The most common cause of thrombocytopenia in children is idiopathic thrombocytopenic purpura (ITP). ITP, characterized by purple bruising on the skin, results when the immune system attacks platelets for reasons unknown. In children, it is thought that viral infections can trigger acute ITP lasting less than six months. Medical treatment may not be required for mild cases of ITP since these often self-resolve. Thrombocytopenia in children can also be a side effect of leukemia, bone marrow failure, or a prescribed medication.
Acute ITP is the most common cause of pediatric thrombocytopenia. Idiopathic is a term indicating that there is no known cause for the drop in platelets. What is understood is that the immune system is destroying platelets, resulting in easy bruising and abnormal amounts of bleeding. It is possible for a viral infection to trigger ITP and thus thrombocytopenia in children.
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In most children, ITP is acute and may be mild enough to resolve on its own without medical intervention. If it persists for more than six months, however, the condition becomes chronic. The most common treatment involves corticosteroids that interrupt the immune system’s attack on blood platelets. In severe cases, splenectomy and stronger immunosuppressive medications may be necessary to get the condition under control.
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Other conditions can cause thrombocytopenia in children. For instance, bone marrow infections and some cancers can cause thrombocytopenia. This is because platelets are produced in the bone marrow. Additionally, chemotherapy and similar drugs can decrease platelet production. A vitamin B12 or folic acid deficiency can also result in thrombocytopenia in children.
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A child with thrombocytopenia has significantly fewer platelets in his or her blood. A platelet is a cell that facilitates proper blood clotting. When the blood does not clot properly, dangerous amounts of internal or external bleeding can result. In rare and severe cases, thrombocytopenia in children can result in fatal brain and intestinal bleeding.
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The typical telltale symptom of thrombocytopenia in children is easy and disproportionate bruising. Petechiae, or tiny purplish spots, can appear on the legs or elsewhere. Cuts and scrapes can bleed for an abnormally long time and there may be blood present in the child’s urine or stool. A child with this condition may also suffer from spontaneous nose bleeds or bleeding gums. A girl may notice increasingly heavy menstruation.
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Diagnosing thrombocytopenia in children usually requires only a physical exam and a simple blood test called a complete blood count (CBC). A child with thrombocytopenia generally has less than 150,000 platelets per microliter of blood. The prognosis depends on the underlying cause of the condition. Treating this cause is often the most effective way to treat thrombocytopenia. A doctor may decide not to treat a mild case, while other, more severe cases may require a blood transfusion or medications like corticosteroids.