Idiopathic thrombocytopenic purpura (ITP) is a disorder in which the blood doesn’t clot normally. This can cause excessive bruising and bleeding. An unusually low level of platelets, or “thrombocytes,” in the blood, causes ITP. ITP is also called immune thrombocytopenic purpura.
Platelets are produced in the bone marrow. They help stop bleeding by clumping together to form a clot that seals cuts or small tears in blood vessel walls. If your blood doesn’t have enough platelets, it’s slow to clot. Internal bleeding or bleeding on or under the skin can result.
People with ITP often have many purple bruises called purpura on the skin or mucous membranes inside the mouth. These bruises may also appear as pinpoint-sized red or purple dots on the skin called petechiae. Petechiae may look like a rash.
ITP can occur in both children and adults. According to the Mayo Clinic, it’s more common in women than men. Children are more likely to develop this condition after a viral illness, such as the mumps or measles.
The two types of ITP are acute (short-term) and chronic (long-lasting).
Acute ITP is the most common form of the disorder. It usually lasts less than six months and mainly occurs in children.
Chronic ITP lasts six months or longer. It’s most commonly seen in adults, although teenagers and younger children can be affected.
The word “idiopathic” means “of unknown cause.” This means the exact cause of ITP hasn’t been identified. However, it’s generally believed that most cases of ITP are triggered by an autoimmune response that causes the immune system to view platelets as foreign bodies instead of the person’s own cells. In response, the immune system produces antibodies that mark platelets for destruction and removal by the spleen, which lowers the platelet count.
In children, ITP most commonly follows a virus, such as the flu, measles, or mumps. In adults, ITP can occasionally occur after a viral infection, but it’s more commonly triggered by an immune disorder, pregnancy, or the use of certain drugs.
ITP isn’t contagious and cannot be passed from one person to another.
The most common symptoms of ITP are:
- bruising easily
- pinpoint-sized petechiae, often on the lower legs
- spontaneous nosebleeds
- bleeding from the gums (for example, during dental work)
- blood in the urine
- blood in the stool
- abnormally heavy menstruation
- prolonged bleeding from cuts
- profuse bleeding during surgery
Some people with ITP have no symptoms.
Your doctor will perform a complete physical exam. They’ll ask you about your medical history and the medications you’re taking.
Your doctor will also order a blood test that includes a complete blood count. The blood test may also include a test to determine if your blood contains platelet antibodies.
Your doctor may also perform a blood smear, in which some of your blood is placed on a glass slide and viewed under a microscope to verify the number of platelets seen in the complete blood count.
If you have a low platelet count, your doctor may also order a bone marrow test. If you have ITP, your bone marrow will be normal. This is because your platelets are destroyed in the bloodstream and spleen after they leave the bone marrow. If your bone marrow is abnormal, your low platelet count will likely be caused by another disease, not ITP.
Your doctor will choose your treatment based on the total number of platelets you have and on how often and how much you bleed. In some cases, treatment isn’t needed. For example, children that develop the acute form of ITP usually recover within six months without any treatment.
Adults with less severe cases of ITP may also not require treatment. However, your doctor will still want to monitor your platelet count to make sure you don’t need treatment in the future.
If you or your child requires treatment, your doctor will likely prescribe medications as the first course of treatment. The most common medications used to treat ITP include:
Your doctor may prescribe a corticosteroid, such as prednisone, which can increase your platelet count by decreasing the activity of your immune system.
Intravenous Immune Globulin (IVIG)
If your bleeding has reached a critical level or you are going to have surgery and need to increase your platelet count quickly, you may be given intravenous immune globulin (IVIG).
Thrombopoietin Receptor Agonists
Thrombopoietin receptor agonists, including romiplostim and eltrombopag, help prevent bruising and bleeding by causing your bone marrow to produce more platelets.
If these medications don’t improve your symptoms, your doctor may choose to prescribe other drugs, including:
Immunosuppressants inhibit the activity of the immune system. They include:
However, they have significant side effects.
New medications that increase platelet production are being studied in clinical trials. Two of these, eltrombopag and AMG 531, appear to be well-tolerated. However, studies are continuing to determine whether they are safe and effective.
Some people with ITP are also infected with Helicobacter pylori, which is the same bacteria that causes most peptic ulcers. Antibiotic therapy to eliminate H. pylori has helped increase platelet counts in some people.
If you have severe ITP and medication doesn’t improve your symptoms or platelet count, your doctor may advise surgery to remove your spleen. This is called a splenectomy. Your spleen is located in your upper left abdomen.
Splenectomy isn’t usually performed in children because of the high rate of spontaneous remission, or unexpected improvement.
Severe or widespread ITP requires emergency treatment. This usually includes transfusions of concentrated platelets and intravenous administration of a corticosteroid such as methylprednisolone, IVIG, or both.
Your doctor may also advise you to make some lifestyle changes, including the following:
- Avoid certain over-the-counter drugs that can affect platelet function, including aspirin, ibuprofen (Advil, Motrin), and the blood-thinning medication warfarin (Coumadin).
- Limit your intake of alcohol because consuming too much alcohol can adversely affect blood clotting.
- Choose low-impact activities instead of competitive sports or other high-impact activities to decrease your risk of injury and bleeding.
Treatment for pregnant women with ITP depends on the platelet count. If you have a mild case of ITP, you probably won’t need any treatment other than careful monitoring and regular blood tests.
If you have an extremely low platelet count or excessive bleeding, you’re more likely to experience serious, heavy bleeding during and after delivery. In these cases, your doctor will work with you to determine a treatment plan that will help maintain a safe platelet count without adversely affecting your baby.
Although most babies born to mothers with ITP aren’t affected by the disorder, some are born with or develop a low platelet count soon after birth. In most cases, the platelet count will return to normal without any treatment. Treatment may be necessary for babies with very low platelet counts.
The most dangerous complication of ITP is bleeding, especially bleeding into the brain, which can be fatal. However, serious bleeding is rare.
The treatments for ITP can have more risks than the disease itself. The long-term use of corticosteroids can cause serious side effects, including:
- a loss of muscle mass
- an increased risk of infection
- high blood sugar
Surgery to remove the spleen permanently increases your risk of infection and the risk of becoming ill if you get an infection. It’s important to watch for any symptoms of infection and report them to your doctor promptly.
In the majority of people with ITP, the condition isn’t serious or life-threatening.
Acute ITP in children often resolves within six months without treatment.
Chronic ITP can last for many years. People can live for many decades with the disease, even those with severe cases. Many people with ITP are eventually able to discontinue treatment safely.