Von Willebrand Disease (VWD)
Understanding VWD
Although referred to as a single disease, Von Willebrand Disease (VWD) is in fact a family of bleeding disorders caused by an abnormality of the von Willebrand factor (VWF). A congenital bleeding disorder characterized by a lifelong tendency toward easy bruising, frequent nose bleeds and heavy or prolonged menstrual bleeding, VWD is the most common hereditary bleeding disorder.
Symptoms of VWD
People with von Willebrand Disease (VWD) experience frequent nosebleeds, easy bruising and excessive bleeding during and after invasive procedures, such as tooth extractions and surgery. Women often experience heavy menstrual periods that last longer than average, and hemorrhaging after childbirth.
There are three main types of VWD based on qualitative or quantitative defects in VWF. Qualitative refers to the quality, or how well VWF works. Quantitative refers to the amount of VWF present. A fourth type, acquired VWD, is not hereditary.
- Type 1 VWD is found in 60%-80% of patients
People with type 1 VWD have a quantitative deficiency of VWF. Levels of VWF in the blood range from 20%-50% of normal. The symptoms are usually mild. - Type 2 VWD is found in 15%-30% of patients
People with type 2 VWD have a qualitative deficiency in their VWF. Type 2 is broken down into four subtypes: type 2A, type 2B, type 2M and type 2N, depending on the presence and behavior of multimers, molecular chains of VWF. Symptoms are mild to moderate. - Type 3 VWD is found in 5%-10% of patients
People with type 3 VWD have a quantitative deficiency of VWF. Symptoms are typically severe, and include spontaneous bleeding episodes, often into their joints and muscles. - Acquired VWD
This type of VWD in adults results after a diagnosis of an autoimmune disease, such as lupus, or from heart disease or some types of cancer. It can also occur after taking certain medications.
Diagnosing VWD
Many patients with bleeding disorders are diagnosed and treated at one of the federally funded hemophilia treatment centers (HTCs) that are located throughout the country. HTCs provide comprehensive care from skilled hematologists and other professional staff, including nurses, physical therapists, social workers and sometimes dentists, dieticians and other healthcare providers.
A medical health history is important to help determine if other relatives have been diagnosed with a bleeding disorder or have experienced symptoms. Tests that evaluate clotting time and a patient's ability to form a clot may be ordered. A clotting factor test, called an assay, and tests measuring platelet function also may be performed. The VWF antigen test measures the amount of VWF in blood plasma. Patients with VWD typically have < 50% of normal VWF in their plasma. After VWD is confirmed, a test to determine the exact type is performed.
It should be noted that diagnostic testing to confirm von Willebrand Disease (VWD) may have to be repeated because levels of VWF fluctuate. VWF can rise due to stress, exercise, the use of oral contraceptives, pregnancy and hyperthyroidism.
Treating VWD
Treatment for von Willebrand Disease (VWD) depends on the diagnosis and severity. The mainstay of treatment is desmopressin (DDAVP®), the synthetic version of a natural hormone vasopressin. It stimulates the release of VWF from cells, which also increases FVIII. Desmopressin comes in two forms: injectable and nasal spray.
There are a few clotting factor concentrates that are rich in VWF, and are recommended for patients with VWD. These therapies are given by intravenous infusion.
Aminocaproic acid and tranexamic acid are antifibrinolytics agents that prevent the breakdown of blood clots. These drugs are often recommended before dental procedures, to treat nose and mouth bleeds, and for heavy or prolonged menstrual bleeding. Antifibrinolytics are taken orally, as a tablet or liquid. The Medical and Scientific Advisory Council (MASAC) of the National Hemophilia Foundation recommends that a dose of clotting factor be taken first to form a clot, then aminocaproic acid, to preserve the clot and keep it from being prematurely broken down.
Websites:
- Centers for Disease Control and Prevention
- National Hemophilia Foundation
- National Heart, Lung and Blood Institute
- World Foundation of Hemophilia
Support Groups:
References:
The information provided on this website is not medical advice, nor is it intended to be a substitute for medical advice, diagnosis, and treatment. Always seek the advice of a physician or other qualified health provider with questions concerning a medical condition. Never disregard professional medical advice, or delay seeking it based on information provided on this website.
