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Factor V Leiden and activated protein C resistance

Kenneth A Bauer, MD
Section Editor
Lawrence LK Leung, MD
Deputy Editor
Jennifer S Tirnauer, MD


Factor V Leiden (FVL) is a mutant form of coagulation factor V. The FVL mutation renders factor V (both the activated and inactive forms) insensitive to the actions of activated protein C (aPC), a natural anticoagulant. As a result, individuals who inherit the FVL mutation are at increased risk of venous thromboembolism (VTE). However, FVL is extremely common in the population, and many individuals with the mutation will never have a VTE. For these reasons, VTE risk reduction (both primary prevention and prevention of recurrence) may involve some challenging decisions.

This topic review discusses the diagnosis of FVL and the management of individuals who carry this mutation.

Separate topic reviews discuss other thrombophilias and the role of thrombophilia screening in various populations:

Other thrombophilias:

Prothrombin G20210A mutation – (See "Prothrombin G20210A mutation".)

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Literature review current through: Sep 2017. | This topic last updated: Oct 03, 2017.
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