Factor X Activity

Optimal result: 76 – 183 %

Factor X levels are increased in pregnancy and in association with oral contraceptives. Defects in protein Z lead to increased factor Xa activity, which increases the risk for thrombosis.

Decreased factor X activity may be related to:

- Amyloidosis (a rare disease that occurs when an abnormal protein, called amyloid, builds up in your organs and interferes with their normal function.)

- Deficiency of factor X that is present at birth (= congenital)

- Disseminated intravascular coagulation (DIC) -- a condition in which blood clots form throughout the body, blocking small blood vessels.

- Fat malabsorption

- Heparin use (blood thinner)

- Liver disease

- Vitamin K deficiency

- Warfarin (Coumadin) use (blood thinner or anticoagulant)

The factor X assay is a blood test to measure the activity of factor X -- one of the substances involved in blood clotting (coagulation).

Factor X is a clotting protein (also called a clotting factor). Clotting factors are specialized proteins that are essential for proper clotting, the process by which blood clumps together to plug the site of a wound to stop bleeding. Clotting requires a series of reactions to ultimately form a clot to plug a wound. This is referred to as the clotting (coagulation) cascade. The clotting cascade involves different substances in addition to clotting factors. Factor X, which is produced (synthesized) in the liver, eventually interacts with other clotting factors and certain cells or substances, e.g. platelets or fibrinogen, to help to form a clot. Factor X deficiency is caused by a variation (mutation) in the F10 gene. 

Factor X Activity
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