What is the cause of thromboembolic disease associated with protein-losing enteropathy (PLE)?

• A. Antithrombin III
• B. Protein C deficiency
• C. Factor V Leiden mutation
• D. Vitamin K deficiency

Answer: (A)

Protein-losing enteropathy causes loss of proteins through the gut, including natural anticoagulants like antithrombin III. Antithrombin III normally inhibits thrombin and factor Xa; when it is depleted from the circulation, there is less restraint on coagulation, leading to a hypercoagulable state and a higher risk of thromboembolic events. This explains why thromboembolism is associated with PLE. Other options relate to different mechanisms: vitamin K deficiency tends to cause bleeding rather than clotting, and while genetic or other acquired coagulation abnormalities (like Factor V Leiden or protein C deficiency) can promote thrombosis, they are not the characteristic cause of thrombosis specifically associated with PLE.