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According to the American Society of Hematology 2011 guidelines, treatment initiation is suggested when an adult patient is newly-diagnosed with a platelet count <30 × 109/L (grade 2C evidence), but in clinical practice various factors (e.g. bleeding tendency, age, medical history and concomitant medications) need to be taken into account. If therapy is required, the first-line treatment option is generally corticosteroids, with the recommended prednisone dose 1 mg/kg/day orally for up to 21-28 days depending upon response, followed by slow tapering. More prominent platelet responses have been reported with repeated pulses of high-dose dexamethasone 40 mg daily for 4 days, but no comparative data favoring dexamethasone exists. Also, intravenous immunoglobulin or intravenous anti-D (Rho[D] immune globulin) can be used as initial treatment with or without steroids. The initial intravenous immunoglobulin dose of either 0.4 g/kg/day for up to 5 days or, alternatively, a short course of high dose intravenous immunoglobulin (1 g/kg for 1-2 days) has been found to be effective. Most adult patients will relapse after initial treatment (or are refractory to first-line therapy) and require second-line therapy. The most effective second-line treatment option is splenectomy. The initial response rate is perhaps 80-85% with a 5-year response rate of 60-65%. Unfortunately, predictors of response to splenectomy are not well defined yet. Additional second-line treatment options with documented evidence of efficacy (allowing postponement of splenectomy) include many agents: azathioprine, cyclosporine, cyclophosphamide, danazol, dexamethasone, vinca alkaloids, mycophenolate mofetil, rituximab, and thrombopoietin-receptor agonists. The pros and cons of the leading agents have been recently summarized. Rituximab, the leading and original anti-CD20 monoclonal antibody (several others exist) is widely used in ITP, in various regimens and combinations with other drugs, for example with dexamethasone. The most commonly used rituximab schedule is intravenous infusion of 375 mg/m2 given once weekly for 4 weeks. Patel et al. recently reported 5-year outcomes of both children and adults. This study specifically selected responders to rituximab in order to assess the duration of response 5 or more years from initial treatment.