Test result | Causes of test result pattern | |
PT | aPTT | |
Prolonged | Normal | Inherited |
Factor VII deficiency | ||
Acquired | ||
Mild vitamin K deficiency | ||
Liver disease | ||
Warfarin* | ||
Acute DIC¶ | ||
Normal | Prolonged | Inherited |
Deficiency of factor VIII, IX, or XI | ||
Deficiency of factor XII, prekallikrein, or HMW kininogen (not associated with a bleeding diathesis) | ||
von Willebrand disease (variable) | ||
Acquired | ||
Heparin, dabigatran, argatroban, direct factor Xa inhibitors (variable)* | ||
Acquired inhibitor of factor VIII, IX, XI, or XII | ||
Acquired von Willebrand syndrome | ||
Lupus anticoagulant (more likely to be associated with thrombosis than bleeding) | ||
Prolonged | Prolonged | Inherited |
Deficiency of prothrombin, fibrinogen, factor V, or factor X | ||
Combined factor deficiencies | ||
Acquired | ||
Liver disease | ||
Acute DIC¶ | ||
Severe vitamin K deficiency | ||
Anticoagulants (warfarin, direct thrombin inhibitors, others)* | ||
Acquired inhibitor of prothrombin, fibrinogen, factor V, or factor X | ||
Amyloidosis-associated factor X deficiency | ||
Anticoagulant rodenticide poisoning |
PT: prothrombin time; aPTT: activated partial thromboplastin time; DIC: disseminated intravascular coagulation; HMW: high molecular weight.
* In principle, many anticoagulants affect common pathway factors and can prolong both the PT and the aPTT if present at high enough levels. As examples:¶ In chronic DIC (also called compensated DIC) both the PT and aPTT may be normal.
Do you want to add Medilib to your home screen?