Factor VII deficiency

Definition

Factor VII deficiency is a disorder that runs in families. It is caused by a lack of enough plasma protein factor VII and leads to abnormal blood clotting (coagulation).

Alternative Names

Causes

This disorder occurs when you lack factor VII, an important clotting protein.

When you bleed, the body launches a series of activities that help the blood clot. This is called the coagulation cascade. The process involves special proteins called coagulation factors. (Factor VII is a coagulation factor.) Each factor's reaction triggers the next reaction. The final product of the coagulation cascade is the blood clot.

When certain coagulation factors are missing, the chain reaction does not take place normally. In this disorder, bleeding can vary from mild to severe within the same person over time. Bleeding may begin during infancy or childhood. Gastrointestinal and central nervous system bleeding can occur.

The risk factor is a family history of bleeding. The incidence is 1 in 500,000.

References

Hoffman R, Benz E, Shattil S, Furie B, Cohen H. Hematology: Basic Principles and Practice. 4th ed. Philadelphia, Pa: Churchill Livingstone; 2004.

Levi M, Peters M, Büller HR. Efficacy and safety of recombinant factor VIIa for treatment of severe bleeding: A systematic review. Crit Care Med. April 2005;33:883-890.