Immune thrombocytopenia (THROM-bo-si-toe-PE-ne-ah), or ITP, is a bleeding disorder. In ITP, the blood doesn't clot as it should. This is due to a low number of blood cell fragments called platelets (PLATE-lets) or thrombocytes (THROM-bo-sites).
Platelets are made in your bone marrow along with other kinds of blood cells. They stick together (clot) to seal small cuts or breaks on blood vessel walls and stop bleeding.
Without enough platelets, bleeding can occur inside the body (internal bleeding) or underneath or from the skin (external bleeding).
People who have ITP often have purple bruises called purpura (PURR-purr-ah). These bruises appear on the skin or mucous membranes (for example, in the mouth). Bleeding from small blood vessels under the skin causes purpura.
People who have ITP also may have bleeding that causes tiny red or purple dots on the skin. These pinpoint-sized dots are called petechiae (peh-TEE-kee-ay). Petechiae may look like a rash.
Petechiae and Purpura
People who have ITP also may have nosebleeds, bleeding from the gums during dental work, or other bleeding that's hard to stop. Women who have ITP may have menstrual bleeding that's heavier than normal.
A lot of bleeding can cause hematomas (he-mah-TO-mas). A hematoma is a collection of clotted or partially clotted blood under the skin. It looks or feels like a lump.
Bleeding in the brain as a result of ITP is very rare, but can be life threatening if it occurs.
In most cases, an autoimmune response is thought to cause ITP. Normally, your immune system helps your body fight off infections and diseases. But if you have ITP, your immune system attacks and destroys its own platelets. The reason why this happens isn't known.
ITP can't be passed from one person to another.
Types of Immune Thrombocytopenia
The two types of ITP are acute (temporary or short-term) and chronic (long-lasting).
Acute ITP generally lasts less than 6 months. It mainly occurs in children—both boys and girls—and is the most common type of ITP. Acute ITP often occurs after a viral infection.
Chronic ITP lasts 6 months or longer and mostly affects adults. However, some teenagers and children do get this type of ITP. Chronic ITP affects women two to three times more often than men.
Treatment depends on the severity of bleeding and the platelet count. In mild cases, treatment may not be needed.
For most children and adults, ITP isn't a serious or life-threatening condition.
Acute ITP in children often goes away on its own within a few weeks or months and doesn't return. In 80 percent of children who have ITP, the platelet count returns to normal within 6 to 12 months. Treatment may not be needed.
For a small number of children, ITP doesn't go away on its own and may require further medical or surgical treatment.
Chronic ITP varies from person to person and can last for many years. Even people who have severe forms of chronic ITP can live for decades. Most people who have chronic ITP can stop treatment at some point and maintain a safe platelet count.
- Idiopathic (id-ee-o-PATH-ick) thrombocytopenic purpura
- Immune thrombocytopenic purpura
- Autoimmune thrombocytopenic purpura
In most cases, an autoimmune response is thought to cause immune thrombocytopenia (ITP).
Normally, your immune system helps your body fight off infections and diseases. In ITP, however, your immune system attacks and destroys your body's platelets by mistake. Why this happens isn't known.
In some people, ITP may be linked to viral or bacterial infections, such as HIV, hepatitis C, or H. pylori.
Children who have acute (short-term) ITP often have had recent viral infections. These infections may "trigger" or set off the immune reaction that leads to ITP.
Immune thrombocytopenia (ITP) is a fairly common blood disorder. Both children and adults can develop ITP.
Children usually have the acute (short-term) type of ITP. Acute ITP often develops after a viral infection.
Adults tend to have the chronic (long-lasting) type of ITP. Women are two to three times more likely than men to develop chronic ITP.
The number of cases of ITP is rising because routine blood tests that can detect a low platelet count are being done more often.
ITP can't be passed from one person to another.
Screening and Prevention
You can't prevent immune thrombocytopenia (ITP), but you can prevent its complications.
- Talk with your doctor about which medicines are safe for you. Your doctor may advise you to avoid medicines that can affect your platelets and increase your risk of bleeding. Examples of such medicines include aspirin and ibuprofen.
- Protect yourself from injuries that can cause bruising or bleeding.
- Seek treatment right away if you develop any infections. Report any symptoms of infection, such as a fever, to your doctor. This is very important for people who have ITP and have had their spleens removed.
Signs, Symptoms, and Complications
Immune thrombocytopenia (ITP) may not cause any signs or symptoms. However, ITP can cause bleeding inside the body (internal bleeding) or underneath or from the skin (external bleeding). Signs of bleeding may include:
- Bruising or purplish areas on the skin or mucous membranes (such as in the mouth). These bruises are called purpura. They're caused by bleeding under the skin, and they may occur for no known reason.
- Pinpoint red spots on the skin called petechiae. These spots often are found in groups and may look like a rash. Bleeding under the skin causes petechiae.
- A collection of clotted or partially clotted blood under the skin that looks or feels like a lump. This is called a hematoma.
- Nosebleeds or bleeding from the gums (for example, during dental work).
- Blood in the urine or stool (bowel movement).
Any kind of bleeding that's hard to stop could be a sign of ITP. This includes menstrual bleeding that's heavier than normal. Bleeding in the brain is rare, and its symptoms may vary.
A low platelet count doesn't directly cause pain, problems concentrating, or other symptoms. However, a low platelet count might be associated with fatigue (tiredness).
Your doctor will diagnose immune thrombocytopenia (ITP) based on your medical history, a physical exam, and test results.
Your doctor will want to make sure that your low platelet count isn't due to another condition (such as an infection) or medicines you're taking (such as chemotherapy medicines or aspirin).
Your doctor may ask about:
- Your signs and symptoms of bleeding and any other signs or symptoms you're having
- Whether you have illnesses that could lower your platelet count or cause bleeding
- Medicines or any over-the-counter supplements or remedies you take that could cause bleeding or lower your platelet count
During a physical exam, your doctor will look for signs of bleeding and infection. For example, your doctor may look for purplish areas on the skin or mucous membranes and pinpoint red spots on the skin. These are signs of bleeding under the skin.
You'll likely have blood tests to check your platelet count. These tests usually include:
- A complete blood count. This test checks the number of red blood cells, white blood cells, and platelets in your blood. In ITP, the red and white blood cell counts are normal, but the platelet count is low.
- A blood smear. For this test, some of your blood is put on a slide. A microscope is used to look at your platelets and other blood cells.
You also may have a blood test to check for the antibodies (proteins) that attack platelets.
If blood tests show that your platelet count is low, your doctor may recommend more tests to confirm a diagnosis of ITP. For example, bone marrow tests can show whether your bone marrow is making enough platelets.
If you're at risk for HIV, hepatitis C, or H. pylori, your doctor may screen you for these infections, which might be linked to ITP.
Some people who have mild ITP have few or no signs of bleeding. They may be diagnosed only if a blood test done for another reason shows that they have low platelet counts.
Treatment for immune thrombocytopenia (ITP) is based on how much and how often you're bleeding and your platelet count.
Adults who have mild ITP may not need any treatment, other than watching their symptoms and platelet counts. Adults who have ITP with very low platelet counts or bleeding problems often are treated.
The acute (short-term) type of ITP that occurs in children often goes away within a few weeks or months. Children who have bleeding symptoms, other than merely bruising (purpura), usually are treated.
Children who have mild ITP may not need treatment other than monitoring and followup to make sure their platelet counts return to normal.
Medicines often are used as the first course of treatment for both children and adults.
Corticosteroids (cor-ti-co-STEER-roids), such as prednisone, are commonly used to treat ITP. These medicines, called steroids for short, help increase your platelet count. However, steroids have many side effects. Some people relapse (get worse) when treatment ends.
The steroids used to treat ITP are different from the illegal steroids that some athletes take to enhance performance. Corticosteroids aren't habit-forming, even if you take them for many years.
Other medicines also are used to raise the platelet count. Some are given through a needle inserted into a vein. These medicines include rituximab, immune globulin, and anti-Rh (D) immunoglobulin.
Medicines also may be used with a procedure to remove the spleen called splenectomy (splee-NECK-tuh-mee).
If medicines or splenectomy don't help, two newer medicines—eltrombopag and romiplostim—can be used to treat ITP.
Removal of the Spleen (Splenectomy)
If needed, doctors can surgically remove the spleen. This organ is located in the upper left abdomen. The spleen is about the size of a golf ball in children and a baseball in adults.
The spleen makes antibodies (proteins) that help fight infections. In ITP, these antibodies destroy platelets by mistake.
If ITP hasn't responded to medicines, removing the spleen will reduce the destruction of platelets. However, it also may raise your risk for infections. Before you have the surgery, your doctor may give you vaccines to help prevent infections.
If your spleen is removed, your doctor will explain what steps you can take to help avoid infections and what symptoms to watch for.
Some people who have ITP with severe bleeding may need to have platelet transfusions and be hospitalized. Some people will need platelet transfusions before having surgery.
For a platelet transfusion, donor platelets from a blood bank are injected into the recipient's bloodstream. This increases the platelet count for a short time.
For more information about platelet transfusions, go to the Health Topics Blood Transfusion article.
Some infections can briefly lower your platelet count. Treating the infection may help increase your platelet count and reduce bleeding problems.
Some medicines can lower your platelet count or cause bleeding. Stopping the medicine can sometimes help raise your platelet count or prevent bleeding.
For example, aspirin and ibuprofen are common medicines that increase the risk of bleeding. If you have ITP, your doctor may suggest that you avoid these medicines.
If you have immune thrombocytopenia (ITP), you can take steps to prevent complications. Lifestyle changes and ongoing care can help you manage the condition.
Try to avoid injuries, especially head injuries, that can cause bleeding in the brain. For example, don't take part in contact sports, such as boxing, football, or karate. Other sports, such as skiing or horseback riding, also put you at risk for injuries that can cause bleeding.
Some safe activities are swimming, biking (with a helmet), and walking. Ask your doctor about physical activities that are safe for you.
Take precautions such as regular use of seatbelts and wearing gloves while working with knives and other tools.
If your child has ITP, ask his or her doctor whether you need to restrict your child's activities.
You may want to find a doctor who is familiar with treating people who have ITP. For example, hematologists are doctors who specialize in diagnosing and treating blood disorders. Discuss with your doctor how to manage ITP and when to seek medical care.
Talk with your doctor before taking prescription medicines or over-the-counter medicines, supplements, vitamins, or herbal remedies. Some medicines and supplements can affect platelets and increase your chance of bleeding. Common examples are aspirin or ibuprofen. Your doctor may advise you to avoid these medicines.
Watch for symptoms of infection, such as a fever, and report them to your doctor promptly. If you've had your spleen removed, you may be more likely to become ill from certain infections.
Immune Thrombocytopenia in Pregnancy
In women who are pregnant and have ITP, the ITP usually doesn't affect the baby. However, some babies may be born with or develop low platelet counts soon after birth.
The babies' platelet counts almost always return to normal without any treatment. Treatment can speed up recovery in the babies whose platelet counts are very low.
Treatment for ITP during pregnancy depends on a woman's platelet count. If treatment is needed, the doctor will take a close look at the possible effects of the treatment on the unborn baby.
Women who have mild cases of ITP usually can go through pregnancy without treatment. Pregnant women who have very low platelet counts or a lot of bleeding are more likely to have heavy bleeding during delivery or afterward. To prevent heavy bleeding, these women usually are treated.
The National Heart, Lung, and Blood Institute (NHLBI) leads or sponsors many studies aimed at preventing, diagnosing, and treating heart, lung, blood, and sleep disorders.