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Inherited thrombocytopenia
Patients with inherited thrombocytopenia and their families should be educated about their diagnosis to avoid unnecessary investigations and especially potentially dangerous medical/surgical treatment for ITP. In the past, patients with inherited thrombocytopenia have been treated with platelet transfusions (reserved for cases of bleeding or its prevention, e.g. prior to surgery). While the fear of sensitization has dominated restriction of platelet transfusion, the availability of leukoreduction has greatly decreased this risk. Recently, one of the two thrombopoietin-receptor agonists, eltrombopag, was investigated as a possible treatment option in MYH9-related disorders (May-Hegglin anomaly associated with the MYH9 gene) thrombocytopenia, with at least some success in 12 of 15 patients. Preliminary results have also been obtained in patients with WAS. Fear of induction of malignancy has restricted its use in syndromes in which there is myelodysplastic syndrome or a potential for the development of leukemia, for example congenital amegakaryocytic thrombocytopenia (CAMT), TAR, GATA-1 (globin transcription factor 1)-related X-linked thrombocytopenia, and familial leukemia-thrombocytopenia. The option of allogeneic stem cell transplantation is reserved for inherited thrombocytopenias with a high risk of marrow failure or a high risk of acute leukemia. According to the Medscape reference library [12], the incidence rates for ITP are as follows: in the US there are 66 adult cases and 50 childhood cases per 1,000,000 per year; in Denmark and England there are 10 to 40 cases per 1,000,000 per year; and in Kuwait there are 125 cases per 1,000,000 per year. Many cases of ITP can be left untreated, and spontaneous remission in children is common. However, counts of under 50 × 109/L are usually monitored with regular blood tests, and those with counts of under 10-20 × 109/L are usually treated, as the risk of serious spontaneous bleeding, especially intracranial hemorrhage, is much higher with lower platelet counts. Any patient experiencing severe bleeding symptoms secondary to thrombocytopenia should also be treated.