What is idiopathic thrombocytopenic purpura (ITP)?
Idiopathic thrombocytopenic purpura (ITP) is a bleeding disorder. “Idiopathic” means the cause of the condition is unknown. “Thrombocytopenic” means the blood doesn’t have enough platelets. (Platelets are also called thrombocytes.) “Purpura” means a person has excessive bruising.
When you have ITP, your immune system destroys the platelets in your blood. Platelets are the tiny cells that form blood clots. They seal minor cuts and wounds. A person who doesn’t have enough platelets bruises very easily. They can bleed for a long time after being injured. A person who has ITP might have nosebleeds that are hard to stop. Rarely, they might have bleeding in the intestines, or even bleeding in the brain with minor trauma.
ITP is also sometimes called “immune thrombocytopenic purpura” or “immune thrombocytopenia.” It can happen in adults or children. In children, the condition usually resolves on its own without treatment. For adults, it is often a long-term condition.
Symptoms of ITP
The symptoms of ITP include:
- Easy or excessive bruising.
- Tiny reddish purple dots on the body, especially on the lower legs. Called petechial rash, this is caused by bleeding under the surface of the skin.
- Cuts or minor wounds that take a very long time to clot or stop bleeding.
- Blood in the urine or stools.
- Unusually heavy menstrual flow in women.
- Unexplained bleeding from the nose or gums.
In most adults, ITP lasts much longer than it does in children. At the time of diagnosis, many adults have noticed symptoms for several weeks or months. At the same time, many adults have only mild thrombocytopenia. Some have no bleeding symptoms at all.
What causes ITP?
The cause of ITP is not known. People who have ITP form antibodies that destroy their blood platelets. Normally, antibodies are a healthy response. They attack and destroy bacteria or viruses. But in people who have ITP, the antibodies attack the body’s own cells. Doctor’s aren’t sure exactly why this happens.
Who gets ITP?
There are 2 types of ITP—acute (short-term) and chronic (long-term). Acute ITP mainly affects children. They often get the condition after a viral illness, such as the flu. The usual age for a child getting ITP is 2 to 4 years of age. Chronic ITP typically affects adults. Most adults with ITP are young women, but it can occur in anyone. ITP does not seem to be hereditary (run in families). ITP is not contagious (you can’t “catch it” from someone else).
How is ITP diagnosed?
Your doctor will ask you questions about your health. He or she will do a physical exam. They may take a blood sample for testing. The test counts blood cells and platelets. Or they may look at the sample under a microscope. Your doctor may also want you to get a bone marrow exam. This can help rule out other possible causes of your symptoms.
Many adults find out they have ITP by accident. Their blood is checked for another reason and a low blood platelet count is found.
Can ITP be prevented or avoided?
Since there is no known cause, there is nothing that can prevent or avoid the condition.
ITP treatment
Mild cases of ITP may not require treatment, just regular monitoring of platelet levels. More serious cases will require treatment.
Treatment of ITP in adults does not cure the disease. It is aimed at increasing the blood platelet count. Your doctor may recommend that you take prednisone for several weeks or months. Prednisone is a steroid that raises the level of your platelet count. As your count rises and reaches a safe level, your doctor may gradually decrease your medicine. However, when the medicine is stopped, your platelet count may decrease again.
Other treatments for ITP include other medicines. These include:
- Another kind of steroid called danazol.
- Medicines that suppress the immune system.
- Infusions of high-dose gamma globulin.
- Anti-RhD therapy for people with certain blood types.
If medicines don’t help enough, your doctor may recommend that your spleen be removed. The spleen makes most of the antibodies that destroy the blood platelets. It also destroys old or damaged blood cells. But removing the spleen permanently reduces your body’s ability to fight infection. Some people can have the ITP come back even after the spleen is removed. So this treatment is not done as often as it used to be.
How is ITP treated in children?
ITP in children is usually mild. It runs its course without the need for treatment. About 80% of children recover completely from ITP within about 6 months. When a child is diagnosed, many doctors recommend just watching the child carefully. However, some doctors recommend a short treatment with prednisone pills or gamma globulin infusions. These treatments will increase the platelet count more quickly. Both medicines have some side effects.
Living with ITP
If you have ITP, you should avoid medicines that increase risks for bleeding. Some of these include warfarin, aspirin, or ibuprofen (Advil, Motrin). You should also limit alcohol. It can decrease the ability of your blood to clot.
What about ITP in pregnant women?
Many of the medicines used to treat ITP should not be taken by women who are pregnant. Talk to your doctor if you are taking medicine for ITP and want to become pregnant.
Diagnosing ITP during pregnancy can be difficult. Platelet counts may be low for other reasons. About 5% of women have mildly low platelet counts at the end of a normal pregnancy. The cause of this is unknown. The platelet count goes back to normal right after delivery.
A baby born to a mother who has ITP may have a low blood platelet count a few days to a few weeks after birth. These babies usually are kept in the hospital for several days. That way, doctors can make sure they are okay before sending them home. If the baby’s platelet count is very low, treatment is available to speed recovery.
Questions to ask your doctor
- I bruise easily. Do I have idiopathic thrombocytopenic purpura (ITP)?
- What are some other symptoms of idiopathic thrombocytopenic purpura?
- Did I inherit ITP? Can I pass it on to my children?
- How is ITP treated?
- What are the side effects of prednisone?
- What can I do to reduce the symptoms of ITP?
Copyright © American Academy of Family Physicians
This information provides a general overview and may not apply to everyone. Talk to your family doctor to find out if this information applies to you and to get more information on this subject.
