Clinical and Fecal Microbial Changes With Diet Therapy in Active Inflammatory Bowel Disease

Goal: To determine the effect of the specific carbohydrate diet (SCD) on active inflammatory bowel disease (IBD). Background: IBD is a chronic idiopathic inflammatory intestinal disorder associated with fecal dysbiosis. Diet is a potential therapeutic option for IBD based on the hypothesis that changing the fecal dysbiosis could decrease intestinal inflammation. Study: Pediatric patients with mild to moderate IBD defined by pediatric Crohn's disease activity index (PCDAI 10-45) or pediatric ulcerative colitis activity index (PUCAI 10-65) were enrolled into a prospective study of the SCD. Patients started SCD with follow-up evaluations at 2, 4, 8, and 12 weeks. PCDAI/PUCAI, laboratory studies were assessed. Results: Twelve patients, ages 10 to 17 years, were enrolled. Mean PCDAI decreased from 28.1 +/- 8.8 to 4.6 +/- 10.3 at 12 weeks. Mean PUCAI decreased from 28.3 +/- 23.1 to 6.7 +/- 11.6 at 12 weeks. Dietary therapy was ineffective for 2 patients while 2 individuals were unable to maintain the diet. Mean C-reactive protein decreased from 24.1 +/- 22.3 to 7.1 +/- 0.4 mg/L at 12 weeks in Seattle Cohort (nL < 8.0 mg/L) and decreased from 20.7 +/- 10.9 to 4.8 +/- 4.5 mg/L at 12 weeks in Atlanta Cohort (nL < 4.9 mg/L). Stool microbiome analysis showed a distinctive dysbiosis for each individual in most prediet microbiomes with significant changes in microbial composition after dietary change. Conclusions: SCD therapy in IBD is associated with clinical and laboratory improvements as well as concomitant changes in the fecal microbiome. Further prospective studies are required to fully assess the safety and efficacy of dietary therapy in patients with IBD.