Factor X deficiency
Factor X (ten) deficiency is a disorder caused by too little of a protein called factor X in the blood. It leads to problems with normal blood clotting (coagulation).
When you bleed, your body starts a series of reactions that help the blood clot. This is called the coagulation cascade. The process involves special proteins called coagulation factors. You can have a higher chance of excess bleeding when one or more of these clotting factors are missing.
Factor X deficiency is often caused by a defect in the factor X gene that is passed through families. This is called inherited factor X deficiency. Bleeding ranges from mild to severe depending on the extent of deficiency
Factor X deficiency may also develop due to another condition or use of medications. This is called “acquired factor X deficiency.” Acquired factor X deficiency is common. It may be caused by:
- Lack of vitamin K (some newborns are born with vitamin K deficiency), systemic amyloidosis, severe liver disease
- Use of medicines that prevent clotting (anticoagulants such as warfarin or Coumadin)
Women with factor X deficiency may first be diagnosed when they have very heavy menstrual bleeding and bleeding after childbirth. The condition may be first noticed in newborn boys if they have bleeding that lasts longer than normal after circumcision.
Inherited factor X deficiency affects 1 out of every 500,000 people.
Exams and Tests
- Low factor X activity
- Normal thrombin time
- Prolonged partial thromboplastin time (PTT)
- Prolonged prothrombin time (PT)
You can control blood loss by getting infusions of fresh or frozen plasma or concentrates of clotting factors into the blood. If you lack vitamin K, you can take vitamin K by mouth, through injections under the skin, or through a vein (intravenously).
Knowing that you have a bleeding disorder helps the doctor can take extra care if you need surgery. It also lets you alert also tell other family members who may have the same problem.
You can ease the stress of illness by joining a support group where members share common experiences and problems.
The outcome is most often good if the condition is mild or you get treatment.
Inherited factor X deficiency is a life-long condition.
The outlook for acquired factor X deficiency depends on the cause. If it is caused by liver disease, the outcome depends on how well your liver disease can be treated. Taking vitamin K supplements will treat vitamin K deficiency. If the disorder is caused by amyloidosis, there are several treatment options, including surgery to remove your spleen.
Severe bleeding or sudden loss of blood (hemorrhage) can occur. The joints may get deformed in severe disease from many bleeds.
When to Contact a Medical Professional
Get emergency medical help if you have an unexplained or severe loss of blood.
Inherited factor X deficiency is rare. There is no known prevention.
In: Hoffman R, Benz EJ Jr., Shattil SJ, et al, eds. Hoffman Hematology: Basic Principles and Practice. 5th ed. Philadelphia, PA: Churchill Livingstone Elsevier; 2008:chap 127.
Gailani D, Neff AT. Rare coagulation factor deficiencies In: Hoffman R, Benz EJ Jr, Silberstein LE, Heslop HE, Weitz JI, eds. Hematology: Basic Principles and Practice. 6th ed. Philadelphia, PA: Saunders Elsevier; 2012:chap 139.
Ragni MV. In: Hemorrhagic disorders: Coagulation factor deficiencies. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 177.
Reviewed By: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, Stephanie Slon, and Nissi Wang