Mechanisms and management of loss of response to anti-TNF therapy for patients with Crohn's disease: 3-year data from the prospective, multicentre PANTS cohort study

BACKGROUND

We sought to report the effectiveness of infliximab and adalimumab over the first 3 years of treatment and to define the factors that predict anti-TNF treatment failure and the strategies that prevent or mitigate loss of response.

METHODS

Personalised Anti-TNF therapy in Crohn's disease (PANTS) is a UK-wide, multicentre, prospective observational cohort study reporting the rates of effectiveness of infliximab and adalimumab in anti-TNF-naive patients with active luminal Crohn's disease aged 6 years and older. At the end of the first year, sites were invited to enrol participants still receiving study drug into the 2-year PANTS-extension study. We estimated rates of remission across the whole cohort at the end of years 1, 2, and 3 of the study using a modified survival technique with permutation testing. Multivariable regression and survival analyses were used to identify factors associated with loss of response in patients who had initially responded to anti-TNF therapy and with immunogenicity. Loss of response was defined in patients who initially responded to anti-TNF therapy at the end of induction and who subsequently developed symptomatic activity that warranted an escalation of steroid, immunomodulatory, or anti-TNF therapy, resectional surgery, or exit from study due to treatment failure. This study was registered with ClinicalTrials.gov, NCT03088449, and is now complete.

FINDINGS

Between March 19, 2014, and Sept 21, 2017, 389 (41%) of 955 patients treated with infliximab and 209 (32%) of 655 treated with adalimumab in the PANTS study entered the PANTS-extension study (median age 32·5 years [IQR 22·1-46·8], 307 [51%] of 598 were female, and 291 [49%] were male). The estimated proportion of patients in remission at the end of years 1, 2, and 3 were, for infliximab 40·2% (95% CI 36·7-43·7), 34·4% (29·9-39·0), and 34·7% (29·8-39·5), and for adalimumab 35·9% (95% CI 31·2-40·5), 32·9% (26·8-39·2), and 28·9% (21·9-36·3), respectively. Optimal drug concentrations at week 14 to predict remission at any later timepoints were 6·1-10·0 mg/L for infliximab and 10·1-12·0 mg/L for adalimumab. After excluding patients who had primary non-response, the estimated proportions of patients who had loss of response by years 1, 2, and 3 were, for infliximab 34·4% (95% CI 30·4-38·2), 54·5% (49·4-59·0), and 60·0% (54·1-65·2), and for adalimumab 32·1% (26·7-37·1), 47·2% (40·2-53·4), and 68·4% (50·9-79·7), respectively. In multivariable analysis, loss of response at year 2 and 3 for patients treated with infliximab and adalimumab was predicted by low anti-TNF drug concentrations at week 14 (infliximab: hazard ratio [HR] for each ten-fold increase in drug concentration 0·45 [95% CI 0·30-0·67], adalimumab: 0·39 [0·22-0·70]). For patients treated with infliximab, loss of response was also associated with female sex (vs male sex; HR 1·47 [95% CI 1·11-1·95]), obesity (vs not obese 1·62 [1·08-2·42]), baseline white cell count (1·06 [1·02-1·11) per 1 × 109 increase in cells per L), and thiopurine dose quartile. Among patients treated with adalimumab, carriage of the HLA-DQA1*05 risk variant was associated with loss of response (HR 1·95 [95% CI 1·17-3·25]). By the end of year 3, the estimated proportion of patients who developed anti-drug antibodies associated with undetectable drug concentrations was 44·0% (95% CI 38·1-49·4) among patients treated with infliximab and 20·3% (13·8-26·2) among those treated with adalimumab. The development of anti-drug antibodies associated with undetectable drug concentrations was significantly associated with treatment without concomitant immunomodulator use for both groups (HR for immunomodulator use: infliximab 0·40 [95% CI 0·31-0·52], adalimumab 0·42 [95% CI 0·24-0·75]), and with carriage of HLA-DQA1*05 risk variant for infliximab (HR for carriage of risk variant: infliximab 1·46 [1·13-1·88]) but not for adalimumab (HR 1·60 [0·92-2·77]). Concomitant use of an immunomodulator before or on the day of starting infliximab was associated with increased time without the development of anti-drug antibodies associated with undetectable drug concentrations compared with use of infliximab alone (HR 2·87 [95% CI 2·20-3·74]) or introduction of an immunomodulator after anti-TNF initiation (1·70 [1·11-2·59]). In years 2 and 3, 16 (4%) of 389 patients treated with infliximab and 11 (5%) of 209 treated with adalimumab had adverse events leading to treatment withdrawal. Nine (2%) patients treated with infliximab and two (1%) of those treated with adalimumab had serious infections in years 2 and 3.

INTERPRETATION

Only around a third of patients with active luminal Crohn's disease treated with an anti-TNF drug were in remission at the end of 3 years of treatment. Low drug concentrations at the end of the induction period predict loss of response by year 3 of treatment, suggesting higher drug concentrations during the first year of treatment, particularly during induction, might lead to better long-term outcomes. Anti-drug antibodies associated with undetectable drug concentrations of infliximab, but not adalimumab, can be predicted by carriage of HLA-DQA1*05 and mitigated by concomitant immunomodulator use for both drugs.

FUNDING

Guts UK, Crohn's and Colitis UK, Cure Crohn's Colitis, AbbVie, Merck Sharp and Dohme, Napp Pharmaceuticals, Pfizer, and Celltrion Healthcare.

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.

Impact of mental health comorbidity in children and young adults with inflammatory bowel disease: a UK population-based cohort study

OBJECTIVE

To evaluate the impact of mental health comorbidity in children and young adults with inflammatory bowel disease (IBD).

DESIGN

Retrospective observational study.

SETTING

Representative population, routinely collected primary care data from the UK Optimum Patient Care Research Database (2015-2019).

PARTICIPANTS

Patients with IBD aged 5-25 years with mental health conditions were compared with patients with IBD of the same age without mental health conditions.

PRIMARY AND SECONDARY OUTCOME MEASURES

Outcomes comprised quality-of-life indicators (low mood, self-harm, parasuicide, bowel symptoms, absence from school or work, unemployment, substance use and sleep disturbance), IBD interventions (medication, abdominal surgery, stoma formation and nutritional supplements) and healthcare utilisation (primary care interactions and hospital admissions).

RESULTS

Of 1943 individuals aged 5-25 years with IBD, 295 (15%) had a mental health comorbidity. Mental health comorbidity was associated with increased bowel symptoms (adjusted incident rate ratio (aIRR) 1.82; 95% CI 1.33 to 2.52), sleep disturbance (adjusted HR (aHR) 1.63; 95% CI 1.02 to 2.62), substance use (aHR 3.63; 95% CI 1.69 to 7.78), primary care interactions (aIRR 1.33; 95% CI 1.12 to 1.58) and hospital admissions (aIRR 1.87; 95%CI 1.29 to 2.75). In individuals ≥18 years old, mental health comorbidity was associated with increased time off work (aHR 1.55; 95% CI 1.21 to 1.99).

CONCLUSIONS

Mental health comorbidity in children and young adults with IBD is associated with poorer quality of life, higher healthcare utilisation and more time off work. It is imperative that affected young patients with IBD are monitored and receive early mental health support as part of their multidisciplinary care.

TRIAL REGISTRATION NUMBER

The study protocol was specified and registered a priori (ClinicalTrials.gov study identifier: NCT05206734).

Precision nutrition in pediatric IBD: A position paper from the ESPGHAN special interest group for basic science and translational research, the IBD Porto group, and allied health professionals

Stratified and precision nutrition refers to disease management or prevention of disease onset, based on dietary interventions tailored to a person's characteristics, biology, gut microbiome, and environmental exposures. Such treatment models may lead to more effective management of inflammatory bowel disease (IBD) and reduce risk of disease development. This societal position paper aimed to report advances made in stratified and precision nutritional therapy in IBD. Following a structured literature search, limited to human studies, we identified four relevant themes: (a) nutritional epidemiology for risk prediction of IBD development, (b) food-based dietary interventions in IBD, (c) exclusive enteral nutrition (EEN) for Crohn's disease (CD) management, and (d) pre- and probiotics for IBD management. There is scarce literature upon which we can make recommendations for precision or stratified dietary therapy for IBD, both for risk of disease development and disease management. Certain single-nucleotide polymorphisms related to polyunsaturated fatty acid (PUFA) metabolism may modify the effect dietary PUFA have in increasing the risk of IBD development. Non-colonic CD, mild-to-moderate CD, and high microbiota richness may predict success of EEN and may be used both for prediction of treatment continuation, but also for early cessation in nonresponders. There is currently insufficient evidence to make recommendations for precision or stratified dietary therapy for patients with established IBD. Despite the great interest in stratified and precision nutrition, we currently lack data to support conclusive recommendations. Replication of early findings by independent research groups and within structured clinical interventions is required.

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.

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.

The State of Clinical Trials in Pediatric Inflammatory Bowel Disease

The gap between available biologic and small molecule therapy for inflammatory bowel disease for children and adults remains large. At present only 2 anti-TNF agents are licensed for pediatric use compared with multiple other agents with different mechanisms of action being used in adults. The reasons are many but largely revolve around the inadequate acceptance of adult efficacy data to children, and the reluctance of industry to commit to early pediatric drug development for fear of inadequate return on investment. We suggest common sense steps that need to be taken to improve this situation.

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.

Children and Young Adults With Inflammatory Bowel Disease Have an Increased Incidence and Risk of Developing Mental Health Conditions: A UK Population-Based Cohort Study

BACKGROUND

The burden of mental health conditions in children and young adults with inflammatory bowel disease remains unclear. We assessed this using a primary care database in the United Kingdom.

METHODS

A retrospective, observational study compared children and young adults with incident inflammatory bowel disease 5 to 25 years of age (2010-2020) against population control subjects. Outcomes comprised incident depression, anxiety disorder, eating disorders, body image disorders, attention-deficit disorders, behavioral disorders, adjustment disorders, acute stress disorder, schizophrenia, bipolar disorder, posttraumatic stress disorder, self-harm, parasuicide (including suicide), and sleep disturbance. The any mental health condition category comprised any of these conditions.

RESULTS

A total of 3898 young patients with incident inflammatory bowel disease were matched to 15 571 control subjects. Inflammatory bowel disease patients were significantly more likely to develop new posttraumatic stress disorder (adjusted hazard ratio [aHR], 2.47; 95% confidence interval [CI], 1.23-4.94), eating disorders (aHR, 1.85; 95% CI, 1.05-3.26), self-harm (aHR, 1.49; 95% CI, 1.00-2.21), sleep disturbance (aHR, 1.40; 95% CI, 1.15-1.71), depression (aHR, 1.34; 95% CI, 1.16- 1.56), anxiety (aHR, 1.25; 95% CI, 1.06-1.48), and any mental health condition (aHR, 1.28; 95% CI, 1.12-1.46). Male inflammatory bowel disease patients aged 12 to 17 years, and patients with Crohn's disease appear to have the highest risk for developing new mental health conditions.

CONCLUSIONS

Young inflammatory bowel disease patients have a significantly higher incidence and risk of new mental health conditions. Mental health remains a critically overlooked aspect of inflammatory bowel disease patient management. Further research into identifying optimal monitoring tools and support for these patients is required to improve patient care. The study protocol was specified and registered a priori.ClinicalTrials.gov study identifier: NCT05206734.

Effectiveness of Switching to Subcutaneous Infliximab in Pediatric Inflammatory Bowel Disease Patients on Intravenous Maintenance Therapy

No real-world data are available on subcutaneous infliximab (SC-IFX) in pediatric inflammatory bowel disease (PIBD). We report a single-center cohort experience of an elective switching program from biosimilar intravenous infliximab to SC-IFX, 120 mg fortnightly, as maintenance. Clinical and laboratory data were collected for 7 patients with infliximab trough levels collected prior and at 6 and 40 weeks after the switch. High treatment persistence was registered with a single patient discontinuing the treatment due to high IFX antibodies, already present before switching. All patients remained in clinical remission with no significant changes in laboratory markers and median infliximab trough levels (12.3 µg/mL at baseline; 13.9 and 14.0 µg/mL at 6 and 40 weeks respectively). No newly-developed IFX antibodies were detected and no adverse reactions or rescue therapies were recorded. Our real-world data support the feasibility of an elective switch to SC-IFX in PIBD as maintenance with potential advantages concerning medical resources and patient satisfaction.

Genomic diagnosis and care co-ordination for monogenic inflammatory bowel disease in children and adults: consensus guideline on behalf of the British Society of Gastroenterology and British Society of Paediatric Gastroenterology, Hepatology and Nutrition

Genomic medicine enables the identification of patients with rare or ultra-rare monogenic forms of inflammatory bowel disease (IBD) and supports clinical decision making. Patients with monogenic IBD frequently experience extremely early onset of treatment-refractory disease, with complex extraintestinal disease typical of immunodeficiency. Since more than 100 monogenic disorders can present with IBD, new genetic disorders and variants are being discovered every year, and as phenotypic expression of the gene defects is variable, adaptive genomic technologies are required. Monogenic IBD has become a key area to establish the concept of precision medicine. Clear guidance and standardised, affordable applications of genomic technologies are needed to implement exome or genome sequencing in clinical practice. This joint British Society of Gastroenterology and British Society of Paediatric Gastroenterology, Hepatology and Nutrition guideline aims to ensure that testing resources are appropriately applied to maximise the benefit to patients on a national scale, minimise health-care disparities in accessing genomic technologies, and optimise resource use. We set out the structural requirements for genomic medicine as part of a multidisciplinary team approach. Initiation of genomic diagnostics should be guided by diagnostic criteria for the individual patient, in particular the age of IBD onset and the patient's history, and potential implications for future therapies. We outline the diagnostic care pathway for paediatric and adult patients. This guideline considers how to handle clinically actionable findings in research studies and the impact of consumer-based genomics for monogenic IBD. This document was developed by multiple stakeholders, including UK paediatric and adult gastroenterology physicians, immunologists, transplant specialists, clinical geneticists, scientists, and research leads of UK genetic programmes, in partnership with patient representatives of several IBD and rare disease charities.

Outcomes, dosing, and predictors of vedolizumab treatment in children with inflammatory bowel disease (VEDOKIDS): a prospective, multicentre cohort study

BACKGROUND

Scarce data are available on the use of vedolizumab in children with inflammatory bowel disease (IBD). We aimed to evaluate the safety, effectiveness, and dosing of vedolizumab to induce remission of IBD.

METHODS

VEDOKIDS was a paediatric, multicentre, prospective cohort study done in 17 centres in six countries. We report the 14-week outcomes as the first analyses of the planned 3-year follow-up of the VEDOKIDS cohort. Children (aged 0-18 years) with IBD who had commenced vedolizumab were followed up at baseline and at 2, 6, and 14 weeks. Children were managed according to local prescribing practices without standardisation of dosing or criteria for escalation, but the study protocol suggested dosing of 177 mg/m² body surface area (up to 300 mg maximum). The primary outcome was steroid-free and exclusive enteral nutrition-free remission at 14 weeks, analysed according to the intention-to-treat principle. Serum samples were taken for analysis of drug concentration and faecal calprotectin at baseline, and at 2, 6, and 14 weeks. Adverse events were recorded in real time and classified as severe or non-severe and related or unrelated to vedolizumab. This study is registered with ClinicalTrials.gov, NCT02862132.

FINDINGS

Between May 19, 2016, and April 1, 2022, 142 children (76 [54%] girls and 66 [46%] boys; mean age 13·6 years [SD 3·6]) were enrolled. 65 (46%) children had Crohn's disease, 68 (48%) had ulcerative colitis, and nine (6%) had unclassified IBD (those with unclassified IBD were analysed with the ulcerative colitis group). 32 (42% [95% CI 30-54]) of 77 children with ulcerative colitis and 21 (32% [23-45]) of 65 children with Crohn's disease were in steroid-free and exclusive enteral nutrition-free remission at 14 weeks. Median drug concentrations at week 14 were higher in children with ulcerative colitis than in those with Crohn's disease (11·5 μg/mL [IQR 5·5-18·1] vs 5·9 μg/mL [3·0-12·7]; p=0·006). In children who weighed less than 30 kg, the optimal drug concentration associated with steroid-free and exclusive enteral nutrition-free clinical remission was 7 μg/mL at week 14 (area under the curve 0·69 [95% CI 0·41-0·98]), corresponding to a dose of 200 mg/m² body surface area or 10 mg/kg. 32 (23%) of 142 children reported at least one adverse event, the most common were headache (five [4%]), myalgia (four [3%]), and fever (three [2%]). None of the adverse events were classified as severe, and only two (1%) patients discontinued treatment due to adverse events.

INTERPRETATION

Vedolizumab showed good safety and effectiveness at inducing remission in children with IBD at 14 weeks, especially those with ulcerative colitis. Vedolizumab should be considered in children when other approved drug interventions for IBD are unsuccessful. In children who weigh less than 30 kg, vedolizumab should be dosed by the child's body surface area (200 mg/m²) or weight (10 mg/kg).

FUNDING

The European Crohn's and Colitis Organization, the European Society for Paediatric Gastroenterology Hepatology and Nutrition, and Takeda.

Comparing Effectiveness of a Generic Oral Nutritional Supplement With Specialized Formula in the Treatment of Active Pediatric Crohn's Disease

BACKGROUND

Exclusive enteral nutrition (EEN) is the recommended induction treatment of mild to moderate active pediatric Crohn's disease (CD). This study compared outcomes of 2 proprietary polymeric formulas. Treatment effectiveness was examined along with practical aspects of formula delivery and differences in estimated treatment costs.

METHODS

Data were retrospectively collected from patients with CD who received a generic oral nutritional supplement (Fortisip) across 2 centers (RCH, Melbourne and RHSC, Edinburgh). This was compared with a prospective cohort (RHC, Glasgow) that used a specialized formula (Modulen IBD). The data collected included patient demographics, remission rates, biochemical markers, administration method, and anthropometrics. The estimated treatment cost was performed by comparing price per kcal between each formula.

RESULTS

One hundred seventy-one patients were included (106 Fortisip, 65 Modulen IBD, 70 female; median age 13.3 yrs). No difference was demonstrated in remission rate (Fortisip n = 67 of 106 [63%] vs Modulen IBD n = 41 of 64 [64%], P = .89), nonadherence rate (Fortisip n = 7 of 106 [7%] vs Modulen IBD 3 of 64 [5%], P = .57) or method of administration (NGT Fortisip use n = 16 of 106 [12%] vs Modulen IBD 14 of 65 [22%]; P = .31). There was no difference in reduction of biochemical disease markers between the groups (C-reactive protein , P = .13; erythrocyte sedimentation rate, P = .49; fecal calprotectin, P = .94). However, there was a cost-saving of around £500/patient/course if the generic oral nutritional supplement was used.

CONCLUSIONS

The generic oral nutritional supplement and specialized formulas both had similar clinical effectiveness in induction of remission in pediatric CD. However, there is considerable cost-saving when using a generic oral nutritional supplement.

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.

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.).

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.

Children included in randomised controlled trials of biologics in inflammatory bowel diseases do not represent the real-world patient mix

BACKGROUND

Patients enrolled in randomised controlled trials (RCTs) may differ from the target population due to restricted eligibility criteria.

AIM

To compare treatment response to biologics in routine practice for children with inflammatory bowel diseases (IBD) who would and would not have been eligible for enrolment in the regulatory RCT of the same drug.

METHODS

We enrolled children with IBD who initiated adalimumab, infliximab, vedolizumab or ustekinumab. The eligibility criteria as defined in the RCT of the corresponding biologic were applied to each patient. The primary outcome was 12-month steroid-free remission (SFR) without switching biologics or undergoing surgery.

RESULTS

We screened 289 children (198 [68%] with Crohn's disease [CD], 91 [32%] with ulcerative colitis [UC]) with 326 initiations of biologics. Only 62 of 164 (38%) children with moderate-to-severe disease would have been eligible for inclusion in the original RCTs. The SFR rate was higher in the eligible children (51%) than in the ineligible children (31%; OR 2.3 [95%CI 1.2-4.5]; p = 0.01). The main exclusion criterion was prohibited previous therapies (47%). Ineligible CD patients were older, more often had a family history of IBD and had higher levels of CRP than eligible children; in UC there were no differences between the groups.

CONCLUSION

Most children with IBD who initiate biologics would not have been eligible to be included in the corresponding regulatory RCTs. The outcomes of ineligible patients were worse than for eligible patients. Results from RCTs should be interpreted with caution when applied to clinical practice.

Patterns of emergency admission for IBD patients over the last 10 years in Lothian, Scotland: a retrospective prevalent cohort analysis

OBJECTIVE

It is unclear how the compounding prevalence of inflammatory bowel disease (IBD) has translated into the causes and rates of hospitalisation, particularly in an era of increased biologic prescribing. We aimed to analyse these trends in a population-based IBD cohort over the last 10 years.

DESIGN

The Lothian IBD registry is a complete, validated, prevalent database of IBD patients in NHS Lothian, Scotland. ICD-10 coding of hospital discharge letters from all IBD patient admissions to secondary care between 1 January 2010 and 31 December 2019 was interrogated for admission cause, with linkage to local/national data sets on death and prescribed drugs.

RESULTS

Fifty-seven per cent (4673/8211) of all IBD patients were admitted to secondary care for >24 h between 1 January 2010 and 31 December 2019. In patients <40 years, IBD was the commonest reason for admission (38% of admissions), whereas infection was the most common cause in those >60 years (19% of admissions). Three per cent (243/8211) of IBD patients accounted for 50% of the total IBD bed-days over the study period. Age-standardised IBD admission rates fell from 39.4 to 25.5 admissions per 100,000 population between 2010 and 2019, an average annual percentage reduction of 3% (95% CI -4.5% to -2.1%, p < 0.0001). Non-IBD admission rates were unchanged overall (145-137 per 100,000 population) and specifically for serious (hospitalisation) and severe (ITU admission or death) infection over the same period.

CONCLUSION

Despite compounding prevalence and increased biologic use, IBD admission rates are falling. The cause of admission varies with age, with infection the predominant cause in older patients.

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.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02334-6.

Benefits of Structured Pediatric to Adult Transition in Inflammatory Bowel Disease: The TRANSIT Observational Study

OBJECTIVE

To evaluate the impact of structured transition from pediatric to adult inflammatory bowel disease (IBD) services on objective patient outcomes, including disease flares, admission rates, and healthcare resource use.

METHODS

A retrospective observational study in 11 United Kingdom gastroenterology centers. Transition patients attended ≥2 visits to the gastroenterology service with both pediatric and adult personnel jointly present; non-transition patients transferred to adult services without joint visits. Data were collected from medical records for the 12-month periods before and after the date of the first visit involving adult IBD services (index visit).

RESULTS

A total of 129 patients were included: 95 transition patients and 34 non-transition patients. In the 12 months post-index visit, transition patients had fewer disease flares (P  = 0.05), were more likely to be steroid-free (71% vs 41%, P < 0.05), and were less likely to have an emergency department visit leading to hospital admission (5% vs 18%, P < 0.05). During this period, the mean estimated overall cost of care per patient was £1644.22 in the transition group and £1827.32 in the non-transition group (P = 0.21).

CONCLUSION

Structured transition from pediatric to adult IBD care services was associated with positive and cost-neutral outcomes in patients with pediatric IBD.

Dietary triggers of gut inflammation following exclusive enteral nutrition in children with Crohn's disease: a pilot study

Background

The anti-inflammatory effect of exclusive enteral nutrition on the gut of children with Crohn’s disease is rapidly lost after food reintroduction. This study assessed disease dietary triggers following successful treatment with exclusive enteral nutrition.

Methods

Nutrient intake, dietary patterns and dietary biomarkers in faeces (gluten immunogenic peptides, undigestible starch, short chain fatty acids) were assessed in 14 children with Crohn’s disease during early food reintroduction, following exclusive enteral nutrition. Groups above (Group A) and below (Group B) the median levels of faecal calprotectin after food reintroduction were assigned for comparative analysis.

Results

Intakes of fibre, gluten-containing cereals and red and processed meat were significantly higher in Group A than Group B; (median [Q1, Q3], g/day; Fibre: 12.1 [11.2, 19.9] vs. 9.9 [7.6, 12.1], p = 0.03; Red and processed meat: 151 [66.7, 190] vs. 63.3 [21.7, 67], p = 0.02; gluten-containing cereals: 289 [207, 402] vs. 203 [61, 232], p = 0.035). A diet consisting of cereals and meat products was predictive (92% accuracy) of higher faecal calprotectin levels after food reintroduction. In faeces, butyrate levels, expressed as absolute concentration and relative abundance, were higher in Group A than Group B by 28.4 µmol/g (p = 0.015) and 6.4% (p = 0.008), respectively. Levels of gluten immunogenic peptide and starch in faeces did not differ between the two groups.

Conclusions

This pilot study identified potential dietary triggers of gut inflammation in children with Crohn’s disease after food reintroduction following treatment with exclusive enteral nutrition.

Trial registration: Clinical trials.gov registration number: NCT02341248; Clinical trials.gov URL: https://clinicaltrials.gov/ct2/show/NCT02341248 (retrospectively registered).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-02029-4.

Inflammatory Bowel Disease in Patients with Congenital Chloride Diarrhoea

BACKGROUND

Congenital chloride diarrhoea [CLD] is a rare autosomal recessive disease caused by mutations in the solute family carrier 26 member 3 [SLC26A3] gene. Patients suffer from life-long watery diarrhoea and chloride loss. Inflammatory bowel disease [IBD] has been reported in individual patients with CLD and in scl26a3-deficient mice.

METHODS

We performed an international multicentre analysis to build a CLD cohort and to identify cases with IBD. We assessed clinical and genetic characteristics of subjects and studied the cumulative incidence of CLD-associated IBD.

RESULTS

In a cohort of 72 patients with CLD caused by 17 different SLC26A3 mutations, we identified 12 patients [17%] diagnosed with IBD. Nine patients had Crohn's disease, two ulcerative colitis and one IBD-unclassified [IBD-U]. The prevalence of IBD in our cohort of CLD was higher than the highest prevalence of IBD in Europe [p < 0.0001]. The age of onset was variable [13.5 years, interquartile range: 8.5-23.5 years]. Patients with CLD and IBD had lower z-score for height than those without IBD. Four of 12 patients had required surgery [ileostomy formation n = 2, ileocaecal resection due to ileocaecal valve stenosis n = 1 and colectomy due to stage II transverse colon cancer n = 1]. At last follow-up, 5/12 were on biologics [adalimumab, infliximab or vedolizumab], 5/12 on immunosuppressants [azathioprine or mercaptopurine], one on 5-ASA and one off-treatment.

CONCLUSIONS

A substantial proportion of patients with CLD develop IBD. This suggests the potential involvement of SL26A3-mediated anion transport in IBD pathogenesis. Patients with CLD-associated IBD may require surgery for treatment failure or colon cancer.

Pathogenesis of Musculoskeletal Deficits in Children and Adults with Inflammatory Bowel Disease

Musculoskeletal deficits are among the most commonly reported extra-intestinal manifestations and complications of inflammatory bowel disease (IBD), especially in those with Crohn’s disease. The adverse effects of IBD on bone and muscle are multifactorial, including the direct effects of underlying inflammatory disease processes, nutritional deficits, and therapeutic effects. These factors also indirectly impact bone and muscle by interfering with regulatory pathways. Resultantly, individuals with IBD are at increased risk of osteoporosis and sarcopenia and associated musculoskeletal morbidity. In paediatric IBD, these factors may contribute to suboptimal bone and muscle accrual. This review evaluates the main pathogenic factors associated with musculoskeletal deficits in children and adults with IBD and summarises the current literature and understanding of the musculoskeletal phenotype in these patients.

Withdrawal of Combination Immunotherapy in Paediatric Inflammatory Bowel Disease-An International Survey of Practice

OBJECTIVES

To assess current practices around the use of combination immunosuppression in paediatric inflammatory bowel disease (PIBD) with a focus on the subsequent withdrawal process.

METHODS

A web-based, 43-question survey.

RESULTS

Surveys were completed by 70 paediatric gastroenterologists (PGs) from 27 nations across Europe, North America, Oceania and Asia from 62 centres covering approximately 15,000 PIBD patients (median of 200 patients [interquartile range (IQR) 130-300] per centre). Routine use of co-immunosuppression was significantly higher with infliximab (IFX) versus adalimumab (ADL) ([61/70, 87.1%] compared with [23/70, 32.9%]; P < 0.01). Thiopurines (azathioprine [AZA] or 6-mercaptopurine) were the preferred option overall for co-immunosuppression. They were favoured with either IFX or ADL (76% and 77%, respectively) and in both ulcerative colitis (UC) and Crohn disease (CD) (84% and 69%) compared with methotrexate (MTX).Immunomodulators were the preferred choice as the initial drug to be withdrawn from the combination therapy rather than anti-tumour necrosis factor-alpha (anti-TNFα) therapy (59/67, 88% [P < 0.01]). The most common withdrawal time was after 6-12 months, with this decision usually based on clinical assessment rather than a scheduled withdrawal time (51/67, 76% vs 16/67, 24%). Indicators of mucosal healing and therapeutic drug monitoring results tended to be the most important "clinical factors" in the withdrawal decision (P = 0.05).

CONCLUSION

Most PG's favour initial withdrawal of immunomodulator (usually thiopurines) rather than biologic therapy in the step-down process, usually after 6-12 months based on sustained clinical remission. This survey precedes an in-depth, multicentre study of clinical outcomes of withdrawal of co-immunosuppression in PIBD.

Anti-SARS-CoV-2 antibody responses are attenuated in patients with IBD treated with infliximab

OBJECTIVE

Antitumour necrosis factor (anti-TNF) drugs impair protective immunity following pneumococcal, influenza and viral hepatitis vaccination and increase the risk of serious respiratory infections. We sought to determine whether infliximab-treated patients with IBD have attenuated serological responses to SARS-CoV-2 infections.

DESIGN

Antibody responses in participants treated with infliximab were compared with a reference cohort treated with vedolizumab, a gut-selective anti-integrin α4β7 monoclonal antibody that is not associated with impaired vaccine responses or increased susceptibility to systemic infections. 6935 patients were recruited from 92 UK hospitals between 22 September and 23 December 2020.

RESULTS

Rates of symptomatic and proven SARS-CoV-2 infection were similar between groups. Seroprevalence was lower in infliximab-treated than vedolizumab-treated patients (3.4% (161/4685) vs 6.0% (134/2250), p<0.0001). Multivariable logistic regression analyses confirmed that infliximab (vs vedolizumab; OR 0.66 (95% CI 0.51 to 0.87), p=0.0027) and immunomodulator use (OR 0.70 (95% CI 0.53 to 0.92), p=0.012) were independently associated with lower seropositivity. In patients with confirmed SARS-CoV-2 infection, seroconversion was observed in fewer infliximab-treated than vedolizumab-treated patients (48% (39/81) vs 83% (30/36), p=0.00044) and the magnitude of anti-SARS-CoV-2 reactivity was lower (median 0.8 cut-off index (0.2-5.6) vs 37.0 (15.2-76.1), p<0.0001).

CONCLUSIONS

Infliximab is associated with attenuated serological responses to SARS-CoV-2 that were further blunted by immunomodulators used as concomitant therapy. Impaired serological responses to SARS-CoV-2 infection might have important implications for global public health policy and individual anti-TNF-treated patients. Serological testing and virus surveillance should be considered to detect suboptimal vaccine responses, persistent infection and viral evolution to inform public health policy.

TRIAL REGISTRATION NUMBER

ISRCTN45176516.

Paediatric Inflammatory Multisystem Syndrome Temporally Associated With SARS-CoV-2 [PIMS-TS] in a Patient Receiving Infliximab Therapy for Inflammatory Bowel Disease

Paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 [PIMS-TS] is a newly described condition. It has a spectrum of presentations proposed to occur as part of a post-infectious immune response. We report the first case of PIMS-TS in a child on established anti-tumour necrosis factor alpha [anti-TNFα] therapy; a 10 year-old girl with ulcerative colitis treated with infliximab. The patient had 6 weeks of daily fever with mucocutaneous, gastrointestinal, renal, and haematological involvement. Biomarkers of hyperinflammation were present including: hyperferritinaemia [up to 691 µ/L; normal 15-80 µg/L], C-reactive protein [CRP] [ >100mg/L for  >10 days, normal 0-5 mg/L], erythrocyte sedimentation rate [ESR] consistently  >100mm/h [normal 0-15 mm/h], raised white cell count with neutrophilia, elevated D-dimer and lactate dehydrogenase [LDH], anaemia and Mott cells on bone marrow analysis. Extensive investigations for alternative diagnoses for pyrexia of unknown origin [PUO] were negative. The condition was refractory to treatment with intravenous immunoglobulin [IVIG] but improved within 24 h of high-dose methylprednisolone. Infliximab treatment followed and the patient has remained well at follow-up. Polymerase chain reaction [PCR] and serology for SARS-CoV-2 were negative. Current series report such negative findings in up to half of cases. The patient experienced a milder clinical phenotype without cardiac involvement, shock, or organ failure. Accepting the wide spectrum of PIMS-TS presentations, it is possible that previous anti-TNFα therapy may have attenuated the disease course. Given the uncertainty around therapeutic strategies for PIMS-TS, this case supports the need for further investigation into continuing infliximab as a treatment option for the condition.

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.

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.

Clinical Genomics for the Diagnosis of Monogenic Forms of Inflammatory Bowel Disease: A Position Paper From the Paediatric IBD Porto Group of European Society of Paediatric Gastroenterology, Hepatology and Nutrition

BACKGROUND

It is important to identify patients with monogenic IBD as management may differ from classical IBD. In this position statement we formulate recommendations for the use of genomics in evaluating potential monogenic causes of IBD across age groups.

METHODS

The consensus included paediatric IBD specialists from the Paediatric IBD Porto group of the European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and specialists from several monogenic IBD research consortia. We defined key topics and performed a systematic literature review to cover indications, technologies (targeted panel, exome and genome sequencing), gene panel setup, cost-effectiveness of genetic screening, and requirements for the clinical care setting. We developed recommendations that were voted upon by all authors and Porto group members (32 voting specialists).

RESULTS

We recommend next-generation DNA-sequencing technologies to diagnose monogenic causes of IBD in routine clinical practice embedded in a setting of multidisciplinary patient care. Routine genetic screening is not recommended for all IBD patients. Genetic testing should be considered depending on age of IBD-onset (infantile IBD, very early-onset IBD, paediatric or young adult IBD), and further criteria, such as family history, relevant comorbidities, and extraintestinal manifestations. Genetic testing is also recommended in advance of hematopoietic stem cell transplantation. We developed a diagnostic algorithm that includes a gene panel of 75 monogenic IBD genes. Considerations are provided also for low resource countries.

CONCLUSIONS

Genomic technologies should be considered an integral part of patient care to investigate patients at risk for monogenic forms of IBD.

Identifying Health Economic Considerations to Include in the Research Protocol of a Randomized Controlled Trial (the REDUCE-RISK Trial): Systematic Literature Review and Assessment

Background

The REDUCE-RISK trial was set up to compare the effectiveness of weekly subcutaneously administered methotrexate with daily oral azathioprine or 6-mercaptopurine in low-risk Crohn disease (CD) or subcutaneously administered adalimumab (ADA) in high-risk CD in a pediatric population (age 6-17 years).

Objective

The aim of this study is to perform a systematic review to provide input into the research protocol to gather the necessary information to improve the performance of an evidence-based economic evaluation when the trial is finished.

Methods

The Centre for Reviews and Dissemination (CRD) Health Technology Assessment (HTA) database, websites of HTA institutes, CRD’s National Health Service Economic Evaluation Database, MEDLINE (OVID), and Embase databases were consulted to retrieve (reviews of) relevant economic evaluations. Studies were eligible if they included a pediatric or adult population with inflammatory bowel diseases (CD and ulcerative colitis [UC]) treated with ADA (Humira). There were no restrictions on the comparator. Only economic evaluations expressing outcomes in life years gained or quality-adjusted life years gained were selected.

Results

A total of 12 primary studies were identified. None of these studies included a pediatric population because of a lack of supporting trials. The economic evaluations identified in our systematic review indicate that ADA is an appropriate intervention for inclusion in such a trial. From a health economic point of view, it is important to make an incremental analysis comparing such an intervention with standard care and not immediately versus another (expensive) biological treatment. Information on the impact of children’s school attendance and parents’ productivity is currently lacking in economic evaluations, and none of the underlying trials measured quality of life (QoL) using a generic utility instrument.

Conclusions

The review of the economic literature on ADA for the treatment of patients with CD supports the performance of a trial with biologicals in pediatric patients, including making a distinction according to disease severity. Conducting an economic literature review enabled us to decide which variables should be added to the research protocol from an economic point of view. Measurements for children’s and parents’ QoL (EuroQol 5-Dimension questionnaires), children’s school attendance, and parents’ productivity (WPAI-CD-CG questionnaire) were added to the research protocol. This will provide support for the calculation of the cost-effectiveness of the interventions evaluated in the REDUCE-RISK trial.

Trial Registration

ClinicalTrials.gov NCT02852694; https://clinicaltrials.gov/ct2/show/NCT02852694

Combination Immunotherapy Use and Withdrawal in Pediatric Inflammatory Bowel Disease-A Review of the Evidence

Evidence-based guidelines have been developed outlining the concomitant use of anti-tumor necrosis factor alpha (anti-TNF) agents and immunomodulators including azathioprine (AZA) and methotrexate (MTX) in both adult and pediatric populations. However, there exists a paucity of data guiding evidence-based strategies for their withdrawal in pediatric patients in sustained remission. This narrative review focuses on the available pediatric evidence on this question in the context of what is known from the larger body of evidence available from adult studies. The objective is to provide clarity and practical guidance around who, what, when, and how to step down pediatric patients with inflammatory bowel disease (IBD) from combination immunotherapy. Outcomes following withdrawal of either of the two most commonly used anti-TNF therapies [infliximab (IFX) or adalimumab (ADA)], or immunomodulator therapies, from a combination regimen are examined. Essentially, a judicious approach must be taken to identify a significant minority of patients who would benefit from treatment rationalization. We conclude that step-down to anti-TNF (rather than immunomodulator) monotherapy after at least 6 months of sustained clinical remission is a viable option for a select group of pediatric patients. This group includes those with good indicators of mucosal healing, low or undetectable anti-TNF trough levels, lack of predictors for severe disease, and no prior escalation of anti-TNF therapy. Transmural healing and specific human leukocyte antigen (HLA) typing are some of the emerging targets and tools that may help facilitate improved outcomes in this process. We also propose a simplified evidence-based schema that may assist in this decision-making process. Further pediatric clinical studies are required to develop the evidence base for decision-making in this area.

Predicting Outcomes in Pediatric Crohn's Disease for Management Optimization: Systematic Review and Consensus Statements From the Pediatric Inflammatory Bowel Disease-Ahead Program

BACKGROUND & AIMS

A better understanding of prognostic factors within the heterogeneous spectrum of pediatric Crohn's disease (CD) should improve patient management and reduce complications. We aimed to identify evidence-based predictors of outcomes with the goal of optimizing individual patient management.

METHODS

A survey of 202 experts in pediatric CD identified and prioritized adverse outcomes to be avoided. A systematic review of the literature with meta-analysis, when possible, was performed to identify clinical studies that investigated predictors of these outcomes. Multiple national and international face-to-face meetings were held to draft consensus statements based on the published evidence.

RESULTS

Consensus was reached on 27 statements regarding prognostic factors for surgery, complications, chronically active pediatric CD, and hospitalization. Prognostic factors for surgery included CD diagnosis during adolescence, growth impairment, NOD2/CARD15 polymorphisms, disease behavior, and positive anti-Saccharomyces cerevisiae antibody status. Isolated colonic disease was associated with fewer surgeries. Older age at presentation, small bowel disease, serology (anti-Saccharomyces cerevisiae antibody, antiflagellin, and OmpC), NOD2/CARD15 polymorphisms, perianal disease, and ethnicity were risk factors for penetrating (B3) and/or stenotic disease (B2). Male sex, young age at onset, small bowel disease, more active disease, and diagnostic delay may be associated with growth impairment. Malnutrition and higher disease activity were associated with reduced bone density.

CONCLUSIONS

These evidence-based consensus statements offer insight into predictors of poor outcomes in pediatric CD and are valuable when developing treatment algorithms and planning future studies. Targeted longitudinal studies are needed to further characterize prognostic factors in pediatric CD and to evaluate the impact of treatment algorithms tailored to individual patient risk.

Predicting Outcomes in Pediatric Ulcerative Colitis for Management Optimization: Systematic Review and Consensus Statements From the Pediatric Inflammatory Bowel Disease-Ahead Program

BACKGROUND & AIMS

A better understanding of prognostic factors in ulcerative colitis (UC) could improve patient management and reduce complications. We aimed to identify evidence-based predictors for outcomes in pediatric UC, which may be used to optimize treatment algorithms.

METHODS

Potential outcomes worthy of prediction in UC were determined by surveying 202 experts in pediatric UC. A systematic review of the literature, with selected meta-analysis, was performed to identify studies that investigated predictors for these outcomes. Multiple national and international meetings were held to reach consensus on evidence-based statements.

RESULTS

Consensus was reached on 31 statements regarding predictors of colectomy, acute severe colitis (ASC), chronically active pediatric UC, cancer and mortality. At diagnosis, disease extent (6 studies, N = 627; P = .035), Pediatric Ulcerative Colitis Activity Index score (4 studies, n = 318; P < .001), hemoglobin, hematocrit, and albumin may predict colectomy. In addition, family history of UC (2 studies, n = 557; P = .0004), extraintestinal manifestations (4 studies, n = 526; P = .048), and disease extension over time may predict colectomy, whereas primary sclerosing cholangitis (PSC) may be protective. Acute severe colitis may be predicted by disease severity at onset and hypoalbuminemia. Higher Pediatric Ulcerative Colitis Activity Index score and C-reactive protein on days 3 and 5 of hospital admission predict failure of intravenous steroids. Risk factors for malignancy included concomitant diagnosis of primary sclerosing cholangitis, longstanding colitis (>10 years), male sex, and younger age at diagnosis.

CONCLUSIONS

These evidence-based consensus statements offer predictions to be considered for a personalized medicine approach in treating pediatric UC.

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.

Appraisal of the PIBD-classes Criteria: A Multicentre Validation

INTRODUCTION

The PIBD-classes criteria were developed to standardise the classification of children with inflammatory bowel disease [IBD], from Crohn's disease [CD], through IBD-unclassified [IBD-U], to typical ulcerative colitis [UC]. We aimed to further validate the criteria and to explore possible modifications.

METHODS

This was a multicentre retrospective cohort study of children diagnosed with IBD with at least 1 year of follow-up. Clinical, radiological, endoscopic, and histological data were recorded at diagnosis and latest follow-up, as well as the 23 items of the PIBD-classes criteria. The PIBD-classes criteria were assessed for redundant items, and a simplified algorithm was proposed and validated on the original derivation cohort from which the PIBD-classes algorithm was derived.

RESULTS

Of the 184 included children [age at diagnosis 13 ± 3 years, 55% males], 122 [66%] were diagnosed by the physician with CD, 17 [9%] with IBD-U, and 45 [25%] with UC. There was high agreement between physician-assigned and PIBD-classes generated diagnosis for CD [93%; eight patients moved to IBD-U] and for UC [84%; six moved to IBD-U and one to CD]. A simplified version of the algorithm with only 19 items is suggested, with comparable performance to the original algorithm [81% sensitivity and 81% specificity vs 78% and 83% for UC; and 79% and 95% vs 80% and 95% for CD, respectively].

CONCLUSIONS

The PIBD-classes algorithm is a useful tool to facilitate standardised objective classification of IBD subtypes in children. A modified version of the PIBD-classes maintains accuracy of classification with a simplified algorithm.

Alterations in Intestinal Microbiota of Children With Celiac Disease at the Time of Diagnosis and on a Gluten-free Diet

BACKGROUND AND AIMS

It is not clear whether alterations in the intestinal microbiota of children with celiac disease (CD) cause the disease or are a result of disease and/or its treatment with a gluten-free diet (GFD).

METHODS

We obtained 167 fecal samples from 141 children (20 with new-onset CD, 45 treated with a GFD, 57 healthy children, and 19 unaffected siblings of children with CD) in Glasgow, Scotland. Samples were analyzed by 16S ribosomal RNA sequencing, and diet-related metabolites were measured by gas chromatography. We obtained fecal samples from 13 children with new-onset CD after 6 and 12 months on a GFD. Relationships between microbiota with diet composition, gastrointestinal function, and biomarkers of GFD compliance were explored.

RESULTS

Microbiota α diversity did not differ among groups. Microbial dysbiosis was not observed in children with new-onset CD. In contrast, 2.8% (Bray-Curtis dissimilarity index, P = .025) and 2.5% (UniFrac distances, P = .027) of the variation in microbiota composition could be explained by the GFD. Between 3% and 5% of all taxa differed among all group comparisons. Eleven distinctive operational taxonomic units composed a microbe signature specific to CD with high diagnostic probability. Most operational taxonomic units that differed between patients on a GFD with new-onset CD vs healthy children were associated with nutrient and food group intake (from 75% to 94%) and with biomarkers of gluten ingestion. Fecal levels of butyrate and ammonia decreased during the GFD.

CONCLUSIONS

Although several alterations in the intestinal microbiota of children with established CD appear to be effects of a GFD, specific bacteria were found to be distinct biomarkers of CD. Studies are needed to determine whether these bacteria contribute to pathogenesis of CD.

Impact of COVID-19 on diagnosis and management of paediatric inflammatory bowel disease during lockdown: a UK nationwide study

BACKGROUND

COVID-19 has impacted on healthcare provision. Anecdotally, investigations for children with inflammatory bowel disease (IBD) have been restricted, resulting in diagnosis with no histological confirmation and potential secondary morbidity. In this study, we detail practice across the UK to assess impact on services and document the impact of the pandemic.

METHODS

For the month of April 2020, 20 tertiary paediatric IBD centres were invited to contribute data detailing: (1) diagnosis/management of suspected new patients with IBD; (2) facilities available; (3) ongoing management of IBD; and (4) direct impact of COVID-19 on patients with IBD.

RESULTS

All centres contributed. Two centres retained routine endoscopy, with three unable to perform even urgent IBD endoscopy. 122 patients were diagnosed with IBD, and 53.3% (n=65) were presumed diagnoses and had not undergone endoscopy with histological confirmation. The most common induction was exclusive enteral nutrition (44.6%). No patients with a presumed rather than confirmed diagnosis were started on anti-tumour necrosis factor (TNF) therapy.Most IBD follow-up appointments were able to occur using phone/webcam or face to face. No biologics/immunomodulators were stopped. All centres were able to continue IBD surgery if required, with 14 procedures occurring across seven centres.

CONCLUSIONS

Diagnostic IBD practice has been hugely impacted by COVID-19, with >50% of new diagnoses not having endoscopy. To date, therapy and review of known paediatric patients with IBD has continued. Planning and resourcing for recovery is crucial to minimise continued secondary morbidity.

The Medical Management of Paediatric Crohn's Disease: an ECCO-ESPGHAN Guideline Update

OBJECTIVE

We aimed to provide an evidence-supported update of the ECCO-ESPGHAN guideline on the medical management of paediatric Crohn's disease [CD].

METHODS

We formed 10 working groups and formulated 17 PICO-structured clinical questions [Patients, Intervention, Comparator, and Outcome]. A systematic literature search from January 1, 1991 to March 19, 2019 was conducted by a medical librarian using MEDLINE, EMBASE, and Cochrane Central databases. A shortlist of 30 provisional statements were further refined during a consensus meeting in Barcelona in October 2019 and subjected to a vote. In total 22 statements reached ≥ 80% agreement and were retained.

RESULTS

We established that it was key to identify patients at high risk of a complicated disease course at the earliest opportunity, to reduce bowel damage. Patients with perianal disease, stricturing or penetrating behaviour, or severe growth retardation should be considered for up-front anti-tumour necrosis factor [TNF] agents in combination with an immunomodulator. Therapeutic drug monitoring to guide treatment changes is recommended over empirically escalating anti-TNF dose or switching therapies. Patients with low-risk luminal CD should be induced with exclusive enteral nutrition [EEN], or with corticosteroids when EEN is not an option, and require immunomodulator-based maintenance therapy. Favourable outcomes rely on close monitoring of treatment response, with timely adjustments in therapy when treatment targets are not met. Serial faecal calprotectin measurements or small bowel imaging [ultrasound or magnetic resonance enterography] are more reliable markers of treatment response than clinical scores alone.

CONCLUSIONS

We present state-of-the-art guidance on the medical treatment and long-term management of children and adolescents with CD.

Primary care faecal calprotectin testing in children with suspected inflammatory bowel disease: a diagnostic accuracy study

OBJECTIVE

To determine the diagnostic accuracy of calprotectin to diagnose inflammatory bowel disease (IBD) in children in whom general practitioners (GPs) suspected IBD.

DESIGN

Prospective observational cohort study of a new calprotectin-based primary care referral pathway.

SETTING

48 GP practices and gastroenterology secondary care services at the Royal Devon and Exeter NHS Foundation Trust in the South-West of England, UK.

PATIENTS

195 children aged between 4 and 18 years referred on the pathway between January 2014 and August 2017 for investigation of gastrointestinal symptoms were included.

INTERVENTIONS

Primary-care-driven faecal calprotectin testing. Primary and secondary care records over 12 months from the point of calprotectin testing were used as the reference standard.

MAIN OUTCOME MEASURES

Diagnostic accuracy of calprotectin testing to detect IBD.

RESULTS

7% (13/195) tested patients were diagnosed with IBD. Using our prespecified cut-off of 100 µg/g, calprotectin had a diagnostic accuracy of 91% (95% CI 86% to 95%) with a sensitivity for distinguishing IBD from non-IBD of 100% (95% CI 75% to 100%), a specificity of 91% (95% CI 85% to 94%), a positive predictive value of 43% (95% CI 25% to 63%) and a negative predictive value of 100% (95% CI 98% to 100%). Calprotectin testing had no effect on the time to diagnosis, but a negative test contributed to saved referrals and was associated with fewer diagnostic tests in secondary care.

CONCLUSIONS

Calprotectin testing of children with suspected IBD in primary care accurately distinguishes IBD from a functional gut disorder, reduces secondary care referrals and associated diagnostic healthcare utilisation.

Dietary Strategies for Maintenance of Clinical Remission in Inflammatory Bowel Diseases: Are We There Yet?

The etiopathogenesis of Inflammatory bowel disease (IBD) is a result of a complex interaction between host immune response, the gut microbiome and environmental factors, such as diet. Although scientific advances, with the use of biological medications, have revolutionized IBD treatment, the challenge for maintaining clinical remission and delaying clinical relapse is still present. As exclusive enteral nutrition has become a well-established treatment for the induction of remission in pediatric Crohn's disease, the scientific interest regarding diet in IBD is now focused on the development of follow-on dietary strategies, which aim to suppress colonic inflammation and delay a disease flare. The objective of this review is to present an extensive overview of the dietary strategies, which have been used in the literature to maintain clinical remission in both Crohn's disease and Ulcerative colitis, and the evidence surrounding the association of dietary components with clinical relapse. We also aim to provide study-related recommendations to be encompassed in future research studies aiming to investigate the role of diet during remission periods in IBD.

International prospective observational study investigating the disease course and heterogeneity of paediatric-onset inflammatory bowel disease: the protocol of the PIBD-SETQuality inception cohort study

INTRODUCTION

Patients with paediatric-onset inflammatory bowel disease (PIBD) may develop a complicated disease course, including growth failure, bowel resection at young age and treatment-related adverse events, all of which can have significant and lasting effects on the patient's development and quality of life. Unfortunately, we are still not able to fully explain the heterogeneity between patients and their disease course and predict which patients will respond to certain therapies or are most at risk of developing a more complicated disease course. To investigate this, large prospective studies with long-term follow-up are needed. Currently, no such European or Asian international cohorts exist. In this international cohort, we aim to evaluate disease course and which patients are most at risk of therapy non-response or development of complicated disease based on patient and disease characteristics, immune pathology and environmental and socioeconomic factors.

METHODS AND ANALYSIS

In this international prospective observational study, which is part of the PIBD Network for Safety, Efficacy, Treatment and Quality improvement of care (PIBD-SETQuality), children diagnosed with inflammatory bowel disease <18 years are included at diagnosis. The follow-up schedule is in line with standard PIBD care and is intended to continue up to 20 years. Patient and disease characteristics, as well as results of investigations, are collected at baseline and during follow-up. In addition, environmental factors are being assessed (eg, parent's smoking behaviour, dietary factors and antibiotic use). In specific centres with the ability to perform extensive immunological analyses, blood samples and intestinal biopsies are being collected and analysed (flow cytometry, plasma proteomics, mRNA expression and immunohistochemistry) in therapy-naïve patients and during follow-up.

ETHICS AND DISSEMINATION

Medical ethical approval has been obtained prior to patient recruitment for all sites. The results will be disseminated through peer-reviewed scientific publications.

TRIAL REGISTRATION NUMBER

NCT03571373.

Protocol for a multinational risk-stratified randomised controlled trial in paediatric Crohn's disease: methotrexate versus azathioprine or adalimumab for maintaining remission in patients at low or high risk for aggressive disease course

INTRODUCTION

Immunomodulators such as thiopurines (azathioprine (AZA)/6-mercaptopurine (6MP)), methotrexate (MTX) and biologics such as adalimumab (ADA) are well established for maintenance of remission within paediatric Crohn's disease (CD). It remains unclear, however, which maintenance medication should be used first line in specific patient groups.

AIMS

To compare the efficacy of maintenance therapies in newly diagnosed CD based on stratification into high and low-risk groups for severe CD evolution; MTX versus AZA/6MP in low-risk and MTX versus ADA in high-risk patients. Primary end point: sustained remission at 12 months (weighted paediatric CD activity index ≤12.5 and C reactive protein ≤1.5 fold upper limit) without relapse or ongoing requirement for exclusive enteral nutrition (EEN)/steroids 12 weeks after treatment initiation.

METHODS AND ANALYSIS

REDUCE-RISK in CD is an international multicentre open-label prospective randomised controlled trial funded by EU within the Horizon2020 framework (grant number 668023). Eligible patients (aged 6-17 years, new-onset disease receiving steroids or EEN for induction of remission for luminal ± perianal CD are stratified into low and high-risk groups based on phenotype and response to induction therapy. Participants are randomised to one of two treatment arms within their risk group: low-risk patients to weekly subcutaneous MTX or daily oral AZA/6MP, and high-risk patients to weekly subcutaneous MTX or fortnightly ADA. Patients are followed up for 12 months at prespecified intervals. Electronic case report forms are completed prospectively. The study aims to recruit 312 participants (176 low risk; 136 high risk).

ETHICS AND DISSEMINATION

ClinicalTrials.gov Identifier: (NCT02852694), authorisation and approval from local ethics committees have been obtained prior to recruitment. Individual informed consent will be obtained prior to participation in the study. Results will be published in a peer-reviewed journal with open access.

TRIAL REGISTRATION NUMBER

NCT02852694; Pre-results.

A Decade of Varicella Screening Within a Paediatric Inflammatory Bowel Disease Population

INTRODUCTION

Increased risk of opportunistic infection-e.g., varicella zoster infection-secondary to therapies is a cause of morbidity in inflammatory bowel disease [IBD] patients. The UK vaccination schedule does not include varicella immunisation. We aimed to evaluate the varicella screening and immunisation programme in a paediatric IBD population.

METHODS

Data regarding IBD diagnosis, varicella status, and consequent immunisations/treatment interventions were collected retrospectively from the records of patients diagnosed with IBD over a 10-year period [2009-2018].

RESULTS

In all, 520 IBD patients were diagnosed; 505/520 [97%] had varicella testing; 46/505 [9%] were naïve. Of 501 patients, 391[78%] were tested before or within 7 days of diagnosis; this increased in the second 5-year period compared with the first (229/268 [85%] versus 162/233 [70%]; p <0.00001). Median diagnosis age of naïve patients was lower [8.3 years versus 12.8 years; p <0.00001]. Where vaccination was feasible, 21/31 [68%] had two and 7/31 [23%] one immunisation. Prednisolone induction led to lower rates of vaccination (5/13 [39%] versus 23/33 [70%] for other induction therapies; p =0.02). Of 28 vaccinated patients, 5 [18%] had suspected breakthrough varicella; and 6/18 [33%] unimmunised patients required post-exposure prophylaxis or treatment for varicella. Immunisation was associated with a decrease in patients requiring post-exposure prophylaxis (0/28 [0%] versus 5/18 [28%]; p =0.0006) and varicella-related hospital admission (1/28 [4%] versus 4/18 [22%]; p =0.01).

CONCLUSIONS

High rates of varicella screening and immunisation within a PIBD population are possible, resulting in a reduction in hospital admissions for varicella treatment. Varicella immunisation may be of increasing importance within the PIBD population with the emergence of novel therapeutic strategies.

Corona Virus Disease 2019 and Paediatric Inflammatory Bowel Diseases: Global Experience and Provisional Guidance (March 2020) from the Paediatric IBD Porto Group of European Society of Paediatric Gastroenterology, Hepatology, and Nutrition

INTRODUCTION

With the current coronavirus disease 2019 (COVID-19) pandemic, concerns have been raised about the risk to children with inflammatory bowel diseases (IBD). We aimed to collate global experience and provide provisional guidance for managing paediatric IBD (PIBD) in the era of COVID-19.

METHODS

An electronic reporting system of children with IBD infected with SARS-CoV-2 has been circulated among 102 PIBD centres affiliated with the Porto and Interest-group of ESPGHAN. A survey has been completed by major PIBD centres in China and South-Korea to explore management during the pandemic. A third survey collected current practice of PIBD treatment. Finally, guidance points for practice have been formulated and voted upon by 37 PIBD authors and Porto group members.

RESULTS

Eight PIBD children had COVID-19 globally, all with mild infection without needing hospitalization despite treatment with immunomodulators and/or biologics. No cases have been reported in China and South Korea but biologic treatment has been delayed in 79 children, of whom 17 (22%) had exacerbation of their IBD. Among the Porto group members, face-to-face appointments were often replaced by remote consultations but almost all did not change current IBD treatment. Ten guidance points for clinicians caring for PIBD patients in epidemic areas have been endorsed with consensus rate of 92% to 100%.

CONCLUSIONS

Preliminary data for PIBD patients during COVID-19 outbreak are reassuring. Standard IBD treatments including biologics should continue at present through the pandemic, especially in children who generally have more severe IBD course on one hand, and milder SARS-CoV-2 infection on the other.

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.