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What Is Von Willebrand Disease?
Von Willebrand disease (VWD) is a disorder that makes it hard for your blood to clot. This happens because you don't have enough of a clotting protein called von Willebrand factor (VWF). It could also happen because you have a type of VWF that doesn't work well. If you have von Willebrand disease, a cut, accident, or surgery can result in bleeding that's hard to stop.
VWD is the most common inherited bleeding disorder. That means you get it from your parents. It affects an estimated 1 in 100 to 1 in 1,000 people.
There are three types of inherited VWD and one type of the disorder that isn't hereditary.
Type 1: This is the most common form of inherited VWD. About 60% to 80% of people with VWD have this type. With Type 1, you don't have enough von Willebrand factor in your blood. Typically, you have 20% to 50% of normal levels. Symptoms of Type 1 VWD are mild.
Type 2: This is the second most common form of inherited VWD. It's caused by your own VWD factor not working well. If you have VWD, there's a 15% to 30% chance you have Type 2. Symptoms range from mild to moderate.
Type 3: This is the rarest form of inherited VWD. It's found in 5% to 10% of cases. If you have this type, you typically have no von Willebrand factor and very low levels of another protein needed for clotting. Type 3 has the most severe symptoms.
Acquired: It's possible to get this form of VWD if you have an autoimmune disease, like lupus. An autoimmune disease is one where your body's natural defense system (immune system) fights itself. You can also get acquired VWD after taking certain medications, or from heart disease or some types of cancer.
Most of the time, you inherit VWD from one or both parents. You can inherit Type 1 or Type 2 if one of your parents passes the gene on to you. You usually only get Type 3 if both of your parents pass the gene to you.
It's possible to have the gene that causes the disorder but not have any symptoms. In that case, you can still pass the gene to your children.
It depends on what type of von Willebrand disease you have.
With Type 1 and Type 2, your symptoms can range from mild to moderate. They include:
If you're a woman with VWD, you'll have periods with clots larger than an inch in diameter. This means you may need to change your pad or tampon more than every hour. You'll also likely develop anemia (low iron in the blood). These are symptoms of von Willebrand disease, but by themselves, they don't prove you have VWD.
With Type 3, you may have all the symptoms of Type 1 and Type 2, plus episodes of severe bleeding for no reason. You also might experience severe pain and swelling in your soft tissues and joints because of bleeding.
If your doctor suspects you have von Willebrand disease, they'll start with a detailed medical history. Remember, VWD is almost always inherited. Your family medical history will show if you've experienced typical symptoms or if other relatives have a bleeding disorder or symptoms of one.
You might have to take a clotting test to see how well your blood can form a clot and how long it takes. Your doctor may also order several blood tests, such as an antigen test. This shows how much VWF you have in your blood plasma.
Levels of VWF go up and down because of things like stress and exercise. For this reason, you might have to have these tests more than once to confirm the results.
There's no cure for von Willebrand disease, but it can be treated and/or managed. A key to managing this disorder is to reduce the risk of bleeding before it starts. This means avoiding certain drugs that can thin your blood. Your doctor might recommend you avoid aspirin and medications known as NSAIDs, such as ibuprofen (Advil, Motrin) and naproxen (Aleve). Acetaminophen (Tylenol) is a good alternative to aspirin and NSAIDs.
How your condition is treated will depend on how severe your symptoms are.
With Type 1, you typically only need treatment if you have had surgery, a tooth extraction, or are injured.
The most common treatment for von Willebrand disease is desmopressin acetate (DDAVP). It's available as an injection or a nasal spray. DDAVP is a synthetic form of the hormone vasopressin. It causes the release of von Willebrand factor from your cells. A side effect of this hormone is that it causes your body to retain water. As a result, you will need to be on fluid restrictions if you're taking the medication. Desmopressin also carries an FDA black box warning for the risk of hyponatremia, especially in children and older adults.
Your doctor might also recommend that you get clotting factor concentrates through an IV.
If you're going to have a dental procedure, you may need to take aminocaproic acid or tranexamic acid. These prevent the breakdown of blood clots. You take these medications by mouth, either in liquid or pill form. You may also take them if you're bleeding from your nose or mouth, or if you have heavy bleeding with your period.
If you're a woman with VWD and heavy periods, your treatment may also include birth control pills. These can increase the amount of von Willebrand factor in your blood. Another possible treatment is a levonorgestrel intrauterine device. This is a type of birth control that contains the hormone progestin. If you're done having children or don't want any, you can also have an endometrial ablation. This procedure destroys the lining of the uterus and reduces the amount of blood you lose during your period.
If you have Type 3 and are experiencing bleeding, you need to get treatment right away. Bleeding episodes can be fatal if not treated immediately.
Von Willebrand Disease And Your Immune System
Von Willebrand disease is a blood-clotting disorder that usually develops as an inherited, genetic mutation. People with this mutation lack a specific protein called the von Willebrand factor, which helps your platelets form blood clots.
In rare cases, though, you could develop this condition without inheriting it. Known as acquired von Willebrand disease, this particular type of the disorder can be caused by medications or other medical conditions — including autoimmune disorders. It isn't an autoimmune disorder exactly but acquired von Willebrand disease usually occurs alongside these types of conditions.
In this article, you'll learn more about acquired von Willebrand disease, how it's linked to autoimmune disease, and what conditions could put you at risk of developing this bleeding disorder.
Von Willebrand disease can be considered an autoimmune disorder in rare cases, but acquired versions of this disease usually develop as a result of other autoimmune conditions, diseases, or medications. When it develops as an autoimmune disease, for one reason or another, your body's own immune system attacks the von Willebrand protein, destroying it or reducing its clotting power.
There is currently no good estimate of how many people have the acquired form of von Willebrand disease.
What is an autoimmune disease?An autoimmune disease is a condition where your body — specifically your immune system — attacks its own tissues. There are more than 80 known autoimmune diseases, and they can be passed on through families or acquired during your lifetime.
There is no cure for most autoimmune diseases, and treatment may have to continue throughout your life to keep symptoms under control.
There's a lot that's still not understood when it comes to autoimmune diseases. Autoimmune diseases can impact several body systems at once, and about a quarter of all people with one autoimmune condition will go on to develop other autoimmune diseases, as well.
One of the leading theories about how autoimmune disease causes von Willebrand disease is in the activation of von Willebrand factor proteins. In many cases of acquired von Willebrand disease, the von Willebrand factor protein has an abnormal clearance level. Enhanced or elevated clearance levels of the von Willebrand factor have also been linked to the development of the inherited Type 1 variety of von Willebrand's disease.
What autoimmune conditions can cause VWD?
Acquired von Willebrand disease has been linked to a number of triggers. The autoimmune diseases most often connected with this disorder include:
Beyond autoimmune diseases, the following other nonautoimmune conditions have also been linked to acquired von Willebrand disease:
Von Willebrand disease is primarily considered a blood clotting disorder, but there have been some studies that have connected blood clotting problems to immune function.
There are shared pathways in the body systems that launch clotting as well as immune responses. A disruption in one part of this pathway is believed to impact multiple body functions, but more research is needed to fully understand the connection.
Von Willebrand disease is a blood clotting disorder that usually develops from an inherited genetic condition but can — in rare cases — develop alongside an autoimmune disease or other disorder, with certain medications, or as its own autoimmune problem.
Talk with your doctor if you have several chronic medical conditions, especially autoimmune disorders like lupus, and you begin to notice things like increased nosebleeds or unexplained bruising. Acquired forms of this disease can often be resolved by treating the underlying cause.
What Do Blood Tests For Von Willebrand Disease Measure?
To help diagnose von Willebrand disease or other bleeding disorders, a doctor will request various blood tests. These tests will measure the presence and activity of certain substances in the blood.
Von Willebrand disease (VWD) is a blood-clotting disorder. It occurs when a person has insufficient or ineffective supplies of a substance in the blood known as von Willebrand factor (VWF). This is a protein that plays an important role in the process of forming a blood clot.
Typically, after an injury where bleeding occurs, VWF in the blood attaches to small blood cells known as platelets. This helps the platelets stick together and form a clot at the site of injury to stop bleeding. However, with ineffective or low levels of VWF, the clot may take longer to form or form incorrectly. This may result in a person experiencing excessive bleeding.
To help diagnose VWD, a healthcare professional will order blood tests. These tests will evaluate the blood for substances in the blood that promote blood clotting. For example, this includes measuring the amount, activity, and structure of VWF.
To help diagnose VWD and other bleeding disorders, a doctor will request a number of blood tests. Typically, a person may need to repeat these tests several times to receive an accurate diagnosis. This is because multiple factors, such as stress, infections, and pregnancy, can affect the levels of clotting factors in the blood.
The results of these tests can also help a doctor identify which type of VWD a person has. One test to help diagnose VWD is known as the VWF antigen test.
VWF is a protein in the blood that aids coagulation by acting as a glue that sticks platelets together at the site of injury. Additionally, VWF further affects clotting by influencing the availability of clotting factor VIII, which is another important protein in the formation of blood clotting.
If VWF does not function correctly, or there is too little available, a person is unable to form a platelet plug, or it takes too long to form one. As such, this test measures the amount of VWF and determines how well it functions.
VWF is a multimeric protein, which consists of multiple polypeptide chains, which themselves are chains of amino acids, also known as the building blocks of proteins. These chains help VWF perform its functions of interacting with platelets and factor VIII.
As such, the multimer test measures HMW multimers, as low levels can suggest VWD.
To form a blood blot, VWF must also bind to blood clotting factor VIII to help stimulate the coagulation cascade, which activates proteins that enable clotting. Factor VIII is one of many coagulation factors that also play an important role in hemostasis.
VWF plays a protective role and prevents the breakdown of factor VIII. As such, low levels of VWF have links to a decrease in factor VIII levels. Therefore, it is helpful to measure the amount of factor VIII in the blood when diagnosing VWD.
A deficiency in factor VIII may also relate to hemophilia A, which is another type of bleeding disorder.
Von Willebrand disease is a condition that affects the blood's ability to clot. It occurs due to a deficiency or problem with von Willebrand factor. This is a protein that plays an important role in the initial formation of a blood clot.
To help diagnose the condition, a doctor will order a number of blood tests. These tests will measure the amount, activity, and structure of certain substances, such as von Willebrand factor, in the blood. Low levels or activities of these substances may suggest a person has von Willebrand disease.
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