Bernard-Soulier Syndrome

Bernard-Soulier syndrome (BSS) is a rare genetic disorder that causes issues with blood clotting. Blood clotting is your body’s process of stopping bleeding. In Bernard-Soulier syndrome, you have low platelet counts, a part of blood that’s important for clotting. If you have this condition, you must take extra precautions to avoid injuries.


What is Bernard-Soulier syndrome?

Bernard-Soulier syndrome (BSS) is a rare disorder that affects the way your blood clots. Blood clotting is the process that keeps you from excessively bleeding when you’re injured.

Platelets and plasma, two components of your blood, play important roles in forming blood clots. People with Bernard-Soulier syndrome tend to have fewer platelets than usual (thrombocytopenia). Their platelets are also bigger than usual. Because of this, people with Bernard-Soulier syndrome usually bleed and bruise easily.

How common is Bernard-Soulier syndrome?

Bernard-Soulier syndrome is rare. Experts estimate that it affects only about 1 in 1 million people worldwide.


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Symptoms and Causes

What are the symptoms of Bernard-Soulier syndrome?

Babies with Bernard-Soulier syndrome typically show symptoms early in life. People with Bernard-Soulier syndrome usually experience:

What causes Bernard-Soulier syndrome?

Bernard-Soulier syndrome is a genetic disorder, meaning you have it because of a gene change (mutation) present at birth. It’s also hereditary, meaning your parents pass down this gene mutation to you.

Bernard-Soulier syndrome occurs because of mutations in the GP1BA, GP1BB or GP9 genes. All of these genes affect how your body forms blood clots.


Diagnosis and Tests

How is Bernard-Soulier syndrome diagnosed?

Your healthcare provider uses blood tests to diagnose Bernard-Soulier syndrome. The blood tests check your platelet count and look for the gene mutations that cause Bernard-Soulier syndrome. Your provider may also look at your blood under a microscope to see if your platelets are unusually large. A test called a platelet flow cytometry measures the amount of glycoproteins 1BA, 1BB and 9 on the platelet surface.

Management and Treatment

How do you treat Bernard-Soulier syndrome?

Bernard-Soulier syndrome treatment usually focuses on preventing excessive bleeding and avoiding complications of BSS. Your healthcare provider may recommend that you:

  • Avoid medications that increase bleeding risks, such as nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin or antihistamines.
  • Brush your teeth with a soft-bristled toothbrush to lower the chances of bleeding gums.
  • Learn how to apply pressure appropriately to stop nosebleeds.
  • Limit or avoid foods and drinks such as alcohol and refined sugars that can affect your platelet count.
  • Register with a 24-hour emergency center that can treat you for emergency bleeding at any time of the day.
  • Take iron supplements if you’re iron-deficient.
  • Wear a medical alert bracelet or tag that clearly identifies your diagnosis.

Treatment for Bernard-Soulier syndrome may also include:

  • Platelet transfusions: This is typically the first-line treatment for people with BSS who have an emergency bleeding episode or are preparing for surgery. You receive donor platelets through an intravenous (IV) line in a platelet transfusion. The platelets assist with blood clotting.
  • Antifibrinolytic therapy: Antifibrinolytic agents are drugs that help your blood to clot. Your provider may give you tranexamic acid (Cyklokapron®) to control bleeding. Tranexamic acid is a type of antifibrinolytic agent.



How can I prevent Bernard-Soulier syndrome?

There’s no way to prevent Bernard-Soulier syndrome. If you have the gene mutation that causes BSS or think you may, it’s a good idea to consider genetic testing and genetic counseling. A genetic counselor can help you understand the risks and effects of passing BSS to your children.

Outlook / Prognosis

What is the outlook for Bernard-Soulier syndrome?

Most people with Bernard-Soulier syndrome can live typical lives. If you have BSS, you’ll have to take extra precautions to avoid injuries. For example, you may need to avoid participating in contact sports, which increases your risk of injuries.

You’ll also need to see your primary care provider regularly to stay in good overall health. You and your care team need to plan any elective surgeries carefully. You also may need a platelet transfusion before undergoing an operation.

Living With

What questions should I ask my doctor?

If you have Bernard-Soulier syndrome or think you could, you may also want to ask your healthcare provider:

  • What are the early signs of Bernard-Soulier syndrome?
  • What tests do I need to diagnose Bernard-Soulier syndrome?
  • What are the treatment options for Bernard-Soulier syndrome?
  • What can I do to prevent excessive bleeding if I have Bernard-Soulier syndrome?
  • What activities should I avoid if I have Bernard-Soulier syndrome?
  • What are the chances I’ll pass Bernard-Soulier syndrome to my children?

Additional Common Questions

Does Bernard-Soulier syndrome put my baby at risk if I’m pregnant?

If you’re pregnant and have BSS, you’ll need care from high-risk obstetric and hematology healthcare providers. You need careful monitoring to measure your platelet counts and overall health. You may not be able to take certain types of anesthesia that pose bleeding risks during labor.

Your newborn will need regular tests to monitor their platelet count. There’s a chance you’ll pass the gene mutation that causes BSS to your baby.

What is the main problem Bernard-Soulier syndrome causes?

Bernard-Soulier syndrome mainly causes problems with blood clotting. If you have BSS, blood clotting problems often cause excessive bleeding or easy bruising after an injury.

What conditions cause similar symptoms to Bernard-Soulier syndrome?

Several conditions may cause similar bleeding problems and symptoms as BSS, including:

A note from Cleveland Clinic

Bernard-Soulier syndrome (BSS) is a rare disorder that you inherit from your parents. If you have this condition, you’ll likely have some issues with blood clotting. But this doesn’t mean you can’t live a typical life. You may need to be careful to avoid certain activities that increase your risk of injuries that could lead to excessive bleeding. Plan to visit your primary care provider regularly. Your provider can answer any questions, help you manage your condition and work with you to maintain your overall health.


Medically Reviewed

Last reviewed on 09/02/2022.

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