Idiopathic thrombocytopenic purpura (ITP) is a disorder that can lead to easy or excessive bruising and bleeding. The bleeding results from unusually low levels of platelets — the cells that help your blood clot.
Idiopathic thrombocytopenic purpura, which is also called immune thrombocytopenic purpura, affects both children and adults. Children often develop idiopathic thrombocytopenic purpura after a viral infection and usually recover fully without treatment. In adults, however, the disorder is often chronic.
Treatment of idiopathic thrombocytopenic purpura depends on your symptoms, your platelet count and your age. If you don't have signs of bleeding and your platelet count isn't too low, treatment for idiopathic thrombocytopenic purpura usually isn't necessary. More serious cases may be treated with medications or, in critical situations, with surgery.
Idiopathic thrombocytopenic purpura (ITP) may have no symptoms. When signs and symptoms do occur, they may include:
- Easy or excessive bruising (purpura) — your skin naturally bruises and bleeds more easily as you age, but this shouldn't be confused with ITP
- Superficial bleeding into your skin that appears as a rash of pinpoint-sized reddish-purple spots (petechiae), usually on your lower legs
- Prolonged bleeding from cuts
- Spontaneous bleeding from nose
- Bleeding gums, especially after dental work
- Blood in urine or stools
- Unusually heavy menstrual flow
When to see a doctor
If you or your child has abnormal bleeding or bruising, or develops a rash of pinpoint-sized red spots, see your doctor. It's also important to seek medical advice if you're a woman who suddenly develops significantly increased menstrual bleeding, as this may be a sign of ITP.
Serious or widespread bleeding indicates an emergency and requires immediate care.
The exact cause of ITP isn't known. That's why it's referred to as idiopathic, which means "of unknown cause." It is known, however, that in people with idiopathic thrombocytopenic purpura, the immune system malfunctions and begins attacking platelets as if they were foreign substances.
Antibodies produced by your immune system attach themselves to the platelets, marking the platelets for destruction. The spleen, which helps your body fight infection, recognizes the antibodies and removes the platelets from your system. The result of this case of mistaken identity is a lower number of circulating platelets than is normal.
A normal platelet count is generally higher than 150,000 platelets per microliter of circulating blood. People with ITP often have platelet counts below 20,000. As the number of platelets decreases, your risk of bleeding increases. The greatest risk is when your platelet count falls very low — below 10,000 platelets per microliter. At this point, internal bleeding may occur despite a lack of any injury.
In most children with ITP, the disorder follows a viral illness, such as the mumps or the flu. It may be that an infection sets off the immune system, triggering it to malfunction.
ITP can occur in anyone at almost any age, but these factors increase your risk:
- Your sex. Women are about twice as likely to develop ITP as men are.
- Recent viral infection. Many children with ITP develop the disorder after a viral illness, such as mumps, measles or a respiratory infection.
The biggest risk associated with idiopathic thrombocytopenic purpura is bleeding, especially bleeding into the brain (intracranial hemorrhage), which can be fatal. Major bleeding is rare with ITP, however.
Complications are more likely to arise from the treatments used for chronic or severe ITP. Corticosteroids are a first line treatment because they help dampen the immune system attack on the platelets. But, long-term use of corticosteroids can cause serious side effects, including bone loss (osteoporosis), cataracts and high blood sugar levels, possibly leading to type 2 diabetes.
Removal of your spleen (splenectomy), which may be performed if corticosteroids aren't working, helps prevent the loss of platelets. However, removing the spleen also makes you permanently more vulnerable to infection. Fortunately, the risk of an overwhelming infection in a healthy person who has had a splenectomy is low.
Pregnant women with mild ITP usually have a normal pregnancy and delivery, though antibodies to platelets can cross the placenta and affect the baby's platelet count. In some cases, a baby may be born with a low number of platelets. If this happens, your baby's doctor will want to monitor your child for several days, because your baby's platelet count may drop before it starts to rise. It's likely that your baby's platelet count will improve without treatment, but if the count is very low, treatment can help the baby recover faster.
If you're pregnant and your platelet count is very low or you have bleeding, you have a greater risk of heavy bleeding during delivery. In such cases, you and your doctor may discuss treatment to maintain a stable platelet count, taking into account the effects on your baby.
Because a low platelet count may not cause symptoms, the problem is often discovered when you have a blood test for another reason. If your doctor thinks you might have ITP, you are likely to have further blood tests that require drawing a small amount of blood from a vein in your arm. You are also likely to be referred to a doctor who specializes in blood disorders (hematologist) for further evaluation and treatment.
Appointments, even with specialists, can be brief, and there's often a lot of ground to cover, so it can help to be prepared. Here are some tips to help you get ready for your appointment:
What you can do
- Write down all your symptoms — even those that seem unrelated to your current problem. Include key personal information, such as major stresses or recent life changes.
- Make a list of all medications, vitamins, herbs and over-the-counter drugs that you're taking. Even better, take the original bottles to your appointment.
- Take along a family member or friend. It can be difficult to remember all of the information provided during an appointment. The person who accompanies you may remember something that you forgot or missed.
- Write down questions for your doctor. Don't be afraid to ask questions or to speak up when you don't understand something your doctor says. Start with the problems that concern you most. If you run out of time, ask to speak with a nurse or physician's assistant or leave a message for your doctor.
Questions you may want to ask include:
- What tests are needed to confirm the diagnosis?
- Is this condition temporary or long lasting?
- What treatments are available, and what do you recommend?
- What will happen if I do nothing?
- What are the possible side effects of the treatments you're suggesting?
- I have another health condition. How can I best treat these conditions together?
- How can I avoid those side effects?
- Can you refer me to a website or other source, so I can learn more about this condition?
Doctors usually diagnose idiopathic thrombocytopenic purpura by excluding other possible causes of bleeding and a low platelet count, such as an underlying illness or medications you may be taking. If no other underlying problem is causing your signs and symptoms, then a diagnosis of ITP may be made.
To diagnose ITP, your doctor may need a:
- Physical exam, including a complete medical history. Your doctor will look for signs of bleeding under your skin, and will ask you about previous illnesses you've had and the types of medications and supplements that you've recently taken.
- Complete blood count. This common blood test is used to determine the number of white and red blood cells and platelets in a sample of your blood. With ITP, white and red blood cell counts are usually normal, but the platelet count is low.
- Blood smear. A sample of your blood is placed on a slide and observed under a microscope. This test is often used to confirm the number of platelets observed in a complete blood count.
- Bone marrow examination. Another test that may help identify the cause of a low platelet count is a bone marrow exam. Platelets are produced in your bone marrow — soft, spongy tissue in the center of your large bones. In some cases, a sample of solid bone marrow is removed in a procedure called a bone marrow biopsy. Or, you may have a bone marrow aspiration, which removes some of the liquid portion of your marrow. In many cases, both procedures are performed at the same time (bone marrow exam). Both the liquid and solid bone marrow samples are frequently taken from the same place on the back of one of your hipbones. A needle is inserted into the bone through an incision.
If you have ITP, your bone marrow will be normal because your low platelet count is caused by the destruction of platelets in your bloodstream and spleen — not by a problem with the bone marrow.
The goal of treating ITP is to ensure a safe platelet count and prevent bleeding complications while minimizing treatment side effects.
In children, idiopathic thrombocytopenic purpura usually runs its course without the need for treatment. About 80 percent of children with idiopathic thrombocytopenic purpura recover completely within six months. Even in children who develop chronic ITP, complete recovery may still occur, even years later.
Adults with mild cases of ITP may require nothing more than regular monitoring and platelet checks. But if your symptoms are troublesome and your platelet count remains low, you and your doctor may opt for treatment. Treatment usually consists of medications and sometimes surgery (splenectomy). Your doctor may also have you discontinue certain drugs that can further inhibit platelet function, such as aspirin, ibuprofen (Advil, Motrin IB, others) and the blood-thinning medication warfarin (Coumadin).
Common medications used to treat idiopathic thrombocytopenic purpura include:
Corticosteroids. The first line of therapy for ITP is a corticosteroid, usually prednisone, which can help raise your platelet count by decreasing the activity of your immune system. Once your platelet count is back to a safe level, you can gradually discontinue taking the drug under the direction of your doctor. In general, this takes about two to six weeks.
The problem is that many adults experience a relapse after discontinuing corticosteroids. A new course of corticosteroids may be pursued, but long-term use of these medications isn't recommended because of the risk of serious side effects, including weight gain, cataracts, high blood sugar, increased risk of infections and loss of calcium from your bones (osteoporosis). You and your doctor will want to weigh the benefits of the medication against these risks. If you need to take corticosteroids long term, your doctor will likely recommend that you take calcium and vitamin D supplements to help maintain your bone density.
- Intravenous immune globulin (IVIG). If you have critical bleeding or need to quickly increase your blood count before surgery, you may receive medications, such as immune globulin, given intravenously. These medications are quick and effective, but the effect usually wears off in a couple of weeks. Possible side effects include headache, nausea and fever. In certain people, Rho (D) immune globulin (WinRho) may be an option. This medication may cause fewer side effects than IVIG.
- Thrombopoietin receptor agonists. The newest medications approved to treat ITP are romiplostim (Nplate) and eltrombopag (Promacta). These drugs help your bone marrow produce more platelets, which helps prevent bruising and bleeding. Possible side effects include headache, joint or muscle pain, dizziness, nausea or vomiting, and an increased risk of blood clots.
- Biologic therapy. Rituximab (Rituxan) helps reduce the immune system response. It's generally used for people with severe ITP, and in those who corticosteroids don't help. Possible side effects include low blood pressure, fever, sore throat and rash.
Removal of your spleen (splenectomy)
If you have severe ITP and an initial course of prednisone hasn't helped, surgical removal of your spleen (splenectomy) may be an option. This quickly eliminates the main source of platelet destruction in your body and improves your platelet count, though it doesn't work for everyone. Splenectomy for ITP is not as routinely performed as it once was, however. Serious post-surgical complications sometimes occur, and not having a spleen permanently increases your susceptibility to infection.
Splenectomy is rarely performed in children because of their high rate of spontaneous remission.
Although rare, severe bleeding can occur with ITP, regardless of age or platelet count. Severe or widespread bleeding is life-threatening and demands emergency care. This usually includes transfusions of platelet concentrates, intravenous methylprednisolone (a type of corticosteroid) and intravenous immune globulin.
If neither the initial round of corticosteroids nor a splenectomy has helped you achieve remission and your symptoms are severe, your doctor may recommend another course of corticosteroids, usually at the lowest effective dose.
Other possible treatments include:
- Immunosuppressant drugs. Medications that suppress the immune system, such as cyclophosphamide (Cytoxan) and azathioprine (Imuran, Azasan), have been used to treat ITP, but they can cause significant side effects, and their effectiveness has yet to be proved. Possible side effects include fever, headache, nausea and vomiting, low blood pressure, hair loss, and dizziness.
- H. pylori treatment. Some people with ITP are also infected with Helicobacter pylori, the same bacteria that cause most peptic ulcers. Eliminating the bacteria has helped increase platelet count in some people, but the results for this therapy are inconsistent and need to be studied further.
Because of the potential complications of both the disease and its treatment, it's important for you and your doctor to carefully weigh the benefits and risks of treatment. For example, some people find that the side effects of treatment are more burdensome than the effects of the disease itself. Other factors that might affect your decision include whether or not you have other medical conditions or take medications that could increase your risk of bleeding, and whether or not you have an active lifestyle that could increase the risk of injury and bleeding.
If you have idiopathic thrombocytopenic purpura, the following steps may help control your risk of bleeding and other complications:
- Avoid platelet-impairing medications. Over-the-counter drugs, such as aspirin and ibuprofen (Advil, Motrin IB, others), can impair platelet function.
- Choose low-impact physical activities. Your doctor may recommend avoiding competitive sports or other activities that might increase the risk of injury and bleeding.
- Watch for signs of infection. If you've had your spleen removed, be alert for any signs of infection, including fever, and seek prompt treatment. Infection in someone who's had a splenectomy may be more severe, last longer and have more serious implications than in someone who still has an intact spleen.
Apr. 23, 2013
- What is idiopathic thrombocytopenic purpura? National Heart, Lung, and Blood Institute. http://www.nhlbi.nih.gov/health/health-topics/topics/itp/printall-index.html. Accessed Feb. 25, 2013.
- Longo DL, et al. Harrison's Online. 18th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=4. Accessed Feb. 25, 2013.
- Tintinalli JE, et al. Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 7th ed. New York, N.Y.: The McGraw Hill Companies; 2011. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=40. Accessed Feb. 25, 2013.
- Stone CK, et al. Current Diagnosis & Treatment Emergency Medicine. 7th ed. New York, N.Y.: The McGraw Hill Companies; 2011. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=718. Accessed Feb. 25, 2013.
- Guide to understanding ITP (immune thrombocytopenia). ITP Foundation. http://www.itpfoundation.org/itpdefined.htm. Accessed Feb. 25, 2013.
- Arnold DM. Positioning new treatments in the management of immune thrombocytopenia. Pediatric Blood & Cancer. 2013;60:S19.
- Idiopathic thrombocytopenic purpura (ITP). The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merckmanuals.com/professional/print/hematology_and_oncology/thrombocytopenia_and_platelet_dysfunction/immune_thrombocytopenic_purpura_itp.html. Accessed Feb. 25, 2013.
- Bussel JB. Traditional and new approaches to the management of immune thrombocytopenia: Issues of when and who to treat. Hematology/Oncology Clinics of North America. 2009;23:1329.