Platelet Disorders (Pediatric)
What are platelets?
Platelets are a part of the blood whose main job is to stop bleeding by clumping together and plugging up injuries to blood vessels, such as from a cut. Excessive bleeding that starts without any known cause and does not stop in a normal amount of time may indicate that something is wrong with the body’s platelets.
Abnormal bleeding due to platelet disorders can be caused by having not enough platelets, platelets that are not functioning correctly, or having too many platelets. The normal number of platelets in the blood is 150,000 to 400,000 per cubic millimeter.
- A low platelet count is called thrombocytopenia, and is caused by the body either not making enough platelets, or by a disorder that causes a large number of platelets to be destroyed by the body’s immune system. Thrombocytopenia can also be caused by certain drugs, or by a mismatch between platelets in a newborn from those of its mother.
- A high platelet count is thrombocytosis, which is either passed along from birth, or is caused by a condition, such as a cancerous condition, that keeps the body from controlling how many platelets it makes.
- If the platelets are simply not working correctly, that is called thrombocytopathy. Abnormal platelet function can sometimes exist from birth, but is frequently caused by medication such as aspirin and anti-inflammatory drugs.
Platelet bleeding is defined by bleeding into the skin which causes a purplish stain referred to by its size: petechiae (small red or purple dots on the skin), purpura (mediam-sized spots on the skin), ecchymoses (larger areas of discoloration or bruising). Bleeding may happen in other parts of the body, such as mucous membranes, gums, nose bleeds, and the gastrointestinal tract.
Our approach to platelet disorders
The most common child and adolescent platelet disorder is immune thrombocytopenia (ITP, also called idiopathic thrombocytopenia). ITP is a condition in which the immune system attacks the platelets. The symptoms include small or medium sized spots (petechiae and purpura) showing where bleeding has happened.
In mild cases of ITP, no treatment may be needed other than careful observation by a health care provider. However, if platelet counts get very low or bleeding is significant, your health care provider may begin immediate treatment with corticosteroids, intravenous immunoglobulin or anti-D immunoglobulin (both of which affect the immune system and how it interacts with platelets), or immunosuppressive drugs that make the immune system less likely to attack.
If these treatments are not able to control ITP, the health care provider may recommend, splenectomy, which is the surgical removal of the spleen.