Table of Contents
- Overview
- Results
- Risks
- Prevention
APTT; PTT; Activated partial thromboplastin time
Normal Values
The normal value will vary between laboratories. In general, clotting should occur between 25 to 35 seconds. If the person is taking blood thinners, clotting takes up to two and a half times longer.
Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
What abnormal results mean
An abnormal (too long) PTT result may be due to:
Disseminated intravascular coagulation (DIC) -
Factor XII or Factor XI deficiency Hemophilia A Hemophilia B Hypofibrinogenemia - Liver disease
- Lupus anticoagulants
Malabsorption - Vitamin K deficiency
Von Willebrand's disease
Previous Section
Review Date: 02/13/2011
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of
General Medicine, Department of Medicine, University of Washington
School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical
Director, A.D.A.M., Inc.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)
