Von Willebrand Disease (vWD) is a bleeding disorder named after the man who discovered it, Erik Adolf von Willebrand. A child with vWD has a low level of the clotting factor von Willebrand factor (vWF). VWF helps blood form clots to stop bleeding from cuts or injury. When a child has vWD, their body has a hard time stopping a bleed.
VWD is the most common bleeding disorder that is passed down from a child's mother or father. About 1% of the general population has vWD. There are 3 types of vWD: type 1, type 2 and type 3.
VWD affects males and females equally. Many with vWD go their entire life without being diagnosed. Women are diagnosed more often because of heavy menstrual bleeding.
The Role of von Willebrand Factor
Von Willebrand factor (vWF) has two major jobs. One is to carry and protect the factor VIII(8) coagulation protein. The other job is to act as a glue to help blood platelets stick to the site of injury to help create a blood clot.
Types of von Willebrand Disease
There are 3 types of von Willebrand Disease (vWD):
Type 1
- Most common form of vWD
- von Willebrand factor is made in smaller amounts
- Mildest form of vWD
Many have:
- Nose bleeding
- Gum bleeding
- Excess menstrual bleeding
Type 2
- More bleeding than in type 1
- von Willebrand factor doesn't’t work normally
- Has four subtypes
Type 3
- Most severe form of vWD and a more serious bleeding disorder
- Bleeding more often
- von Willebrand factor is very low or absent
How Does a Child Get von Willebrand Disease?
von Willebrand Disease (vWD) is a genetic condition that is passed down from a child’s mother or father. Everyone is made up of two chromosomes and inherits them from their parents. Boys and men have an X and a Y chromosome. They get an X from their mother and a Y from their father. Girls and women have two X. They get an X from their mother and an X from their father. The von Willebrand gene occurs equally in men and women.
A mother with the vWD gene can have a:
A father with the vWD gene can have a:
A father and mother who have the vWD gene can have a:
Common Signs of von Willebrand Disease
- Continued bleeding after dental work, especially after a tooth is removed
- Frequent or easy bruising
- Frequent or long nosebleeds
- Heavy or long menses (periods) in girls and women
- A history of any of the above in one or more of your family members
How Does a Doctor Diagnose von Willebrand Disease?
There are special blood tests that will find out if a child has von Willebrand Disease (vWD). These tests are usually done by a hematologist (a doctor who specializes in blood diseases). The blood tests measure how much von Willebrand factor a child has and how well it is doing its two jobs, carrying factor VIII by measuring factor VIII in the blood, and acting as the glue for platelets with a test called the Ristocetin cofactor activity.
Why is von Willebrand Disease Difficult to Diagnose?
Sometimes it is difficult to determine if a child has von Willebrand Disease (vWD). This is because there are many things that affect von Willebrand factor and factor VIII (8) in a child's body. For example, stress can raise the factor level in a child with vWD, but may appear to have normal test results. Hormones can also affect a child’s factor levels. For this reason, girls should be tested on the first day of their menses (period) because this is when a girl's hormone levels are the lowest.
If there is a history of vWD in a child’s family or a strong history of bleeding, doctors may have to repeat blood tests a few times to find out if a person has vWD.
Treatment of von Willebrand Disease
There are several types of von Willebrand Disease. Each one affects how well blood clots. The type of treatment depends on:
- Type of von Willebrand Disease (vWD)
- Severity of bleeding
- How a child responds to different treatments
For mild types of vWD:
Desmopressin (DDVAP) is usually used as treatment. DDVAP causes a temporary rise in von Willebrand factor (vWF) and may last a few hours.
For some type 2 and all type 3:
Intravenous infusion (into a vein) of a special medicine called factor that contains both factor VIII and vWF is usually used as treatment. This results in a temporary rise in vWF and lasts less than a day.
For severe bleeding:
Repeated intravenous infusions (into a vein) of a factor product that has both factor VIII and vWF may be needed for treatment.
Von Willebrand Disease and Women
Von Willebrand Disease (vWD) can be more challenging for girls and women because of the risk for heavy menses (periods) and bleeding after childbirth. Once a girl or woman is diagnosed and they are given the correct treatment, these normal life events can be managed safely.
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