Immune Thrombocytopenia (ITP)

What is immune thrombocytopenia (ITP)?

Immune thrombocytopenia (ITP) is an autoimmune disorder that causes low numbers of platelets. Platelets are blood cells that help stop bleeding. ITP can cause easy bruising and bleeding.

ITP can develop suddenly. In most cases, platelet numbers return to normal over weeks or months. However, counts can vary for some time.

Most children recover from ITP within the first 6 months after diagnosis. ITP that lasts 12 months or longer is called chronic immune thrombocytopenia (chronic ITP).

What are platelets?

Platelets are blood cells that help stop bleeding. When there is a cut or injury, platelets come together to form a clot or “plug” to stop the bleeding. If the body does not have enough platelets, a clot cannot form. This may cause abnormal bruising or bleeding.

A normal platelet count is 150,000/mm³ to 400,000/mm³. Serious bleeding can occur when the platelet count is less than 10,000/mm3.

Causes of ITP

ITP is a disease of the immune system. In most cases, the cause of ITP is not known. In children with ITP, the body makes platelets normally, but the immune system attacks and destroys them by mistake.

ITP often occurs after a viral infection. The body makes antibodies to fight against an infection. In children with ITP, the body also makes antibodies that fight against the body’s own platelets. ITP is not contagious.

ITP often affects healthy children. Sometimes, it may develop in patients with other autoimmune conditions or problems with the immune system.

Symptoms of ITP

ITP can cause unusual bleeding because of low platelets. Signs and symptoms of ITP include:

• Petechiae - small, red or purple “pinpoint” dots on the skin that may look like a rash
• Bruising or purplish areas on the skin, lips, or inside the mouth
• Bleeding that lasts longer than normal
• Bleeding from the nose or gums
• Blood in urine or stool
• Heavy menstrual cycles or periods

Tests for ITP

ITP is diagnosed based on your child’s medical history, physical exam, and lab tests. Your doctor may ask you about any changes in bleeding or bruising, recent illnesses, or medicines your child is taking.

Lab tests may include:

• Complete blood count (CBC) measures the number and size of the platelets and other blood cells.
• Blood smear is a blood test that uses a microscope to check the shape and size of platelets and other blood cells.
• Urine and stool tests can check for blood in the urine or stool.
• Other blood tests can look for other possible causes of low platelets.
• Bone marrow testing can make sure that platelets are being made normally.
• Genetic testing can check for inherited disorders or gene changes that cause low platelets in children with chronic ITP.

Treatments for ITP

Not all children need treatment for ITP. Many children recover on their own. Your care team may recommend watchful waiting. The hematology team will check your child’s blood counts and symptoms to see when and if treatment is needed.

Your doctor may prescribe medicines to help manage ITP.

Medicines for ITP include:

• Corticosteroids such as prednisone can be given in a pill or liquid form to slow the destruction of platelets.
• Intravenous immune globulin (IVIG) or WinRho® are given by intravenous (IV) infusion into a vein. These medicines slow down the destruction of platelets.
• Rituximab (Rituxan®) is a medicine given by IV that works to reduce the antibodies that attack platelets.
• Some medicines help the body make more platelets. These include eltrombopag (Promacta®) given by mouth and romiplostim (Nplate®) given by injection.
• Other medications may be used to suppress the immune system.

General medicines for bleeding symptoms include:

• Aminocaproic acid (Amicar®) can be used for mouth or nose bleeds or heavy menstrual bleeding.
• Hormone therapy may be used to help control heavy periods in girls.

Your doctor may recommend surgery to remove the spleen (splenectomy) if other treatments do not work. Removing the spleen can help some children with chronic ITP who have very low platelets.

Platelet transfusions may be given if there is life-threatening bleeding or before a surgery or a procedure. In a platelet transfusion, donor platelets are given into a vein by IV.

Living with ITP 

Know what activities to avoid. Children with ITP can do most usual daily activities. Having ITP should not stop your child from having fun. However, talk to your doctor about any activity that might be harmful.

When platelet counts are low, your child should avoid contact sports, rough play, and activities that could involve falls or injury to the head or stomach.

Take steps to keep your child safe. Be sure your child wears a seatbelt and uses recommended safety equipment such as a helmet, knee pads, elbow pads, and wrist pads during approved sports or activities.

Alert others of your child’s condition. Your child should tell an adult if they fall or hit their head. Be sure that others know about your child’s medical condition and know what to do if an accident occurs.

Do not give your child aspirin or ibuprofen (Motrin®, Advil®). These medicines can keep platelets from working properly. If needed, give acetaminophen (Tylenol®) for headache, pain, or fever.

When to call your doctor 

Most children with ITP do very well. Watch for signs and symptoms of low platelets or bleeding. Tell your doctor right away if your child has any of these symptoms:

• Petechiae, bruising, or purplish areas on the skin or in the mouth
• Gums that bleed easily
• Nosebleeds
• Blood in the urine or stool
• Headache that won’t go away or gets worse, especially after a fall or accident

The main risk of ITP is severe bleeding. Very rarely, children with ITP may have serious internal bleeding.

Call your doctor or go to an emergency room right away if your child has any serious injury, especially one that involves any hit to the head or stomach.