Predictors for spontaneous remission in childhood chronic immune thrombocytopenia

This study examined the factors associated with spontaneous remission in children with chronic immune thrombocytopenia (ITP). We retrospectively analyzed the medical records of patients diagnosed with ITP from January 1988 to December 2019 at our institute. A total of 104 children with chronic ITP were identified. The median follow-up time from diagnosis of chronic ITP was 3.6 years (IQR 1.2-8.3, range 0.1-31.4). Fifteen (14.4%) patients with severe symptoms received specific platelet-elevating therapies, including splenectomy, rituximab, and thrombopoietin receptor agonists. Seven of them achieved remission. Among the patients with a platelet count < 30 × 10⁹/L at the time of diagnosis of chronic ITP, those who received specific platelet-elevating therapies had a higher remission rate compared to those who did not (HR: 4.66, 95% CI: 1.36-16.0). Sixteen patients (15.4%) developed systemic lupus erythematosus, 46 (44.2%) still had thrombocytopenia after a median follow-up of 6.8 years, and 42 (40.4%) achieved remission with a median time to remission of 2.0 years (IQR 0.6-4.1, range 0.1-15.7). The two independent predictive factors for spontaneous remission in childhood chronic ITP were platelet counts > 30 × 10⁹/L at the time of diagnosis of chronic ITP (HR: 3.16, 95% CI: 1.51-6.62) and persistently negative ANA at follow-up (HR: 6.12, 95% CI: 1.46-25.7). The cumulative probabilities of spontaneous remission at 10 years post-diagnosis of chronic ITP were 72.2% for patients without risk factor compared to 0% for patients with two risk factors.