Glanzmann Thrombasthenia

What is Glanzmann thrombasthenia?

Glanzmann thrombasthenia (GT) is a chronic (lifelong) condition that causes you to bruise and bleed easily. It involves a problem with your platelets, the tiny blood cells that help your blood clot.

If you have GT, a genetic mutation prevents your body from making a key protein your platelets need to form clots. As a result, clots form more slowly, causing you to bleed more. The severity of the blood loss varies from person to person. Bleeding may be so mild you can manage it at home or so severe you need emergency care.

How common is Glanzmann thrombasthenia?

Glanzmann thrombasthenia is rare. Medical experts estimate that only about 1 in 1 million people worldwide are born with GT.

That number is closer to 1 in every 200,000 people in communities where the gene mutation tends to run in families. Babies are more likely to be born with GT in certain countries in the Middle East, the Canadian provinces of Newfoundland and Labrador, and the Romani community in France.

What are the symptoms of Glanzmann thrombasthenia?

If you have GT, you may bleed more if you’re injured than another person would with a similar injury. Or, your bleeding may start unexpectedly — for no clear reason at all

Glanzmann thrombasthenia symptoms include:

• Bruising easily.
• Bleeding gums.
• Frequent nosebleeds (epistaxis).
• Purple spots or patches on your skin (purpura).
• Purple, brown or red dots on your skin (petechiae).
• Heavy menstrual bleeding (menorrhagia).

With GT, internal bleeding is much less common than bleeding from your skin (after an injury, like a cut) or your mucous membranes (like the lining of your nose and mouth).

What causes Glanzmann thrombasthenia?

Babies born with Glanzmann thrombasthenia inherit a mutation (or error) in the genes that control the production of integrin alpha IIb/beta 3 — a protein that helps platelets clot. To develop GT, you inherit a mutated gene from both parents. This type of inheritance is called autosomal recessive.

Most parents don’t realize they carry the mutation because it takes two copies of the mutated gene to cause symptoms. Carriers have one normal gene and one mutated gene.

If both parents are carriers, they have a 25% chance of having a child with GT.

Acquired Glanzmann thrombasthenia

Some people acquire GT later in life. But this is incredibly rare. Although it can happen, medical experts still classify Glanzmann thrombasthenia as an inherited bleeding disorder.

With acquired GT, your body makes antibodies that attack integrin alpha IIb/beta 3. Many conditions and even some medications can potentially trigger this response. But the results are the same. Without enough functioning protein, your platelets take longer to form clots.

What are the complications of Glanzmann thrombasthenia?

Heavy period bleeding can lead to iron-deficiency anemia. In severe cases, GT can lead to serious (and even life-threatening) hemorrhaging during major life events where blood loss is common, like childbirth and surgery.

Your healthcare provider can take steps to prevent these complications if you’re diagnosed with GT.

How is Glanzmann thrombasthenia diagnosed?

Healthcare providers perform tests to diagnose GT. This usually happens in childhood. As a parent, you may take your child to see a provider because they bruise easily or get frequent, prolonged nosebleeds. You may notice heavy or ongoing bleeding during a major life event, like when your child:

• Gets circumcised.
• Loses their first baby tooth.
• Gets their first period (menarche).

More than 80% of people with Glanzmann thrombasthenia get diagnosed before age 14. Most get diagnosed before they turn 5. Adults diagnosed with GT may not realize there’s an issue until they experience trauma, like an injury or accident.

What tests will be done to diagnose GT?

Healthcare providers use blood tests to diagnose Glanzmann thrombasthenia. Tests can show problems with:

• Your platelets: A complete blood count (CBC) can show if you have a normal number of platelets. A peripheral blood smear can show whether they look unusual.
• How your blood clots: Several tests, including a prothrombin time (PT) test and a partial thromboplastin time (PTT) test can show how quickly and effectively your blood clots. They can help providers rule out more common bleeding disorders that can be mistaken for GT, like von Willebrand disease or Bernard-Soulier syndrome.
• Integrin alpha llb/beta3: Tests like flow cytometry and monoclonal antibody panels can show if you have too little (or defective) integrin alpha llb/beta3. They can also detect antibodies that may attack this protein.
• Your genes: Genetic tests can determine whether you have the mutations in the genes that cause GT. These genes are ITGA2B and ITGB3.

How is Glanzmann thrombasthenia treated?

If you’re diagnosed with GT, your healthcare provider will advise you on how to reduce your risk of bleeding. You’ll likely work with a blood disorders specialist called a hematologist. Outside of prevention, treatment depends on how severe your bleeding is.

Mild to moderate bleeding

Treatments for mild to moderate bleeding include:

• Compression: Your healthcare provider can teach you how to apply pressure to slow blood flow from a wound or stop a minor nosebleed. For a serious nosebleed, your provider may insert a material like gauze or foam into your nose to stop the bleeding (nasal packing).
• Medications: You may need medication to help your blood clot, like fibrin sealant (glue), gelatin foam, topical thrombin and antifibrinolytic agents.

Severe bleeding

Severe bleeding with Glanzmann thrombasthenia requires emergency care. Treatments include:

• Platelet transfusions: You may need a platelet transfusion to stop severe blood loss or to prevent blood loss before a major procedure or childbirth. During a transfusion, you receive healthy platelets from a donor.
• Red blood cell transfusion: If you’ve already lost too much blood, you may need a red blood cell transfusion to rebuild your stores.
• Recombinant coagulation factor VIIa (rFVIIa): You may need this medication if you’re not a candidate for a platelet transfusion.
• Hematopoietic stem cell transplant: A stem cell transplant is the only potential cure for GT. It may be an option in severe cases of GT where no other methods have worked. During this procedure, a provider injects stem cells from a donor into your body.

Complications of Glanzmann thrombasthenia treatment

About 20% to 30% of people who receive platelet transfusions eventually develop antibodies against them. This means that the added platelets don’t actually help. When this happens, you’ll need an alternative treatment, like injections of rFVIIa. But this medicine comes with some risks. For example, it may cause your blood to clot too much.

Stem cell transplants can cure Glanzmann thrombasthenia, but it can be challenging to find a donor match whose stem cells will work for your body. Most donors in stem cell transplants for GT have been siblings. Even with a matched donor, there’s a risk that your body will reject the donated stem cells. This condition is called graft versus host disease (GvHD).

Your healthcare provider will discuss the risks and benefits of your treatment options beforehand.

What can I expect if I have GT?

No two people with Glanzmann thrombasthenia experience the condition the same way, even if they’re in the same families and have the same mutation. How much bleeding you have and the steps needed to manage your condition depend on your situation.

The good news is that with management, most people with Glanzmann thrombasthenia go on to live normal lives with a normal life expectancy. In some cases, the amount of bleeding decreases as people age.

How do I take care of myself?

If you have GT, work with your healthcare provider to reduce your risk of bleeding and severe blood loss. You should:

• Know which medications to avoid. Steer clear of blood thinners (like aspirin and other NSAIDs) and other medications that your provider tells you to avoid.
• Take good care of your oral health. Brushing and flossing daily and seeing a dentist for regular checkups reduce your risk of bleeding gums.
• Take good care of your nose. Keeping the lining of your nose moist can reduce your risk of nosebleeds. You can use a humidifier, a nasal spray, or rub Vaseline on the inside of your nose to prevent it from becoming too dry.
• Manage heavy menstrual bleeding. Using hormonal forms of birth control can prevent heavy periods.
• Wear a medic alert bracelet. Always have identification on you that lets emergency workers know you have a bleeding disorder. It could save your life in a high-stakes medical situation.
• Have a plan for bleeding episodes. Know when you should care for yourself at home when you’re bleeding versus when you need to see a provider ASAP. Make sure you know who to contact and where to go, so there are no delays in getting care.

When should I see my healthcare provider?

Schedule a visit with your provider if you or your child is showing signs of easy bleeding. Bruises and nosebleeds are common. But if the symptoms are frequent and it takes a long time for the blood flow to stop — contact a provider.

When should I go to the ER?

If you’re experiencing blood loss that won’t stop, including heavy menstrual bleeding, skip scheduling an appointment and visit the ER instead. Signs to look out for include:

• A nosebleed that lasts an hour.
• Bleeding through two or more tampons or pads each hour for two or more hours.

What questions should I ask my healthcare provider?

Questions to ask include:

• What tests will I need to diagnose my condition?
• What treatments will I need?
• What lifestyle changes can I make to manage my condition?
• What are the chances that I’ll pass GT on to a child?
• Do you recommend genetic testing if I decide to become pregnant?

Do people with GT have a normal platelet count?

Usually, the platelet count is normal with Glanzmann thrombasthenia. The problem isn’t with the number of platelets. Instead, platelets can’t clot as effectively because there’s a problem with the protein that allows them to bind with other platelets.

What is the difference between Glanzmann thrombasthenia and Bernard-Soulier syndrome?

Glanzmann thrombasthenia and Bernard-Soulier syndrome (BSS) are both rare genetic disorders involving problems with how your blood clots. But they involve different genetic mutations. The specific problems with platelets are different, too. People with BSS tend to have fewer, abnormally large platelets.

A note from Cleveland Clinic

Glanzmann thrombasthenia is a lifelong condition that you and your hematologist will need to keep tabs on. With GT, there’s no way to predict how severe (or mild) your bleeding will be. Regardless, taking steps to reduce your risk of bleeding episodes can help keep you in good health. So can platelet transfusions if your GT is severe. You may not have control over whether you’re born with this condition. But you do have options when it comes to managing it so it doesn’t interfere with your quality of life.