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

Blood tests can confirm the diagnosis and may provide clues to underlying conditions causing the problem. Rarely, your doctor might suggest a bone marrow biopsy.

Treatment depends on the cause of your child's thrombocytopenia. In some cases, treatment might not be necessary. Thrombocytopenia may improve if an underlying cause is identified and treated. Treatment for thrombocytopenia may include medications, such as corticosteroids, gamma globulin or immune-suppressing drugs, and blood or platelet transfusions.

You'll likely first bring your child's symptoms to the attention of your family doctor. Depending on your symptoms, you may be referred to a specialist in blood diseases (hematology).

Consider taking a relative or friend along to the appointment to help remember all the information provided.

Here's some information to help you get ready for the appointment, and what to expect from the doctor.

What you can do

Before your appointment, make a list of:

• Signs and symptoms, including any that seem unrelated to the reason for the appointment
• Any medications, including vitamins, herbs and over-the-counter medicines that your child is taking, and their dosages
• Key personal information, including any major stresses or recent changes in your child's life

For pediatric thrombocytopenia, some basic questions to ask the doctor include:

• Will my child need additional tests?
• What are the treatment options?
• What are the benefits and risks of each treatment?
• Are there brochures or other printed material that I can have? What websites do you recommend?

What to expect from your doctor

The doctor is likely to ask you several questions. Be ready to answer them to allow time later to cover other points you want to address. Examples include:

• When did your child first begin experiencing symptoms?
• How severe are the symptoms?
• What, if anything, seems to improve your symptoms?
• What, if anything, appears to worsen the symptoms?
• Has anyone in your family ever had similar symptoms?
• Has your child traveled out of the country lately?
• Has your child had a viral infection within the past month?