Coagulopathy

Question 1

Differential for prolonged PT-INR, normal PTT

Answer 1

1) **factor VII deficiency (think about clotting cascade)
2) liver disease
3) warfarin
4) mild vitamin K deficiency
5) **Anticoagulants – VKAs, NOACs, direct thrombin inhibitor

Question 2

Differential for normal PT + prolonged PTT

Answer 2

1) **factor deficiency (think about clotting cascade) – 8,9,11
2) vWF (variable)
3) lupus anticoagulant (more likely to be associated with thrombosis than bleeding)
4) **treatment with heparin, direct thrombin inhibitors, or Xa inhibitors (variable)

Question 3

Differential for prolongation of both PT and PTT

Answer 3

1) common pathway defects (Factor V or X deficiency)
2) Liver disease
3) DIC
4) severe vitamin K deficiency

Question 4

How degree of “correction” in mixing study is reported

Answer 4

1) Immediately

2) After incubation

Question 5

Coagulation studies in Factor XIII deficiency

Answer 5

Normal PTT and normal PT

Question 6

What is bethesda assay?

Answer 6

Assay for measuring Factor VIII inhibitor