[Clinical study of pulsed high- dose dexamethasone treatment in 38 children with primary immune thrombocytopenic purpura].

Objective: To evaluate the efficacy and safety of pulsed high- dose dexamethasone(HDD)treatment in children with primary immune thrombocytopenic purpura(ITP). Method: ITP children who failed to first-line therapy from September 2013 to September 2014 were given pulsed HDD treatment, dexamethasone was administered at a dosage of 0.6 mg ·kg-1 ·d-1 (maximum 40 mg/d)for 4 consecutive days. The cycle was repeated every 28 days for 6 months. Results: ①A total of 38 cases were enrolled, 26 boys and 12 girls, median age was 54(6-151)months, median duration of disease was 6(1- 72)months, 9 cases was newly diagnosed ITP, 13 cases with persistent ITP, 16 cases with chronic ITP. Median platelet count before treatment was 16.3(1.0- 30.0)× 109 /L. ②A median follow- up time was 180(90- 554)days. Treatment response was obtained in 17 cases(44.7%), including 7 cases(18.4%)with complete response(CR), 10 cases(26.3%)response(R); the median time to response was 80.5(23-245)days. Of 17 CR/R cases, 3 turned to no response, with a median duration of response 63(37-67)days. Of 38 cases, 21(55.3%)was no response, but the bleeding symptoms in 85.7% of this group improved. ③ Only 1 patient had mild reversible side effects during treatment. ④ The percentage of CD4 + CD25 + Foxp3+ T cells is higher in effective group than that in ineffective group[(7.54±1.50)% vs (5.69±1.95)%, P =0.049]. Univariate analyses suggested that the efficacy of HDD treatment in children with megakaryocyte count <300/slide is better than that >300/slide( P =0.049). Conclusion: Pulsed HDD treatment is a comparatively safe and effective choice for children with ITP who failed to first-line therapy. Children with less than 300 megakaryocytes or higher CD4+ CD25+ Foxp3+ T cells may be more suitable for the therapy.