Q: What is ITP?
A: Immune thrombocytopenia, or ITP, is an autoimmune disease. In autoimmune diseases, the body mounts an immune attack toward one or more seemingly normal organ systems. In ITP, platelets are the target. They are marked as foreign by the immune system and eliminated in the spleen and sometimes, the liver. In addition to increased platelet destruction, some people with ITP also have impaired platelet production.
Q: What are the phases of ITP?
A: Newly diagnosed ITP: within 3 months from diagnosis
Persistent ITP: 3 to 12 months from diagnosis. During this phase, patients have not reached spontaneous remission or maintained a complete response off therapy
Chronic ITP: lasting for more than 12 months
Severe ITP: presence of bleeding symptoms sufficient to mandate treatment, or occurrence of new bleeding symptoms requiring additional treatment with a different platelet-enhancing therapy or an increased dose
Refractory ITP: does not respond or is resistant to attempted forms of treatment
Q: What are platelets?
A: Platelets are relatively small, disc-shaped cells in our blood. They are required to maintain the integrity of our blood vessel walls and for blood to clot. Without a sufficient number of platelets, a person with ITP is subject to spontaneous bleeding or bruising. It is possible, with a very low platelet count, to have spontaneous bleeding including a cerebral hemorrhage.
Q: What is a normal platelet count?
A: According to Mosby’s Manual of Diagnostic and Laboratory Tests (4th Ed., 2010) normal platelet counts range from 150,000 to 400,000 per microliter of blood. The Merck Manual for Health Care Professionals (2011 Ed.) cites a normal platelet count range from 140,000 to 440,000. Reference ranges differ slightly depending upon the specific lab performing the test. Patients with platelets less than 140,000 are considered to have thrombocytopenia (low platelets). A platelet count less than 100,000 might be considered ITP according to the International Consensus Report on the Investigation and Management of Primary Immune Thrombocytopenia.People with platelet counts under 10,000 are considered to have a severe case of ITP. For many, a count of 30,000 or more is sufficient to prevent a serious bleed.
Q: What causes ITP?
A: The specific cause of ITP is unknown, but it is known that ITP causes the body’s immune system to destroy healthy platelets that can lead to easy or excessive bruising or bleeding. Some cases appear after a viral or bacterial infection, after immunizations, after exposure to a toxin, or in association with another illness such as lupus or HIV (human immunodeficiency virus).
Q: Can you inherit ITP?
A: ITP is not usually considered a disease that can be passed from one generation to another. There are cases in which multiple family members have been diagnosed with ITP, but most researchers consider these a misdiagnosis. The hereditary nature of autoimmune disorders is an evolving and exciting area of research, but there are still few definitive answers.
Q: What are the symptoms of ITP?
A: The symptoms of ITP vary greatly from person to person. Most people with ITP experience spontaneous bruising. Some find they have petechiae (pe-TEEK-ee-ay), tiny red dots on the skin caused by broken blood vessels or leaks in a capillary wall. If the platelet count is very low, other bleeding symptoms include blood blisters on the inside of the cheeks or blood in the urine or stool. In general, the more bleeding symptoms, the lower the platelet count.
Q: How is ITP diagnosed?
A: ITP is a diagnosis of exclusion. Because there is no definitive test to diagnose ITP, your doctor will first rule out other causes of low platelets, such as an underlying illness or medications you or your child may be taking. If not other cause is found the diagnosis is often ITP. In addition to asking about you or child’s medical history, your doctor will perform a physical exam and run one or more medical tests to confirm the diagnosis, including a complete blood count, blood smear or blood marrow exam.
Q: Can ITP be cured?
A: While there is no cure for ITP, many patients find their platelet count improves following treatment. What proves difficult for many ITP patients is finding the treatment that works for them without unwanted side effects. Some patients report that changing their diet or lifestyle helps them feel better. The disease can go into remission for a long time, perhaps for the remainder of a person’s life. ITP can also recur. There is currently no way to predict the course of the disease.
Q: How is ITP different in children than in adults?
A: ITP can be either acute (sudden onset, often temporary) or chronic (long lasting).
Q: How do children get ITP?
A: Doctors don’t know what causes ITP, but it often occurs in otherwise healthy children a few days or weeks after a viral infection. It’s thought that for some unknown reason this infection causes the immune system to lose the ability to distinguish between the body’s own cells and those of invaders. There is also some evidence that certain vaccines may trigger ITP, but this occurs in only a small percentage of cases. Why ITP happens in some children and not others who have had the same infection, virus or vaccine is not known.
The Platelet Disorder Support Association is here to empower you on a broad range of topics including diagnosis, prevention and management and treatment approaches.