Which factor is the most common underlying cause of superficial thrombophlebitis?

The most common underlying cause of superficial thrombophlebitis is often associated with venous stasis, inflammation, and trauma rather than a specific hypercoagulable state. Factor V Leiden is a genetic mutation that increases the risk of venous thromboembolism by making clotting factor V resistant to inactivation by activated protein C. This can lead to an increased tendency for clot formation, which can contribute to both deep vein thrombosis and superficially located veins, particularly when there are other risk factors present.

Superficial thrombophlebitis generally presents with localized inflammation of a vein, which can occur due to injury, prolonged immobility, or as a complication of intravenous catheter placement. While the other options represent conditions that are linked to increased clotting risks, they are less commonly associated specifically with superficial thrombophlebitis compared to the more prevalent factors such as venous stasis or physical irritation leading to inflammation.

Therefore, while not a straightforward choice, recognizing that a mutation like Factor V Leiden can predispose individuals to venous thrombotic events, including superficial thrombophlebitis, reflects its relevance as an underlying cause in certain populations. This understanding helps in identifying additional risk factors beyond just the thrombosis itself