Differential diagnoses associated with coagulation assay results
Prolonged prothrombin time (PT), normal activated partial thromboplastin time (aPTT) |
Factor VII deficiency or factor VII inhibitor |
Liver disease |
Vitamin K deficiency |
Warfarin use |
Disseminated intravascular coagulation |
Normal PT, prolonged aPTT |
Deficiency of intrinsic pathway factors (VIII, IX, XI, XII) or inhibitors of these clotting factors |
von Willebrand disease (if factor VIII is very low) Heparin use |
Lupus anticoagulant (usually associated with thrombosis instead of bleeding) |
Prolonged PT and aPTT |
Deficiency of common pathway factors (II, V, X, or fibrinogen) |
Severe liver disease |
Vitamin K deficiency |
Warfarin use |
Disseminated intravascular coagulation |
Heparin overdose |
Normal PT and aPTT with bleeding |
Platelet dysfunction (acquired or congenital) |
von Willebrand disease (if factor VIII is mildly decreased) |
Scurvy |
Ehlers-Danlos syndrome |
Hereditary hemorrhagic telangiectasia |
Factor XIII deficiency |
Hyperfibrinolysis |