Definition of Factor V deficiency:

Factor V deficiency is an inherited condition that affects the ability of the blood to clot.

Causes, incidence, and risk factors:

Normal blood coagulation is a complex process involving as many as 20 different proteins in blood plasma, which are known as blood coagulation factors. A series of complex chemical reactions using these factors takes place very rapidly to form a protein called fibrin, which stops bleeding.

Factor V deficiency is caused by a lack of the plasma protein Factor V. When certain coagulation factors are low or missing, the chain reaction does not take place normally. Factor V is rare, and can be caused by inheriting a defective Factor V gene or by acquiring an antibody that interferes with normal Factor V function.

You can acquire an inhibitor of Factor V:

• After giving birth
• After being treated with a certain type of fibrin glue
• After surgery
• With autoimmune diseases and certain cancers

Sometimes the cause is unknown.

The disease is similar to hemophilia, except bleeding into joints is less common. In the inherited form of Factor V deficiency, a family history of a bleeding disorder is a risk factor.

Excessive bleeding with menstrual periods and after delivery often occurs. Men and women are affected equally. About 1 person per 1 million has the disorder.

Symptoms:

• Bleeding into the skin
• Bleeding of the gums
• Excessive bruising
• Excessive menstrual bleeding
• Nosebleeds
• Prolonged or excessive loss of blood with surgery or trauma
• Umbilical stump bleeding

Signs and tests:

• Factor V assay showing decreased activity
• Normal thrombin time
• Prolonged partial thromboplastin time
• Prolonged prothrombin time
• Slightly prolonged bleeding time (in some people)

Treatment:

You should receive fresh blood plasma or fresh frozen plasma infusions during a bleeding episode or after surgery. These treatments will correct the deficiency temporarily.

Support Groups:

You can often help the stress of illness by joining a support group where members share common experiences and problems.

Expectations (prognosis):

The outlook is good with diagnosis and proper treatment.

Complications:

Severe bleeding (hemorrhage) could occur.

Calling your health care provider:

Go to the emergency room or call the local emergency number (such as 911) if you have an unexplained or prolonged loss of blood.

Prevention:

This is an inherited disorder; there is no known prevention.