What Is von Willebrand Disease?

Von Willebrand disease (VWD) is a bleeding disorder. It affects your blood's ability to clot. If your blood doesn't clot, you can have heavy, hard-to-stop bleeding after an injury. The bleeding can damage your internal organs or even cause death, although this is rare.

In VWD, you either have low levels of a certain protein in your blood, or the protein doesn't work the way it should. The protein is called von Willebrand factor, and it helps the blood clot.

Normally, when one of your blood vessels is injured, you start to bleed. Small blood cell fragments called platelets (PLATE-lets) clump together to plug the hole in the blood vessel and stop the bleeding. Von Willebrand factor acts like glue to help the platelets stick together and form a blood clot.

Von Willebrand factor also carries clotting factor VIII (8), another important protein that helps your blood clot. Factor VIII is the protein that's inactive or missing in people who have hemophilia, another clotting disorder.

VWD is more common and usually milder than hemophilia. In fact, VWD is the most common of all the inherited bleeding disorders. It occurs in about 1 out of every 100 to 1,000 people. VWD affects both males and females, while hemophilia mainly affects males.

Types of von Willebrand Disease

There are three major types of VWD.

Type 1

In type 1 VWD, you have a low level of von Willebrand factor, and you may have lower than normal levels of factor VIII. This is the mildest and most common form of VWD. About 3 out of 4 people who have VWD have type 1.

Type 2

In type 2 VWD, the von Willebrand factor doesn't work the way it should. Type 2 is divided into subtypes: 2A, 2B, 2M, and 2N. Different gene mutations (changes) cause each type, and each is treated differently. So it's important to know the exact type of VWD that you have.

Type 3

In type 3 VWD, you usually have no von Willebrand factor and low levels of factor VIII. Type 3 is the most serious form of VWD, but it's very rare.

Overview

Most people who have VWD have type 1, a mild form. This type usually doesn't cause life-threatening bleeding. You may need treatment only if you have surgery, tooth extraction, or trauma. If you need treatment, medicines and medical therapies are used.

Some people who have severe forms of VWD need emergency treatment to stop bleeding before it becomes life threatening.

Early diagnosis is important. With the right treatment plan, even people who have type 3 VWD can live normal, active lives.

Revised May 2009