Treatment of Active Crohn's Disease With Exclusive Enteral Nutrition Diminishes the Immunostimulatory Potential of Fecal Microbial Products.

BACKGROUND: Exclusive enteral nutrition (EEN) is an effective treatment for active Crohn's disease (CD). This study explored the immunostimulatory potential of a cell-free fecal filtrate and related this with changes in the fecal microbiota and metabolites in children with active CD undertaking treatment with EEN. METHODS: Production of tumor necrosis factor α (TNFα) from peripheral blood mononuclear cells was measured following their stimulation with cell-free fecal slurries from children with CD, before, during, and at completion of EEN. The metabolomic profile of the feces used was quantified using proton nuclear magnetic resonance and their microbiota composition with 16S ribosomal RNA sequencing. RESULTS: Following treatment with EEN, 8 (72%) of 11 patients demonstrated a reduction in fecal calprotectin (FC) >50% and were subsequently labeled FC responders. In this subgroup, TNFα production from peripheral blood mononuclear cells was reduced during EEN (P = .008) and reached levels like healthy control subjects. In parallel to these changes, the fecal concentrations of acetate, butyrate, propionate, choline, and uracil significantly decreased in FC responders, and p-cresol significantly increased. At EEN completion, TNFα production from peripheral blood mononuclear cells was positively correlated with butyrate (rho = 0.70; P = .016). Microbiota structure (ß diversity) was influenced by EEN treatment, and a total of 28 microbial taxa changed significantly in fecal calprotectin responders. At EEN completion, TNFα production positively correlated with the abundance of fiber fermenters from Lachnospiraceae_UCG-004 and Faecalibacterium prausnitzii and negatively with Hungatella and Eisenbergiella tayi. CONCLUSIONS: This study offers proof-of concept data to suggest that the efficacy of EEN may result from modulation of diet-dependent microbes and their products that cause inflammation in patients with CD.

Treatment of active Crohn's disease with exclusive enteral nutrition diminishes the proinflammatory potential of fecal microbial components, hence suggesting a mechanism of action involving modulation of diet-dependent microbes and their products that cause gut inflammation.

Inflammation-related Proteins Support Diagnosis of Inflammatory Bowel Disease and Are Modified by Exclusive Enteral Nutrition in Children With Crohn's Disease, Especially of Ileal Phenotype.

BACKGROUND: The immunological effects of treatment with exclusive enteral nutrition (EEN) in Crohn's disease (CD) remain unknown. We characterized the plasma levels of inflammation-related proteins (IRPs) in children with CD and ulcerative colitis (UC) compared with noninflammatory controls (non-IBD) and explored the effect of EEN in CD. METHODS: Ninety-two IRPs were quantified using Olink proteomics in children with CD (n = 53), UC (n = 11), and non-IBD (n = 19). For 18 children with active CD, IRPs were measured before and after 8 weeks of EEN. Relationships with disease phenotype and response to EEN were studied. RESULTS: Compared with non-IBD, patients with active UC and CD had different levels of 27 (24 raised, 3 decreased) and 29 (26 raised, 3 decreased) IRPs, respectively. Exclusive enteral nutrition modified the levels of 19 IRPs (13 increased, 6 decreased including CCL23, interleukin-24, interleukin-6, and MMP-1). More pronounced changes in IRP profile were observed in patients with ileal involvement and a ≥50% decrease in fecal calprotectin during EEN compared with those with colonic involvement and a <50% decrease in fecal calprotectin, respectively. A machine-learning model utilizing baseline IRP profile predicted response to EEN with a sensitivity of 89%, specificity of 57%, and accuracy of 73%. Thymic stromal lymphopoietin was the most important IRP in the model, this being higher in responders. CONCLUSIONS: Inflammation-related proteins may be useful in the differential diagnosis of IBD. Exclusive enteral nutrition extensively modulated IRPs levels in children with active CD with more pronounced effects observed in patients who showed a reduction in FC and had ileal disease involvement.

Plasma inflammation-related proteins are altered in children with inflammatory bowel disease. In active Crohn's disease, exclusive enteral nutrition modified several of these proteins, particularly in disease involving the ileum and in patients whose fecal calprotectin levels significantly decreased.

Exclusive enteral nutrition impacts peripheral blood mononuclear cell profile of children with Crohn's disease.

The immunological effects of exclusive enteral nutrition (EEN) in the treatment of active Crohn's disease (CD) are yet to be unveiled. The present study investigated changes in peripheral blood mononuclear cell profiles in children with active CD following 8-week treatment with EEN. In nine children, EEN significantly decreased the number and frequency of circulating effector memory CD8+ T cells re-expressing CD45RA, with corresponding increases observed in the frequency of circulating central and effector memory CD8+ T cells. These signals were conserved when looking at a subgroup of patients who achieved remission, and another who demonstrated the highest level of compliance to EEN. We speculate that the increases in circulating central and effector memory CD8+ T cells may be related to the extensive microbiome-modifying effects of EEN dampening immune response within the gastrointestinal tract.

Gut metabolome and microbiota signatures predict response to treatment with exclusive enteral nutrition in a prospective study in children with active Crohn's disease.

BACKGROUND: Predicting response to exclusive enteral nutrition (EEN) in active Crohn's disease (CD) could lead to therapy personalization and pretreatment optimization. OBJECTIVES: This study aimed to explore the ability of pretreatment parameters to predict fecal calprotectin (FCal) levels at EEN completion in a prospective study in children with CD. METHODS: In children with active CD, clinical parameters, dietary intake, cytokines, inflammation-related blood proteomics, and diet-related metabolites, metabolomics and microbiota in feces, were measured before initiation of 8 wk of EEN. Prediction of FCal levels at EEN completion was performed using machine learning. Data are presented with medians (IQR). RESULTS: Of 37 patients recruited, 15 responded (FCal < 250 µg/g) to EEN (responders) and 22 did not (nonresponders). Clinical and immunological parameters were not associated with response to EEN. Responders had lesser (µmol/g) butyrate [responders: 13.2 (8.63-18.4) compared with nonresponders: 22.3 (12.0-32.0); P = 0.03], acetate [responders: 49.9 (46.4-68.4) compared with nonresponders: 70.4 (57.0-95.5); P = 0.027], phenylacetate [responders: 0.175 (0.013-0.611) compared with nonresponders: 0.943 (0.438-1.35); P = 0.021], and a higher microbiota richness [315 (269-347) compared with nonresponders: 243 (205-297); P = 0.015] in feces than nonresponders. Responders consumed (portions/1000 kcal/d) more confectionery products [responders: 0.55 (0.38-0.72) compared with nonresponders: 0.19 (0.01-0.38); P = 0.045]. A multicomponent model using fecal parameters, dietary data, and clinical and immunological parameters predicted response to EEN with 78% accuracy (sensitivity: 80%; specificity: 77%; positive predictive value: 71%; negative predictive value: 85%). Higher taxon abundance from Ruminococcaceae, Lachnospiraceae, and Bacteroides and phenylacetate, butyrate, and acetate were the most influential variables in predicting lack of response to EEN. CONCLUSIONS: We identify microbial signals and diet-related metabolites in feces, which could comprise targets for pretreatment optimization and personalized nutritional therapy in pediatric CD.

YouTube as a Source of Information for Food, Diet-Related Items, and Advisory Comments for the Management of Inflammatory Bowel Disease.

BACKGROUND: Patients with inflammatory bowel disease (IBD) often use the Internet to seek information beyond that received from healthcare professionals. This study assessed the perceptions of YouTube presenters on the role of diet in the management of IBD. METHODS: Videos discussing dietary aspects (food, diet-related items, and advisory comments [FODRIACs]) in the management of IBD were included. The perceptions of presenters toward each FODRIAC were labeled as positive, negative, or neutral/intermediate, and FODRIACs were classified according to their underlying role in the management of IBD (eg, symptom management, gut inflammation). Subgroup analysis was performed by type of video presenter (patients vs healthcare professionals), type of IBD (Crohn's disease vs ulcerative colitis), and reporting of scientific evidence supporting presenters' perceptions. RESULTS: We identified 122 FODRIACs within 160 videos. Patient videos received a higher number of likes (median 85 [interquartile range, 35-156]) than healthcare professional videos (median 44 [interquartile range, 16-1440]) (P = .01). Scientific evidence was cited in 2 (3%) of 76 patient videos compared with 25 (35%) of 71 healthcare professional videos (P < .001). Positive perceptions were expressed about avocadoes, salmon, bananas, white bread, and rice, whereas negative perceptions were reported for processed, high-fat and high-sugar foods and carbonated drinks. Fewer negative perceptions were expressed in videos supported by scientific evidence than in videos that lacked evidence (scientific: 4 positive, 0 negative vs nonscientific: 7 positive, 20 negative; P = .01). CONCLUSIONS: We have identified FODRIACs proposed as beneficial or detrimental in the management of IBD. The effect this information has on dietary practice as patients with IBD self-manage their condition needs further exploration.

Take-Home Messages from 20 Years of Progress in Dietary Therapy of Inflammatory Bowel Disease.

BACKGROUND: A significant body of literature has interrogated the critical role of diet in the development and management of inflammatory bowel disease (IBD). SUMMARY: This review provides a summary and critical appraisal of the literature in this area, focussing on four distinct themes: nutritional epidemiology, animal and in vitro experiments, enteral nutrition, and food-based dietary therapies. KEY MESSAGES: Nutritional epidemiology and data from experiments in animals indicate that a western-type diet pattern is associated with increased risk of IBD onset. However, these findings have not been consistently replicated in the dietary management of IBD. Exclusive enteral nutrition (EEN) is the only dietary therapy with reproducible evidence of efficacy in the management of active Crohn's disease (CD). Use of EEN may also be useful for improving perioperative outcomes in CD, and as an adjuvant therapy to biologic therapy. Several dietary therapies for CD and ulcerative colitis have been proposed in the literature, but replication in well-controlled studies is needed before their routine use enters the clinical setting. Precision nutritional therapy might be an attractive therapeutic paradigm in a heterogenous disease like IBD. However, no recommendations for personalised dietary therapy can currently be made, and it is imperative we unravel the complex interplay between diet and gut inflammation before we are able to do so. Undoubtedly, diet is of critical importance in the development and management of IBD. However, the exact mechanism by which diet causes gut inflammation is still elusive, and dietary guidance is difficult to formulate.

Improved clinical outcomes with early anti-tumour necrosis factor alpha therapy in children with newly diagnosed Crohn's disease: real world data from the international prospective PIBD-SETQuality inception cohort study.

BACKGROUND & AIMS: Treatment guidelines for paediatric Crohn's disease (CD) suggest early use of anti-tumour necrosis factor alpha (anti-TNF) in high-risk individuals. The aim is to evaluate the effect of early anti-TNF in a real-world cohort. METHODS: Children with newly-diagnosed CD were prospectively recruited at 28 participating sites of the international observational PIBD-SETQuality study. Outcomes were compared at 3 months, 1 and 2 years between patients receiving early anti-TNF (<90 days after diagnosis) and those not receiving early anti-TNF. Outcomes included sustained steroid-free remission (SSFR) without treatment intensification (specified as SSFR*) and sustained steroid-free mild/inactive disease without treatment intensification (specified as SSFMI*). Penalised logistic regression model-based standardisation was applied to estimate the relative risks (RR) of early therapy on outcomes. RRs were estimated for high-risk and low-risk patients based on presence of predictors of poor outcome (POPOs) and disease activity at diagnosis. RESULTS: In total, 331 children (median age 13.9 years [IQR 12.2 - 15.3]) were enrolled, with 135 (41%) receiving early anti-TNF. At 1 year, patients on early anti-TNF had higher rates of SSFR* (30% vs. 14%, p<0.001) and SSFMI* (69% vs. 33%, p<0.001), with RRs of 2.95 (95%CI 1.63-5.36) and 4.67 (95%CI 2.46-8.87) respectively. At 1 year, the RRs for SSFMI* were higher, and statistically significant in high-risk patients, i.e. those with moderate/severe disease compared to mild/inactive disease at diagnosis (5.50 [95%CI 2.51-12.05]) vs. 2.91 [95%CI 0.92-9.11]), and those with any POPO compared to no POPO (5.05 [95%CI 2.45-10.43] vs. 3.41 [95%CI 0.54-21.7]). CONCLUSION: In this cohort of children with newly-diagnosed CD, early anti-TNF demonstrated superior effectiveness in high-risk patients.

Nationwide Real-World Exclusive Enteral Nutrition Practice Over Time: Persistence of Use as Induction for Pediatric Crohn's Disease and Emerging Combination Strategy With Biologics.

BACKGROUND: Exclusive enteral nutrition (EEN) is the recommended first-line induction treatment in pediatric patients with active luminal Crohn's disease (CD). We aimed to provide a nationwide overview of evolving EEN practices during an era of increasing biologic use. METHODS: We analyzed a prospectively identified nationwide cohort of newly diagnosed pediatric patients with CD in Scotland between January 1, 2015, and June 30, 2022. Patients who received EEN for any indication were divided into 6-monthly epochs and examined over time. Differences during the COVID-19 pandemic (March 16, 2020, to July 19, 2021) were examined. Data were retrospectively collected from electronic medical records: demographics, anthropometrics, concomitant treatments, aspects of EEN administration, and remission/response rates. Descriptive statistics and linear regression were used for analyses. RESULTS: A total of 649 patients with CD were identified (63% male; median age 12.6 [interquartile range, 10.8-14.8] years); 497 (77%) of 649 received EEN as postdiagnosis induction therapy with a median course length of 7.7 (interquartile range, 5.9-8.0) weeks. Including repeat courses, 547 EEN courses were examined. An increasing incidence of CD was observed over time with no significant changes in EEN usage, remission or response rates, nasogastric tube usage, or course completion (all P > .05). Increasing use of EEN combined with biologics (combination induction) as first-line induction was observed over time (P < .001). Considering COVID-19, lower rates of EEN usage were observed (P = .008) with no differences in remission, oral administration, and course completion rates (all P > .05). CONCLUSIONS: Over the past 7.5 years, except during the COVID-19 pandemic, EEN usage rates have not changed despite an increase in biologic use, although combination induction is an emerging trend.

Development and Validation of the Glasgow Exclusive Enteral Nutrition Index of Compliance.

BACKGROUND AND AIMS: Treatment adherence is key to the efficacy of exclusive enteral nutrition [100% EN] in active Crohn's disease [CD], but there are no biomarkers to objectively estimate this. We explored faecal parameters as biomarkers of compliance with 100% EN, and subsequently developed and validated the Glasgow Exclusive Enteral Nutrition Index of Compliance [GENIE]. METHODS: Healthy adults replaced all [100% EN] or part [85% EN, 50% EN, 20% EN] of their diet with a formula for 7 days. Faecal pH, water content, short chain fatty acids, and branched chain fatty acids [BCFAs] were measured before [D0] and after [D7] each intervention. Optimal biomarkers and threshold values were derived using receiver operating characteristic curve analyses and machine learning to develop the GENIE. The GENIE was then validated in 30 CD children, during and after 100% EN. RESULTS: In all, 61 adults were recruited. D7 faecal pH and the ratios of BCFAs to either acetate or butyrate performed the best to differentiate between patients on 100% EN from <100% EN. Two models were generated; one included faecal metabolites (Laboratory GENIE, L-GENIE; sensitivity, specificity, and positive predictive value [PPV] of 88%, 94%, and 92%) and a second one [Clinical Genie, C-GENIE] which considers only faecal pH [sensitivity, specificity, and PPV of 84%, 86%, and 81%]. Validation of GENIE in CD children found that C-GENIE outperformed L-GENIE, producing a sensitivity, specificity, and PPV of 85%, 88%, and 88%, respectively. CONCLUSIONS: GENIE can help predict adherence to 100% EN and may complement current conventional dietary assessment.

An Optimised Monophasic Faecal Extraction Method for LC-MS Analysis and Its Application in Gastrointestinal Disease.

Liquid chromatography coupled with mass spectrometry (LC-MS) metabolomic approaches are widely used to investigate underlying pathogenesis of gastrointestinal disease and mechanism of action of treatments. However, there is an unmet requirement to assess faecal metabolite extraction methods for large-scale metabolomics studies. Current methods often rely on biphasic extractions using harmful halogenated solvents, making automation and large-scale studies challenging. The present study reports an optimised monophasic faecal extraction protocol that is suitable for untargeted and targeted LC-MS analyses. The impact of several experimental parameters, including sample weight, extraction solvent, cellular disruption method, and sample-to-solvent ratio, were investigated. It is suggested that a 50 mg freeze-dried faecal sample should be used in a methanol extraction (1:20) using bead beating as the means of cell disruption. This is revealed by a significant increase in number of metabolites detected, improved signal intensity, and wide metabolic coverage given by each of the above extraction parameters. Finally, we addressed the applicability of the method on faecal samples from patients with Crohn's disease (CD) and coeliac disease (CoD), two distinct chronic gastrointestinal diseases involving metabolic perturbations. Untargeted and targeted metabolomic analysis demonstrated the ability of the developed method to detect and stratify metabolites extracted from patient groups and healthy controls (HC), highlighting characteristic changes in the faecal metabolome according to disease. The method developed is, therefore, suitable for the analysis of patients with gastrointestinal disease and can be used to detect and distinguish differences in the metabolomes of CD, CoD, and HC.

The inexorable increase of biologic exposure in paediatric inflammatory bowel disease: a Scottish, population-based, longitudinal study.

BACKGROUND: The use of biologics in paediatric-onset inflammatory bowel disease (PIBD) is rapidly changing. AIMS: To identify the incidence and prevalence of biologic use within Scottish PIBD services, and to describe patient demographics and outcomes for those patients who required escalation of therapy beyond anti-tumour necrosis factor alpha (anti-TNFα) agents METHODS: We captured a nationwide cohort of prospectively identified patients less than 18 years of age with PIBD (A1 phenotype; diagnosed <17 years of age) within paediatric services over a 4.5-year period (1 January 2015-30 June 2019). All patients who received infliximab, adalimumab, vedolizumab or ustekinumab during the study period and/or received their first dose of these biologics were audited retrospectively. RESULTS: Scotland-wide PIBD-prevalence cases increased from 554 to 644 over the study period. A total of 495 incident new-start biological therapies were commenced on 403 PIBD patients: 295 infliximab (60%), 161 adalimumab (32%), 24 vedolizumab (5%) and 15 ustekunumab (3%). The proportion of new-start biologics changed with infliximab initiation rates decreasing (87%-54%) while adalimumab (13%-31%), vedolizumab (0%-9%) and ustekinumab (0%-6%) all increased. The incidence rate (first dose of new biologic not including biosimilar switch) increased from 6.9% to 8.1% over the study period and point prevalence rates (any biologic use) increased from 20.2% to 43.5% - an average annual percentage increase of 20%. Biosimilar penetration of new-start anti-TNFα agents increased from 3% to 91%. Demographics and outcomes of those patients receiving vedolizumab and ustekinumab were similar. CONCLUSIONS: Complete accrual of Scottish nationwide biologic usage within paediatric services demonstrates a rapidly changing, inexorably increasing PIBD biologics landscape.

Optimized Infliximab Induction Predicts Better Long-Term Clinical and Biomarker Outcomes Compared to Standard Induction Dosing.

OBJECTIVES: To evaluate the efficacy of standard and optimized infliximab induction dosing in attaining corticosteroid (CS) free clinical remission at week 52 and the effect that post-induction trough levels have on long-term outcome. METHODS: Inflammatory bowel disease (IBD) patients ≤18 years commenced on infliximab between August 1, 2016, and August 1, 2018, from Vancouver, Canada, and Glasgow, Scotland, were included. The Glasgow cohort followed standard induction while the Vancouver cohort undertook induction optimization based on clinical, biomarker, and proactive infliximab trough levels. Baseline characteristics and laboratory values were documented. RESULTS: In total, 140 children were included [median age 14.1 years (interquartile range (IQR) 12.0-16.0)]; 54% male. CS-free clinical remission at week 52 was higher in the optimized group compared to the standard cohort [65/78 (83%) vs. 32/62 (52%), P < 0.001]. Combined CS-free clinical and biomarker remission (CRP < 5 mg/L) was also higher in the optimized compared to the standard cohort [65/78 (83%) vs 25/62 (40%), P < 0.001]. The median post-induction trough level was higher in children who were in CS-free clinical remission at week 52 [3.6 mg/L (1.5-7.1)] vs. those who were not [2.0 mg/L (0.8-4.1), P = 0.04]. The odds of attaining a therapeutic post-induction trough level were almost 4-fold higher in the optimized group than the standard cohort (OR 3.97, 95% CI: 1.89-8.68, P < 0.001). CONCLUSIONS: Standard infliximab induction resulted in less favorable long-term outcomes for pediatric IBD patients. Optimizing induction using clinical, biomarker, and proactive trough levels resulted in higher post-induction trough levels and a greater odds of attaining long-term clinical remission.

Implications for sequencing of biologic therapy and choice of second anti-TNF in patients with inflammatory bowel disease: results from the IMmunogenicity to Second Anti-TNF therapy (IMSAT) therapeutic drug monitoring study.

BACKGROUND: Anti-drug antibodies are associated with treatment failure to anti-TNF agents in patients with inflammatory bowel disease (IBD). AIM: To assess whether immunogenicity to a patient's first anti-TNF agent would be associated with immunogenicity to the second, irrespective of drug sequence METHODS: We conducted a UK-wide, multicentre, retrospective cohort study to report rates of immunogenicity and treatment failure of second anti-TNF therapies in 1058 patients with IBD who underwent therapeutic drug monitoring for both infliximab and adalimumab. The primary outcome was immunogenicity to the second anti-TNF agent, defined at any timepoint as an anti-TNF antibody concentration ≥9 AU/ml for infliximab and ≥6 AU/ml for adalimumab. RESULTS: In patients treated with infliximab and then adalimumab, those who developed antibodies to infliximab were more likely to develop antibodies to adalimumab, than patients who did not develop antibodies to infliximab (OR 1.99, 95%CI 1.27-3.20, p = 0.002). Similarly, in patients treated with adalimumab and then infliximab, immunogenicity to adalimumab was associated with subsequent immunogenicity to infliximab (OR 2.63, 95%CI 1.46-4.80, p < 0.001). For each 10-fold increase in anti-infliximab and anti-adalimumab antibody concentration, the odds of subsequently developing antibodies to adalimumab and infliximab increased by 1.73 (95% CI 1.38-2.17, p < 0.001) and 1.99 (95%CI 1.34-2.99, p < 0.001), respectively. Patients who developed immunogenicity with undetectable drug levels to infliximab were more likely to develop immunogenicity with undetectable drug levels to adalimumab (OR 2.37, 95% CI 1.39-4.19, p < 0.001). Commencing an immunomodulator at the time of switching to the second anti-TNF was associated with improved drug persistence in patients with immunogenic, but not pharmacodynamic failure. CONCLUSION: Irrespective of drug sequence, immunogenicity to the first anti-TNF agent was associated with immunogenicity to the second, which was mitigated by the introduction of an immunomodulator in patients with immunogenic, but not pharmacodynamic treatment failure.

Intestinal fatty acid binding protein is a disease biomarker in paediatric coeliac disease and Crohn's disease.

BACKGROUND: There is a clinical need to develop biomarkers of small bowel damage in coeliac disease and Crohn's disease. This study evaluated intestinal fatty acid binding protein (iFABP), a potential biomarker of small bowel damage, in children with coeliac disease and Crohn's disease. METHODS: The concentration iFABP was measured in plasma and urine of children with ulcerative colitis, coeliac disease, and Crohn's disease at diagnosis and from the latter two groups after treatment with gluten free diet (GFD) or exclusive enteral nutrition (EEN), respectively. Healthy children (Controls) were also recruited. RESULTS: 138 children were recruited. Plasma but not urinary iFABP was higher in patients with newly diagnosed coeliac disease than Controls (median [Q1, Q3] coeliac disease: 2104 pg/mL 1493, 2457] vs Controls: 938 pg/mL [616, 1140], p = 0.001). Plasma or urinary iFABP did not differ between patients with coeliac on GFD and Controls. Baseline iFABP in plasma decreased by 6 months on GFD (6mo GFD: 1238 pg/mL [952, 1618], p = 0.045). By 12 months this effect was lost, at which point 25% of patients with coeliac disease had detectable gluten in faeces, whilst tissue transglutaminase IgA antibodies (TGA) continued to decrease. At diagnosis, patients with Crohn's disease had higher plasma iFABP levels than Controls (EEN Start: 1339 pg/mL [895, 1969] vs Controls: 938 pg/mL [616, 1140], p = 0.008). iFABP did not differ according to Crohn's disease phenotype. Induction treatment with EEN tended to decrease (p = 0.072) iFABP in plasma which was no longer different to Controls (EEN End: 1114 pg/mL [689, 1400] vs Controls: 938 pg/mL [616, 1140], p = 0.164). Plasma or urinary iFABP did not differ in patients with ulcerative colitis from Controls (plasma iFABP, ulcerative colitis: 1309 pg/mL [1005, 1458] vs Controls: 938 pg/mL [616, 1140], p = 0.301; urinary iFABP ulcerative colitis: 38 pg/mg [29, 81] vs Controls: 53 pg/mg [27, 109], p = 0.605). CONCLUSIONS: Plasma, but not urinary iFABP is a candidate biomarker with better fidelity in monitoring compliance during GFD than TGA. The role of plasma iFABP in Crohn's disease is promising but warrants further investigation. TRIAL REGISTRATION: Clinical Trials.gov, NCT02341248. Registered on 19/01/2015.

Thromboprophylaxis Use in Paediatric Inflammatory Bowel Disease: An International RAND Appropriateness Panel.

BACKGROUND AND AIMS: Thromboprophylaxis use in paediatric inflammatory bowel disease [IBD] is inconsistent. Current guidelines only support treating children with acute severe colitis with risk factors. We convened an international RAND panel to explore thromboprophylaxis in paediatric IBD inpatients in the context of new evidence. METHODS: We convened a geographically diverse 14-person panel of paediatric gastroenterologists alongside supporting experts. An online survey was sent before an online meeting. Panellists were asked to rate the appropriateness of thromboprophylaxis in hospitalised paediatric IBD patients via 27 scenarios of varying ages, gender, and phenotype, with and without thrombotic risk factors. Anonymised results were presented at the meeting. A second modified survey was distributed to all panellists present at the meeting. Results from the second survey constitute the RAND panel results. The validated RAND disagreement index defined disagreement when ≥ 1. RESULTS: The combined outcome of thromboprophylaxis being considered appropriate until discharge and inappropriate to withhold was seen in 20 of 27 scenarios, including: all patients with new-onset acute severe colitis; all flares of known ulcerative colitis, irrespective of risk factors except in pre-pubescent patients with limited disease and no risk factors; and all Crohn's patients with risk factors. Disagreement was seen in five scenarios regarding Crohn's without risk factors, where outcomes were already uncertain. CONCLUSIONS: RAND panels are an established method to assess expert opinion in areas of limited evidence. This work therefore constitutes neither a guideline nor a consensus; however, the findings suggest a need to re-evaluate the role of thromboprophylaxis in future guidelines.

The Effects of Commonly Consumed Dietary Fibres on the Gut Microbiome and Its Fibre Fermentative Capacity in Adults with Inflammatory Bowel Disease in Remission.

Introduction: It has been suggested that the gut microbiome of patients with inflammatory bowel disease (IBD) is unable to ferment dietary fibre. This project explored the in vitro effect of fibre fermentation on production of short-chain fatty acids (SCFA) and on microbiome composition. Methods: Faecal samples were collected from 40 adults (>16 y) with IBD (n = 20 with Crohn's disease and n = 20 with ulcerative colitis) in clinical remission and 20 healthy controls (HC). In vitro batch culture fermentations were carried out using as substrates maize starch, apple pectin, raftilose, wheat bran, α cellulose and a mixture of these five fibres. SCFA concentration (umol/g) was quantified with gas chromatography and microbiome was profiled with 16S rRNA sequencing. Results: Fibre fermentation did not correct the baseline microbial dysbiosis or lower diversity seen in either patients with CD or UC. For all fibres, up to 51% of baseline ASVs or genera changed in abundance in HC. In patients with IBD, fermentation of fibre substrates had no effect on species or genera abundance. Production of SCFA varied among the different fibre substrates but this was not different between the two IBD groups and compared to HC after either 5 or 24 h fermentation. Conclusions: Despite extensive microbial dysbiosis, patients with IBD have a similar capacity to ferment fibre and release SCFA as HC. Fibre supplementation alone may be unlikely to restore to a healthy status the compositional shifts characteristic of the IBD microbiome.

Automated iterative Csp3-C bond formation.

Fully automated synthetic chemistry would substantially change the field by providing broad on-demand access to small molecules. However, the reactions that can be run autonomously are still limited. Automating the stereospecific assembly of Csp3-C bonds would expand access to many important types of functional organic molecules1. Previously, methyliminodiacetic acid (MIDA) boronates were used to orchestrate the formation of Csp2-Csp2 bonds and were effective building blocks for automating the synthesis of many small molecules2, but they are incompatible with stereospecific Csp3-Csp2 and Csp3-Csp3 bond-forming reactions3-10. Here we report that hyperconjugative and steric tuning provide a new class of tetramethyl N-methyliminodiacetic acid (TIDA) boronates that are stable to these conditions. Charge density analysis11-13 revealed that redistribution of electron density increases covalency of the N-B bond and thereby attenuates its hydrolysis. Complementary steric shielding of carbonyl π-faces decreases reactivity towards nucleophilic reagents. The unique features of the iminodiacetic acid cage2, which are essential for generalized automated synthesis, are retained by TIDA boronates. This enabled Csp3 boronate building blocks to be assembled using automated synthesis, including the preparation of natural products through automated stereospecific Csp3-Csp2 and Csp3-Csp3 bond formation. These findings will enable increasingly complex Csp3-rich small molecules to be accessed via automated assembly.

Primary Care Physicians', Psychiatrists', and Oncologists' Coordination While Prescribing Medications for Patients With Multiple Chronic Conditions.

OBJECTIVES: Coordination of medication prescribing is important in the care of patients with multiple chronic conditions (MCC) given the involvement of multiple providers and multiple medications used to manage MCC. The objective of this study was to identify physician and practice factors associated with physicians' coordination of prescribing for complex patients with MCC. METHODS: Our cross-sectional study used a 33-item anonymous, online survey to assess physicians' coordination practices while prescribing for patients with MCC. We sampled primary care physicians (PCPs), psychiatrists, and oncologists across the United States. Coordination of medication prescribing was measured on a 7-point Likert-type scale. χ2, Fisher exact test, and binomial logistic regression, adjusted for factors and covariates, were used to determine differences in coordination of prescribing. Average marginal effects were calculated for factors. RESULTS: A total of 50 PCPs, 50 psychiatrists, and 50 oncologists participated. Most psychiatrists (56%) and oncologists (52%) reported frequently coordinating prescribing with other physicians, whereas less than half of the PCPs (42%) reported frequently coordinating prescribing. Female physicians were 25% points more likely to report coordinating prescribing than male physicians (P = 0.0186), and physicians not using electronic medical records were 30% points more likely to report coordinating prescribing than physicians using electronic medical records (P = 0.0230). Four additional factors were associated with lower likelihood of coordinating prescribing. CONCLUSIONS: Physician and practice factors may influence differences in coordination of medication prescribing, despite physician specialty. These factors can provide a foundation for developing interventions to improve coordination of prescribing practices for MCC.

The Impact of Compliance During Exclusive Enteral Nutrition on Faecal Calprotectin in Children With Crohn Disease.

ABSTRACT: It remains unclear whether suboptimal response to exclusive enteral nutrition (EEN) in some children with Crohn disease (CD) is explained by poor compliance. The present study measured faecal gluten immunogenic peptides (GIP), a biomarker of gluten intake, in 45 children (3- 17 years) with CD, and explored associations with faecal calprotectin (FC) levels at 33 and 54 days of EEN. FC decreased in patients with undetectable GIP at both 33 and 54 days of EEN (mean decrease, 33 days: -743 mg/kg, 54 days: -1043 mg/kg, P  < 0.001) but not in patients who had detectable levels. At EEN completion, patients with undetectable GIP had a lower FC by 717 mg/kg compared with patients with a positive GIP result (P = 0.042) and demonstrated a greater decline from baseline FC (-69% vs +5%, P = 0.011). Poorer response to EEN is explained in part by diminished compliance. Faecal GIP might be useful as proxy biomarker of EEN compliance.