytic anemias In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, Pa: Elsevier Saunders; 2011:chap 163.
Sheehan AM, Yee DL. Resources for the hematologist: interpretive comments and selected reference values for neonatal, pediatric, and adult populations. In: Hoffman R, Benz EJ Jr, Silberstein LE, et al., eds. Hematology: Basic Principles and Practice. 6th ed. Philadelphia, Pa: Elsevier Saunders; 2012:chap 164.