Glanzmann thrombasthenia

What happens in this disease?

Platelets are tiny blood cells that stick to each other to stop bleeding. To do this, they have a special receptor protein on their surface. In this disease, that protein is missing or faulty. The platelet count is usually normal, but the cells cannot clump together. This is why bleeding lasts a long time.

Which symptoms can occur?

How severe the bleeding is varies greatly from person to person, even within the same family. Spontaneous bleeding tends to decrease with age.

• Easy bruising
• Frequent nosebleeds
• Bleeding gums
• Red or purple spots on the skin
• Prolonged bleeding after a wound, surgery or dental treatment
• Heavy and long menstrual periods
• Bleeding in the stomach and gut (in about a quarter)
• Bleeding inside the head or into the joints (rare)

How is it diagnosed?

The platelet count is usually normal, but the bleeding time is long. Platelet clumping tests give abnormal results. The definite diagnosis is made with a special blood test that shows the receptor protein is missing. A genetic test can find the gene change that causes the disease.

Treatment and care

Platelet transfusions are given when there is bleeding or before surgery. Medicines that stop a clot from breaking down too early are also used. If platelet transfusions do not work, an approved clotting factor treatment can be given. Hormone treatment helps with heavy menstrual bleeding. Regular dental care is important. Some people with severe disease have been cured with a stem cell transplant. The doctor who follows the disease decides which treatment is suitable.

For the family: inheritance and genetic counselling

The disease is passed on through recessive inheritance. The mother and father are carriers but usually have no symptoms. For a couple who are both carriers, the chance of having an affected child is 1 in 4 in each pregnancy. Girls and boys are affected equally. Recessive diseases may be more common in marriages between relatives. In genetic counselling, carrier testing and prenatal testing can be discussed.