1. To present and discuss the evidence that malnutrition and its various presentations are important in IBD
2. To present and discuss the various approaches for nutritional screening and assessment in routine clinical practice in patients with IBD
3. To discuss the interaction between IBD nurses and dietitians within the setting of a multidisciplinary team
3. To provide practical recommendations for use by nursing staff in routine clinical practice

Educational Objectives:
1.To have an overview of growth and pubertal development at transition in IBD 
2.To emphasize the role of food restrictions, adequacy, and beliefs in patients with IBD
3. To have an overview of body perception and eating disorders and IBD

1. To provide an overview of some of the nutrition and dietary management options for IBD
2. To highlight the role of the IBD nurse in relation to nutrition and dietary management of IBD

• •       To understand what is orofacial granulomatosis & its association with Crohn’s Disease
• •       Provide an overview of treatment options
• •       To explain the background to the Cinnamon, Benzoate free diet (CBFD)
• •       Provide an overview of how to implement CBFD
• •       Highlight some of the challenges to doing CBFD

OFG is a rare disease affecting the mouth and oral cavity. It is associated with Crohn’s disease. A significant proportion of people have a positive response to dietary treatment via the cinnamon, benzoate (& chocolate) free diet (CBFD). This talk will give an overview of OFG, its treatment options and dietary management. It will look at the evidence base for CBFD and how the diet show be implemented.

1. To understand the frequency and impact of disease symptoms in patients in remission
2. To review the impact on the quality of life
3. To discuss causes for GI symptoms and extra intestinal symptoms in IBD patients in remission
4. To provide a rational clinical approach to such symptoms.

We evaluated if integration of novel diets for donors and patients in addition to fecal transplantation (FT) could increase FT remission in refractory ulcerative colitis (UC) or have an independent effect on remission. We developed a novel diet specifically designed for the dysbiosis of UC and to decrease factors that impair goblet cells or mucous production.

This was a blinded randomized controlled pilot trial in adults with UC, defined by a simple clinical colitis activity index (SCCAI) of ≥5 and < 11 and endoscopic Mayo score 2-3, refractory to medication. Group 1 received free diet and standard FT by colonoscopy on day 1and rectal enemas from a single donor on days 2 and 14 without dietary conditioning of the donor. Group 2: FT as above but with dietary pre-conditioning of the donor for 14 days and a diet (UC Diet- UCD) for the patients after FT. Group 3 received the UC Diet alone without FT. Patients underwent a repeat endoscopy at week 8. The primary endpoint was clinical steroid free remission, defined as SCCAI <3, at week 8.

Fifty-one of the 96 planned patients were enrolled. The mean age was 40.4 ±12.5 years, 28/51(54.9%) had failed a biologic, 15/40 (29.4%) were on steroids at enrolment.  Remission week 8 in Group 1 was 2/17(11.8%), Group 2 was 4/19 (21.1%), and 6/15 (40%) Group 3 (NS).  Endoscopic remission was present in Group 1: 2/17(12%), Group 2: 3/19(16%) and 4/15 (27%) Group 3. Mucosal healing (Mayo 0) was achieved only in Group 3 (3/15, 20%) vs. 0/36 patients receiving FT (P=0.022). Exacerbation of disease occurred in 3/17 (17.6%) Group1, 4/19 (21.1%) Group 2, and 1/15 (6.7%) Group 3 (NS). The study was stopped for futility by a safety monitoring board.

Fecal transplantation was not effective in this UC cohort. A UC Diet alone appeared to achieve higher clinical remission (40%) and mucosal healing than single donor FT with or without diet in mild to moderate UC failing medical therapy. This diet should be investigated further in a RCT specifically designed for the UCD. This study was supported by an ECCO Pioneer grant

Background

We studied the efficacy and safety of ustekinumab (UST) vs adalimumab (ADA) through 1 year in biologic-naïve patients (pts) with moderate-to-severe Crohn's disease.

Methods

SEAVUE was a multicenter, randomized, blinded, parallel-group, active-controlled study in adults with CD Activity Index (CDAI) scores ≥220/≤450. Biologic-naïve pts failing/intolerant to conventional therapy with any size ulcer on baseline (BL) ileocolonoscopy were eligible. Pts were randomized 1:1 to UST (⁓6mg/kg IV at BL then 90mg SC every 8 weeks [Ws]) or ADA (160/80mg SC at BL/W2, then 40mg SC every 2 Ws) per US-approved regimens (no dose modifications). Primary endpoint was clinical remission at W52 (CDAI <150). Major secondary endpoints were corticosteroid-free remission, clinical response (≥100-point CDAI decrease from BL), remission in pt-reported CDAI components (PRO-2 symptom remission: abdominal pain mean daily score ≤1 and stool frequency mean daily score ≤3), and endoscopic remission (SES-CD score ≤3/0 for pts with BL score=3) at W52 and clinical remission at W16.

Results

386 pts were randomized to UST or ADA. BL demographics and disease characteristics were balanced between groups and indicative of pts with early, moderate-to-severe CD (median CD duration, 2.58 years; CDAI, 289.5; SES-CD, 8.0). At W52, 65% of UST-treated and 61% of ADA-treated pts achieved clinical remission (Δ=4.0%; 95% CI, -5.5%, 13.5%; p=0.417). Major secondary endpoints, including endoscopic remission, were similar between groups (Table 1), as were remission rates at assessment points through W52. Some other secondary endpoints showed numerical (not statistical) differences between UST and ADA (Table 1). Key safety events are summarized in Table 2. Among UST-treated and ADA-treated pts, 34.0% and 40.5% had infections, 2.6% and 7.2% had serious adverse events (AEs) of worsening CD, and 6.3% and 11.3% had AEs that led to discontinuation (DC) of study drug, respectively. One ADA-treated pt had active pulmonary TB. Injection-site reactions associated with active treatment occurred in 1.0% of UST-treated and 10.3% of ADA-treated pts. Overall, 15.2% of UST-treated and 23.6% of ADA-treated pts DC before W52. Reasons for DC were primarily lack of efficacy (UST, 2.1% vs ADA, 5.1%), AEs (UST, 5.7% vs ADA, 10.7%), and withdrawal of consent (UST, 5.8% vs ADA, 5.1%). Time to treatment DC was longer with UST vs ADA (post hoc analysis).

Conclusion

Both UST and ADA were highly effective in this population of biologic-naïve pts. Rates of clinical remission at W52 were not statistically significantly different between treatment groups. DC rates were numerically lower for UST. Safety results were consistent with prior experience for both treatments.

Anti-TNF drugs increase the risk of serious respiratory infections and impair protective immunity following pneumococcal, influenza, and viral hepatitis vaccinations. Therefore, we sought to determine whether patients with inflammatory bowel disease treated with infliximab have attenuated serological responses following SARS-CoV-2 infection.

CLARITY IBD is a multicentre, prospective observational cohort study. Antibody responses in participants treated with infliximab were compared to 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 22nd September and 23rd December 2020.  Nucleocapsid anti-SARS-CoV2 antibodies were measured using the Roche Elecsys assay. Clinical data and serum were collected every 8 weeks. Durability was defined as nonreduction in antibody level by at least 50% from baseline.

At baseline, rates of symptomatic and proven SARS-CoV-2 infection were similar between groups. Seroprevalence was lower in infliximab- 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; odds ratio [OR] 0.66 [95% CI 0.51-0.87], p=0.0027) and immunomodulator use (OR 0.70 [95% CI 0.53-0.92], p=0.012) were independently associated with lower seropositivity (Fig 1). In patients with confirmed SARS-CoV-2 infection seroconversion was observed in fewer infliximab- than vedolizumab-treated patients (48% [39/81], vs 83% [30/36], p=0.00044) and the magnitude of anti-SARS-CoV2 reactivity was lower (median 0.8 cut off index (COI) [0.2-5.6] vs 37.0 [15.2-76.1], p<0.0001). An initial increase in anti-SARS-Cov2 antibody reactivity was observed four weeks after a positive PCR test, in vedolizumab-(47.2 COI [IQR 24.1 - 113.0] vs 14.5 COI [IQR 0.4 – 30.7], p=0.0079), but not infliximab-treated patients (0.7 COI [IQR 0.2 - 7.5] vs 1.1 COI [IQR 0.4 - 4.5], p=0.70) (Fig 2). Antibody responses after an initial positive reading were also less durable in infliximab-treated patients (hazard ratio 5.15 [95%CI 2.95-9.00]; Fig 3), but durability was not influenced by immunomodulator use.

Seroprevalence, seroconversion in PCR-confirmed cases, and the magnitude and durability of anti-SARS-CoV2 antibodies were reduced in infliximab- compared with vedolizumab-treated patients. Serological testing and virus surveillance should be considered in patients treated with anti-TNF drugs to detect suboptimal vaccine responses, persistent infection, and viral evolution to inform public health policy.

Prior data have suggested that 5-aminosalicylates (5-ASA) may be associated with an increased risk of severe COVID-19 among inflammatory bowel disease (IBD) patients. We aimed to evaluate the association of 5-ASA with severe COVID-19 in a large cohort of IBD patients.

We analyzed data from the Surveillance Epidemiology of Coronavirus Under Research Exclusion for Inflammatory Bowel Disease (SECURE-IBD) registry, a large, international database of IBD patients with confirmed COVID-19. The primary outcome was severe COVID-19, defined as intensive care unit admission, ventilator use, and/or death. Hospitalization due to COVID-19 was a secondary outcome. We performed multivariable regression modeling with a generalized estimating equation accounting for country as a random effect to analyze the association of 5-ASA with severe COVID-19. Models a priori included age, sex, race, disease phenotype (CD or UC/IBD-U), corticosteroid use, azathioprine/6-mercaptopurine use, TNF antagonist use, disease activity by physician global assessment, number of comorbidities, and days from SECURE-IBD inception to reporting. We constructed three models examining 5-ASA use as binary covariate using 1) all patients, 2) only patients on any biologic, and 3) only patients on TNF antagonists.

5,174patients were included with 212 (4.1%) severe COVID-19 events. At the time of COVID-19 infection, 1,504 patients were taking 5-ASA. 5-ASA patients were older (mean age 44 vs. 38.3 years, p<0.001), more likely to have UC (70.7% vs. 27.7%, p<0.001), less likely to be in remission (49.6% vs. 57.2%, p<0.001), and more likely to have at least one comorbidity (33.6% vs. 26.7%, p<0.001) compared to patients not on 5-ASA. 3,325 patients were on any biologic and 2,216 were on a TNF antagonist. Among all patients, 5-ASA was not associated with severe COVID-19 (adjusted OR [aOR] 1.14, 95% confidence interval [CI] 0.86-1.52) (Table 1). Prior associations of age, comorbidities, TNF antagonists, and corticosteroids with severe COVID-19 were similar to prior analyses (Table 1). In analyses restricting to those on any biologic or only TNF antagonists, there was also no significant association between 5-ASA and severe COVID-19 (aOR 0.76, 95% CI 0.38-1.50 and aOR 0.99, 95% CI 0.43-2.32, respectively). Use of 5-ASA was not associated with risk of COVID-19 related hospitalization in any analysis.

In an analysis of updated data from the SECURE-IBD registry, 5-ASA use was not associated with worse outcomes among IBD patients with COVID-19.

Evaluation of endoscopic disease severity is a key component in the management of ulcerative colitis (UC) patients.  However, endoscopic assessment suffers from substantial intra- and interobserver variation, up to 75 %, thereby limiting the reliability of individual assessments. Our aim was to develop an artificial intelligence (AI) model capable of distinguishing active from healed mucosa as well as to differentiate different levels of endoscopic disease activity.

1484 unique endoscopic images from 467 patients were extracted for classification. Two experts classified all images independent of each other according to the Mayo endoscopic subscore (MES). In case of disagreement, a third expert classified the images.

Different convolutional neural network architectures were implied in the development of the AI model. Five-fold cross-validation was employed to select the best model. Unseen test data were used for evaluation.

The final model was evaluated on its performance for distinguishing MES 0 from 1–3, MES 0–1 (i.e. mucosal healing) from 2–3, and distinguish between all MES.

The accuracy, sensitivity, specificity, positive and negative predictive value, and Cohen’s Kappa were used to evaluate the final models.

Our final model achieved at the most difficult task (distinguishing between all 4 categories of MES) a mean accuracy of 0.82, mean AUC of 0.99, test accuracy of 0.84, a sensitivity of 0.88, and a specificity of 0.81 and a weighted Cohens Kappa of 0.83 (p<0.001 compared to the experts).

The results from the other tasks are shown in table 1.

We propose a new standardised way of evaluating endoscopic images from UC patients for both clinical and academic purposes. The proposed AI model demonstrated a very good capability of distinguishing between all 4 MES levels of activity. This will optimize and unify the evaluation of the disease severity measured by the Mayo endoscopic subscore across all centres and hospitals no matter the level of medical expertise.

Treating beyond endoscopic remission, aiming for histological remission, has shown to reduce relapse and hospitalization rates in patients with ulcerative colitis (UC). However, very little is known on how histological remission associates with patient reported outcomes (PROMs).

PROMs (Simple clinical colitis activity index [SCCAI], IBD disk and Visual Analogue Scales [VAS]) were prospectively collected through a digital questionnaire in all patients with UC undergoing colonoscopy between July 21^st 2020-Jan 21^st 2021. Mayo endoscopic sub score and UCEIS were determined, as well as the Nancy histologic index (NHI) of the most affected area. Endoscopic remission was defined as Mayo endoscopic sub score 0 and UCEIS 0; histologic remission as NHI 0, absence of active inflammation as NHI ≤ 1. PRO2 remission was defined as stool frequency ≤ 1 (absolute stool frequency ≤ 3 OR 1-2 stools more than usual) and rectal bleeding score of 0.

Fifty-six paired assessments were collected in 48 unique patients (Table 1), with a histologic, endoscopic and PRO-2 remission rate of 23.2%, 28.6% and 38.2% respectively. Patients with histologic remission or absence of histologic inflammation had a significantly lower overall IBD disability (p=0.007, p=0.003) and disease activity score (p=0.003, p<0.001), as compared to patients without. In line, NHI correlated with the overall IBD disk (r=0.40, p=0.002) and SCCAI score (r=0.50, p<0.001). Many individual components of both scores (abdominal pain, arthralgia, impact on education and work/interpersonal interactions/sexual function, regulation of defecation, blood loss, general wellbeing, joint pain, numbers of stools during night/day, urgency) differed significantly between patients with and without histologic remission. VAS scores assessing general wellbeing (r=0.33, p=0.01), impact on daily activities (r=0.41, p=0.002), UC-related symptoms (r=0.42, p=0.001) and worries (r=0.40, p=0.002) correlated with histology.  Quartile analysis of the overall IBD disk and SCCAI scores confirmed the highest likelihood for histologic remission in patients with the lowest scores (Q1-Q2 vs Q3-Q4 39.3% vs 7.1%, p=0.01; 40.0% vs 9.7%, p=0.01) (Figure 1). Nevertheless, the overall accuracy of the IBD disk (0.75) or SCCAI score (0.76) for histologic remission is lower (p<0.05) than the accuracy of the Mayo endoscopic (0.90) or UCEIS (0.90) score.

Table 1 : Baseline features

In patients with UC, PROMs for disability and clinical disease activity reflect histologic disease activity and should therefore be further explored in (trial) endpoint discussions. However, they cannot fully replace endoscopic and histologic findings, and should be considered complementary.

Biologics are being used increasingly in the treatment of Inflammatory Bowel Disease. However, up to 40% of patients do not respond to biologics. Therefore, methods to predict response are imperative. We aimed to identify novel genes and pathways predictive of anti-TNF response in patients with Ulcerative Colitis (UC) undergoing electronic chromoendoscopy and probe confocal laser endomicroscopy (pCLE). We further evaluated the ex-vivo binding of fluorescent labelled biologics as markers of response

26 UC patients starting anti-TNF therapy as standard of care were recruited. Pre-treatment colonoscopy, with electronic chromoendoscopy and pCLE (Cellvizio, Mauna Kea) by injecting intravenous fluorescein (2.5-5mls), was performed to assess disease activity. Targeted biopsies were taken for fluorescein isothiocyanate (FITC)-labelled infliximab staining and RNA extraction and gene expression analysis. Ex vivo labelling was evaluated by an automated analysis: after a first pre-processing step to remove biases, the labelled regions were identified using statistical multi-level thresholding, and evaluated as area and intensity. To assess response, the same endoscopic procedure was repeated at week 12-14 after anti-TNF. cDNA libraries were prepared using QIAseq UPX 3’Transcriptome reagents and sequenced. Normalised gene expressions were obtained through the CLC Genomics Workbench. Differentially expressed genes (DEGs) (FDR-corrected P-value<0.05) were determined using the Limma package and PLS-DA modelling performed to calculate their importance (VIP score). Functionally related genes were identified and classified using DAVID tools. Strongest indicators of response were predicted by Random Forest area under the curve (AUC) analysis in this cohort and a similar validation cohort

At baseline increased binding of the labelled biologic was associated with a higher likelihood of response to treatment  (AUROC81%, accuracy77%, PPV100%, NPV63%). 342 DEGs (75 up-regulated, 267 down-regulated) distinguished responders from non-responders, 76 fell within enriched pathways. Pathways related to inflammation, chemotaxis, TGF-beta signalling, extracellular matrix and carbohydrate metabolism were reduced and cell-cell adhesion increased in responders pre-treatment. Among the 37 genes with VIP>1, CRIP2, CXCL6,EMILIN1,GADD45B, LAMA4 and MAPKAPK2 were upregulated in non-responders pre-treatment and were good predictors of response (AUROC>0.7) in this cohort and validation cohort

A higher mucosal binding of the biologics before treatment was observed in anti-TNF responders. Responsive UC patients have a less inflamed and fibrotic state pre-treatment. Chemotactic pathways, involving CXCL6 may be novel targets to treat non-responders

Interventions targeting key inflammatory mechanisms have expanded the therapeutic repertoire for ulcerative colitis (UC). However, exact molecular mechanisms associated with clinical response remain elusive. We conducted a multiplex-immunohistochemistry (IHC) study to monitor immune cell composition in biopsies from UC patients under 2 approved therapies targeting TNF (infliximab) and integrin (vedolizumab), and a phase IIa clinical trial with the selective IL-6 transsignalling inhibitor olamkicept, to identify spatiotemporal changes of mucosal immune cell compartments in relation to each mechanism of action.

Sigmoid biopsies from UC patients exposed to infliximab, vedolizumab or olamkicept (26 patients in total) at baseline and week 2, 6 and 14 after therapy induction were subjected to multiplex IHC for CD3, CD15, CD20, CD68, pSTAT3, and pan-cytokeratin (OPAL/Vectra Polaris, Akoya). Quantitative and spatial immune cell patterns captured by advanced image analysis (inForm, Akoya; R package PhenoptrReports) were analysed for differences between baseline and subsequent time points using Dunnett’s multiple comparisons test   (GraphPad Prism 8.4.3). Accepted significance levels: *p<0.05,**p<0.01, ***p<0.001.

Targeted therapies resulted in overall decrease of immune cell infiltrates (range 1.15-1.22 fold; p=0.017-0.007), irrespective of drug or specified endpoint (remission at week 14) (Fig. 1). Significant drug-specific changes of spatial immune cell distributions were discernible (Fig. 2). Anti-TNF treatment was mainly associated with decrease in CD3⁺ T cells (p=0.005) localized in the submucosa close to epithelium or in tertiary lymphoid organs. In contrast, integrin targeting resulted in fewer CD15⁺ neutrophils, mainly in the submucosal compartment (p=0.046). Olamkicept treatment resulted in unique depletion of pSTAT3⁺ cells in patients achieving remission at week 14 (not observed in remission after infliximab or vedolizumab). To decipher drug-independent features of clinical remission we assessed distance metrics between immune and intestinal epithelial cells in remission and non-remission patients and observed increase (endpoint compared to baseline) of the average distance to the nearest CD20 or CD15 cell in the remission (p=0.0054, p=0.0004) but not in the non-remission group (n.s.).

Our study strongly suggests that multiplexed spatiotemporally resolved immune cell phenotyping may provide novel insights into the dynamic shifts of immune cell compartments in UC patients undergoing targeted therapy. We propose that such highly resolved digital maps of immune cells could lead to novel tools for therapeutic stratification of IBD patients.

In Crohn’s disease (CD), biologics can induce mucosal healing and stable remission. After reaching this target, treatment de-escalation could be considered but the risk of relapse needs to be estimated. Current biomarkers used to predict relapse (C-reactive protein: CRP, faecal calprotectin) offer a limited prognostic capacity. Furthermore, they only monitor inflammation while we recently highlighted various and distinct pathological processes associated with the risk of short-term (<6 months) and mid/long-term (>6 months) relapse in CD patients stopping infliximab. Herein, the aim of our study was to further characterise this distinction.

Serum abundance of 92 proteins were measured by proximity extension assay (immune response panel, Olink)at baseline of the STORI cohort (infliximab diScon-Tinuation in CrOhn’s disease patients in stable Remission on combined therapy with Immunosuppressors, n=102). Association of markers with the risk of relapse was determined by univariable Cox model in stratified (relapse <6 months or >6 months) and non-stratified datasets. Study of protein characteristics and enrichment analyses were performed to find biological patterns differentiating short-term from mid/long-term relapsers. To evaluate the predictive capacity of markers, we combined them systematically by pairs (‘AND’ or ‘OR’ logical operators) and used log-rank statistics with false discovery rate (FDR) correction (Benjamini-Hochberg).

The risk of mid/long-term relapse was associated with a decreased circulating level of anti-inflammatory effectors while the risk of short-term relapse was associated with an increased circulating level of pro-inflammatory effectors (Fig. 1A, 1B).

The risk associated with the downstream signalling of cytokine and pattern recognition receptors showed an opposite pattern in the short-term versus mid/long-term relapsers (Fig. 1D, 1E).

The risk of short-term relapse was characterised by a perturbed circulating level of proteins inducing tolerance and immunity in antigen presenting cells (Fig. 2A, 2B).

The risk of mid/long-term relapse was characterised by an increased circulating level of proteins promoting lymphocyte tolerance (Fig. 2D, 2E) and a decreased circulating level of cellular junction proteins (Fig. 3).

In CD patients stopping infliximab, blood proteins linked to immunoregulation or cellular junctions support the distinct profiles of short-term and mid/long-term relapsers. These proteins showed a capacity to predict the relapse.

Innate Lymphoid Cells (ILC) develop from Common Lymphoid Precursors in the bone marrow, and ILC precursors (ILCP) migrate to mucosa where they mature, promote homeostasis, and provide a potent, antigen-non-specific sources of cytokines. Deciphering what local stimuli drive the final stages of ILCP maturation in these tissues remains a pressing question, as ILC frequencies can become dysregulated during chronic infection and inflammatory diseases. For example, Type-1 innate lymphoid cells (ILC1) are enriched in the mucosa of patients with active inflammatory bowel disease (IBD) and the impact of this accumulation remains elusive.

Here, we develop and use co-cultures of both murine and human iPSC-derived gut and lung organoids with ILCP and with mature ILC isolated from IBD patients’ intestinal biopsies.

Harnessing these versatile models, we demonstrate that epithelial cells provide a complex niche capable of supporting the final maturation of all helper-like ILC1, ILC2, and ILC3. Notably, organoid identity was sufficient to robustly recapitulate tissue-specific ILC imprints and frequencies, even in the absence of microbial stimuli, other cell types, or cytokine supplementation.

In addition, we show that that ILC1 drive expansion of the epithelial stem cell crypt through p38γ phosphorylation, driving a potentially pathological proliferative feedback loop between β-catenin and Cd44v6. We harnessed this model to elucidate that this phenotype was unexpectedly regulated by ILC1-derived TGFβ1. We further show that human gut ILC1 also secrete TGFβ1, and drive CD44v6 expression in both HIO epithelium and mesenchyme. As TGFβ1 is a master regulator of fibrosis, the leading indicator for surgery in IBD, we next characterised the ability of ILC1 to regulate matrix remodelling using a functionalized, synthetic hydrogel system. We show that ILC1 drive both matrix stiffening and degradation, which we posit occurs through a balance of MMP9 degradation and TGFβ1-induced fibronectin deposition.

Taken together, our work provides unprecedented insight into in situ ILC maturation, which we show to be driven by epithelial signals, and into ILC function. We also report that intestinal ILC1 modulate epithelial and matrix remodelling, which may drive either wound healing in homeostasis, but may tip toward pathology when enriched in IBD.
Moreover, our work introduces a modular organoid platform, which provides exquisite control over both environmental stimuli and host genetics, making it a powerful tool for dissecting the interactions between complex mucosal tissues and rare cell subtypes in development and disease.

Extracellular RNAs (exRNAs) are RNA species present outside of the cells in which they were transcribed. They are found in human serum, though the exact role of circulating exRNAs remains to be established, especially in inflammatory bowel diseases (IBD). Besides their potential help in our pathophysiological understanding of disease, they might serve as liquid biopsies or non-invasive biomarkers.  We characterised exRNAs in serum from IBD patients, and questioned their potential in separating ulcerative colitis (UC) from Crohn’s disease (CD).

We carried out SILVER-seq (Small Input Liquid Volume Extracellular RNA-sequencing) on serum droplets (5-7ml) from a cross-sectional cohort of 26 IBD patients (15 UC, 11 CD) with active endoscopic disease (Mayo endoscopic sub score  or Simple Endoscopic Score for Crohn’s disease ) (Table 1). Normalization and differential expression were done using DESeq2 R package, co-expression network analyses performed using WGCNA (FDR adjusted p ≤0.05). Using randomized generalized linear modelling (RGLM), a diagnostic exRNA marker was designed to separate UC from CD samples (15 UC, 11 CD). 

We detected 60,675 exRNAs in serum from IBD patients, capturing 76.1% of all genes expressed in intestinal tissue, and including highly abundant intestinal genes (e.g MUC2) and intestinal barrier genes (e.g claudin 8, occludin and RETNLB). Co-expression network analysis identified 69 clusters of which 1 significantly correlated with the distinction between CD and UC (FDR p=0.003, r=-0.70). One of the hub genes within this module (consisting of 148 genes, upregulated in UC) was GNA12 (p=2.3E-4, r=0.66 for correlation with the module eigengene), encoding for a membrane bound GTPase that plays a key role in tight junction assembly and has previously been identified as UC-specific SNP in GWAS (Figure 1). Serum GNA12 expression was not associated with faecal calprotectin (p=0.55, r=0.12), disease duration (p=0.24, r=0.25), age (p=0.43, r=0.16) or gender (p=1.0), but did correlate with other UC-specific genes including TNFRSF14 (p=0.04, r=0.4), HNF4A (p=0.04, r=-0.4) and CAMK2A (p=0.004, r=0.54). Through machine learning within the UC-specific module (containing 148 genes), we identified an 8-gene exRNA panel, including GNA12, that could accurately discriminate between UC and CD patients (accuracy 96.2%).

Figure 1: Visualisation of the identified exRNA network including GNA12

Liquid biopsies are a novel non-invasive tool in IBD biomarker development. Although larger in-depth studies are required to further validate, explore and characterise the potential of serum exRNAs in the field of IBD, the current pilot project identified a new non-invasive tool to accurately distinguish CD from UC patients.

To address the question if pediatric CD patients responding to nutritional induction therapy can be maintained in remission on dietary therapy without the use of immunosuppressive drugs, we designed a prospective randomized trial (CD-HOPE) comparing cyclic exclusive enteral nutrition (EEN) to daily supplement over a 12 month period.

CD patients (6-17 years) who successfully completed at least 6 weeks of EEN with clinical remission (wPCDAI ≤12.5) were recruited in 21 sites of the French GETAID pédiatrique between 12.2014 and 09.2018. All drug therapy had to be stopped at least 4 weeks prior to inclusion. A total of 112 patients were screened with 100 patients randomized to group A cyclic EEN (100% of caloric requirement) every 8 weeks for 2 weeks or group B daily supplementary nutrition (25% of caloric requirement). Patient stratification according to age (< 10 years or older) and previous drug exposure or not. EEN and the nutritional supplement were in form of MODULEN IBD®. Except for the two weeks of EEN in group A food access was not restricted. Primary objective was the comparison of relapse rates at 12 months (defined as a wPCDAI >12.5 at two consecutive visits) between the two groups (log-rank test per protocol). Additional analyses were performed using a multivariate regression analysis and cox model.

49 CD patients were randomized to group A (cyclic EEN) and 51 to group B (daily supplement) with 43/49 and 44/51 newly diagnosed patients without any previous drug exposure. Baseline characteristics were comparable between the two groups. Median age was 12 and 13 years, group A and B respectively. At the final 12 months visits a total of 25/49 patients (group A) remained in remission without disease activation compared to 12/51 patients (group B) (p=0.004) with a hazard ratio of 0.48 (0.29-0.80) (p= 0.0051). Kaplan Maier survival remission rates are shown in figure 1. Mean fecal calprotectine levels showed no significant difference between the two groups (297, 399 and 469 at month 0, 3, and 12 visits in group A and 480, 606, and 283 at month 0,3, and 12 visits in group B). Mucosal healing at M12 months was achieved in 25/49 patients (group A) and 18/51 patients (group B), with a mucosal healing rate of 52%  (group A) and 33% (group B). Both treatment arms showed a significant catch-up growth.

This is first trial indicating that children/adolescents with CD responding to EEN as induction therapy can be maintained on remission with a nutritional therapy without immunosuppressors/biologics. However, daily nutritional supplement with normal access to food was not successful with a relapse rate of 76%.
This study was supported by an unrestricted grant from Nestlé Health Science and sponsored by APHP.

Isolated colonic (L2) Crohn’s disease (CD) in adults is thought to have unique clinical and genetic features compared with ileal (L1) CD and ulcerative colitis (UC). Similar studies in paediatrics are scarce. Our goal was to characterize the clinical features of paediatric patients with isolated colonic CD and compare them to patients with ileo-cecal CD and those with UC.

This was a multi-center retrospective study including 21 sites affiliated with the Porto IBD group and IBD interest group of ESPGHAN. Data of paediatric patients diagnosed between 2014-2017 with L1 or L2 CD, or with UC, was collected, including information on demographic, clinical and laboratory parameters at diagnosis, end of induction, 1 year and 3 years after diagnosis (or at last follow-up).

Data was collected on 300 children (102 L1, 94 L2, 104 UC) with similar demographic features. At diagnosis, bloody stools were identified in 45% of L2 patients, compared with 15% and 95% of L1 and UC patients, respectively (P<0.001), while fever was documented in 27% of L2 patients, compared to 13% and 3% of L1 and UC patients, respectively (P<0.001). At the time of diagnosis, the median pediatric Crohn’s disease activity index for patients with L1 and L2 was 25 (IQR 17.5-37) and 27.5 (20-40), respectively, while the median pediatric ulcerative colitis activity index was 40 (30-55) for patients with UC. C-reactive protein levels were significantly higher among CD patients (both L1 and L2), compared to patients with UC, and calprotectin values were comparable. ASCA was positive in 55%, 25% and 2% (P<0.001) and pANCA in 2%, 17% and 53% (P<0.001) in L1, L2 and UC patients, respectively. Granulomas were identified in 36% of L2 patients, similar to patients with L1 (33%). For induction therapy, exclusive enteral nutrition, oral steroids and mesalazine were used in 50%, 45% and 38% of patients with L2 CD, compared with 72%, 28% and 9%, and 0%, 52% and 75% of L1 and UC patients, respectively (P<0.001). Steroid-free clinical remission at the end of induction was overall similar between groups, around 55%. At 1-year post-diagnosis, 62%, 68% and 40% were on an immunomodulator (P=0.03) and 41%, 26% and 22% were receiving anti-TNFα agent (P=0.01), of patients with L1, L2 and UC, respectively. While time to initiation of an anti-TNFα agent was significantly shorter in L1 patients compared with L2 and UC (P=0.03), time to admission and time to surgery were similar.

Paediatric patients with isolated colonic CD exhibit several clinical features which differentiate them from ileo-cecal CD and UC. Prospective studies are required to understand the pathogenesis of this unique entity and define short- and long-term outcomes.

Patients with Crohn’s disease (CD) can develop complications including stricturing and penetrating disease [1, 2]. Although reliable baseline predictors of disease progression are urgently needed to inform management strategies, few studies have comprehensively explored the phenotypic and genetic determinants of disease progression in a sufficiently powered cohort.

We used data from 13,926 patients with CD in the UK IBD BioResource to investigate the effects of clinical phenotypes and genetics on CD progression. Median follow-up was 10.6 years and total follow-up was 193,033 patient-years. We applied the Montreal classification system to define disease as B1 (inflammatory), B2 (stricturing) and B3 (penetrating). Patients with B2 or B3 disease (N = 5,185) were compared to patients with B1 disease (N = 8,471) in a multivariate model fitted with both phenotype data and a polygenic score that we developed. Associations with q-values (false discovery rate adjusted p-values) less than 0.05 were defined as statistically significant.

CD progression occurred over time from diagnosis (Figure 1). Consistent with previous findings, we confirmed factors including smoking, disease location and perianal disease were associated with disease progression [3] (Table 1). The impact of a genetic influence on disease progression was confirmed and shown to be independent of genetic effects on disease location [4]. Early prescription of medications showed a protective effect on disease progression: Infliximab, adalimumab and thiopurines significantly reduced the chance of B2/B3 progression when prescribed within two years of diagnosis. Additionally, we observed a decreased progression to B2/B3 disease in patients diagnosed recently (between 2012-2020) compared to those diagnosed before 2012. This finding persisted after conditioning on exposure to biologics and correcting for follow-up time and interval to first thiopurine prescription, and thus may be indicative of other improvements in standards of care in recent years.

Using a large, well-characterised cohort we confirm the importance of disease location, smoking status and genetics on disease progression. We highlight the positive impact of early medication prescription on disease progression and discover an independent signal relating to potential improvements in the standard of care in CD over time. These results create the framework for reliable predictors of CD progression that may better guide future CD management strategies.

Reference:
1. Cosnes, J., et al., Inflamm Bowel Dis, 2002. 8(4): 244-50
2. Lo, B., et al.,J Crohns Colitis, 2018. 12(3): 265-272
3. Torres, J., et al., J Crohns Colitis, 2016. 10(12): 1385-1394
4. Cleynen, I., et al., Lancet, 2016. 387(10014): 156-67

Current guidelines on Crohn’s perianal fistulas recommend anti-TNF treatment and suggest to consider surgical closure in amendable patients. However, long-term outcome of both treatments have not been directly compared. The aim of this study was to assess MRI healing in a patient preference RCT comparing both treatment modalities.

This multicentre, international trial compared surgical closure following anti-TNF induction (4 months) to anti-TNF therapy without surgery. Patients were counselled for both treatment arms and randomised if there was no preference. Due to the combination of a preference and randomised cohort, the appropriate sample size to detect a clinically relevant increase of 25% closure (from 15% to 40%) was flexible and adjusted for a possible skewed distribution (86 patients in case of 1:1 treatment allocation).

All Crohn’s patients ≥ 18 years with a (re)active high perianal fistula and a single internal opening were eligible. Exclusion criteria were previous failure of anti-TNF, recto-vaginal fistula, proctitis, or stoma. Patients received seton placement prior to treatment. Primary outcome was MRI healing after 18 months (defined as a complete fibrotic fistula or MAGNIFI-CD score of 0-5). Secondary outcomes included clinical healing, re-interventions and fistula recurrence.

Between September 2013 and December 2019, 7 hospitals in the Netherlands and Italy included 93 patients (59% females, median age 34 years) of which 32 were randomised. Thirty-seven patients were treated in the surgical closure group and 56 in the anti-TNF group, with comparable baseline characteristics.

After 18 months, MRI healing was significantly higher after surgical closure (41% vs 11%; P=0.002). Although a trend was seen in favour of surgical closure, clinical healing rates and surgical re-interventions were not significantly different between groups (65% vs 45%, P=0.07 and 19% vs 34%, P=0.1). After median 38 months follow-up, 12 patients in the anti-TNF group crossed over to surgical closure. Both long-term MRI healing and clinical closure in the per protocol analysis remained significantly higher for the surgical closure group (46% vs 11%, P=0.002 and 65% vs 29%, P=0.006). One patient (4%) with a MAGNIFI-CD score ≤5 developed a recurrent fistula after 46 months, whereas recurrences occurred in 37% of patients with MAGNIFI-CD score >5 (P=0.004).

These results demonstrate that surgical closure following anti-TNF induction treatment induces MRI healing more frequently than anti-TNF alone. This is associated with increased long-term clinical closure and reduced recurrences. These data suggest that Crohn’s perianal fistula patients amendable for surgical closure should be counselled for this therapeutic approach.