Von Willebrand disease

Answer 1

Definition

Von Willebrand disease is the most common hereditary bleeding disorder.

Causes, incidence, and risk factors

Von Willebrand disease is caused by a deficiency of von Willebrand factor. Von Willebrand factor helps blood platelets clump together and stick to the blood vessel wall, which is necessary for normal blood clotting. There are several types of Von Willebrand disease.

Von Willebrand disease affects men and women equally. 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 in African American women. The majority of women with heavy or prolonged menstrual bleeding do NOT have Von Willebrand disease.

Symptoms

• Abnormal menstrual bleeding
• Bleeding of the gums
• Bruising
• Nosebleeds
• Skin rash

Signs and tests

Tests that may be done to diagnose this disease include:

• Bleeding time(is prolonged)
• Platelet aggregation test
• Platelet count(may be low or normal)
• Ristocetin cofactor test (the primary assay test used to diagnose von Willebrand disease)
• Von Willebrand factor level (level is reduced)

This disease may also alter the results of the following tests:

• Factor VIII level
• Von Willebrand factor multimers (parts of the von Willebrand factor protein molecule)

Von Willebrand disease may be hard to diagnose. Low von Willebrand factor levels and bleeding do not always mean you have von Willebrand disease.

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.

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 before surgery to test whether von Willebrand factor levels increase.

The drug Alphanate (antihemophilic factor) is approved to decrease bleeding in patients with the disease who must have surgery or any other invasive procedure.

Blood plasma or certain factor VIII preparations may also be used to decrease bleeding.

Expectations (prognosis)

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

This disease is passed down through families. Therefore, genetic counseling may help prospective parents understand the risk to their children.

Complications

Bleeding (hemorrhaging) may occur after surgeries or other invasive procedures.

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

Kessler CM. Hemorrhagic disorders: coagulation factor deficiencies. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 180.

Answer 2

Definition

Von Willebrand disease is the most common hereditary bleeding disorder.

Causes, incidence, and risk factors

Von Willebrand disease is caused by a deficiency of von Willebrand factor. Von Willebrand factor helps blood platelets clump together and stick to the blood vessel wall, which is necessary for normal blood clotting. There are several types of Von Willebrand disease.

A family history of a bleeding disorder is the primary risk factor.

Symptoms

• Abnormal menstrual bleeding
• Bleeding of the gums
• Bruising
• Nosebleeds
• Skin rash

Note: Most women with heavy or prolonged menstrual bleeding do not have Von Willebrand disease.

Signs and tests

Von Willebrand disease may be hard to diagnose. Low von Willebrand factor levels and bleeding do not always mean you have von Willebrand disease.

Tests that may be done to diagnose this disease include:

• Bleeding time
• Blood typing
• Factor VIII level
• Platelet aggregation test
• Platelet count
• Ristocetin cofactor test
• Von Willebrand factor specific tests

Treatment

Treatment may include DDAVP (desamino-8-arginine vasopressin), a medicine to raise von Willebrand factor level and reduce the chances for bleeding.

However, DDAVP does not work for all types of von Willebrand disease. Tests should be done to determine what type of von Willebrand you have. If you are going to have surgery, your doctor may give you DDAVP before surgery to see if your von Willebrand factor levels increase.

The drug Alphanate (antihemophilic factor) is approved to decrease bleeding in patients with the disease who must have surgery or any other invasive procedure.

Blood plasma or certain factor VIII preparations may also be used to decrease bleeding.

Expectations (prognosis)

Bleeding may decrease during pregnancy. Women who have this condition usually do not have excessive bleeding during childbirth.

This disease is passed down through families. Genetic counseling may help prospective parents understand the risk to their children.

Complications

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. Do not take these medicines without first talking to your doctor or nurse.

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

Kessler CM. Hemorrhagic disorders: coagulation factor deficiencies. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 180.

Reviewed By

Review Date: 02/16/2012

Todd Gersten, MD, Hematology/Oncology, Palm Beach Cancer Institute, West Palm Beach, FL. Review provided by VeriMed Healthcare Network. Also reviewed by Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington; David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.