This is an inherited disorder that causes prolonged clotting (coagulation) of blood in a test tube without a clinical bleeding tendency, and results from a deficiency of the plasma protein factor XII.
Causes, incidence, and risk factors
Factor XII deficiency is a hereditary disorder that is usually found when clotting tests are done for routine screening. It is not associated with abnormal bleeding , and is a rare disorder.
Signs and tests
Prolonged partial thromboplastin time
Abnormal Factor XII assay
Treatment
Treatment is generally unnecessary.
Expectations (prognosis)
The outcome is expected to be good, even without treatment.
Complications
There are usually no complications.
Calling your health care provider
This condition is usually discovered by the health care provider when prolonged clotting is noticed in the process of running other laboratory tests.
Prevention
This is an inherited disorder. There is no known way to prevent it.