von Willebrand Disease
The human blood contains platelets that stick to holes in blood vessels and patch them up. In a way, platelets are like a built-in bandage. They stick to a wound and to each other to help form clots that stop the bleeding. This "sticky" factor is a protein called von Willebrand, named for the scientist who discovered it.
Sometimes the human body doesn't contain enough of the von Willebrand protein, or the protein doesn't work like it should. When this happens, the platelets don't do their job and a wound can bleed for a very long time. Fortunately, with the proper treatment, children, teens and adults can live healthy, active lives.
The hematology team at Cook Children's has a great deal of experience in diagnosing and treating children, teens and young adults with this disorder. We offer a full range of services from diagnosis to treatment.
Von Willebrand disease (VWD) is an inherited, or genetic, bleeding disorder, meaning it is passed down through families in gene cells. It is the most commonly inherited bleeding disorder. When you have von Willebrand disease, your body doesn't have enough of the von Willebrand protein, so your platelets can't stick.
The blood contains twelve factors that work together to make your blood clot, or on the surface to scab over, so that you can stop bleeding. People with von Willebrand are missing one of the factors, the von Willebrand factor, or only have a small amount of that factor.
There are three major types of von Willebrand disease:
- Type 1 von Willebrand disease is the mildest form of the disease. If your child has been diagnosed with type 1 von Willebrand disease, this means that they have the von Willebrand factor, just not enough of it for their blood to clot correctly. They may also be low on Factor VIII, another of the twelve clotting factors. Approximately three out of four cases are type 1.
- Type 2 von Willebrand disease means that there is an abnormality in the von Willebrand factor, meaning the factor is non-functioning. The patient may also have a decreased amount of the factor, as well. Type 2 is divided into subtypes: 2A, 2B, 2M, and 2N. Different gene mutations (changes) cause each type, and each is treated differently. Thus, it's important to know the exact type of 6WD that you have.
- Type 3 von Willebrand disease is the most severe form of the disease, and the rarest. People with type 3 have little or no von Willebrand factor and quite often have little Factor VIII, so the blood cannot clot.
Von Willebrand disease is a genetic disorder that is inherited from one or both parents. Type 1 and type 2 von Willebrand disease are usually, though not always, the result of inheriting the gene from one parent. Sometimes, both parents can have the gene that causes the disease. When that happens, the child may inherit both genes, which typically results in type 3 von Willebrand.
If an adult has the disease, there is a fifty percent chance that their children will inherit the defective gene.
Von Willebrand occurs equally in both boys and girls, across all ethnic and socio-economic groups. For girls, disease can become more complex after the start of menstruation.
Many people with von Willebrand disease have very mild symptoms, and some people never have any symptoms. The most common sign that there is a problem is abnormal bleeding. And even then, the disease may go unnoticed. People with von Willebrand don't bleed more than other people, they bleed longer. In fact, they typically bleed very slowly. This is sometimes called oozing.
People with cuts or nosebleeds ooze on the outside where the blood can be seen. Oozing can also happen on the inside of the skin, like a bruise. Internal oozing happens deep inside the body where it can't be seen. Sometimes internal bleeding will cause pain or swelling; because the bleeding can't be seen, this can put a person at increased risk for illness or even death.
Some of the more common symptoms that may appear include, but are certainly not limited to:
- Bleeding from the gums after brushing or flossing the teeth, a visit to the dentist, or eating certain foods
- Bleeding after shaving with a razor
- Blood in the stool or urine
- Bruises that form lumps under the skin
- Cuts that bleed for an extended length of time
- Easy bruising
- Increased menstrual flow, sometimes resulting in anemia
- Recurrent and prolonged nosebleeds
There are many possible complications from von Willebrand disease, some of which are:
- Anemia, especially for women who experience heavy menstrual bleeding because they lose a lot of iron. This is actually referred to as iron deficiency anemia.
- Swelling and pain in the joints or soft tissue of the body caused by internal bleeding
- Death from bleeding can result when abnormal bleeding can't be controlled. For this reason, it is very important that if your child experiences a fall or hard hit he or she should be seen right away by your hematology specialist
- Bleeding due to medical or dental procedures. It is very important that your child's medical team be fully aware that he or she has von Willebrand disease prior to any procedure so that proper precautions can be taken to minimize any risk as much as possible.
- People with von Willebrand disease should avoid unnecessary trauma, including contact sports. If bleeding does occur, apply pressure to the area.
- During nosebleeds, pinch the end of the nose and have the child lean slightly forward to keep the blood from flowing down the throat.
- Because of the possibility of excessive bleeding, male infants who are at risk for the disease (those with a family history of the disease) should not be circumcised without a doctor's approval.
- Girls with von Willebrand disease who have started their periods might want to take extra pads or a change of clothes in case of accidents. Heavy menstrual bleeding can sometimes be controlled with birth control pills.
Call your doctor immediately if your child experiences any excessive or unexplained bleeding.
Because the symptoms can be mild, or internal, von Willebrand disease can be difficult to diagnose and often goes undetected. If your child has any symptoms of a bleeding disorder, or if there is a family history of von Willebrand disease, your pediatrician will refer you to a pediatric hematologist for testing.
The hematology team at Cook Children's will review your child's medical history, physical examination and tests to determine if your child has the disorder and, if so, the type and severity.
Your doctor will ask questions about your child's medical history, and that of your family. Other issues the specialist may ask about might include:
- Any bleeding from a small wound that lasted more than 15 minutes or started up again within the first 7 days following the injury
- Any prolonged, heavy, or repeated bleeding that required medical care after surgery or dental extractions
- Any bruising with little or no apparent trauma, especially if you could feel a lump under the bruise
- Any nosebleeds that occurred for no known reason and lasted more than 10 minutes despite pressure on the nose, or any nosebleeds that needed medical attention
- Any blood in your child's stools for no known reason
- Any heavy menstrual bleeding (for girls). This bleeding usually involves clots or lasts longer than 7 to 10 days
- Any history of muscle or joint bleeding
- Any medicines your child has taken that might cause bleeding or increase the risk of bleeding. Examples include aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs), clopidogrel, warfarin, or heparin
- Any history of liver or kidney disease, blood or bone marrow disease, or high or low blood platelet counts
During the physical exam, your doctor will look for:
- Unusual bruising
- Signs of recent bleeding
- Signs of liver disease
The doctor will typically perform one or more of the following tests:
- Factor VIII level test (also called factor VIII coagulant), which measures the level of factor VIII and its ability to function
- Von Willebrand factor antigen test (also called factor VIII antigen), which measures the amount of von Willebrand factor and von Willebrand activity (ristocetin cofactor or RCF). The disorder is considered mild if a person has 20% to 49% of the normal amount. It is severe if the amount is 5% or less. Patients with type O blood may have reduced levels of von Willebrand factors.
- Von Willebrand multimers test, which helps to classify the type of von Willebrand disease.
- Platelet function tests, which determine how well the platelets work.
- Genetic testing is recommended if one or both parents have von Willebrand disease since there is a 50% chance the child will inherit the disorder.
Tests may need to be done more than once because these levels may rise and fall over time in an individual. Also, the doctor will take a family medical history and recommend testing to see if other relatives have a bleeding disorder.
Currently, there is no cure for this lifelong disease; but there are medications designed to help you manage it. Treatment for von Willebrand disease (6WD) is based on the type of 6WD you have and how severe it is. Most cases of VWD are mild, and your child may need treatment only if they have surgery, tooth extraction, or an accident.
Your Cook Children's pediatric hematologist will work with you and your pediatrician to create a treatment plan that is based on the type of von Willebrand disease your child has and the severity, as well as your preferences.
Your doctor will take into consideration your child's health, other medications, and if there is a previous treatment history, that will be taken into consideration as well.
Medicines are used to:
- Increase the amount of von Willebrand factor and factor VIII released into the bloodstream
- Replace von Willebrand factor
- Prevent the breakdown of blood clots
- Control heavy menstrual bleeding in women
Based on your child's diagnosis and specific needs, medicines may include:
- Desmopressin (DDAVP) is a medication that is usually given through a nasal spray. It can also be given by injection in an arm or leg, or it can be given in an IV at the hospital. It may be given by injection or IV for testing purposes. DDAVP helps boost the amount of von Willebrand factor, so that the blood can clot. DDAVP is a synthetic hormone, similar the natural hormone vasopressin, that controls bleeding by stimulating the body to release more von Willebrand factor that is stored naturally in the lining of the blood vessels. This enhances factor VIII levels. DDVAP is effective in most cases of type 1 and some subtypes of type 2 von Willebrand disease.
- Another type of treatment is von Willebrand factor replacement therapy. This involves an infusion of concentrated von Willebrand factor and factor VIII into a vein in the arm. This treatment may be used if your child:
- Can't take desmopressin or needs extended treatment
- Have type 1 6WD that doesn't respond to desmopressin
- Have type 2 or type 3 6WD
- Patients with Type 3 (and some with Type 2A and 2B) will need treatment with Humate P, a medication derived from human plasma that contains both factor VIII and von Willebrand factor that is given intravenously. Patients with Type 1 also might receive Humate-P in certain situations, such as major trauma or major surgery, although they can generally be treated with desmopressin.
- Medication to inhibit the breakdown of blood clots also might be used, such as aminocaproic acid (Amicar).
For girls who have von Willebrand disease with heavy menstrual bleeding, your hematologist may recommend the following treatments:
- Birth control pills. The hormones in these pills can increase the amount of von Willebrand factor and factor VIII in your blood. The hormones also can reduce menstrual blood loss. Birth control pills are the most recommended birth control method for women who have VWD
- Aminocaproic acid or tranexamic acid. These antifibrinolytic medicines can reduce bleeding by slowing the breakdown of blood clots.
Treating major and potentially life-threatening bleeds:
- In emergency situations where your child is at risk for life-threatening bleeds, a factor concentrate containing both factor VIII and von Willebrand factor, such as Humate P, Alphanate or wilate, will usually be given.
- Patients with a type 2 von Willebrand disease known as pseudo platelet type will require a platelet transfusion administered by a hematologist.
It is critical that you are fully aware of the type of von Willebrand disease your child has. It is especially important to note to the medical team any unique circumstances that could put your child's life at risk.
There is a lot of medical data and information you must keep track of and in emergency or urgent care situations, it can be difficult to remember everything. For this reason we recommend that you download a copy of Cook Children's FREE Health Care Notebook. That way, you can have all of your child's medical information with you, and can simply hand the planner over to the emergency care or other medical care team. You can learn more about the planner and download a copy here.
We also recommend that you download the Emergency Care for Patients with von Willebrand Disease instructional manual for medical professionals and place a copy in your child's Health Care Notebook. Not all physicians are familiar with this disease, and this manual may help to reduce risk to your child in an emergency. We realize it can be uncomfortable to offer directions to a medical team, but you are your child's advocate. If you have questions or concerns, Cook Children's hematology team will be more than happy to discuss them with you. Our goal is to help assure that your child can enjoy as healthy, active and happy lifestyle as possible.
We are here to help.
If your child has been diagnosed, you probably have lots of questions. We can help. If you would like to schedule an appointment, refer a patient or speak to our staff, please call our offices at 682-885-4007.