Definition
Von Willebrand’s disease is a hereditary bleeding disorder caused by a deficiency of von Willebrand factor. Von Willebrand factor helps platelets to stick to the blood vessel wall and to each other, which is necessary for normal blood clotting.

Causes, incidence, and risk factors
Von Willebrand’s disease is the most common hereditary bleeding disorder. It affects both sexes approximately equally. Most cases are mild, and bleeding may occur after a surgical procedure or tooth extraction. The condition is worsened by the use of aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs). Bleeding may decrease during pregnancy.

The disease is very common, affecting at least 1% of the population. A family history of a bleeding disorder is the primary risk factor. In women with heavy or prolonged menstrual bleeding, Von Willebrand’s is more common in Caucasian women than African American women.

Symptoms

 
• Nose bleeds  
• Bleeding of the gums  
• Abnormal menstrual bleeding  
• Bruising  
• Skin rash

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

For most patients, bleeding is mild under most circumstances. However, if trauma occurs or surgery is scheduled, cryoprecipitate or DDAVP can be given to raise the levels of von Willebrand factor, which will decrease the tendency toward bleeding. Fresh plasma or certain factor VIII preparations may also be used to decrease bleeding.

Some subtypes of von Willebrand disease do not respond to DDAVP. Because of this, the subtype should be determined prior to reliance on DDAVP for a significant bleeding challenge. In addition, a trial of DDAVP can be done prior to surgery to test whether von Willebrand factor levels increase.

Patients with this disorder should not take nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin or ibuprofen without consulting their health care provider.

Expectations (prognosis)

Women who have this condition generally do not experience excessive bleeding during childbirth.

Life span is usually normal. Since this disease is genetically transmitted, genetic counseling may be recommended for parents.

Complications
Post-operative hemorrhage (bleeding) may occur.

Calling your health care provider
Call your health care provider if bleeding occurs with no reason.

If you have this disorder and are scheduled for surgery or are in an accident, be sure to notify the health care providers about your condition.

Medical Encyclopedia

All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.