An Overview of Idiopathic Thrombocytopenic Purpura (ITP)

A blood disease that causes bleeding and bruising

Idiopathic thrombocytopenic purpura (ITP), also called immune thrombocytopenic purpura, is a condition in which the body does not have enough platelets. This condition is characterized by purpura, which are purple looking bruises on the skin.

ITP is considered an autoimmune disorder that occurs when the body destroys its own platelets. The condition occurs in approximately 50 to 150 people per million each year. About half of those affected are children. In adults, ITP affects women more often than men.

Large bruise on a woman's knee
 Photoboyco/Getty Images


ITP often does not cause any symptoms. Sometimes, a person can have a few symptomatic episodes and may not experience any effects between the episodes.

This condition can begin suddenly in children or adults—without a history of bleeding problems. You may notice unexplained bruises on your body or bleeding from your nose or mouth.

Symptoms of ITP may include:

  • Bruises may occur after minor bumps or for no apparent reason.
  • Petechiae, which are tiny reddish-purple dots can appear on the skin in clusters. They tend to appear on the lower legs and may resemble a rash.
  • Cuts take a long time to stop bleeding.
  • Nosebleeds or bleeding from the gums can occur.
  • Blood may appear in the urine or in bowel movements.
  • Women may have heavy menstrual bleeding.

Types of ITP

There are two main types of ITP, and they differ in the duration of the illness and in the age groups they affect.

  • Acute ITP is a temporary type of ITP. It generally lasts for less than six months. It is the most common type of ITP and occurs mainly in children—both boys and girls—usually between 2 and 4 years of age. It often occurs after a child has an infection or is sick with a virus. Children with acute ITP generally develop petechiae on their legs and stomach, and typically fully improve after the episode.
  • Chronic ITP is long-lasting, usually causing symptoms for six months or longer. It primarily affects adults, but sometimes teenagers or children may develop it. Adults are more likely to have problems that involve bleeding in the mouth or in the stool.


In some situations, serious bleeding can occur with ITP. This may result in major blood loss or even harmful bleeding into the brain, lungs, or kidneys.

Pregnant women who have ITP may develop bleeding issues during or after pregnancy. This requires close follow up with a hematologist throughout pregnancy and after delivery.


Thrombocytopenia means low blood platelets. Platelets are blood cells that help stop you from bleeding. They stick to each other and to proteins to form clots that seal wounds and cuts.

When your platelet level is low, wounds may not heal as quickly as they should. You can bruise easily because small bumps can cause you to bleed underneath your skin for a prolonged time. Petechiae are small bleeds that occur when capillaries (tiny blood vessels) tear. They tend to form near each other in small or large clusters.

Fragile skin in the nose and mouth can easily bleed. With ITP, your internal organs—such as the bladder, lungs, stomach, or intestines can bleed as well.


The condition is described as idiopathic because it is not known why some people develop ITP. It is not hereditary, and there aren't any underlying health reasons that make a person more predisposed to the condition.

There are some factors that tend to precipitate ITP, however—especially acute ITP. But an adult or child can develop the effects of ITP without any triggers.

Factors that frequently precede symptoms of ITP include:

Autoimmune ITP

ITP is usually caused by an autoimmune reaction in which the body attacks its own platelets. Antibodies are proteins that fight infection, but they can attack and destroy a person's own tissue. In ITP, the autoimmune reaction results in a low platelet level.


Diagnosis of ITP is made using a combination of methods. If you have symptoms, your healthcare provider will discuss your medical history with you. You will also have a physical examination, which includes an examination of your skin, heart, and lungs.

Blood Tests

You are likely to have diagnostic blood tests as part of your evaluation. Blood tests include a complete blood count (CBC) and electrolyte levels. A CBC provides a platelet count. Typically, there are low numbers of platelets in ITP.

White blood cells (WBCs), red blood cells (RBCs), and electrolyte levels tend to be normal in ITP.

Blood Smear

Your medical team may also want to look at your platelets under a microscope using a blood smear. The blood used for a blood smear is obtained with the same process as a regular blood sample used for a CBC. In ITP, the platelets have a normal shape and appearance on a blood smear.

Your medical team may also look at your WBCs and RBCs under a microscope. This test can help to assess whether you could have another cause of excessive bruising—such as leukemia or lymphoma—which are types of white blood cell cancer.


Most children with the acute type of ITP recover completely in about six months with no treatment. Adults with mild ITP also may not need treatment.

Management of chronic ITP is focused on increasing the number of platelets in the blood. There are several different treatment approaches.

Medical Therapies

Many of the medical treatments used for managing ITP are anti-inflammatory drugs that reduce the body's autoimmune attack against platelets. These medications are generally used for a few months or weeks at a time.

Corticosteroids like prednisone can be taken for several weeks or months to reduce inflammation. Azathioprine and Rituxan (rituximab) are immunosuppressants that have been used to decrease the inflammation in autoimmune diseases and in ITP.

Vincristine is a chemotherapeutic medicine often used to treat blood cancers such as leukemia, and it has also been used in the treatment of ITP. Newer medications, Promacta (eltrombopag), and Nplate (romiplostim) may help regulate platelet production to improve the platelet count in ITP.


There are several procedures that can be used to increase your platelet levels in ITP.

Intravenous immune globulin (IVIG) is a treatment that involves the injection of antibodies. It is usually given intravenously (through a needle in a vein) or by intramuscular (IM) injection. You may need several sessions of immune globulin for the treatment of ITP. This treatment has an anti-inflammatory effect, which reduces the autoimmune attack on platelets to increase the platelet count in ITP.

A splenectomy, which is the surgical removal of the spleen, can reduce the body's immune function. This approach may improve the platelet count in ITP. However, you may have an increased risk of developing infections if you have your spleen removed.

In situations when you have severe bleeding, you can receive a platelet transfusion. Donor platelets from a blood bank can be injected intravenously into your blood to increase the number of platelets in your body temporarily.

A Word From Verywell

If you or your child develops unexplained bruises or bleeding, it is important to get medical attention. There are a number of illnesses that can cause bleeding and bruising problems. If ITP is the diagnosis, the outcome can be good. Sometimes treatment to prevent or manage complications may be necessary.

Even if you are taking medicine for your condition or if your condition seems to improve for a while—be sure to get prompt medical attention if symptoms start again.

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