Idiopathic thrombocytopenic purpura (ITP), also known as immune thrombocytopenic purpura, is an autoimmune disorder that affects blood clotting due to an insufficient amount of blood platelets—tiny cells needed to form a blood clot. Because ITP prevents effective clotting, excessive and prolonged bruising and bleeding are common symptoms of this rare disease that can be triggered by a few different factors.
ITP Causes
ITP is an autoimmune disorder. With conditions like this, the body attacks and destroys healthy tissue or cells. Specifically ITP destroys antibodies attached to platelets that the body creates. The destruction leads to a low platelet count, which means not enough exist to form a blood clot when bleeding occurs. Here are some of the most common causes of this antibody destruction:
- Viral Infection: When diagnosed in children, the most common cause of ITP is the flu, measles, or mumps. ITP triggered by viral infection in children is usually temporary
- Drugs: Drug-induced thrombocytopenia is the result of platelet destruction or prevention of production due to certain medications. There are two types of drug-induced thrombocytopenia: immune and nonimmune. The immune type is caused by medicine that destroys platelets. The main medicine associated with this type is the blood thinner heparin. The nonimmune type, however, prevents bone marrow’s production of platelets. Such drugs that cause the nonimmune type include chemotherapy drugs and valproic acid, which is a seizure medicine. Keep your doctor informed about the medications you take.
- Pregnancy: Sometimes pregnancy can cause a drop in platelet production due to an overactive spleen. A continuous drop in platelet count in pregnancy is known as gestational thrombocytopenia.
ITP Risk Factors
Risk factors depend on age and gender. ITP is more common in women and children, affecting both boys and girls equally. In children the disorder is more likely to be temporary, but chronic cases are common among adults. Additionally those with illnesses that affect the immune system, such as leukemia, are also at risk.
- Age: Children two to four years of age following a recent viral infection are more likely to develop ITP.
- Gender: Women are twice as likely to develop ITP.
- Pregnancy: Expecting mothers may experience low platelet count due to an overactive spleen.
- Cancer: Certain chemotherapy drugs or cancers can trigger ITP.
