Procoagulable states

Question 1

How does factor V leiden cause a procoagulable state?

Answer 1

Activated factor V and activated 10a join to the form the prothrombinase complex that is required for activation of thrombin

Factor V leiden mutation leads to resistance to inactivation by activated protein C (APC) therefore increased propensity to clot

Question 2

How does protein C and S deficiency cause a procoagulable state?

Answer 2

Protein C and S are required to the form the activated protein C complex that inactivates factor V (and therefore the activation of thrombin)

Deficiency in either causes more active factor V therefore increase propensity to clot