Causes, incidence, and risk factors: Von Willebrand disease is caused by a deficiency of von Willebrand factor. Von Willebrand factor helps platelets to clump together and stick to�the blood vessel wall, which is necessary for normal blood clotting.
VonWillebrand disease�affects both�men and women. Most cases are mild. Bleeding may occur after surgery or when you have a tooth pulled. Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) can make this condition worse.�Bleeding may decrease during pregnancy.
A family history of a bleeding disorder is the primary risk factor. In women with heavy or prolonged menstrual bleeding, Von Willebrand is more common in Caucasian women than African American women.
Signs and tests: - Normal platelet count
- Prolonged bleeding time
- Reduced von Willebrand factor level
- Reduced platelet aggregation (platelet aggregation test)
- Ristocetin co-factor is reduced
This disease may also alter the results of the following tests:
- Factor VIII level
- Von Willebrand factor multimers
Treatment: Medications�such as desamino-8-arginine vasopressin (DDAVP) can be given to raise the levels of von Willebrand factor, which will reduce�the tendency toward bleeding.
Blood plasma or certain factor VIII preparations may also be used to decrease bleeding.
Some types of von Willebrand disease do not respond to DDAVP. Tests should be done to determine a patient's�specific type of von Willebrand disease, before trauma or surgery occurs. A trial of DDAVP can be done prior to surgery to test whether von Willebrand factor levels increase.
Expectations (prognosis): Women who have this condition generally do not experience excessive bleeding during childbirth.
Since this disease is inherited, genetic counseling may be recommended for parents.
Complications: Post-operative hemorrhage (bleeding) may occur.
If you have von Willebrand disease, do not take nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin or ibuprofen without talking to your health care provider.
Calling your health care provider: Call your health care provider if bleeding occurs without reason.
If you have von Willebrand disease and�are scheduled for surgery or are in an accident, be sure you or your family notify the health care providers about your condition.
References: Kumar V, Abbas AK, Fausto N. Robbins and Cotran Pathologic Basis of Disease. 7th ed. St. Louis, Mo: WB Saunders; 2005:654-655.
Noble J. Textbook of Primary Care Medicine. 3rd ed. St. Louis, Mo: Mosby; 2001:1047.
Marx J. Rosens Emergency Medicine: Concepts and Clinical Practice. 5th ed. St. Louis, Mo: Mosby; 2002:1693.
