Factor V Leiden Testing Guidelines

Indications for Testing

• Factor V Leiden testing is recommended specifically for patients with venous thromboembolism (VTE) where results may indicate risk of recurrence and influence anticoagulation treatment decisions, according to the International Society on Thrombosis and Haemostasis (ISTH) guidelines 1
• The International Society on Thrombosis and Haemostasis (ISTH) guidelines specify that thrombophilia evaluation, including Factor V Leiden testing, should be performed in the context of VTE evaluation, not for arterial or retinal vascular occlusions alone 2

Testing Pitfalls

• Do not order thrombophilia panels reflexively for all retinal vascular occlusions, as the yield is extremely low in patients with conventional risk factors and no history of systemic thrombosis, as recommended by the International Society on Thrombosis and Haemostasis (ISTH) guidelines 1, 2