Haptoglobin
Haptoglobin
Does this test have other names?
HPT, hemoglobin-binding protein, Hp
What is this test?
This test measures the level of a protein called haptoglobin in your blood.
Haptoglobin is made by your liver. It binds to a type of hemoglobin that's made when red blood cells die, leading to anemia. This haptoglobin-hemoglobin complex is removed from your body by your liver. If too much hemoglobin is bound to haptoglobin, the levels of haptoglobin will drop. The level of haptoglobin in your blood helps your healthcare provider figure out what type of anemia you have.
Why do I need this test?
You may have this test if your healthcare provider suspects that you have anemia, or a low number of red blood cells. Symptoms of anemia include:
Weakness
Tiredness
Pale skin
Shortness of breath
Jaundice, or a yellow tinge to your skin and the whites of your eyes
Dark-colored urine
You may also have this test if you have symptoms of liver disease.
What other tests might I have along with this test?
Your healthcare provider may also order other blood tests, including:
Reticulocyte count
Blood smear
Hemoglobin
Hematocrit
Your healthcare provider may also order a direct antiglobulin test if you have had a blood transfusion and he or she suspects that you are reacting to the transfusion. Your healthcare provider may also order an indirect bilirubin test.
What do my test results mean?
Test results may vary depending on your age, gender, health history, the method used for the test, and other things. Your test results may not mean you have a problem. Ask your healthcare provider what your test results mean for you.
Results are given in milligrams per deciliter (mg/dL). Normal results depend on your age and gender, other diseases or conditions you have, and the method the lab uses to analyze the test.
For adults, a normal value is 50 to 220 mg/dL.
If your levels are lower, it means you may have hemolytic anemia, in which your red blood cells are prematurely destroyed. Lower levels may also mean that you have a reaction to a blood transfusion, or that you have liver disease or infectious mononucleosis.
Levels that are higher than normal may mean that you:
Have acute rheumatic disease
Have had a heart attack
Have ulcerative colitis
Have an ongoing infection
Take androgens, a type of hormone
How is this test done?
The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand.
Does this test pose any risks?
Having a blood test with a needle carries some risks. These include bleeding, infection, bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may feel a slight sting or pain. Afterward, the site may be sore.
What might affect my test results?
Certain medicines can affect your results.
How do I get ready for this test?
You don't need to prepare for this test. Be sure your healthcare provider knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use.
Updated:  
September 30, 2017
Sources:  
Approach to diagnosis of hemolytic anemia in the adult. UpToDate., Haptoglobin (serum). Ferri, FF. Ferri's Clinical Advisor. 2012;1., McPherson. Henry's Clinical Diagnosis and Management by Laboratory Methods. 2017, 23rd ed., pp. 573-74.
Reviewed By:  
Fraser, Marianne, MSN, RN,Haldeman-Englert, Chad, MD