Idiopathic Thrombocytopenic Purpura
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.
There are two forms of ITP, including the following:
- acute thrombocytopenic purpura
This is most commonly seen in young children (2 to 6 years old). The symptoms may follow a viral illness, such as chickenpox. Acute ITP usually has a very sudden onset and the symptoms usually disappear in less than six months (often within a few weeks). The disorder usually does not recur. Acute ITP is the most common form of the disorder.
- chronic thrombocytopenic purpura
The onset of the disorder can happen at any age, and the symptoms can last a minimum of six months, or several years. Adults have this form more often than children, but it does affect adolescents. Females have it two to three times more often than males. Chronic ITP can recur often and requires continual follow-up care with a blood specialist (hematologist).
Idiopathic means no known cause. However, when a cause can be identified, it may be a result of the following:
- medications (including over-the-counter medications)
- immune disorders
Normal platelet count is in the range of 150,000 to 450,000. With ITP, the platelet count is less than 100,000. 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:
- purpura - the purple color of the skin after blood has "leaked" under it. A bruise is blood under the skin. Persons with ITP may have large bruises from no known trauma. Bruises can appear at the joints of elbows and knees just from movement.
- petechia - tiny red dots under the skin that are a result of very small bleeds.
- bleeding in the mouth and/or in and around the gums
- blood in the vomit, urine, or stool
- bleeding in the head - this is the most dangerous symptom of ITP. Any head trauma that occurs when there are not enough platelets to stop the bleeding can be life threatening.
The symptoms of ITP may resemble other medical problems. Always consult your physician for a diagnosis.
In addition to a complete medical history and physical examination, diagnostic procedures for idiopathic thrombocytopenic purpura may include the following:
- complete blood count (CBC) - a measurement of size, number, and maturity of different blood cells in a specific volume of blood (to measure platelets).
- additional blood and urine tests (to measure bleeding time and detect possible infections)
- careful review of the patient’s medications
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.
Specific treatment for idiopathic thrombocytopenic purpura will be determined by your physician based on:
- your age, overall health, and medical history
- extent of the disease
- your tolerance for specific medications, procedures, or therapies
- expectations for the course of the disease
- your opinion or preference
When treatment is necessary, the two most common forms of treatment are steroids and intravenous gamma globulin:
Steroids help prevent bleeding by decreasing the rate of platelet destruction. Steroids, if effective, will result in an increase in platelet counts seen within two to three weeks. Side effects may include irritability, stomach irritation, weight gain, hypertension, and acne.
- intravenous gamma globulin (IVGG)
Intravenous gamma globulin (IVGG) is a protein that contains many antibodies and also slows the destruction of platelets. IVGG works more quickly than steroids (within 24 to 48 hours).
Other treatments for ITP may include:
- 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.
- medication changes
If it is a medication that is the suspected cause, discontinuation or changing the medication may be necessary.
- infection treatment
If infection is the cause for ITP, then treatment of the infection may result in higher platelet counts.
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.
- lifestyle changes, such as the following:
- use of protective gear
- avoidance of certain activities