Mucosal Healing and Bacterial Composition in Response to Enteral Nutrition Vs Steroid-based Induction Therapy-A Randomised Prospective Clinical Trial in Children With Crohn's Disease

Aims: Exclusive enteral nutrition [EEN] is as efficacious as corticosteroids [CS] to induce remission in Crohn's disease [CD], without their adverse effects. EEN seems to be more efficient than steroids to induce mucosal healing, but the underlying molecular mechanisms are only sparsely understood. We aimed in the present work to study the anti-inflammatory effects of EEN with Modulen IBD (R) vs CS in active paediatric CD, and to assess its modulatory effects on the intestinal microbiota as compared with steroids. Materials and Methods: Nineteen patients with new-onset active CD (Harvey-Bradshaw index [HBI] > 5), aged from 6 to 17 years, were included in this prospective randomised induction trial with CS [n = 6] or EEN [n = 13]. Patients were assessed at Weeks 0 and 8 using clinical parameters HBI, endoscopic findings (Crohn's Disease Endoscopic Index of Severity [CDEIS] score) and analysis of faecal microbiota composition. Results: At 8 weeks, clinical remission [HBI < 5] was achieved in 13/13 patients on EEN and 5/6 patients on steroids; the mucosal healing rate was significantly higher in the EEN [89%] compared with steroid group [17%]. There were no significant differences between groups regarding biological markers, but the intestinal microbiota profiles shifted upon EEN-induced remission to a higher proportion of Ruminococcus bacteria compared with steroid-induced remission [p = 0.049], and with higher proportions of bacteria belonging to Clostridium in EEN-treated patients. Conclusions: Both steroid and EEN induced clinical remission. However, patients with EEN-induced remission showed a higher rate of mucosal healing and this was associated with a different gut microbiota compositional shift in these children.