What are platelets ?
Platelets are one of the three types of blood cell, along with red and white blood cells. Platelets are small and sticky and their job is to prevent bruising and stop bleeding after an injury. The normal platelet count is between 150,000 and 450,000 platelets per cubic millimetre. This is usually expressed as 1.5 to 4.5 lacs.
What is idiopathic thrombocytopenic purpura (ITP) ?
ITP is a blood disorder characterized by an abnormal decrease in the number of platelets in the blood. Platelets are cells in the blood that help stop bleeding. A decrease in platelets can result in easy bruising, bleeding gums, and internal bleeding.
• "Idiopathic" means the cause is unknown.
• "Thrombocytopenia" means a decreased number of platelets in the blood.
• "Purpura" refers to the purple discoloring of the skin, as with a bruise.
What causes idiopathic thrombocytopenic purpura ?
Idiopathic means no known cause. In majority of the patients there is no apparent cause. In children , the most common cause is a trivial viral infection. However, when a cause can be identified, it may be a result of the following:
• medications (including over-the-counter medications)
• immune disorders
What are the symptoms of idiopathic thrombocytopenic purpura ?
With ITP, the platelet count is usually less than 1.0 lac. By the time significant bleeding occurs, the child may have a platelet count of less than 10,000. The lower the platelet count, the greater the risk of bleeding.
Because platelets help stop bleeding, the symptoms of ITP are related to increased bleeding. However, each person may experience symptoms differently. Symptoms may include the following:
Bruises (bleeding beneath the skin) is the commonest symptom. Petechiae (small bleeds beneath the skin) usually are seen on the shins (legs). In severe cases the patients may have bleeding in there gums, nose, urine and even in the head causing life threatening situation.
The symptoms of ITP may resemble other Haematology & Blood Disorders or medical problems.
How common is ITP and who does it affect ?
About four in every 100,000 children develop ITP each year. There seem to be two groups who develop ITP: young children and young adults. It is more common in girls than boys.
How is idiopathic thrombocytopenic purpura diagnosed ?
In addition to a complete medical history and physical examination, diagnostic procedures for idiopathic thrombocytopenic purpura includes complete blood count (CBC), blood film. Other investigations may be required. Sometimes, a bone marrow aspiration is performed to look at the production of platelets and to rule out any abnormal cells the marrow may be producing that could lower platelet counts.
Treatment for idiopathic thrombocytopenic purpura:
Specific treatment for idiopathic thrombocytopenic purpura will be determined by your haematologist based on age, other medical problems, severity of the disease and patient choices as well. Majority of the children donot need any treatment and can be just observed. The optimal treatment will be decided by your haematologist.
The options are:
1. Steroids : Steroids, if effective, will result in an increase in platelet count. Side effects may include irritability, stomach irritation, weight gain, hypertension, and acne.
2. Intravenous gamma globulin (IvIg): Intravenous gamma globulin (IvIg) is a protein that contains many antibodies and also slows the destruction of platelets. IvIg works more quickly than steroids (within 24 to 48 hours). It is expensive.
Other treatment options for ITP are:
3. Rh immune globulin This medication temporarily stops the spleen from destroying platelets. You must be Rh positive and have a spleen for this medication to be effective.
4. Splenectomy (removal of spleen) In some cases, the patient's spleen may need to be removed since this is the site of platelet destruction. This is considered more often in persons with chronic ITP to decrease the rate of platelet destruction.
5. Other treatment options include Azathioprine, cyclosporine, Vincristine etc. are mainly used for chronic ITP.
6. Rituximab It is a monoclonal antibody which can be used in some cases. It is expensive and can be only used under some circumstances. Your haematologist will tell you more about this treatment option.
Each patient is different and specific advice will be given as and when required.