Metabolome Changes With Diet-Induced Remission in Pediatric Crohn's Disease.

BACKGROUND & AIMS: The Crohn's disease (CD) exclusion diet (CDED) plus partial enteral nutrition (PEN) and exclusive enteral nutrition (EEN) both induce remission in pediatric CD. CDED+PEN is better tolerated and able to sustain remission. We characterized the changes in fecal metabolites induced by CDED+PEN and EEN and their relationship with remission. METHODS: A total of 216 fecal metabolites were measured in 80 fecal samples at week (W) 0, W6, and W12, of children with mild to moderate CD in a prospective randomized trial comparing CDED+PEN vs EEN. The metabolites were measured using liquid chromatography coupled to mass spectrometry. Metagenome Kyoto Encyclopedia of Genes and Genomes Orthology analysis was performed to investigate the differential functional gene abundance involved in specific metabolic pathways. Data were analyzed according to clinical outcome of remission (W6_rem), no remission (W6_nr), sustained remission (W12_sr), and nonsustained (W12_nsr) remission. RESULTS: A decrease in kynurenine and succinate synthesis and an increase in N-α-acetyl-arginine characterized CDED+PEN W6_rem, whereas changes in lipid metabolism characterized EEN W6_rem, especially reflected by lower levels in ceramides. In contrast, fecal metabolites in EEN W6_nr were comparable to baseline/W0 samples. CDED+PEN W6_rem children maintained metabolome changes through W12. In contrast, W12_nsr children in the EEN group, who resumed a free diet after week 6, did not. The metabolome of CDED+PEN differed from EEN in the purine, pyrimidine, and sphingolipid pathways. A significant differential abundance in several genes involved in these pathways was detected. CONCLUSION: CDED+PEN- and EEN-induced remission are associated with significant changes in inflammatory bowel disease-associated metabolites such as kynurenine, ceramides, amino acids, and others. Sustained remission with CDED+PEN, but not EEN, was associated with persistent changes in metabolites. CLINICALTRIALS: gov, Number NCT01728870.

Dietary Guidance From the International Organization for the Study of Inflammatory Bowel Diseases.

Recent evidence points to a plausible role of diet and the microbiome in the pathogenesis of both Crohn's disease (CD) and Ulcerative Colitis (UC). Dietary therapies based on exclusion of table foods and replacement with nutritional formulas and/or a combination of nutritional formulas and specific table foods may induce remission in CD. In UC, specific dietary components have also been associated with flare of disease. While evidence of varying quality has identified potential harmful or beneficial dietary components, physicians and patients at the present time do not have guidance as to which foods are safe, may be protective or deleterious for these diseases. The current document has been compiled by the nutrition cluster of the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) based on the best current evidence to provide expert opinion regarding specific dietary components, food groups and food additives that may be prudent to increase or decrease in the diet of patients with inflammatory bowel diseases to control and prevent relapse of inflammatory bowel diseases.

Nutrition in Pediatric Inflammatory Bowel Disease: A Position Paper on Behalf of the Porto Inflammatory Bowel Disease Group of the European Society of Pediatric Gastroenterology, Hepatology and Nutrition.

BACKGROUND AND AIMS: A growing body of evidence supports the need for detailed attention to nutrition and diet in children with inflammatory bowel disease (IBD). We aimed to define the steps in instituting dietary or nutritional management in light of the current evidence and to offer a useful and practical guide to physicians and dieticians involved in the care of pediatric IBD patients. METHODS: A group of 20 experts in pediatric IBD participated in an iterative consensus process including 2 face-to-face meetings, following an open call to Nutrition Committee of the European Society of Pediatric Gastroenterology, Hepatology and Nutrition Porto, IBD Interest, and Nutrition Committee. A list of 41 predefined questions was addressed by working subgroups based on a systematic review of the literature. RESULTS: A total of 53 formal recommendations and 47 practice points were endorsed with a consensus rate of at least 80% on the following topics: nutritional assessment; macronutrients needs; trace elements, minerals, and vitamins; nutrition as a primary therapy of pediatric IBD; probiotics and prebiotics; specific dietary restrictions; and dietary compounds and the risk of IBD. CONCLUSIONS: This position paper represents a useful guide to help the clinicians in the management of nutrition issues in children with IBD.

Sustained Diet-Induced Remission in Pediatric Crohn's Disease Is Associated With Kynurenine and Serotonin Pathways.

BACKGROUND: Both the Crohn's disease exclusion diet combined with partial enteral nutrition (CDED+PEN) and exclusive enteral nutrition (EEN) can induce remission in mild-to-moderate pediatric Crohn's disease and are associated with a marked decrease in fecal kynurenine levels. This suggests a link between clinical outcome of dietary therapy and changes in tryptophan metabolism pathways. Here, we characterize the changes in several fecal tryptophan metabolites induced by CDED+PEN or EEN and their association with remission. METHODS: A total of 21 tryptophan metabolites were quantified in fecal samples from a 12-week prospective randomized trial with CDED+PEN or EEN for induction of remission in mild to moderate pediatric Crohn's disease. Tryptophan metabolites at week 0 (W0), W6, and W12 of 73 samples were quantitatively measured by liquid chromatography coupled with triple quadrupole mass spectrometry, and data were analyzed according to clinical groups of baselines (W0), induced remission at W6, no remission, sustained remission at W12, and nonsustained remission. RESULTS: Reduction in components of the kynurenine pathway, such as kynurenine and quinolinic acid, were strongly associated with induced remission with both CDED+PEN and EEN, which were maintained in sustained remission. Specific serotonin pathway metabolites, such as melatonin, N-acetylserotonin, and 5-OH-tryptophan, were significantly increased in fecal samples from patients maintaining remission at W12 with both CDED+PEN and EEN. Importantly, in samples from patients failing to sustain remission, no changes were observed. Remission induction with EEN differs from CDED+PEN, particularly the moderate effects on indole pathway metabolites. The ratios of kynurenine and melatonin and quinolinic acid and melatonin perform well as markers for sustained remission. CONCLUSIONS: The reduction in specific kynurenine pathway compounds and the increase in serotonin pathway compounds are associated with diet-induced and sustained remission. Further studies are warranted to assess causality and the association of these metabolites with specific diet and lifestyle factors, affecting sustained clinical remission.

We show that fecal tryptophan metabolites are associated with remission following dietary therapy in a prospective clinical trial of pediatric Crohn's disease patients. Our study shows that reduction in some kynurenine pathway metabolites and the increase in serotonin pathway compounds are associated with diet-induced and sustained remission. These compounds may play a role in mediating the mechanism of action of dietary therapy.

The Crohn's disease exclusion diet for induction and maintenance of remission in adults with mild-to-moderate Crohn's disease (CDED-AD): an open-label, pilot, randomised trial.

BACKGROUND: The Crohn's disease exclusion diet (CDED) with partial enteral nutrition is effective for induction of remission in children with mild-to-moderate Crohn's disease. We aimed to assess the CDED in adults with Crohn's disease. METHODS: We did an open-label, pilot randomised trial at three medical centres in Israel. Eligible patients were biologic naive adults aged 18-55 years with mild-to-moderate Crohn's disease (defined by a Harvey-Bradshaw Index score of 5-14 points), a maximal disease duration of 5 years, with active disease on colonoscopy, or imaging with elevated inflammatory markers (C-reactive protein >5 mg/L or faecal calprotectin concentration >200 µ/g). Patients were randomly assigned (1:1) to CDED plus partial enteral nutrition or CDED alone for 24 weeks. Randomisation was via block randomisation (block sizes of six) using sealed, numbered, and opaque envelopes. Patients and investigators were aware of which group patients were assigned to due to the nature of the different interventions. The primary endpoint was clinical remission, defined as a Harvey-Bradshaw Index score of less than 5 at week 6. The primary endpoint was assessed in the intention-to-treat (ITT) population, which included all patients who used the dietary therapy for at least 48 h. We report results of the final analysis. This trial is registered with ClinicalTrials.gov, NCT02231814. FINDINGS: Between Jan 12, 2017, and May 11, 2020, 91 patients were screened, of whom 44 were randomly assigned to the CDED plus partial enteral nutrition group (n=20) or CDED alone group (n=24). 19 patients in the CDED plus partial enteral nutrition group and 21 patients in the CDED alone group received the allocated intervention for at least 48 h and thus were included in the ITT analysis. At week 6, 13 (68%) of 19 patients in the CDED plus partial enteral nutrition group and 12 (57%) of 21 patients in the CDED group had achieved clinical remission (p=0·4618). Among the 25 patients in remission at week 6, 20 (80%) were in sustained remission at week 24 (12 patients in the CDED plus partial enteral nutrition group and eight in the CDED alone group). 14 (35%) of 40 patients were in endoscopic remission at week 24 (eight patients in the CDED plus partial enteral nutrition group and six in the CDED alone group). No serious adverse events or treatment-related adverse events were reported in either group. INTERPRETATION: CDED with or without partial enteral nutrition was effective for induction and maintenance of remission in adults with mild-to-moderate biologic naive Crohn's disease and might lead to endoscopic remission. These data suggest that CDED could be used for mild-to-moderate active Crohn's disease and should be assessed in a powered randomised controlled trial. FUNDING: Azrieli Foundation and Nestle Health Science.

Treatment-Specific Composition of the Gut Microbiota Is Associated With Disease Remission in a Pediatric Crohn's Disease Cohort.

BACKGROUND: The beneficial effects of antibiotics in Crohn's disease (CD) depend in part on the gut microbiota but are inadequately understood. We investigated the impact of metronidazole (MET) and metronidazole plus azithromycin (MET+AZ) on the microbiota in pediatric CD and the use of microbiota features as classifiers or predictors of disease remission. METHODS: 16S rRNA-based microbiota profiling was performed on stool samples from 67 patients in a multinational, randomized, controlled, longitudinal, 12-week trial of MET vs MET+AZ in children with mild to moderate CD. Profiles were analyzed together with disease activity, and then used to construct random forest models to classify remission or predict treatment response. RESULTS: Both MET and MET+AZ significantly decreased diversity of the microbiota and caused large treatment-specific shifts in microbiota structure at week 4. Disease remission was associated with a treatment-specific microbiota configuration. Random forest models constructed from microbiota profiles before and during antibiotic treatment with metronidazole accurately classified disease remission in this treatment group (area under the curve [AUC], 0.879; 95% confidence interval, 0.683-0.9877; sensitivity, 0.7778; specificity, 1.000; P < 0.001). A random forest model trained on pre-antibiotic microbiota profiles predicted disease remission at week 4 with modest accuracy (AUC, 0.8; P = 0.24). CONCLUSIONS: MET and MET+AZ antibiotic regimens in pediatric CD lead to distinct gut microbiota structures at remission. It may be possible to classify and predict remission based in part on microbiota profiles, but larger cohorts will be needed to realize this goal.