Idiopathic Thrombocytopenia Purpura

Idiopathic Thrombocytopenia Purpura, or ITP, is a disorder characterized by excessive bruising and bleeding.  This bleeding and bruising is a result of an unusually low platelet count.  Platelets are the components in your blood, responsible for causing the blood to clot.  The normal platelet count is 150,000-450,000 platelets per microliter of blood. A child with ITP will have platelet counts below 20,000 platelets per microliter of blood. This disorder is also known as Immune Thrombocytopenia Purpura. It affects children and adults. With children the disease is preceded by a viral infection, usually acute in nature and recovery from it is completely.

Etiology or Causes

The definition of idiopathic is “of unknown cause” hence we get the labeling of this disorder.  The exact cause is unknown. What we do know, however, is that with this disorder, the immune system begins attacking the platelets as if they were foreign substances. The antibodies that the immune system produces, will attach themselves to the platelets. This is the means for marking the platelets for destruction.  The function of the spleen is to help the body fight off infection. When the spleen recognizes the antibodies, it will remove the antibody and platelet attached to it, from the circulatory system.

Signs and Symptoms

This disease may not have any overt symptoms. However, when they do occur, they may include easy bruising (purpura) and prolonged bleeding.  You might see superficial bleeding under the skin that appears as a red, pinpoint rash.  This is known as a petechial rash. Nose bleeds are common. You might have bleeding gums, particularly, after dental work.  You could see blood in the urine and stools. For teenage girls you may experience an unusually heavy menstrual flow.  Fatigue is not uncommon because as you bleed, you will become anemic.

Diagnostic Test

To diagnose this disorder, the doctor would begin with a physical examination. Your doctor will look for signs of bleeding under your child’s skin. You may be asked about recent episodes of bleeding, previous illnesses and medications your child has recently taken.

Complete blood cell count: this test is the gold standard for diagnosing this disease. The number of red and white blood cells and platelets are counted from a sample of blood. In this disorder, you may find the red and white blood cell counts may be normal, however, the number of platelets will be low.

Bone Marrow test: Platelets are manufactured in the bone marrow, the soft, spongy tissue in the center of large bones. A procedure known as a bone marrow biopsy is performed which is the removal of solid bone marrow. The removal of the liquid portion of the bone marrow, known as a bone marrow aspiration, often accompanies the biopsy procedure. The two samples are sent to the lab for testing. With ITP, the bone marrow test will be normal.
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

Treatment and Prevention

When treating ITP, the goal is to ensure a safe platelet count and prevent bleeding complications while minimizing treatment side effects.

If your child’s platelet count drops below 20,000 / microliters, they might receive corticosteroids or intravenous immunoglobulin (IVIG).  Prednisone, which is a steroid, could be administered for 2-3 weeks or until the platelet count increases above 30,000 / microliters. The IVIG is only given for 1-3 days.  Another drug, known as Rituximab (Rituxan) may be used in severe cases of ITP, when corticosteroids are ineffective. The mechanism of action for this drug is reducing the immune system response.   The newest medications approved to treat ITP are called Thrombopoietin Receptor Agonists. Romiplostim (Nplate) and Eltrombopag (Promacta) are two of these drugs. These drugs work by helping your bone marrow produce more platelets, which results in the cessation of bruising and bleeding.

There have been cases where those with ITP were also infected with Helicobacter Pylori.  This is the same bacteria responsible for most peptic ulcers. It has also been recognized that by eliminating the bacteria, the platelet count has increased. However, the outcome from this form of treatment has been inconsistent and more studies need to be done.

A transfusion of platelets is usually not indicated unless your child is facing a life-threatening condition. ITP is usually self-limiting. For those cases where ITP persists for a year or longer, the removal of the spleen (splenectomy) may be necessary.  The removal of your spleen results in the loss of the mechanism that is causing the rapid destruction of the platelets. However, when you remove the spleen you also increase your vulnerability to infections. Fortunately, if after having a splenectomy your child is otherwise healthy, the risk of an infection is low.

In regards to prevention, you should restrict your child from activities that could result in trauma, such as contact sports. Medications such as aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), and antihistamines should be avoided because these medications can precipitate the development of anemia in your child.

Prognosis

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.

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.  A referral to a Pediatric Hematologist is recommended, if your child develops ITP.  It’s also important to seek medical advice if you’re an adolescent 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.