HomeLab TestsHaptoglobin (HP) Test
Back to Lab Tests
Haptoglobin (HP) Test
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Lab Tests

Haptoglobin (HP) Test

A haptoglobin test measures the amount of haptoglobin in your blood to help diagnose conditions like hemolytic anemia, where red blood cells are destroyed faster than they can be replaced.

Overview

The haptoglobin (HP) test measures the amount of haptoglobin in your blood. Haptoglobin is a protein produced by the liver that helps remove hemoglobin from the bloodstream when it is found outside of red blood cells.

Hemoglobin is a protein within red blood cells responsible for carrying oxygen from the lungs to the rest of the body. While most hemoglobin remains inside red blood cells, small amounts circulate in the bloodstream when cells die or are damaged. Haptoglobin binds to this free hemoglobin, allowing the liver to remove it from the body.

If red blood cells are damaged or break down faster than usual, excess hemoglobin enters the bloodstream. Haptoglobin binds to this extra hemoglobin to clear it, which can deplete haptoglobin levels faster than the liver can produce it. Low haptoglobin levels may indicate a red blood cell disorder, such as anemia.

Other names: hemoglobin-binding protein, HPT, Hp

Purpose and Indications

The haptoglobin test is primarily used to diagnose hemolytic anemia, a disorder where red blood cells are destroyed faster than they can be replaced. It may also be used to determine if other types of anemia or blood disorders are causing specific symptoms.

You may need this test if you experience symptoms of hemolytic anemia or another blood disorder, including:

  • Weakness or fatigue
  • Pale skin
  • Shortness of breath
  • Headache
  • Dizziness
  • Arrhythmia (a problem with the rate or rhythm of your heartbeat)
  • Jaundice (a condition that causes skin and eyes to turn yellow)
  • Dark colored urine

This test may also be required following a blood transfusion. It is often performed alongside a direct anti-globulin test to check for adverse reactions to the transfusion.

Procedure and Preparation

What to Expect

A health care professional will collect a blood sample from a vein in your arm using a small needle. The blood is collected into a test tube or vial. You may feel a slight sting when the needle is inserted or removed. The procedure typically takes less than five minutes.

Preparation

No special preparations are required for a haptoglobin test.

Risks

Risks associated with this blood test are minimal. You may experience slight pain or bruising at the injection site, but these symptoms usually resolve quickly.

Understanding the Results

Low haptoglobin levels are considered normal for infants less than six months old. For other individuals, abnormal results may indicate various conditions:

Lower Than Normal Levels

A haptoglobin level that is lower than normal may be a sign of:

  • Hemolytic anemia
  • Liver disease
  • Reaction to a transfusion

Higher Than Normal Levels

A haptoglobin level that is higher than normal may be a sign of:

  • Ulcerative colitis
  • Acute rheumatic disease (such as arthritis or other conditions affecting joints, bones, and muscles)
  • A severe infection
  • Diabetes

Diagnosis and Management

To make a definitive diagnosis, your provider may order additional blood tests, which can be performed at the same time as or after the haptoglobin test. These may include:

  • Reticulocyte Count
  • Hemoglobin Test
  • Hematocrit Test
  • Lactate Dehydrogenase Test
  • Blood Smear
  • Complete Blood Count

Your provider will interpret your results by considering your symptoms, medical history, and the outcomes of other tests. It is important to inform your provider of any medications you are taking, as some medicines can cause haptoglobin test results to appear higher or lower than normal.

Additional Considerations

High haptoglobin levels can be a sign of an inflammatory disease, which involves disorders of the immune system. However, haptoglobin testing is not typically used to diagnose or monitor conditions associated with high haptoglobin levels. Additionally, severe blood loss and conditions that worsen kidney function may affect haptoglobin level results.

Frequently Asked Questions

Fasting is generally not required for a standard haptoglobin test. However, because this test is often ordered alongside other blood work such as a complete blood count (CBC) or liver function tests, your healthcare provider may ask you to fast for 8 to 12 hours beforehand. Always follow the specific instructions given by your lab or doctor, as individual protocols can vary.
The haptoglobin test is crucial for differentiating hemolytic anemia from other forms of anemia. In hemolytic anemia, where red blood cells are destroyed, haptoglobin levels are typically very low or undetectable because the protein is consumed binding to free hemoglobin. In contrast, in iron deficiency anemia or anemia of chronic disease, haptoglobin levels are usually normal or even elevated. This distinction helps guide further diagnostic testing and treatment strategies.
Certain medications can influence haptoglobin levels. For example, oral contraceptives and corticosteroids may cause mild elevations in haptoglobin. Some chemotherapy agents or drugs that cause liver stress might also alter levels. While rare, it is important to inform your healthcare provider of all medications, supplements, and herbal products you are taking before the test to ensure accurate interpretation of the results.
High haptoglobin levels are often associated with acute inflammation or infection, as haptoglobin is an acute-phase reactant produced by the liver in response to stress. Conditions such as rheumatoid arthritis, inflammatory bowel disease, or recent surgery can elevate levels. Additionally, high levels may be seen in certain cancers, particularly lung or breast cancer, and in conditions involving tissue damage or necrosis. It is important to interpret these results in the context of other clinical findings and symptoms.
Source: MedlinePlus, National Library of Medicine

MedlinePlus brings together authoritative health information from the National Library of Medicine (NLM), the National Institutes of Health (NIH), and other government agencies and health-related organizations.

kontakt@hittavard.se

Ⓒ 2024. Alla rättigheter förbehålls av juxt ab

Sök
Om ossVillkor och policyVanliga frågorKontakta oss