Idiopathic Trombocytopenic PurpuraI TP

ITP, also called immune thrombocytopenic purpura, is a disorder of bleeding or clotting that affects the platelets which are the main blood cells that have a key role in forming clots. ITP is characterized by easy bruising or bleeding.

Idiopathic implies that the exact cause of ITP is not known. It is believed that the defense system of the body called the immune system recognizes the platelets as being foreign entities and attacks them to facilitate their destruction in the blood stream and spleen. The spleen is an organ situated close to the stomach that acts as a graveyard of defective cells and help s to remove them from the blood. The platelet counts in the blood fall.

The counts which usually are between 150,000 to 450,000 platelets per microliter may fall to below 20,000 hence increasing the risk of bleeding. Very low counts below 10,000 platelets can cause internal bleeding without any precipitating factor or trigger.

ITP can affect anybody. Women, however are believed to be more likely to develop the ITP disease, so are the elderly. Children and adults of any age can develop ITP.

ITP in adults is persistent as compared to that in children, lasts for a longer period, and does not seem to be precipitated by viral illnesses. Though women are more prone, ITP can affect anybody irrespective of age or gender.

Children develop an acute and short lasting episode of ITP after a viral illness like measles, mumps, or a respiratory illness. It is possible that the viral infections act as a trigger to stimulate activity of the immune system against the platelets.

Symptoms

ITP may be absolutely symptom free or may cause episodes of extreme bleeding that need emergency medical care. People with ITP may develop bruises on the skin even after trivial trauma.

Any cut in the skin may bleed long and more. The bleeding can be spontaneous too. It manifests in the form of small pinpoint spots that may be red or purple in color and are more common on the lower legs. This type of rash is called purpura.

There can be a localized bleeding in one site leading to a collection of blood. This is called a hematoma and feels like a lump. There can be spontaneous bleeding from the gums or nose.

Blood may appear in urine or stools and there may be heavy bleeding during the monthly menstrual cycles in females.

If such people undergo a surgery, there may be excessive bleeding during the procedure. Patients my feel tired and weak due to bleeding. Medical help should be sought for any episode of bleeding, in particular for the extreme bleeding.

Diagnosis

ITP is a diagnosis of exclusion, i.e. the doctor may rule out other possible causes of bleeding before making a diagnosis of ITP.

After a detailed talk about the symptoms and the patterns of bleeding, the doctor may request for a blood test for complete blood count and the bleeding and clotting times. This will reveal the low numbers of platelets and prolonged bleeding and clotting times.

In addition, a blood smear may be done. This enables a study of the shape and size of blood cells under the microscope.

A bone marrow biopsy or aspiration is another test. This is done by inserting a needle through the skin into one of the superficial bones like the chest bone to take a sample of the marrow which is a soft tissue present in the bones where the platelets and blood cells are produced.

A bone marrow examination in ITP typically reveals normal platelets as the cells are destroyed in the blood stream after they are released from the marrow.

Children have ITP that is different from that in adults. ITP in children may not warrant a treatment as it may resolve by itself after few weeks or months. Around 80% children may recover within 6 months. Some may however have a prolonged illness. In them, it is treated as in adults.

Unlike children, very few adults with ITP have a spontaneous recovery. The goal of purpura treatment is to ensure a good platelet count and prevent bleeding.

  • Consumption of medicines like aspirin that can inhibit platelet function or warfarin that can cause blood thinning should be discontinued.
  • The most common medicines used for treating ITP are the corticosteroids. These decrease the activity of the immune system and check the destruction of platelets.
  • Steroids should be begun and tapered in a step wise manner. Once the platelet count is restored, these can be gradually withdrawn. These are usually required to two to six weeks and may be started again in case of relapse.
  • The injections of Intravenous immune globulin (IVIG) are used when platelet counts need to be restored within a short span like in the case of a surgery.
  • Another new class of drugs is the thrombopoietin receptor agonists like romiplostim and eltrombopag which help the bone marrow to produce more platelets and hence reduce bruising and bleeding.
  • If these medical measures do not help, then a splenectomy may be performed, i.e. the spleen may be surgically removed. This helps by removing the main of destruction of platelets.
  • In an emergency situation of extreme bleeding, platelets concentrates may be transfused and steroids may be given by injections into the blood vessels.
  • If none of these measures help, medicines like rituximab, cyclophosphamide, or azathioprine are used to suppress the immune system.
  • Any infection affecting the person should be treated with infection fighting medicines called antibiotics. The goal of treatment is to safely ensure a platelet count that with prevent bleeding.

ITP in pregnant women may be difficult to diagnose as a rise in blood pressure or other problems in pregnancy can lead to a fall in platelet count. Pregnancy in itself can lead to low counts when it is called a gestational thrombocytopenia.

ITP in pregnancy is not believed to harm the baby but some babies may develop a transient fall in platelets after birth. This usually returns to normal in few weeks to months. Pregnant women with ITP are at higher risk of bleeding during and after child birth.

Not all pregnant women with ITP may need treatment. Mild cases need not be treated. Only the moderate and symptomatic cases of ITP need treatment in pregnancy. IVIG is the appropriate initial treatment.

Steroids and immunosuppressive medicines may be used only if the benefits outweigh the risks to the developing baby. Splenectomy if required should be best done only in second trimester and only for the severe cases.

As delivery approaches, a sample of the baby’s blood may be collected from a vessel in the head of the baby through the abdomen of the mother to predict the risk of bleeding in the baby.

ITP needs some lifestyle changes. It is good to prevent injuries and to not engage in vigorous physical activities or sports. Alcohol and blood thinning medicines should be avoided and any infections should be treated. You can live and enjoy a normal life with proper awareness and a little precaution.