Predictors of response to emergent therapies in paediatric immune thrombocytopenia

Emergent therapies (ET), which include intravenous immunoglobulin (IVIG), corticosteroids and intravenous anti-Rho(D) immunoglobulin, are used to treat acute episodes of bleeding in children with immune thrombocytopenia (ITP). There are currently no known biomarkers or clinical features predictive of treatment response to any specific ET. Thus, the treatment of ITP remains largely trial and error, exposing patients to potentially ineffective medications, which are often expensive and associated with adverse effects. We therefore sought to identify the predictors of treatment response through comparison of clinical characteristics in paediatric patients with ITP responsive to ET versus those non-responsive to ET. We identified high rates of non-response to ET in our cohort of 511 children diagnosed with ITP over a recent 5-year period. Through a multivariable logistic regression model, we identified the presence of secondary ITP, the presence of systemic lupus erythematosus, a positive baseline direct antiglobulin test (DAT) and a high baseline IgA level as predictors of non-response to IVIG. In the future, management guidelines that incorporate predictors of response could help individualize treatment for each patient, achieving better response rates that ensure less bleeding-related morbidity and avoid unnecessary side effects.