When coagulation screening tests are performed to verify normal function of the coagulation system (eg, preoperative, routine examination), they sometimes indicate an abnormality that may be unexplained (ie, prolonged clotting times).
Possible causes of a prolonged clotting time include:
- Coagulation factor deficiency(ies), congenital or acquired
- Coagulation factor inhibitor Specific coagulation factor inhibitor
- Nonspecific inhibitor (lupus-like anticoagulant)
- Drugs (eg, heparin or direct thrombin inhibitor present in specimen
- Profile Tests
- Diagnostic and Screening Tests