Thrombocytopenia (throm-boe-sie-toe-PEE-nee-uh) is a condition in which there aren't enough platelets in your blood. Platelets (thrombocytes) are colorless blood cells that stop bleeding by clumping and forming plugs in blood vessel injuries. Depending on the cause, having low platelets may or may not result in increased bleeding risk.

The most common reason for thrombocytopenia in children is immune thrombocytopenia (ITP). This occurs when the immune system mistakenly attacks and destroys platelets. Children who develop ITP often have a history of a recent viral infection. Most children recover from ITP without any treatment within six months. Until then, they may need to avoid contact sports or other activities that could result in head injuries.

Less-common causes of thrombocytopenia in children include bone marrow disorders such as leukemia or other autoimmune conditions such as systemic lupus erythematosus (SLE) or hereditary bone marrow disorders.


Some children who have thrombocytopenia never experience bleeding symptoms. For those who do have symptoms, they may include:

  • Easy bruising
  • A sprinkling of small purplish spots on the skin (called petechiae or purpura)
  • Nosebleeds
  • Bleeding from the gums
  • Prolonged bleeding from minor cuts

Children who have mild cases of thrombocytopenia may have no symptoms at all.


Children can develop thrombocytopenia if the bone marrow doesn't make enough platelets, the body destroys too many platelets or the spleen retains too many platelets.

These problems can result from:

  • Diseases affecting the immune system
  • Infections
  • Hereditary disorders
  • Exposure to certain medications or toxins
  • Cancers such as leukemia or lymphoma

Pediatric thrombocytopenia care at Mayo Clinic

July 02, 2020
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  2. Kliegman RM, et al. Platelet and blood vessel disorders. In: Nelson Textbook of Pediatrics. 21st ed. Elsevier; 2020. https://www.clinicalkey.com. Accessed April 27, 2020.
  3. Despotovic JM. Approach to the child with unexplained thrombocytopenia. https://www.uptodate.com/contents/search. Accessed April 27, 2020.
  4. Pruthi RK (expert opinion). Mayo Clinic. June 3, 2020.