For US Residents Only.

Understanding the Disease

Chronic ITP in Children

Understanding the Disease Understanding the Disease

What is Chronic ITP in children?

Chronic immune (idiopathic) thrombocytopenia (ITP) is a blood disorder in which there is an abnormal decrease in the number of platelets in the blood. Platelets are cells in the blood that help stop bleeding. A decrease in platelets can lead to bruising, bleeding gums, and internal bleeding.


  • Chronic ITP is ITP that has lasted 6 months or longer and requires continual follow-up care with a doctor who specializes in blood diseases (hematologist)
  • “Idiopathic” means that the cause is unknown
  • “Thrombocytopenia” means a decreased number of platelets in the blood


As a parent or caregiver of a child with chronic ITP, you might be well aware of the challenges associated with an unpredictable disease that can change from day to day. Chronic ITP can limit certain activities and affect how active your child can be.

Why are platelets important?

How blood clots

Platelets are cells that are made in the bone marrow and circulate in the blood.

Platelets stick together to help form blood clots. Blood clots help prevent bleeding and bruising when your child gets a cut or wound. In a child with chronic ITP, there are not enough platelets, and blood clots do not form properly. When your child’s platelet count is low, he or she may have bruising and/or bleeding that is hard to stop.

What makes your child’s platelet levels low?

In chronic ITP, the way your child’s body controls the number of platelets in circulation is out of balance. There are 3 ways that this can happen:


  1. Platelets are destroyed. Your child’s immune system thinks platelets are cells that will hurt the body, so it attacks them.
  2. Platelets are trapped in the spleen. The spleen is an organ that removes old and damaged platelets and red blood cells from blood circulation. Platelets that are attacked by the immune system are removed from the blood and trapped in the spleen.
  3. Fewer platelets are made. In children with chronic ITP, there usually is not enough thrombopoietin (TPO) reaching the bone marrow. TPO is a protein produced primarily in the liver that controls how many platelets are made. This means that there are not enough platelets being made to replace destroyed platelets.
How platelets circulate How platelets circulate

The goal of chronic ITP treatment is to help increase platelet counts to target levels

A number of treatment options are available to help raise platelet counts in patients with chronic ITP.




Immunosuppressants are agents that slow down the immune system. Medications like corticosteroids and intravenous immunoglobulin (IVIG) are immunosuppressants that decrease the number of platelets being destroyed.


 TPOr agonists


TPO-receptor agonists

Thrombopoietin receptor agonists, or TPO-receptor agonists for short, are medicines that work by sending signals to the body to make more platelets.





Splenectomy is the surgical removal of the spleen. In chronic ITP, platelets are removed from the blood and trapped in the spleen. By removing the spleen, more platelets remain in the blood circulation.