Platelets are very small cells that are an important part of the clotting process to stop bleeding. When a blood vessel is damaged, platelets along with von Willebrand factor go to the damaged area to form a plug to stop the bleeding. When the platelets are actively forming a blood clot, they send out a chemical that calls for other platelets to help form a plug.
- The normal amount of platelets in a person’s body is between 150,000 and 350,000.
- When a child has less than the normal amount of platelets, they have a platelet disorder called thrombocytopenia, and it is important that consultation with a hematologist be done to figure out why the platelet number is low.
- Sometimes, a patient can have a normal number of platelets, but the platelets don’t work well - these are called platelet function disorders or sometimes just platelet disorders.
Platelet Function Disorders
Adhesion Disorders
An adhesion disorder is the result of the platelets not being able to stick to the wall of the damaged blood vessel to form a plug and stop the bleeding.
Bernard-Soulier Syndrome
Bernard-Soulier Syndrome is a rare disorder that is inherited or passed down from a child’s parent(s). A child with Bernard-Soulier Syndrome has platelets that are large and missing a chemical that helps the platelets stick to the wall of a damaged blood vessel.
Symptoms with this disorder range from mild to severe:
- Bleeding that does not stop for 10 to 20 minutes
- Mouth, dental or nose bleeding
- Bleeding for a long time after surgery or an injury
- Gastro-intestinal bleeding
- Blood in vomit or stool
- Women may have heavy menstrual periods or bleeding after child birth
Treatment:
- Avoid aspirin or medicines affecting platelet function
- Avoid activities or sports where there is a higher risk of injury
- Tell other health care providers that you or your child has a platelet disorder
- Girls or women may need hormonal therapy to control their heavy periods
- Epistaxis care for a nosebleed
- Stimate (intranasal DDAVP) may be used in certain platelet disorders
Aggregation Disorders
An aggregation disorder is when platelets do not bind with fibrinogen and other proteins in order to stick to other platelets. As a result the platelets cannot form a plug to stop the bleeding from a damaged blood vessel.
Glanzmann’s Thromboasthenia
Glanzmann’s Thromboasthenia is a disorder that is inherited or passed down from a child's parent(s). This disorder causes moderate to severe bleeding symptoms:
- Bleeding from the mouth
- Bleeding with dental procedures
- Nose bleeds
- Bruising or small purplish red dots under the skin
- Bleeding for a long time after an injury or surgery
- Girls or women may have heavy periods
- Infant boys may have bleeding after circumcision
Other Aggregation Disorders
People who have other aggregation disorders have a low amount or are missing chemicals needed to help platelets stick together. If the platelets cannot stick together, then they cannot form a plug to stop the bleeding from a damaged blood vessel.
Treatment:
- Avoid aspirin or medications affecting platelet function
- Avoid activities or sports where there is a higher risk of injury
- Tell other health care providers that you or your child has a platelet disorder
- Girls or women may need hormonal therapy to control their heavy periods
- Epistaxis care for a nosebleed
- Stimate (intranasal DDAVP) may be used in certain platelet disorders
Secretion Disorders
A secretion disorder is when the damaged blood vessel takes more time for the bleeding to stop due to missing chemicals that signals the platelets to stick together. As a result, it takes a lot longer for the bleeding from a damaged blood vessel to stop. This is the most common platelet disorder.
Diagnosis and Treatment:
All of these disorders require specialists in bleeding disorders to diagnose them. The diagnosis is made by specialized blood tests that can be performed at Children's Hospital Los Angeles. Treatment can be done at home for most bleeding events with special medications. If your child displays symptoms of a platelet disorder, please contact our clinic for an appointment.