Factor VII deficiency

Alternative names:

extrinsic factor deficiency

Definition:

An inherited disorder that causes abnormal blood clotting (coagulation), resulting from a deficiency of the plasma protein Factor VII.

Causes, incidence, and risk factors:

Normal blood coagulation is a complex process involving as many as 20 different plasma proteins, which are known as blood coagulation factors. A series of complex chemical reactions using these factors takes place very rapidly to form an insoluble protein called fibrin that stops bleeding. When certain coagulation factors are deficient or 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. A history of bleeding may occur in infancy or childhood. Gastrointestinal and central nervous system bleeding can occur.