APTT Test (Activated Partial Thromboplastin Time)

APTT test measured to investigate a bleeding or thrombotic episode. It helps evaluate the risk of excessive bleeding prior to a surgical procedure. Also, to monitor heparin anticoagulant therapy.

Your health practitioner may recommend aptt test for you if you show symptoms of prolonged and excessive bleeding which includes:

• Frequent nosebleeds
• Blood in urine
• Heavy menstruation for women
• Painful and swollen joints
• Easy bruising

The activated partial thromboplastin time is a functional measure of the intrinsic and usual pathways of the clotting cascade. To form blood clots, to seal off injuries, to blood vessels and tissue, to restrict further blood loss, and to give the damaged areas time to seal the body using the coagulation cascade. The cascade contains a group of clotting factors. These proteins are activated serially along either the extrinsic or intrinsic pathways.

The branches then come together into the common pathway, and complete their task with the formation of a steady blood clot. These three pathways have to work when a person starts bleeding. Each component of the coagulation cascade must be working properly and be present in enough quantity for normal blood formation. Stable clot formation will be inhibited and excessive bleeding and/or clotting may occur if there is an inherited or assimilated deficiency in one or more of the factors, or if the factors are functioning unusually. The aptt test measures the amount of time that it takes for clotting to happen when reagents are added to plasma in a test tube.

The test is required in cases of : 
- Suspected problems with 1 or more clotting factors. 
-Bleeding disorders, such as von Willebrand disease or another disease that prevents your blood from clotting.
-To monitor people who are getting heparin therapy. Heparin is a blood thinner used to prevent dangerous blood clots. 

The test calculates the APTT in the blood. 

The test requires a blood sample. A tourniquet (elastic) band is placed tightly on the upper arm. The patient is then asked to make a fist. This helps in the build-up of blood filling the veins. The skin is disinfected before needle insertion and the blood sample is collected in vacutainer. 

Prolonged APTT tests may be due to inherited or acquired factor deficiencies,  lupus anticoagulant (LA), DIC, fibrinolysis, cirrhosis, malabsorption, and liver diseases. APTT levels may also be affected in patients on anti-coagulant therapy. 
 

The Activated Partial Thromboplastin Time (APTT) test is a blood coagulation test that measures the time it takes for blood to clot after adding specific reagents. It evaluates the intrinsic and common final pathways of the coagulation cascade, helping to assess the functioning of various clotting factors.

The APTT test is recommended in cases of suspected bleeding disorders, monitoring the heparin therapy, unexplained bleeding or clotting, evaluating chronic conditions affecting coagulation, autoimmune diseases like lupus or antiphospholipid syndrome, and for preoperative and postoperative monitoring. 

The APTT test is essential because it helps diagnose and monitor conditions related to blood clotting, ensures proper dosing of heparin, and aids in identifying underlying causes of bleeding or clotting disorders. It provides critical information for managing patients with coagulation issues.

Anyone suspected of having a bleeding disorder, those on heparin therapy, individuals with unexplained bleeding or clotting, and those with chronic conditions affecting coagulation are eligible for the APTT test. Additionally, pregnant women experiencing recurrent miscarriages may be tested to rule out antiphospholipid syndrome.

The benefits of the APTT test include diagnosing and monitoring bleeding disorders, adjusting heparin dosages to prevent dangerous clots, identifying underlying causes of unexplained bleeding or clotting, monitoring chronic conditions, assessing coagulation status preoperatively and postoperatively, and detecting autoimmune conditions like lupus anticoagulant.

Fasting is not required before taking the APTT test. However, it is important to inform your healthcare provider about all medications, herbs, vitamins, or supplements you are currently taking, as some of these may influence the test results. 

A prolonged APTT indicates that clotting is taking longer than normal, which could be due to deficiencies in one or more clotting factors, the presence of inhibitors such as lupus anticoagulant, or other conditions affecting clotting. Further tests are usually conducted to determine the specific cause.

A normal APTT range is typically between 21 and 35 seconds, although this can vary slightly depending on the laboratory and the specific method used.

Yes, many labs, including Metropolis Healthcare, offer home sample collection for the APTT test. This convenient option allows you have your blood samples collected by a trained professional in the comfort of your home, making it safe and easy. 

The results of the APTT test are typically available after 4 hours, depending on when the sample is collected and processed.