The Haptoglobin test contains 1 test with 1 biomarker.
Brief Description: The Haptoglobin test measures levels of Haptoglobin, a protein deployed by the liver to remove hemoglobin that is free or unbound in the blood.
Also Known As: HPT Test, Hemoglobin-binding Protein Test, Hp Test
Collection Method: Blood Draw
Specimen Type: Serum
Test Preparation: Overnight fasting is preferred
Average Processing Time: 2 to 3 days
When is a Haptoglobin test ordered?
When someone exhibits symptoms and/or indicators of hemolytic anemia, a haptoglobin test is prescribed. Several symptoms and indicators include:
- drowsiness, weakness
- Pale skin Growing weak
- breathing difficulty
- a quick heartbeat
- brown or red urine
The results of further laboratory tests that are consistent with hemolytic anemia may also warrant testing. These could exhibit elevated bilirubin levels, urine hemoglobin, a decrease in RBC count, an increase in reticulocyte count, and elevated lactate dehydrogenase values.
What does a Haptoglobin blood test check for?
The body employs the protein haptoglobin, which is made by the liver, to remove free hemoglobin from circulation. The amount of haptoglobin in the blood is determined by this test.
The protein complex called hemoglobin, which contains iron, carries oxygen throughout the body. It rarely circulates freely in the blood and is typically present inside red blood cells. In the blood, haptoglobin binds to free hemoglobin. A haptoglobin-hemoglobin complex is created, which is quickly removed from circulation for haptoglobin breakdown and iron recycling.
However, as more RBCs sustain injury or fragmentation, more hemoglobin is released into the blood, increasing the amount of free hemoglobin in circulation. Haptoglobin levels in the blood will temporarily drop when a significant amount of RBCs are destroyed because haptoglobin is eaten up more quickly than the liver can generate it. A disorder that causes red blood cells to be damaged or break apart may be indicated by a reduction in haptoglobin levels. The level of free hemoglobin in the blood increases when haptoglobin's binding capacity is surpassed, which may result in tissue damage and organ failure.
Conditions that are inherited or acquired may increase RBC oxidation. Examples include transfusion reactions, specific medications, and mechanical failure, which can occur with some artificial heart valves. Hemolytic anemia can result from the destruction, which can be minor or severe, rapid or gradual, and mild or long-lasting. People who have hemolytic anemia may exhibit symptoms like weakness, exhaustion, and shortness of breath, as well as pale or jaundiced skin.
As liver impairment may prevent both the formation of haptoglobin and the clearance of the haptoglobin-free hemoglobin complexes, liver disease may also cause decreased haptoglobin concentrations.
Lab tests often ordered with a Haptoglobin test:
- Complete Blood Count (CBC)
- Reticulocyte Count
- Blood Smear
- Direct Antiglobulin Test
Conditions where a Haptoglobin test is recommended:
- Hemolytic Anemia
- Liver Disease
How does my health care provider use a Haptoglobin test?
Testing for hemoglobin is primarily used to identify and assess hemolytic anemia and to differentiate it from anemia caused by other conditions. Testing is done to evaluate whether red blood cells are disintegrating or perishing too soon. The complete blood count, reticulocyte count, lactate dehydrogenase, bilirubin, direct antiglobulin test, and blood smear are a few examples of the lab tests that can be utilized in conjunction with it.
A rare cause of anemia is hemolytic anemia. The disorder may be hereditary or may appear over a person's lifetime as a result of a variety of events. It may appear quickly or may take time to appear.
Despite being a sensitive test for hemolytic anemia, the haptoglobin test cannot be used to determine what is causing the illness. Other laboratory tests, such as autoantibody tests to identify autoimmune reasons, sickle cell tests, G6PD tests, or a hemoglobin evaluation, can be required to help identify the cause.
If a person has undergone blood transfusions, a haptoglobin test may be requested in addition to a direct antiglobulin test to assist identify whether they experienced a transfusion reaction.
Testing may be performed later to assess concentration changes and help identify whether the accelerated destruction of RBCs is still happening or has stopped if haptoglobin levels are low.
What do my Haptoglobin test results mean?
Results from additional tests, such as a reticulocyte count, red blood cell count, hemoglobin, hematocrit, or complete blood count, are also analyzed carefully.
A person is likely to have some degree of hemolytic anemia, in which red blood cells are destroyed in the circulation, if their haptoglobin level is noticeably low, along with an elevated reticulocyte count, a decreased RBC count, hemoglobin, and hematocrit.
RBC destruction is probably happening in organs like the spleen and liver if the haptoglobin is normal or borderline normal and the reticulocyte count is elevated. The haptoglobin is not consumed since the liberated hemoglobin is not released into the blood, hence its level is normal. Haptoglobin levels, however, may be low in severe extravascular hemolysis because excess hemolysis might release some free hemoglobin into the bloodstream.
It is likely that the anemia seen is not caused by RBC breakdown if the haptoglobin level is normal and the reticulocyte count is not elevated.
We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.