What is factor V deficiency?

Updated: Oct 06, 2020
  • Author: Irene S Pakos, DO; Chief Editor: Perumal Thiagarajan, MD  more...
  • Print


Factor V has both procoagulant and anticoagulant properties. Activated factor V stimulates the formation of thrombin, whereas anticoagulant factor V acts as a cofactor for aPC in the degradation of factor VIII/VIIIa, thereby reducing thrombin formation.

An inherited autosomal recessive deficiency of factor V proaccelerin (or accelerator globulin or labile factor) leads to a rare hemorrhagic tendency known as Owren disease or parahemophilia. The severity of the condition varies from bruising to lethal hemorrhage [106, 107, 108] Both PT and aPTT may be prolonged.

Lak et al identified epistaxis and excessive bleeding after surgery as the most common symptoms in 35 Iranian patients with an inherited factor V deficiency, with plasma levels of 1-10%. [109] More severe symptoms, such as gastrointestinal and central nervous system bleeding, were rare. The severity of bleeding symptoms was only partially related to the degree of factor V deficiency in plasma. Acquired inhibitors of factor V are rare causes of clinical bleeding, with severity ranging from mild to life threatening.

No factor V concentrate is available yet. Fu et al were successful using a combination of factor replacement, chemotherapy, and plasmapheresis in a patient with spontaneous, life-threatening intracranial bleeding caused by a factor V inhibitor. The patient deteriorated after initial treatment with fresh frozen plasma and platelet transfusions. He was subsequently treated with a combination of plasma exchange and chemotherapy, which led to complete recovery. Ref85}

Combined deficiency of coagulation factor V and factor VIII is an autosomal recessive disorder observed in a number of populations around the world. However, this disease appears to be most common in the Mediterranean basin, particularly in Jews of Sephardic and Middle Eastern origin living in Israel. [112]

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!