My child is five years old and has a low platelet count. What could be the cause and treatment?

Doc needed. Many causes of low platelet count. First let's just make sure by using another lab. Please consult with a hematologist. Tomorrow. This is just too important!
Varies. This can be lab error, something is preventing their creation or something is consuming them too fast. Platelets can sometimes clump together & confuse the lab equipment, causing a false low number. A very nasty illness can stop their creation. Other illnesses can consume or use up platelets so fast their numbers drop.Treatment is based on verifying the condition & identifying the cause.
Many. There are many causes for a low platelet count. Some can be serious but most are not. Probably the most common is caused by a virus and will resolve on its own but i would see a hematology doctor to decide if any further work up needs to be done.