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.

Development, Validation, and Evaluation of the Pediatric Inflammatory Crohn's Magnetic Resonance Enterography Index From the ImageKids Study.

BACKGROUND & AIMS: Cross-sectional imaging is important in the assessment of transmural inflammation in Crohn's disease (CD). Small bowel involvement is often more extensive in pediatric CD, requiring a panentering measuring tool. We undertook to develop a magnetic resonance enterography (MRE)-based index that would measure inflammation in all segments of the intestine, without rectal contrast. METHODS: Children with CD underwent ileocolonoscopy and MRE and half were prospectively followed for 18 months when MRE was repeated. Item generation and reduction were performed by a Delphi panel of pediatric radiologists, a systematic literature review, a cross-sectional study of 48 MREs, and a steering committee. Formatting and weighting were performed using multivariate modeling adjusted by a steering committee. MREs were read locally and centrally. Reliability, validity, and responsiveness were determined using several clinimetric and psychometric approaches. RESULTS: Thirty items were initially generated and reduced to 5 using regression analysis on 159 MREs: wall thickness, wall diffusion weighted imaging, ulcerations, mesenteric edema, and comb sign. In the validation cohort of 81 MREs, the weighted global PICMI correlated well with the radiologist global assessment (r = 0.85; P < .001) and with the simple endoscopic score in a subsample with ileocolonic disease (r = 0.63; P < .001). Interobserver and test-retest reliability were high (interclass correlation coefficients, 0.84; 95% confidence interval [CI], 0.79-0.87; and 0.81, 95% CI, 0.65-0.90, respectively; both P < .001). Excellent responsiveness was found at repeated visits (n = 116 MREs; area under the receiver operating characteristic curve 0.96; 95% CI, 0.93-0.99). Transmural healing was defined as PICMI ≤10 and response as a change of >20 points with excellent discriminative validity (area under the receiver operating characteristic curve = 0.96; 95% CI, 0.93-0.99). CONCLUSIONS: The PICMI is a valid, reliable, and responsive index for assessing transmural inflammation in pediatric CD. It scores the entire bowel length and does not require intravenous contrast or rectal enema and, therefore, is suitable for use in children. (ClinicalTrials.gov, Number: NCT01881490.).

Development of age-dependent micronutrient centile charts and their utility in children with chronic gastrointestinal conditions at risk of deficiencies: A proof-of-concept study.

BACKGROUND & AIMS: Interpretation of blood micronutrient levels requires age-appropriate reference intervals. This study developed age-dependent micronutrient centiles for healthy children (HC) and explored their utility in sick children. METHODS: 244 blood samples were collected from normal HC who underwent tests for acute illness. Age-dependent, centile charts were fitted for zinc, copper, magnesium and selenium in plasma and erythrocytes (RBC), and for vitamins B1, B2 and B6 in RBC. For 34 children with Crohn's disease (CrD) and 55 with coeliac disease (CoeD), Z-scores for the levels of these micronutrients were computed, using the new charts. Associations were explored between plasma and RBC micronutrient Z-scores, and in CrD with CRP and serum albumin. RESULTS: In HC, plasma zinc and selenium increased and plasma copper, magnesium and RBC vitamins B1, B2 and B6 decreased with age. In HC and in CrD, plasma and RBC Z-scores for copper, selenium and magnesium (all p < 0.001) were positively correlated, but not for zinc. In CrD, albumin was related with plasma zinc (rho = 0.62; p < 0.001) and selenium Z-scores (rho = 0.65; p < 0.001) and plasma copper Z-score with CRP (rho = 0.45; p = 0.02). A higher proportion of CrD children had low levels for B2 (21% vs 0%; p = 0.01) and B6 (18% vs 0%; p = 0.02) using the new centile charts than the local laboratory references. CONCLUSION: Age-dependent micronutrient centile charts enable tracking of micronutrient status, Z-score calculation and may prevent misdiagnosis and inappropriate treatment of deficiencies. In systemic inflammatory conditions, RBC measurements of certain micronutrients may be more reliable to use than measurements in plasma.

Micronutrient deficiencies in children with coeliac disease; a double-edged sword of both untreated disease and treatment with gluten-free diet.

INTRODUCTION: In coeliac disease (CD) micronutrient deficiencies may occur due to malabsorption in active disease and diminished intake during treatment with a gluten-free diet (GFD). This study assessed the micronutrient status in children with CD at diagnosis and follow-up. METHODS: Fifteen micronutrients were analysed in 106 blood samples from newly diagnosed CD and from patients on a GFD for <6 months, 6-12 months and with longstanding disease (>12 months). Predictors of micronutrient status included: demographics, disease duration, anthropometry, gastrointestinal symptoms, raised tissue transglutaminase antibodies (TGA), multivitamin use and faecal gluten immunogenic peptide (GIP). Micronutrient levels were compared against laboratory reference values. RESULTS: At CD diagnosis (n = 25), low levels in ≥10% of patients were observed for: vitamins E (88%), B1 (71%), D (24%), K (21%), A (20%) and B6 (12%), ferritin (79%), and zinc (33%). One year post-diagnosis, repletion of vitamins E, K, B6 and B1 was observed (<10% patients). In contrast, deficiencies for vitamins D, A and zinc did not change significantly post-diagnosis. Copper, selenium and magnesium did not differ significantly between diagnosis and follow-up. All samples for B2, folate, vitamin C (except for one sample) and B12 were normal. A raised TGA at follow-up was associated with low vitamins A and B1 (raised vs normal TGA; vitamin A: 40% vs 17%, p = 0.044, vitamin B1: 37% vs 13%, p = 0.028). Low vitamin A (p = 0.009) and vitamin D (p = 0.001) were more common in samples collected during winter. There were no associations between micronutrient status with GIP, body mass index, height, socioeconomic status, or gastrointestinal symptom. Multivitamin use was less common in patients with low vitamin D. CONCLUSIONS: Several micronutrient deficiencies in CD respond to a GFD but others need to be monitored long-term and supplemented where indicated.

Ferric Carboxymaltose Across All Ages in Paediatric Gastroenterology Shows Efficacy Without Increased Safety Concerns.

OBJECTIVES: The aim of the study was to assess the efficacy, safety and side-effect profile of ferric carboxymaltose (FCM) for correcting IDA in children and adolescents in paediatric gastroenterology, hepatology, and nutrition. METHOD: This was a retrospective study of all gastroenterology patients <18 years who had FCM (October 2015 to October 2017). Haematological and biochemical parameters were recorded pre-infusion, at 4 weeks, 3 months, 6 months, and 1 year post-infusion. Recognised side-effects were documented. RESULTS: Sixty-six children received FCM during this period. Data was analysed on 61 children, 5 excluded because of inadequate data. The median age at administration was 14 years (IQR 7). Thirty-two (52%) were boys. Twenty-six (42%) were <14 years old. Seven (11.5%) were <5 years old. Seventeen (28%) were switched from oral iron supplements to FCM. The median dose of FCM delivered was 19 mg/kg. The median haemoglobin increased from 108 to 126 g/L at 1 month post-infusion (P value <0.00001). The mean cell volume also improved from 80 to 84 fL at 1 month post-infusion (P value = 0.0007). Forty-eight (94%) children corrected their anaemia after receiving FCM. Two patients (3%) reported side-effects with skin bruising and staining. CONCLUSIONS: FCM appears to be effective in correcting IDA in children across a wide range of gastroenterology indications and all ages. It is effective and generally well tolerated including in very young patients. Potential side-effects can be avoided by careful monitoring during infusions.

Analysis of 61 exclusive enteral nutrition formulas used in the management of active Crohn's disease-new insights into dietary disease triggers.

BACKGROUND: Exclusive enteral nutrition (EEN) is an effective treatment for Crohn's disease. AIMS: To investigate the hypothesis that ingredients of EEN formulas are unlikely to initiate a disease flare and that their dietary elimination is not essential for disease amelioration. METHODS: We performed compositional analysis of EEN formulas with evidence of efficacy in management of active Crohn's disease. Macronutrient content was compared against the dietary reference values (DRV), the UK National Diet and Nutrition Survey (NDNS) and intake of Crohn's disease children. Food additives were cross-referenced against the FAO/WHO database. RESULTS: Sixty-one formulas were identified with variable composition (carbohydrates [22.8%-89.3%], protein [7.8%-30.1%], fat [0%-52.5%]). Maltodextrin, milk protein and vegetable/plant oils were the commonest macronutrient sources. Their n-6:n-3 fatty acid ratio varied from 0.25 to 46.5. 56 food additives were identified (median per formula: 11). All formulas were lactose-free, gluten-free, and 82% lacked fibre. The commonest food additives were emulsifiers, stabilisers, antioxidants, acidity regulators and thickeners. Food additives, implicated in Crohn's disease aetiology, were present in formulas (modified starches [100%], carrageenan [22%], carboxymethyl cellulose [13%] and polysorbate 80 [5%]). Remission rates did not differ between EEN formulas with and without those food additives. Analysis including only formulas from randomised controlled trials (RCTs) retained in the latest Cochrane meta-analysis produced similar findings. EEN formulas contained less energy from saturated fat than NDNS intake. CONCLUSION: We have identified food ingredients which are present in EEN formulas that are effective in Crohn's disease and challenge perceptions that these ingredients might be harmful.

A Double-Blind, Placebo-Controlled Trial to Assess Safety and Tolerability of (Thetanix) Bacteroides thetaiotaomicron in Adolescent Crohn's Disease.

INTRODUCTION: Thetanix (gastroresistant capsules containing lyophilized Bacteroides thetaiotaomicron) is a live biotherapeutic, under development for Crohn's disease, that antagonizes transcription factor nuclear factor kappa B, reducing proinflammatory cytokines, particularly tumor necrosis factor alpha. We aimed to assess safety and tolerability in adolescents with Crohn's disease in remission. METHODS: Subjects who were 16-18 years with Crohn's in remission (weighted pediatric Crohn's disease activity index <12.5) were recruited. Each active dose comprised ∼108.2±1.4 colony forming units of B. thetaiotaomicron (randomized 4:1 active:placebo). Part A was single dose. Part B involved 7.5 days twice daily dosing. Serial stools were analyzed for calprotectin, 16S rRNA sequencing, and B. thetaiotaomicron real-time polymerase chain reaction. Bloods were taken serially. Subjects reported adverse events and recorded temperature twice daily. RESULTS: Fifteen subjects were treated-8 in part A (75% men, median 17.1 years) and 10 in part B, including 3 from part A (80% men, median 17.1 years); all 18 completed. Seventy percent took concurrent immunosuppression. Reported compliance was >99% in part B. Two subjects reported adverse events deemed related-one in part A with eructation, flatulence, and reflux; one in part B with dizziness, abdominal pain, and headache. No serious adverse events were reported. There was no significant change in median calprotectin across part B (87.8 [4.4-447] to 50.5 [5.3-572], P = 0.44 by the Fisher exact test in the active group). No significant differences were found in microbiota profiles, but diversity seemed to increase in treated subjects. DISCUSSION: Thetanix, after single and multiple doses, was well tolerated. Although the numbers in this study were small, the safety profile seems good. Future studies should explore efficacy.

Treatment of Active Crohn's Disease With an Ordinary Food-based Diet That Replicates Exclusive Enteral Nutrition.

BACKGROUND & AIMS: Exclusive enteral nutrition (EEN) is the only established dietary treatment for Crohn's disease (CD), but its acceptability is limited. There is a need for novel dietary treatments for CD. METHODS: We evaluated the effects of an individualized food-based diet (CD-TREAT), with similar composition to EEN, on the gut microbiome, inflammation, and clinical response in a rat model, healthy adults, and children with relapsing CD. Twenty-five healthy adults randomly received EEN or CD-TREAT for 7 days, followed by a 14-day washout period, followed by the alternate diet. Fecal microbiome and metabolome were assessed before and after each diet. HLA-B7 and HLA-B27 transgenic rats with gut inflammation received EEN, CD-TREAT, or standard chow for 4 weeks. Fecal, luminal, and tissue microbiome, fecal metabolites, and gut inflammation were assessed. Five children with active CD activity received CD-TREAT and their clinical activity and calprotectin were evaluated after 8 weeks of treatment. RESULTS: For healthy adults, CD-TREAT was easier to comply with and more acceptable than EEN. CD-TREAT induced similar effects to EEN (EEN vs CD-TREAT) on fecal microbiome composition, metabolome, mean total sulfide (increase 133.0 ± 80.5 vs 54.3 ± 47.0 nmol/g), pH (increase 1.3 ± 0.5 vs 0.9 ± 0.6), and the short-chain fatty acids (µmol/g) acetate (decrease 27.4 ± 22.6 vs 21.6 ± 20.4), propionate (decrease 5.7 ± 7.8 vs 5.2 ± 7.9), and butyrate (decrease 7.0 ± 7.4 vs 10.2 ± 8.5). In the rat model, CD-TREAT and EEN produced similar changes in bacterial load (decrease 0.3 ± 0.3 log10 16S rRNA gene copies per gram), short-chain fatty acids, microbiome, and ileitis severity (mean histopathology score decreases of 1.25 for EEN [P = .015] and 1.0 for CD-TREAT [P = .044] vs chow). In children receiving CD-TREAT, 4 (80%) had a clinical response and 3 (60%) entered remission, with significant concurrent decreases in fecal calprotectin (mean decrease 918 ± 555 mg/kg; P = .002). CONCLUSION: CD-TREAT replicates EEN changes in the microbiome, decreases gut inflammation, is well tolerated, and is potentially effective in patients with active CD. ClinicalTrials.gov, numbers NCT02426567 and NCT03171246.

Untargeted Metabolomics of Extracts from Faecal Samples Demonstrates Distinct Differences between Paediatric Crohn's Disease Patients and Healthy Controls but No Significant Changes Resulting from Exclusive Enteral Nutrition Treatment.

Metabolomic profiling using high resolution mass spectrometry with hydrophilic interaction chromatography was applied to 11 faecal extracts from eleven healthy children and to 43 faecal extracts from eleven children undergoing exclusive enteral nutrition for the treatment of active Crohn's disease (CD) at timepoints before, during (15, 30, and 60 days), and after treatment. Differences between the control and CD samples were identified at each timepoint. An orthogonal partial least square-discriminant analysis (OPLS-DA) model identified eight metabolites that were normally distributed according to Q-Q plots. The OPLS-DA model was able to discriminate the CD samples from the controls at every timepoint, but the model was not able to differentiate the CD samples from one another at the different timepoints during treatment with exclusive enteral nutrition. The differentiated metabolites identified in the CD samples included tyrosine, an ornithine isomer, arachidonic acid, eicosatrienoic acid, docosatetraenoic acid, a sphingomyelin, a ceramide, and dimethylsphinganine. Despite successful treatment, underlying differences remained in the metabolome of the CD patients. These differences dominated the separation of the samples when multivariate methods were applied.

Differences in Outcomes Over Time With Exclusive Enteral Nutrition Compared With Steroids in Children With Mild to Moderate Crohn's Disease: Results From the GROWTH CD Study.

BACKGROUND: Exclusive enteral nutrition [EEN] and corticosteroids [CS] induce similar rates of remission in mild to moderate paediatric Crohn's disease [CD], but differ with regard to mucosal healing. Our goal was to evaluate if EEN at diagnosis was superior to CS for improving long-term outcomes. METHODS: We prospectively followed newly diagnosed children aged < 17 years, with mild to moderate CD at baseline, for 2 years in the GROWTH CD study. Patients were evaluated at baseline and at 8, 12, 78, and 104 weeks. Remission, relapses, complications [fibrostenotic disease, penetrating disease, and active perianal disease] and growth were recorded throughout the study. A propensity score analysis was performed. RESULTS: A total of 147 children [mean age 12.9 ± 3.2 years], treated by EEN [n = 60] or CS [n = 87] were included. New complications developed in 13.7% of CS [12/87] versus 11.6% of EEN [7/60], p = 0.29. Remission was achieved in 41/87 [47%] in CS and 38/60 [63%] EEN, p = 0.036. Median time to relapse did not differ [14.4 ± 1 months with CS, 16.05 ± 1.1 EEN, p = 0.28]. Mean height Z scores decreased from Week 0 to Week 78 with CS [-0.34 ± 1.1 to -0.51 ± 1.2, p = 0.01], but not with EEN [-0.32 ± 1.1 to -0.22 ± 0.9, p = 0.56]. In a propensity score analysis, EEN was superior to CS for inducing remission [p = 0.05] and trended to superiority for height Z score [p = 0.055]. CONCLUSIONS: Use of EEN was associated with higher remission rates and a trend toward better growth but with similar relapse and complication rates in new-onset mild to moderate paediatric CD.

Quality Items Required for Running a Paediatric Inflammatory Bowel Disease Centre: An ECCO Paper.

BACKGROUND: The importance of a holistic approach with a comprehensive multidisciplinary team, including nutritional and psychosocial support, is becoming well recognised as a key contributor to optimal care in paediatric inflammatory bowel disease [IBD]. The Paediatric committee of ECCO [P-ECCO] aimed to determine important components that would contribute to quality of care in a paediatric IBD centre [henceforth 'quality items']. METHODS: First, a list of items has been generated by a Delphi group of 111 international paediatric IBD experts. Through an iterative process, the group graded and ranked the items according to their perceived relative contribution to quality care. We then surveyed 101 paediatric IBD centres affiliated with the Porto and Interest groups of ESPGHAN in Europe and with the ImproveCareNow registry in North America, exploring the availability of the retained items in their centres. RESULTS: A total of 68 items were generated and reduced to a list of 60 ranked order items, grouped in six domains: Facility, Personnel, Management, Supportive Services, Patient Support and Accessibility, and Academia and Communications. Of the retained items, 52 [88%] were present in most of the 101 high-performing paediatric IBD centres, and there was a trend for increased availability with increased patient volume at the centres. CONCLUSION: In this P-ECCO study, we attempted to tabulate, for the first time in paediatrics, 60 quality items that paediatric IBD referral centres may wish to include.

Dietary treatment of Crohn's disease: perceptions of families with children treated by exclusive enteral nutrition, a questionnaire survey.

BACKGROUND: Diet is strongly associated with the aetiology of Crohn's Disease (CD) and exclusive enteral nutrition (EEN) is the primary induction treatment in paediatric CD. This study explored opinions around the use of EEN and alternative novel, solid food-based diets (SFDs) expressed by paediatric patients with CD, previously treated with EEN and their parents. METHODS: This anonymous questionnaire surveyed families of CD patients treated with EEN over 1 year. Two questionnaire forms were completed; one asking the patients' opinions and another referring to their main carer. This questionnaire explored participants' demographic characteristics; acceptability of a repeat EEN course to treat a future flare (EEN repeat); their opinion on how difficult EEN would be compared to an example SFD; and their intention to participate in a future clinical trial assessing the therapeutic efficacy of an SFD in CD. RESULTS: Forty-one families of CD patients were approached with 29 sending replies (71%). Most of our participants were positive on completing another EEN course, however the majority would choose an SFD alternative (Patients:66, Parents:72%). Both patients and their parents rated EEN to be more difficult to adhere to compared to an example SFD (p < 0.05), and their ratings were strongly correlated (EEN:r = 0.83, SFD:r = 0.75, p < 0.001). The majority of our respondents would agree to participate in a clinical trial assessing an SFD's effectiveness (Patients:79, Parents:72%) for the management of active CD. CONCLUSIONS: While patients with CD and their families would accept an EEN repeat, the majority would prefer an SFD alternative. CD families surveyed are supportive of the development of solid food-based dietary treatments.

A retrospective study showing maintenance treatment options for paediatric CD in the first year following diagnosis after induction of remission with EEN: supplemental enteral nutrition is better than nothing!

BACKGROUND: A limited body of research suggests that ongoing maintenance enteral nutrition (MEN) can be beneficial in maintaining disease remission in Crohn's Disease (CD). We aimed to assess how achievable MEN is and whether it helps to prolong remission. METHODS: Patients newly diagnosed with CD in 2010 and 2011 who commenced exclusive enteral nutrition (EEN) for 8 weeks were followed up for a year post diagnosis. All patients who took EEN were encouraged to continue MEN post EEN. Data on azathioprine use was also collected. Categorical variables were compared using chi-square/Fischer's exact test. Medians were expressed along with complete data ranges. RESULTS: 59 patients (34 male, median age 11.07 years, range 2.5-16.33 years) were identified. 11/59 (18%) had a poor response to EEN and were switched to steroids. 48/59 patients completed 8 weeks EEN and achieved clinical remission/response. 46/48 patients received Modulen IBD®, 29/48 (60%) consumed EEN orally and 19/48 (40%) via NGT. 15/48 (31%) patients were able to continue MEN post EEN completion. MEN was consumed for a mean of 10.8 months (range 4-14 months). 14/15 patients drank MEN and 1/15 had MEN via NGT. Remission rates at 1 year in patients continuing MEN were 60% (9/15) compared to 15% (2/13) in patients taking no treatment (p = 0.001) and 65% (13/20) in patients taking azathioprine (p = 0.14). CONCLUSION: A sub group of patients can continue MEN as a maintenance treatment and this seems a useful strategy, especially in those who are not commencing azathioprine.

Nutritional therapy for the treatment of pediatric Crohn's disease.

Crohn's disease and ulcerative colitis are lifelong conditions with particular effects upon nutrition, especially in children and adolescents. Various therapies are available for these conditions but there remains no cure. Over the last decades, exclusive enteral nutrition (EEN) has been demonstrated to have efficacy in the induction of remission, along with numerous other nutritional and inflammatory benefits. This article reviews the benefits and outcomes associated with EEN in Crohn's disease. The potential mechanisms of this therapy are highlighted, along with factors that are barriers to the wider use of EEN.