ITP is a bleeding disorder in which the immune system destroys platelets that are necessary for normal blood clotting. People with the disease have too few platelets in their blood, usually below 50,000/mm3. This pathology is also called immune thrombocytopenic purpura.
How it occurs and risk factors for ITP
Idiopathic thrombocytopenic purpura develops when certain cells of the immune system produce antibodies against platelets. Platelets help blood to clot by clumping together to plug small holes in damaged blood vessels. The antibodies attach to the platelets and the spleen destroys the platelets carrying the antibodies.
In children, the disease sometimes follows a viral infection. In adults, it is most often a chronic (long-term) disease and may occur after a viral infection, with the use of certain drugs, during pregnancy or as part of an immune disorder.
Idiopathic thrombocytopenic purpura affects women more often than men and is more common in children than in adults. In children, the disease affects both sexes equally. It occurs in about 5 cases per 100,000 live births under the age of 15 years.
Symptoms of ITP
Abnormally heavy menstruation, bleeding into the skin causing skin rashes that look like small red spots (petechial rash), prone to hematoma formation, and nose or mouth bleeding.
Diagnosis of ITP
First of all, a good medical history should be taken to look for personal and family history of bleeding, followed by a systematic physical examination to look for bleeding lesions, especially on the skin and mucous membranes.
Laboratory tests will be performed to study how the blood clots and to check the platelet count:
– A complete blood count or hemogram shows a low platelet count.
– Blood coagulation tests are usually normal (prothrombin activity, partial thromboplastin time and fibrinogen).
– Bleeding time is prolonged, as it is a direct reflection of platelet function in terms of how they aggregate.
– Platelet-associated antibodies can be detected.
– Biopsy or bone marrow aspirate: to rule out a central or bone marrow origin of thrombopenia, they show a higher than normal number of cells called megakaryocytes, which are the precursor cells of platelets.
Treatment of ITP
In children, the disease often goes away without treatment; however, some may need treatment.
Adults are usually started on an anti-inflammatory steroid. In some cases, surgery to remove the spleen (splenectomy) is recommended. This will increase the platelet count in about half of the patients. Today it is left as a residual treatment in the face of the emergence of other types of more effective drugs. Splenectomy involves the systematic vaccination of the patient against certain types of germs by provoking a marked humoral (antibody-mediated) immunosuppression.
If the disease does not improve, other treatments may be used such as: injections with high doses of gamma globulin (an immune factor), drugs that inhibit the immune system, immunosuppressants or monoclonal antibodies. Drugs that stimulate platelet production at the central or medullary level (megakaryocyte colony-stimulating factor). Filtration of antibodies out of the bloodstream (Plasmapheresis) and anti-RhD therapy for people with certain blood types.
People with ITP should not take aspirin, ibuprofen, or oral anticoagulants because these drugs interfere with platelet function or blood clotting, and bleeding may occur.
Prognosis of ITP
With treatment, the likelihood of remission (symptom-free period) is good. Rarely, Idiopathic Thrombocytopenic Purpura can become a chronic ailment in adults and recur even after a period without symptoms.
Complications of ITP
Sudden, severe bleeding from the gastrointestinal tract may occur. Bleeding into the brain may occur. It is important to go to the emergency room if severe or evolving bleeding occurs. The causes and risk factors are unknown, except in children where it may be related to a viral infection.