Activated Partial Thromboplastin Time (APTT) Test
- Category
- Blood Clotting
- Sample
- Blood sample taken from a vein in your arm
- Reports () Terms & Conditions Report time varies with time of sample collection.
- In 2 days
- Fasting
- No Fasting
- Age
- 5+ Years
APTT measures how long your plasma takes to clot through the 'intrinsic' clotting pathway.
Screens for bleeding disorders such as haemophilia and von Willebrand disease, monitors heparin therapy and is part of pre-surgery checks.
Easy bruising or bleeding, heavy periods, blood clots, before surgery, or people taking blood thinners.
No fasting needed.
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It can be due to clotting factor deficiency, heparin, liver disease or lupus anticoagulant. Further tests help find the cause.
No fasting is needed. You can eat and drink normally unless your doctor has advised otherwise.
Blood sample taken from a vein in your arm.
Usually within 11–35 hours after the sample reaches the lab. You will receive the report online.