Von Willebrand Disease

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Contents

Name of Condition

Von Willebrand Disease (VWD)

Definition

Von Willebrand Disease is an inherited bleeding disorder that affects blood clotting. It is the most common bleeding disorder. A genetic mutation causes the protein known as "Von Willebrand Factor" to be either missing or nonfunctional. This protein normally helps blood clot so without it, people with this disorder experience heavy or prolonged bleeding.

Description, Signs and Symptoms

Von Willebrand Disease is divided into several different types. Type 1 is the most common and the least severe, normally requiring treatment only for surgery or physical trauma. Small amounts of Von Willebrand Factor are present allowing clotting to occur in small cases. Type 2 has the clotting factors present, but they do not function properly, and is divided into Type 2A, 2B, 2M, and 2N. Type 3 is the most severe but it is also very rare. In Type 3, no Von Willebrand factors are present and severe bleeding may occur, such an internal bleeding, or excessive bleeding from only minor injury.

Inheritance

Type 1 and rare cases of Type 2 VWD are inherited in an autosomal dominant pattern. Most of Type 2 and Type 3 are inherited by an autosomal recessive pattern.

The disorder is caused by mutations in the VWF gene, which codes for the clotting factor proteins. The type of error in the gene results in the varying phenotypes of the condition, ranging from mild bleeding to severe.

Demographics

The prevalence of this disorder is difficult to estimate because of the range of types. Type 1 is the most common, and can occur in up to 1% of the population. Type 2 and 3 are less common, however can still occur at a rate of approximately 1 in 1000 people.

Diagnosis

Type 1 and Type 2 may not be diagnosed until after the occurrence of a major bleeding incident. Type 3 will be more obvious early on and is usually diagnosed in the first year of life. Blood tests may also help diagnose the disease, by measuring Von Willebrand factors.

Treatment and Management

Most people can take medications to control bleeding at times when it is necessary, such as people with milder forms of the disease who are undergoing surgery or have been in an accident, or for women who have unusually heavy menstruation. As a standard treatment for these people, a doctor may recommend:

  • Desmopressin (DDAVP), a synthetic hormone that makes your body release more von Willebrand factor and factor VIII into your bloodstream.
  • Von Willebrand factor replacement therapy
  • Antifibrinolytic drugs to help prevent the breakdown of blood clots
  • Fibrin glue, a medicine that can be placed directly on a wound to stop the bleeding

Treatments for women who have VWD with heavy menstrual bleeding include:

  • Combined oral contraceptives (birth control pills)
  • A levonorgestrel intrauterine device
  • Aminocaproic acid or tranexamic acid, drugs that help prevent the breakdown of blood clots

Prognosis

With proper care and treatment, along with early diagnosis, most types of Von Willebrand Disease are highly manageable and people with this condition can live essentially normal lives. It is especially important during childhood that people who may be responsible for the child, such as teachers, understand the child's condition and be able to react appropriately if an injury were to happen.

Resources

AccessDNA.com - von Willebrand disease[1]

http://www.nhlbi.nih.gov/health/dci/Diseases/vWD/vWD_WhatIs.html

http://www.hemophilia.org/NHFWeb/MainPgs/MainNHF.aspx?menuid=182&contentid=47&rptname=bleeding

References

http://www.nhlbi.nih.gov/health/dci/Diseases/vWD/vWD_WhatIs.html

http://www.hemophilia.org/NHFWeb/MainPgs/MainNHF.aspx?menuid=182&contentid=47&rptname=bleeding

http://ghr.nlm.nih.gov/condition=vonwillebranddisease

http://www.mayoclinic.com/health/von-willebrand-disease/DS00903

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