Platelet function disorders
Disease Information
In-Depth
What is a platelet function disorder?
Platelets are cells that circulate in the blood stream and help the blood clot. When a child has a platelet disorder, a person’s blood may not be able to clot normally and they may develop a bleeding disorder.
Types of platelet function disorders
Acute thrombocytopenic purpura:
- most common form of idiopathic thrombocytopenia purpura
- usually occurs in children, ages 2 to 6
- symptoms may follow a viral infection, such as chickenpox
- very sudden onset, with symptoms disappearing in less than six months and often within a few weeks
- usually does not recur
- risk of serious or life-threatening bleeding is very low
Chronic thrombocytopenic purpura:
- more common in adults but can occur at any age
- affects girls two to three times more often than boys
- symptoms last a minimum of six months and can persist for many years
- may become a lifelong problem
- regular follow-up care with a blood specialist (hematologist) is recommended
What causes platelet function disorders?
In most cases, the cause of idiopathic thrombocytopenia purpura (ITP) is not known.
- Often, a child may have had a viral infection a few weeks before developing symptoms of ITP.
- Viral infections may trigger ITP, as the antibodies the body develops to fight them could be abnormal.
- Researchers have also explored the possibility that certain medications cause ITP but no direct link has been made.
- ITP is not contagious, meaning your child cannot catch it from playing with another child who has ITP.
Are platelet function disorders common?
Platelet function disorders are not extremely common. In most cases they are acquired, or caused by an external factor like another illness or medication. In rare cases they are inherited.
What are the symptoms of platelet function disorders?
The most common symptoms of platelet disorders are:
- purpura (purple color of the skin after blood has leaked under it forming a bruise, often from no known trauma)
- petechia (tiny red dots under the skin that are a result of very small bleeds into the skin)
- nosebleeds
- bleeding in the mouth and/or in and around the gums
- blood in vomit, urine or stool
- bleeding in the head (most dangerous symptom that can be life-threatening, usually prompted by a head trauma)

