The APTT blood test is used to determine what the Activated Partial Thromboplastin Time happens to be for a patient. This is a measurement of how effective and timely the blood’s clotting process happens to be. It is typically ordered as a first option blood test when a patient presents with unexplained or uncontrolled bleeding so hemostasis can be properly evaluated.
Unlike other blood tests that measure clotting, the APTT blood test is able to evaluate multiple clotting factors at once. It may also be ordered with a PT blood test and a fibrinogen blood test for a complete look at all clotting factors to determine what may be causing the excessive, uncontrolled, or inappropriate bleeding.
The APTT blood test cannot offer a medical provider with a specific diagnosis with its result. It can, however, indicate that a patient needs further testing to determine what may be affecting their health.
When To Ask About the APTT Blood Test
The APTT blood test is typically ordered when there is a bleeding issue which needs to be examined. This means bleeding that is unexplained, such as an unusual bruise which keeps getting larger, or uncontrolled because it won’t stop may result in having this test ordered. If an individual is experiencing what may be a blood clot somewhere, this test may also be ordered.
Certain chronic conditions may also benefit from having the APTT blood test ordered. Certain liver conditions may affect a person’s hemostasis and this test can help a medical provider begin to identify and/or treat that condition. It may also be ordered if there is a suspicion that a patient may be suffering from lupus.
Certain surgical treatments may also require the APTT blood test to monitor health before and after the treatment.
What Do My APTT Blood Test Results Mean?
Because clotting functions are being measured with the APTT blood test, the results given by a laboratory are typically given in time intervals. Normal results are based on the way each laboratory measures the clotting factors. Healthy individuals may have mild to moderate clotting deficiencies on one more more factors and still have results that are interpreted as being normal.
When there are prolonged APTT test results, then this is typically the result of an inherited factor deficiency. In this instance, the most common bleeding disorder would be von Willebrand disease. Certain types of hemophilia may also cause this test result, as will specific deficiencies on individualized clotting factors that may or may not be medically significant.
Acquired deficiencies, such as a lack of Vitamin K, can also cause prolonged APTT results. Certain antibiotics have also been known to cause a prolonged APTT result if they are taken for a long period of time.
If the APTT blood test results are shortened, then the most common reason would be because a patient has two or more circulating procoagulants that are affecting the test results. This condition is called DIC, or Disseminated Intravascular Coagulation. Certain cancers, when they become extensive, may also shorten clotting. Tissue inflammation or damage that is present when the test is being performed may also cause the results to shorten more than they normally would if that damage or inflammation was not present.
Here’s What You Need To Know
Your medical provider may ask you to stop taking certain medications for up to 2 weeks or more before the APTT blood test will be ordered. Antihistamines and aspirin can affect test results. People who take large amounts of Vitamin C as a supplement may also be asked to refrain from doing so until after the blood test.
Heparin contamination is a common problem that affects test results as well. Heparin is used for IV lines to keep the line open. It will also affect the clotting timing if the blood sample is taken from an IV tube instead of directly from a vein.
The APTT blood test is not typically used for screening purposes. It may, however, be used for screening in individuals who have a family history of bleeding or clotting issues. This is especially true for individuals who may need surgery and have this family history so the medical provider can determine the extent of a person’s risk.
APTT results are not something that can be changed unless they are caused because of a Vitamin K deficiency. It is used to measure the effectiveness of the body’s clotting system. If you are experiencing the signs and symptoms that are mentioned here in this guide, then speak with your medical provider about the APTT blood test. It could be the first step needed to develop a treatment plan to improve your health.