الملخص

• Isolated thrombocytopenia in the absence of other causes; thought to be due to an autoimmune phenomenon.
• Typically found in children often with a preceding viral illness and an abrupt onset, or in middle-aged women who present with thrombocytopenia with or without bleeding.
• Examination is usually normal. Petechiae may be present on mucosal membranes or the lower limbs. Bruising is common. Mucosal bleeding may also occur in most severe cases. Intracranial bleeding is reported in less than 1% of adults and less than 0.5% of children.
• FBC and smear show isolated thrombocytopenia. Bone marrow biopsy is required in patients over 60 years old to exclude myelodysplastic syndrome or lymphoproliferative disorders.
• Treatment is based on platelet count and bleeding symptoms. Any patient with life-threatening bleeding, regardless of platelet count, should be treated with a combination therapy of corticosteroids, IV immunoglobulin, and platelet transfusion.
• In children prognosis is good, with up to 80% achieving a spontaneous remission. In adults, two-thirds respond to initial treatment or splenectomy; however, 30% develop chronic disease and up to 5% to 10% of these die of haemorrhage or of treatment-related toxicity. Mortality is higher in older patients and in those unresponsive to several lines of treatment.