Oral Fecal Microbiota Transplantation in Pediatric Ulcerative Colitis

Ulcerative colitis (UC) is characterized by chronic inflammation of the colon of undetermined origin. Their incidence is increasing dramatically in the paediatric population.

Pediatric-onset inflammatory bowel disease (IBD) is characterized by a greater severity than adult IBD. Although great progress has been made in recent years, the pathogenesis of IBD is not fully elucidated. During UC, an imbalance in the composition of gut microbiota, called "dysbiosis", has been identified. This dysbiosis is notably characterized by an increased proportion of pro-inflammatory microorganisms and a decreased proportion of anti-inflammatory microorganisms. The current treatments used in IBD mainly target the immune system through immunosuppressants, and help to shorten flairs and prevent recurrences, but there is no curative treatment.

From a therapeutic point of view, the correction of this dysbiosis is thus an attractive approach. Until now, efficacy of microbiome-based therapies such as probiotics or antibiotics has been disappointing in IBD. Fecal microbiota transplantation (FMT) consists of the administration of fecal material from a donor into the intestinal tract of a recipient to change their microbiota composition and restore healthy conditions. FMT has been successfully used for many years for the treatment of Clostridioides difficile infection. Recent studies seem to show a benefit of FMT in UC.

The investigator's main hypothesis is that the replacement of a dysbiotic microbiota by a 'healthy' microbiota by FMT can modify the richness of UC patient's microbiota and has a positive impact on the disease course.

Once steroid-induced remission will be achieved, patients will be included and randomised to receive either FMT by frozen stool capsules or enemas. They will receive 3 doses at 0, 1 and 2 months. They will be followed for one year with stool samples collected every 3 months. Clinical and laboratory data will be collected.

• Success of FMT with frozen stool capsules defined by an increase in the richness of the recipient's microbiota at 12 months [Срок оценки: 12 months after the first FMT]
• Success of FMT by stool enema defined by an increase in the richness of the recipient's microbiota at 6 and 12 months [Срок оценки: 6 and 12 months after the first FMT]
• Success of FMT with frozen stool capsules on the change of recipient dysbiotic microbiota at 6 and 12 months [Срок оценки: 6 and 12 months after the first FMT]
• Success of FMT by enema on the change of recipient dysbiotic microbiota at 6 and 12 months [Срок оценки: 6 and 12 months after the first FMT]
• Success of FMT with frozen stool capsules on the richness and change of mucosal microbiota at 12 months [Срок оценки: 12 months]
• Success of FMT by enema on the richness and change of mucosal microbiota at 12 months [Срок оценки: 12 months]
• Success of FMT with frozen stool capsules on the change of mucosal recipient dysbiotic microbiota at 6 and 12 months [Срок оценки: 6 and 12 months after the first FMT]
• Success of FMT by enema on the change of mucosal recipient dysbiotic microbiota at 6 and 12 months [Срок оценки: 6 and 12 months after the first FMT]
• FMT with frozen stool capsules Feasibility [Срок оценки: At inclusion, 1 and 2 months after each FMT]
• FMT by enema Feasibility [Срок оценки: At inclusion, 1 and 2 months after each FMT]
• Ulcerative colitis clinical relapse [Срок оценки: 6 and 12 months]
• Ulcerative colitis Endoscopic relapse [Срок оценки: 12 months]