Objectives: We aimed to compare the efficacy of remission maintenance between infliximab "top-down" and "step-up" strategies in moderate to severe pediatric Crohn disease during 3 years. We also aimed to determine prognostic factors that may influence the relapse-free rate in these patients.
Methods: The present study was a retrospective review of a prospective cohort, based on an infliximab treatment protocol for pediatric Crohn disease used at Samsung Medical Center. A total of 31 patients (group A) were treated with early infliximab induction ("top-down" strategy) and 20 patients (group B) refractory to conventional therapy underwent infliximab treatment ("step-up" strategy). The efficacy of infliximab treatment was assessed by relapse-free rate and remission period rate for 3 years. A total of 11 prognostic factors that may influence the relapse-free rate were further analyzed.
Results: The relapse-free rates at 3 years were 35.5% (95% confidence interval [CI] 0.194-0.519) in group A and 15.0% (95% CI 0.037-0.335) in group B (P = 0.0094). Overall remission period rate for 3 years also showed a significant difference between the 2 groups (92.1% ± 7.2% vs 78.3% ± 16.6%; P = 0.005). Multivariable analysis revealed that the duration from the initial diagnosis to infliximab infusion was the only factor associated with relapse-free remission for 3 years (hazard ratio = 1.077; 95% CI 1.025-1.131).
Conclusions: "Top-down" strategy had a longer remission period compared with the "step-up" strategy in pediatric Crohn disease during a study period of 3 years, based on relapse-free rate and remission period rate. Earlier introduction of infliximab is recommended in pediatric patients with moderate to severe Crohn disease.