**Question:** A patient with positive antiphospholipid antibodies would have all the following EXCEPT

A. Increased risk of deep vein thrombosis (DVT)
B. Increased risk of stroke
C. Increased risk of pulmonary embolism
D. Increased risk of myocardial infarction

**Correct Answer:** D. Increased risk of myocardial infarction

**Core Concept:** Antiphospholipid antibodies (APAs) are a group of autoantibodies that bind to phospholipids or phospholipid-protein complexes, leading to a hypercoagulable state and increased risk of thrombosis. The presence of antiphospholipid antibodies is associated with a prothrombotic state due to various factors, including impaired fibrinolysis, platelet dysfunction, and endothelial cell activation.

**Why the Correct Answer is Right:** APAs are primarily linked to a hypercoagulable state, which increases the risk of venous thromboembolic events, such as deep vein thrombosis (DVT), pulmonary embolism, and arterial thrombosis. While these patients are at risk for thrombosis, myocardial infarction (MI) is not considered a direct consequence of antiphospholipid antibodies. Myocardial infarction is typically caused by atherosclerotic plaque rupture, leading to coronary artery occlusion, and is not directly related to the hypercoagulable state induced by antiphospholipid antibodies.

**Why Each Wrong Option is Incorrect:**

A. Increased risk of deep vein thrombosis (DVT): DVT is a venous thromboembolic event that occurs due to the hypercoagulable state induced by antiphospholipid antibodies. This option is correct as APAs are associated with an increased risk of DVT.

B. Increased risk of stroke: While antiphospholipid syndrome can increase the risk of thrombotic events, specifically ischemic stroke, it is not solely due to the presence of APAs. Other factors, such as arterial pathology (atherosclerosis) and vascular risk factors, also play a significant role in stroke pathogenesis.

C. Increased risk of pulmonary embolism: Similar to stroke, pulmonary embolism is primarily caused by the presence of deep vein thrombosis (DVT) in the lower limbs, which can lead to pulmonary embolism. This option is correct as APAs are associated with an increased risk of pulmonary embolism.

D. Increased risk of myocardial infarction (MI): As explained above, MI is caused by atherosclerosis, plaque rupture, and coronary artery occlusion, not directly related to the hypercoagulable state induced by antiphospholipid antibodies. This option is incorrect.

**Clinical Pearls:**

1. Antiphospholipid syndrome is a clinical entity characterized by the presence of antiphospholipid antibodies and thrombotic events. The syndrome is commonly associated with an increased risk of venous thromboembolic events, such as deep vein thrombosis (DVT), pulmonary embolism, and arterial thrombotic events like stroke and myocardial infarction (MI).
2. Although antiphospholipid antibodies can lead to a hypercoagulable state,