Factor V Leiden

Definition

Factor V Leiden is a genetic mutation that increases the risk of developing abnormal blood clots in veins. It is a common hereditary disorder related to clotting and coagulation.

5 Must Know Facts For Your Next Test

1. Factor V Leiden mutation makes Factor V resistant to inactivation by activated protein C (APC), leading to increased thrombosis risk.
2. It is the most common inherited form of thrombophilia, affecting approximately 5% of the Caucasian population.
3. Individuals with one copy of the mutation (heterozygous) have a 4-8 times higher risk of venous thromboembolism (VTE); those with two copies (homozygous) have an even higher risk.
4. Diagnosis often involves genetic testing for the specific mutation or functional assays for APC resistance.
5. Management may include anticoagulant therapy, especially during high-risk situations such as surgery, pregnancy, or prolonged immobilization.

Review Questions

• What is the primary mechanism by which Factor V Leiden increases thrombosis risk?
• How does being heterozygous for Factor V Leiden affect one's risk of venous thromboembolism compared to someone who is homozygous?
• What are common methods used to diagnose Factor V Leiden?

Related terms

Anticoagulant Therapy: Medication regimen used to prevent blood clots from forming or growing.

Venous Thromboembolism (VTE): A condition in which a blood clot forms in a vein, typically in the legs or lungs.

Activated Protein C Resistance: A condition where protein C's ability to regulate blood clot formation is impaired, often due to Factor V Leiden mutation.