Patient education: Immune thrombocytopenia (ITP) (The Basics)

What is immune thrombocytopenia? — Immune thrombocytopenia (ITP) is a disorder of the platelets. Platelets are blood cells that help blood to clot.

People with ITP have a lower than normal number of platelets because their immune system destroys their platelets. The immune system is the body's infection-fighting system. Doctors call a low platelet count "thrombocytopenia." Immune thrombocytopenia means it is caused by your immune system.

Some people with ITP can bruise or bleed much more easily than normal.

ITP can happen in adults and children. In children, it sometimes happens after an infection. Often it gets better on its own in children. If an adult has a very low platelet count, they might need medicines to block the immune system so it stops destroying platelets.

What are the symptoms of ITP? — Some people with ITP have no symptoms. When people do have symptoms, they can:

●Bleed easily – This can include nosebleeds or blood-filled blisters inside the mouth. In females, monthly periods can be very heavy. Sometimes, there can be more serious bleeding, like bleeding in the brain or inside the body.

●Bleeding under the skin – This could look like large bruises or tiny bruise-like dots on the feet and ankles.

Is there a test for ITP? — Partly. There is a test for the number of platelets in the blood, called the "platelet count." This is often done as part of a "complete blood count" (or "CBC"). If your platelet count is low, ITP might be the cause. But there is no test that can tell for sure if the low platelet count is because of ITP or something else.

If a blood test shows that a person has a low platelet count, you will be asked about symptoms, have an exam, and have some blood tests. This is to help figure out if another condition is causing the low platelet count. The main test is called the "complete blood count." It tells if the white blood cell count is also low, and if you have a condition called anemia. White blood cells are infection-fighting cells.

In children, ITP is a common cause of a low platelet count. A child might get better on their own. Adults might have tests for other causes of a low platelet count. If no other cause of a low platelet count is found, then the diagnosis might be ITP. Some of the other tests might include:

●Lab tests to check for infections, measure vitamin levels, or test for other blood disorders

●Bone marrow test – This might be done in older adults. The bone marrow is the cells inside some of your bones. It makes all of the blood cells, including platelets. A bone marrow test is a procedure that involves numbing the hip bone and using a needle to take a tiny sample. Then the sample is examined under a microscope.

How is ITP treated? — Treatment for ITP depends on the person's age, symptoms, and how low the platelet count is.

Children with ITP do not need treatment unless they have a lot of bleeding or a very low platelet count. For most children, ITP goes away on its own within 6 months. But doctors follow children with ITP closely to make sure the ITP does not get worse or end up needing treatment.

Adults with a very low platelet count or bleeding will most likely need treatment. If the ITP is mild and there is no bleeding, treatment is usually not needed.

Adults who need treatment are first treated with a steroid medicine. Steroids block the immune system and stop it from destroying platelets. Steroids have some side effects that you will need to know about. Your doctor will talk to you more about this.

Steroids can take several days to work. People who need a very fast increase in platelet count might be treated with a platelet transfusion (when you get platelets donated by someone else) or a medicine called intravenous immune globulin (or "IVIG"). IVIG stops the body from destroying platelets.

If the ITP doesn't get better, there are other treatments. These include:

●Surgery to remove the spleen – The spleen is part of the body's immune system (figure 1). Removing the spleen often stops the immune system from destroying platelets.

●Other medicines that block the immune system, such as rituximab. This is given through a thin tube that goes into a vein, called an "IV."

●Medicines that help the body make more platelets.

If these treatments don't work, other treatments are available.

What else might people with ITP need to do? — Depending on their platelet count and symptoms, people with ITP might need to:

●Avoid certain sports or activities – If your platelet count is very low, it's important to limit physical activity and not play certain sports, especially contact sports. That's because accidents can cause bleeding. If a person with a very low platelet count gets hurt, they can have even more serious bleeding. People can do their usual sports and activities again when their platelet count gets to a safe level.

●Avoid taking certain medicines – Some medicines, such as aspirin and drugs called non-steroidal anti-inflammatory drugs (or "NSAIDs"), make your platelets not work as well. This can make bleeding more likely. Drugs that thin your blood, or "anticoagulants," also increase your risk of bleeding. Your doctor or nurse will let you know which prescription and over-the-counter medicines to avoid.

What if I have ITP and want to get pregnant? — If you have ITP and want to get pregnant, discuss this with your doctor or nurse.

Most people with ITP can have a normal pregnancy and delivery. But you might need to be watched more closely or take certain medicines, especially around the time of delivery.

Your baby's platelet count might need to be tested as well. This is because there is a small chance your baby could also have a low platelet count for a short time after birth. This does not mean the baby has ITP, but it is important to check the baby's platelet count.

More on this topic

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