What is Bernard-Soulier syndrome?
Bernard-Soulier syndrome is a platelet function disorder caused by an abnormality in the genes for glycoprotein Ib/IX/V. These genes code for a group of linked proteins normally found on the surface of platelets, the glycoprotein Ib/IX/V receptor (also called the von Willebrand factor or VWF receptor). Because this receptor is absent or is not working properly, platelets do not stick to the injured blood vessel wall the way they should and it is difficult for the normal blood clot to form.
Bernard-Soulier syndrome is an autosomal recessive disorder, meaning that both parents must carry an abnormal gene (even though they themselves don’t have the disease) and pass that abnormal gene on to their child. Like all autosomal recessive disorders, it is found more frequently in areas of the world where marriage between close relatives is common. Bernard-Soulier syndrome affects both males and females.
Symptoms of Bernard-Soulier syndrome vary from one individual to the next. Signs of the disorder are usually first noticed during childhood.
People with Bernard-Soulier syndrome may experience:
- Easy bruising
- Nose bleeds
- Bleeding from gums
- Heavy or prolonged menstrual bleeding (menorrhagia) or bleeding after childbirth
- Abnormal bleeding after surgery, circumcision, or dental work
- Rarely, vomiting blood or passing blood in stool due to bleeding from the gut (gastrointestinal hemorrhage)
Bernard-Soulier syndrome often causes more problems for women than men because of menstruation and childbirth.
The diagnosis of platelet function disorders requires a careful medical history and a series of laboratory tests that should be performed by a specialist at a haemophilia treatment centre.
In people with Bernard-Soulier syndrome:
- The bleeding time (a standardized test of the time it takes for a small cut to stop bleeding) is longer than normal. This test may be difficult to perform in young children
- The closure time (a test that measures the time it takes for a platelet plug to form in a sample of blood) is longer than normal
- Platelets appear larger than normal under a microscope
- There are usually fewer platelets than normal
- Platelets do not clump together normally in the presence of ristocetin (a substance that normally promotes platelet aggregation)
- GPIb/IX/V is not detectable in blood samples (using a test called flow cytometry)
Note: Some tests are not available in all centres.
In children, Bernard-Soulier syndrome is sometimes misdiagnosed as immune thrombocytopenic purpura, another type of bleeding problem in which there are also fewer platelets than normal.
Most people with platelet function disorders only need treatment during surgical procedures (including dental work) and after injury or accidents. When needed, Bernard-Soulier syndrome may be treated with:
- Antifibrinolytic drugs
- Recombinant factor VIIa
- Fibrin sealants
- Hormonal contraceptives (to control excessive menstrual bleeding)
- Iron replacement (if necessary to treat anemia caused by excessive or prolonged bleeding)
- Platelet transfusions (only if bleeding is severe)
People with inherited platelet function disorders should not take Aspirin®, nonsteroidal anti-inflammatory drugs (such as ibuprofen and naproxen), and blood thinners, which can make their bleeding symptoms worse.