Ileum Research Articles

P0053 Microscopic colitis: analysis of microbiota changes in different segments of the colon and terminal ileum

Abstract Background Collagenous colitis (CC) and Lymphocytic colitis (LC) are forms of microscopic colitis (MC) that cause chronic watery diarrhoea, urgency, incontinence leading to significantly decreased quality of life1. The pathogenesis of MC is not fully understood; however, the leading theory suggests that MC develops as a pathological immune response to intestinal luminal antigens in genetically predisposed individuals2. Although the gut microbiota is thought to play an important part in this process, its exact role has not been fully explored to this day3. The aim of this study was to identify and characterize changes in bacterial composition of MC patients in terminal ileum and different colonic segments. Methods Biopsies from terminal ileum and six segments of the colon were collected during diagnostic colonoscopies. DNA extraction was performed using AllPrep DNA/RNA Micro Kit (Qiagen) following the manufacturer’s instructions. To determine bacterial composition, sequencing of the 16S rRNA variable region V3-V4 was conducted. Sequencing data were processed using DADA2, and taxonomic classification was carried out with the RDP classifier. Results In this study, biopsy samples from 20 active CC patients, 20 active LC patients, and 50 controls revealed distinct microbial profiles across different segments of the colon. When comparing CC patients with controls, three bacterial families showed consistent alterations throughout the entire colon, with Erysipelatoclostridiaceae and Coriobacteriaceae decreased and Pasteurellaceae increased. Additionally, 35 families had segment-specific changes, and 25 families displayed altered abundance in the terminal ileum. In contrast, LC patients exhibited a consistent increase in Erisypelotrichaceae across the entire colon, with 38 other families showing segmental changes, and 12 families displaying altered abundance in the terminal ileum. The comparison between LC and CC highlighted a significantly different bacterial profile, with LC showing lower abundance across many families, particularly in the terminal ileum. This segmental dysbiosis pattern, more pronounced in the proximal colon, may contribute to the distinctive pathophysiology in microscopic colitis subtypes. Conclusion This study showed significant differences in bacterial composition between CC, LC and controls in the terminal ileum and colon. Bacterial alterations were not consistent throughout the entire colon but varied between different colonic segments.

P0303 Evaluation of the Terminal Ileum on Computed Tomography of Patients with Non-Traumatic Acute Abdominal Pain in the Emergency Department

Abstract Background Crohn’s Disease (CD) may be overlooked in patients presenting to the emergency department with acute abdominal pain. We aimed to determine the frequency of CD and increased terminal ileum wall thickness on abdominal computed tomography (CT) in patients presenting to the emergency department with non-traumatic acute abdominal pain. Methods A cross-sectional observational study was conducted among patients who had presented to the emergency department with non-traumatic acute abdominal pain and underwent CT between September 2023 and September 2024. Before CT, patients with known diseases such as CD, vasculitis, tuberculosis, and lymphoma were excluded from the study. A colonoscopy was performed on patients with terminal ileum wall thickness on CT examination. Results A total of 1014 patients were admitted to the emergency department with non-traumatic acute abdominal pain, 10 (1%) of whom were determined to increase terminal ileum wall thickness. The median age was 41.2, and 7 (70%) patients were female. Median terminal ileum wall thickness was measured as 6.04 mm. 9 (90%) had limited terminal ileum, 6 (60%) had a length of wall thickness more than > 5cm, 7 (70%) had stenosis and 5 (50%) had pre-stenotic dilatation on CT. Colonoscopy revealed aphthous ulcers in the terminal ileum in 6 patients, longitudinal deep ulcers in 2 patients, and 2 patients with intact terminal ileum mucosa. 3 (0.3%) of the patients with terminal ileum wall thickness were diagnosed CD after colonoscopic examination. One patient had ileocolonic involvement with stricturing behavior, while the other two had isolated ileal involvement with inflammatory behavior. 2 patients were managed with medical treatment and the other patient with ileal resection. The remaining 5 patients with terminal ileal aphthous ulcers had a history of antibiotic, nonsteroidal anti-inflammatory drug use, or gastroenteritis within the last 3 months. Conclusion In this study, CD was detected in 3 (0.3%) patients who has previously undiagnosed, presented non-traumatic acute abdominal pain with terminal ileum wall thickness on CT. Terminal ileitis is a rare reason in patients presenting acute abdominal pain. However, CD should be kept in mind among differential diagnosis.

P0435 Comparative analysis between capsule endoscopy and ileocolonoscopy for activity detection in ileal Crohn’s disease. Preliminary results from the CAPITER study, a multicenter study from the Young Group of GETECCU

Abstract Background The terminal ileum stands out as the most frequently affected segment of the gastrointestinal tract in Crohn’s disease (CD). However, ileocolonoscopy (IC) may occasionally fail to fully explore this area. Assessing inflammation activity only in the terminal ileum may lead to underestimating the overall ileal involvement. Capsule endoscopy (CE) offers a complete examination of both the entire terminal ileum and the proximal ileal segment. Methods This study presents the preliminary analysis of an ongoing multicenter retrospective study conducted at 16 Spanish GETECCU centres. The primary outcome was to explore the concordance for null, mild, or moderate-severe activity detection between CE in the total ileum and IC in the terminal ileum. We also investigated the correlation between both examinations. Patient inclusion criteria permitted a maximum time interval of 3 months between the two examinations. The Lewis score of the third segment of the small intestine (Lewis-3S) was used for activity measurement in CE and the SES-CD index of the terminal ileum was used for IC. Retrospective inspection of endoscopic reports for score calculation was allowed. The study also included a comparative analysis of the specific evaluation of the terminal ileum. Correlation of endoscopic scores with clinical and biochemical markers was performed. Furthermore, we collected safety data and whether the therapeutic approach changed based on CE results in contrast to IC results. Results Ninety-two patients with ileal CD who underwent CE and IC have been collected. Seventy-four patients were included in the main analysis because of missing data in the remaining patients. Inflammation severity was null, low and moderate-severe in 17/35/22 patients for CE and in 51/20/3 for IC, respectively. Both scores showed weak to minimum concordance (κ 0.13 [95% CI, 0.01-0.26], p=0.03). The median Lewis-3S was 409 [IQR, 164-1294] and the median SES-CD was 2 [IQR, 0-4]. A weak correlation was observed between both scores, with a potential for a moderate association (⍴ 0.38 [95% CI, 0.17-0.6], p<0.0001). CE detected luminal stenosis in 16 patients, and IC only in one patient that was also detected by CE. CE was incomplete in 10 out of 92 patients (11%), with only one case of stenosis retention requiring surgical extraction. In patients who underwent CE and IC for known CD monitoring, CE guided a treatment change in 19 out of 53 patients (36%). No correlation between endoscopic scores and clinical or biochemical markers was observed. Conclusion In this preliminary analysis, despite the limited sample size, our findings indicate an underestimation of global ileal activity when measured by IC in comparison to CE examination.

P0348 Ultrasound enterography with a novel ultrasound contrast agent for Crohn’s Disease

Abstract Background Gastrointestinal ultrasound (GIUS) is a method with both high sensitivity and specificity for evaluating disease activity in patients with Crohn’s disease. However, detecting and classifying stenosis and ulcerations can be challenging with GIUS. Developing an ultrasound method for detecting and categorising these findings would be of significant benefit to these patients. GIUS using an oral ultrasound contrast agent containing microbubbles is a new method with the potential to improve the intestinal ultrasound examination in patients with Crohn’s disease. The goal of this study is to investigate if intestinal ultrasound with oral contrast containing Sonazoid microbubbles in a PEG solution is a feasible and safe method in patients with Crohn’s disease. Methods 24 patients with Crohn’s disease in the terminal ileum (TI) was examined with ileocolonoscopy and intestinal ultrasound with oral contrast in a phase 2, single centre prospective cross-sectional drug trial. The ultrasound examination was done using Logiq E10 in contrast hybrid mode after ingestion of 1ml Sonazoid mixed with 500ml of PEG. The quality of the examination was graded 0-3 based on the amount of contrast in the lumen. In grade 3 the terminal ileum filled completely with contrast, and this was considered a successful examination. The contrast grade and transit time to TI after ingestion was documented along with symptoms, side effects and disease activity using "Mobile Health Index for Crohn’s Disease" before and after the study visit (1). Results All the included patients completed the ultrasound examination. The examination had a feasibility of 96 % as 23/24 patients achieved contrast effect grade 3 in TI with a clear separation of the intestinal wall and lumen. Average time from ingestion to grade 3 contrast effect in the TI was 20.8 min. Average duration of contrast effect grade 3 in the TI was 50.4 min. 50% of the patients had self-limiting diarrhea after the examination, however using paired samples T test there was no significant difference in average disease activity measured by MHICD before and after the examination (p=0.685). 96% of the patients agreed or completely agreed to undergo the examination again. Conclusion All except one patient achieved successful grade 3 contrast effect in the terminal ileum with a clear separation of the lumen and intestinal wall. Half of the patients had self-limiting diarrhea, but there was no increase in Crohn’s disease activity after the contrast examination. According to our study, ultrasound with oral contrast consisting of 1ml Sonazoid and 500ml PEG is a feasible and safe method to examine patients with Crohn’s disease.

P0857 The Effectiveness of Ustekinumab in Treating Small Bowel Crohn’s Disease Assessed by Magnetic Resonance Enterology

Abstract Background Crohn’s disease (CD) is a chronic relapsing and remitting inflammatory disease that affects the whole gastrointestinal tract. Approximately two-third of the CD patients have ileitis (with or without colitis) at the time of diagnosis. There is increasing evidence suggests that small bowel Crohn’s disease (SBCD) is distinct from colonic CD in several aspects, such as genetic risk factors, clinical course and treatment response. This study aims to explore the effect of UST for SBCD and compared the treatment response in different segments of small intestine. Methods This is a retrospective observational cohort study conducted at the First Affiliated Hospital, Sun Yat-Sen University. Patients with CD receiving UST were consecutively recruited from May 2021 to June 2023. MRE assessment was performed at baseline and weeks 26, and the MaRIA score was calculated. Demographic features and clinical characteristics of patients at baseline and weeks 26 (±3 weeks) were recorded. The primary endpoint of this study was healing of severe inflammation detected by MRE at weeks 26. Improvement in inflammation assessed by MRE is defined as the difference in the Maria score, calculated by subtracting the Maria score at week 26 from the score at week 0. Define ΔMaria baseline (difference in ratings divided by week 0 ratings)greater than 50% as inflammation improvement and less than 50% as no inflammation improvement. The second endpoint was the proportion of patients achieving clinical remission (CDAI score 150 at weeks 26) and the proportion of patients reaching clinical response (the reduction of CDAI 100 points when compared with baseline). Results A total of 136 CD patients were included for this study. At 26 weeks, the inflammatory status in the ileum (p<0.001) and terminal ileum(p<0.001) showed significant improvement compared to the jejunum (Figure 1A). When accounting for baseline intestinal inflammatory status, the “relative baseline MRE inflammation change” still exhibited the same trend at 26 weeks (p<0.001) (Figure 1B). However, no statistically significant differences were observed between the ileum and terminal ileum, upper jejunum and lower jejunum. In terms of secondary outcomes, 33 patients were excluded because of missing values of CDAI. Of 103 patients included for analysis, clinical response and remission were achieved in 75 (72.8%) and 78 (75.7%) patients separately (Figure 1C). Conclusion We conducted this observational study and found that ileum location was more likely to achieve MRE response and remission than jejunum, even though there was no difference between ileum and terminal ileum.

P0693 The Chicago Mesenteric Fat Index: A Novel Biomarker for Assessing Inflammation in Pediatric Crohn’s Disease with Point of Care Intestinal Ultrasound

Abstract Background Pediatric Crohn’s disease (CD) is a chronic, progressive disorder that may result in lifelong disability. There is a need for tools that facilitate early detection and accurate assessment of disease. Point-of-care intestinal ultrasound (IUS) is an accurate and non-invasive tool that provides an alternative to magnetic resonance and/or computed tomographic enterography. In addition to bowel wall thickness (BWT) and hyperemia, mesenteric fat (MF) is one of the measures of CD severity visualized with IUS. Current guidance for grading MF is subjective and binary. We have previously proposed the Chicago Mesenteric Fat Index (CMFI) to standardize grading MF in adults, and demonstrated moderate to substantial inter-rater reliability (IRR). The aim of this study was to determine the IRR of MF assessment and validate the CMFI in pediatric CD. Methods IUS images of children with ileal CD were captured from November 2023 to May 2024. Those with prior surgery were excluded. CMFI differentiates severity based on the degree of wrapping: "none" (none or minimal MF wrapping), "incomplete" (incomplete circumferential MF wrapping with skipped areas along the terminal ileum), and "complete" (circumferential MF wrapping, continuous along the terminal ileum) (Figure 1). MF grading was performed by experienced pediatric intestinal sonographers, blinded to clinical data. IRR was analyzed using Cohen’s kappa statistic. We used population and clinical data and assessed the correlation of MF using chi-square for categorical data and Kruskal-Wallis for continuous variables. Results 48 IUS examinations in 36 patients were included [50% female, 69% ileocolonic disease, predominately non-stricturing, non-penetrating in 67%]. Median BWT on IUS was 3.55 mm [1.9-5.25] (Table 1). Of the 48 scans, 32 (67%) had presence of MF wrapping,16 had incomplete MF wrapping and 16 had complete MF wrapping. The IRR for the binary assessment of MF was substantial (k = 0.6936), and grading according to the CMFI also showed substantial agreement (k = 0.6038). MF was associated with other IUS parameters, including BWT (p<0.001 for both binary and graded index and binary), loss of bowel wall stratification (p = 0.001 for binary assessment and p = 0.002 for graded index) and the presence of hyperemia (p = 0.002 for binary assessment and p = 0.011 for graded index). MF was not associated with ileal strictures (p = 0.224 for graded index, p = 0.132 for binary assessment) (Table 1). Conclusion We demonstrate that IUS is a reliable tool for the assessment of MF in pediatric CD. MF assessment with the CMFI could be used as a potential objective non-invasive biomarker of CD severity in children, allowing for enhanced clinical decision-making and improved outcomes.

P0424 Utility of superb microvascular imaging for predicting terminal ileal lesion activity in Crohn’s disease

Abstract Background Superb microvascular imaging (SMI) is rarely used in intestinal ultrasonography (IUS) to evaluate Crohn’s disease (CD) activity. This study investigated SMI findings that can predict small or large ulcers in the terminal ileum and compared them with endoscopic findings of patients with CD. Methods Data were retrospectively collected from patients with CD who underwent IUS between September 2020 and April 2024 at our clinic and ileocolonoscopy to evaluate the terminal ileum within 3 months before or after IUS. Patients with a history of small bowel resection were excluded from the study. Based on the endoscopic findings, the lesions in the terminal ileum were classified as follows: no, aphthous (<5 mm), small (5–20 mm) and large (>20 mm) ulcers. IUS was performed using Aplio a550. SMI signals were evaluated using our simplified grading system based on the Limberg score: grade 0, no vascularisation; grade 1, short stretches of vascularity as spots; grade 2, longer stretches of vascularity or grade 3, longer stretches of vascularity reaching the mesentery 1). The modified Limberg score using SMI (mLS-SMI) was applied, with the substituted SMI grade, and the proportion of patients with endoscopic findings indicating small or large ulcers in each mLS-SMI and SMI grades was evaluated. The sensitivity and specificity of the respective mLS-SMI and SMI grades for predicting endoscopic findings of small or large ulcers were also assessed. Results This study included 204 patients (median age, 29.0 years; median disease duration, 5.2 years), 50 of whom were female. The endoscopic findings were as follows: no (n = 96), aphthous (n = 68), small (n = 25) and large (n = 15) ulcers. In total, 164, 14, 13, 11 and 5 patients presented with mLS-SMI grades 0, 1, 2, 3 and 4, respectively. Moreover, 157, 27, 12 and 8 patients exhibited SMI grades 0, 1, 2 and 3, respectively. Further, 10%, 29%, 69%, 64% and 80% of patients with mLS-SMI grades 0, 1, 2, 3 and 4, respectively, and 8%, 52%, 67% and 75% of those with SMI grades 0, 1, 2 and 3, respectively, presented with endoscopic findings indicating small or large ulcers. The sensitivity and specificity of mLS-SMI grades ≥1, ≥2, ≥3 and ≥4 for predicting small or large ulcers were 60% and 88%, 50% and 95%, 28% and 97% and 10% and 99%, respectively. The sensitivity and specificity of SMI grades ≥1, ≥2 and ≥3 for predicting small or large ulcers were 70% and 88%, 35% and 96%, and 15% and 99%, respectively. Conclusion The proportion of patients with endoscopic small or large ulcers increased with mLS-SMI and SMI grades. The sensitivity and specificity of SMI grade ≥1 were comparable to mLS-SMI grade ≥1, suggesting that SMI grade alone may suffice for evaluation. References 1)Nasuno M, Shimazaki H, Nojima M, Hamada T, Sugiyama K, Miyakawa M, Tanaka H. Serum leucine-rich alpha-2 glycoprotein levels for predicting active ultrasonographic findings in intestinal lesions of patients with Crohn’s disease in clinical remission. Medicine (Baltimore). 2023;102(32):e34628. doi: 10.1097/MD.0000000000034628.

P0447 Accurate, rapid and economical diagnosis of chronic enteropathy associated with SLCO2A1 gene and the analysis of its clinical pathological features

Abstract Background Chronic enteropathy associated with the SLCO2A1 gene (CEAS) is a rare intestinal disease caused by loss of protein function due to mutations in the SLCO2A1 gene. Currently, the clinical features of this disease are poorly understood, and diagnosis of lesions in the small intestine is challenging with limited methods, relying heavily on costly genetic sequencing. Therefore, this study aims to elucidate the clinical characteristics of Chinese CEAS patients and explore the diagnostic value of immunohistochemistry of biopsy tissues from duodenum, terminal ileum or colon site. Methods A retrospective analysis was conducted on 10 cases of CEAS admitted to the Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, from January 2015 to May 2024. Data including demographic information, clinical manifestations, laboratory and imaging results, pathological findings, genetic testing, and immunohistochemistry (IHC) results were analyzed. Results Of the 10 patients, 4 were male and 6 were female, the average age at onset was 25 years (IQR 17-36), and the average age at diagnosis was 41 years (IQR 39-44), with an interval of about 16 years from onset to diagnosis. Two patients had concurrent primary hypertrophic osteoarthropathy (PHO), both of whom were male. All patients had small intestine involvement, with the most common endoscopic findings being multiple strictures and superficial ulcers of the small intestine. Pathological findings indicated nonspecific chronic inflammation limited to the mucosa and submucosa. Five patients underwent surgical treatment, all involving partial small bowel resection. Genetic sequencing results indicated SLCO2A1 gene mutations in all 10 patients, with 7 patients having homozygous mutations and 3 having heterozygous mutations. Immunohistochemistry for SLCO2A1 protein on pathological specimens from the affected small intestine showed loss of SLCO2A1 expression in 9 patients and markedly reduced expression in 1 patient, with focal loss in specific vascular regions. Further immunohistochemistry of non-affected sites, including the descending duodenum and terminal ileum, also showed decreased or absent SLCO2A1 expression, consistent with findings in the affected areas. Conclusion CEAS is characterized by multiple small intestinal strictures, with a minority of patients also presenting with hypertrophic osteoarthropathy, which is more common in males. Immunosuppressants and biologics generally show poor efficacy. Historically, CEAS has been difficult to diagnose with a prolonged time to diagnosis, and genetic testing is costly and time-consuming. Immunohistochemical analysis of SLCO2A1 protein, regardless of whether the tissue is from affected or non-affected areas, can aid in early diagnosis.

P1175 Handheld ultrasound devices are an accurate alternative to cart-based ultrasound for IBD disease activity assessment

Abstract Background Intestinal ultrasound has revolutionised inflammatory bowel disease (IBD) care, as a quick, cost-effective, accurate and reliable tool for assessing IBD activity. Recently high-quality handheld ultrasound devices (HHUS) have emerged, representing a more accessible, cheaper alternative to expensive and cumbersome cart-based ultrasounds (CBUS), however their accuracy for IUS has not been studied. We aimed to assess the accuracy of HHUS compared to CBUS in a real-world IBD population. Methods We prospectively recruited patients attending outpatient IBD clinics in a tertiary centre from 18 July to 1 October 2024. Patients were first scanned by IUS trainees or clinicians certified by the Gastroenterological Network of Intestinal Ultrasound using 1-2 HHUS (Clarius™ L15 HD3 (CL) and/or GE™ Vscan Air CL (GE) using linear and convex probes as needed) and then CBUS. We collected baseline demographics, standard ultrasound parameters, disease activity classification, concordance with CBUS, and the predicted impact on clinical management. Qualitative statistical analyses and diagnostic accuracy calculations were performed. Results We performed IUS on 101 patients (49% ulcerative colitis, 52% Crohn’s disease, 46% male, median age 39 years, median BMI 23.4 kg/m2), using CL in 69 (total segments 260) and GE in 57 (total segments 220). The demographics and scan results are detailed in Table 1. Overall concordance for disease activity status (classified as "active" or "inactive") with CBUS was 93% for CL and 91% for GE, and 100% and 95% respectively for patients with a BMI >25 kg/m2. There were 5 discordant scans each for CL (7%) and GE (9%) mostly related to discrepancies in bowel wall thickness in either the sigmoid colon or terminal ileum (there was a discrepant Doppler result in 1 case), in which 4 cases for both GE and CL reported high clinician confidence with the results. It was anticipated that the discordant result would negatively impact management in 4 (5.8%) cases for CL and 3 (5.2%) cases for GE. Overall sensitivity and specificity were high in both CL (85% and 100%) and GE (76% and 100%) and remained reasonably high for all segments (see Figure 1). Conclusion Both CL and GE HHUS represent viable alternatives to CBUS, with high diagnostic accuracy for IUS in IBD patients with normal and high BMIs. Given significantly lower costs, use of HHUS could improve access to IUS in IBD care internationally. There is a small risk that rare discordant results could negatively impact management, however this risk could be mitigated by interpreting IUS findings in the context of other disease activity markers and considering a repeat IUS using CBUS where there is uncertainty regarding findings.

P1222 The macroscopic and microscopic distribution of IBD in patients with PSC: a polytomous latent class analysis on 3177 endoscopies

Abstract Background Inflammatory bowel disease (IBD) in patients with primary sclerosing cholangitis (PSC) is a distinct disease entity requiring specific management1. Data on characterisation of the phenotype of PSC-IBD are limited and subclassification is lacking. Therefore, this study aims to describe the macroscopic and microscopic distribution of IBD in patients with PSC. Methods A retrospective analysis was conducted on data from PSC-IBD patients included in the EpiPSC2 registry, comprising patients from 46 hospitals across the Netherlands. Data on inflammation at macro- and microscopic level in the ileum and 6 colonic segments were collected on every available endoscopy. Data after (hemi)colectomy were excluded. Polytomous latent class analysis was used to identify subgroups of IBD distribution2. First, latent class models (LCM) were fitted on all endoscopic and histologic data and Akaike and Bayesian information criteria were used to determine the optimal number of classes. After random sampling with replacement the LCM with the ideal number of groups was fitted on 20 samples of one endoscopy with inflammation per subject, and the pooled class probability was calculated per subgroup. Results A total of 3177 endoscopies from 522 PSC-IBD patients (median of 5 [IQR 2-9] endoscopies per patient) were included. The maximum depth of insertion was the terminal ileum in 62% and caecum in 27% of endoscopies. Macroscopic inflammation was observed in 1521 (48%) endoscopies from 428 patients. Segmental colon biopsies were obtained during 650 (20%) endoscopies in 237 subjects, and ileum biopsies in 144 (22%) endoscopies in 100 subjects. Microscopic inflammation in any segment was observed in 265 (41%) endoscopies. An LCM with four classes was the best fit to the macro- and microscopic data: no inflammation, right-sided colitis (pooled class probability 36%), left-sided colitis (30%), and pancolitis (34%). In right-sided colitis and pancolitis the probability of ileal involvement was 16% and 22%, whereas left-sided colitis most often displayed an absence of ileal involvement (probability of 4%) [fig.1]. For microscopic inflammation no pooled class probabilities could be calculated due to low sample size. In 139 (21%) endoscopies, LCM showed more extensive inflammation at microscopic assessment as compared to macroscopic assessment. Conclusion Macroscopic and microscopic inflammation in PSC-IBD may be classified into right sided colitis, left sided colitis, and pancolitis. The microscopic extent exceeds macroscopic inflammation in over 20% of endoscopies with segmental biopsies. Future research into the prognostic implication of this subclassification on PSC- and IBD-related outcomes is required.

P0960 Risankizumab induces radiological healing in treatment-refractory small bowel Crohn’s disease

Abstract Background Small bowel (SB) Crohn’s disease (CD) is a heterogenous condition, ranging from short segments of inflammation in the terminal ileum, to multifocal inflammatory, stricturing or fistulising phenotypes. Up to 80% of patients with CD have SB involvement and symptoms can be debilitating and difficult to treat. Despite the evolving therapeutic armamentarium of CD therapies, efficacy in SB CD remains unclear as SB radiological outcome measures are not routinely reported in clinical trials. Risankizumab has demonstrated efficacy in CD and effectiveness in a real-world setting. We aim to measure radiological improvement in patients with SB CD initiated on risankizumab across four London tertiary centres. Methods We conducted a retrospective study of patients with SB CD initiated on risankizumab between May 2021 and November 2024. We collected all available radiological data (CT/MR/US) across different time points. The primary outcome measure was radiological improvement by week 36 (defined as documented improvement by the reporting radiologist). We analysed data for patients with baseline imaging demonstrating SB inflammation (within 6 months prior to starting risankizumab) and at least 1 interval scan within 36 weeks of risankizumab initiation. Results 35 patients met the eligibility criteria, with 27 demonstrating radiologically active SB disease at baseline. 89% (31/35) of the full cohort and 93% (25/27) of those with active SB disease at baseline had ileocolonic disease. 22/27 (81%) had prior experience of ≥3 advanced therapies. 48% (13/27) had stricturing disease, 32% (9/27) had penetrating disease (9/27, 32%) and 86% (24/27) had prior luminal surgery. Median duration of follow-up was 196 (IQR, 107) days post-induction. 48% (13/27) had radiological improvement of previously active SB CD, within a median 110 (IQR 71) days. Only 3 patients demonstrating improvement were receiving additional treatment at the time of their interval scan (1/13 on oral corticosteroids and 2/13 on exclusive enteral nutrition). Separating responders chronologically at weeks 4, 8, 12, 20, 28, and 36, radiological improvement in those with baseline active disease was observed in 0/2 (0%), 4/5 (80%), 0/3 (0%), 5/9 (56%), 3/7 (43%), and 2/5 (40%) cases, respectively. Conclusion Risankizumab induces radiological healing in SB CD in a treatment-refractory cohort, with response rates as high as 50% by week 36. SB healing can be observed as early as 20 weeks into treatment.

P0992 Real-world experience of faecal microbiota transplant in ulcerative colitis

Abstract Background Faecal microbiota transplant (FMT) is an effective treatment strategy for recurrent Clostridioides difficile infection (rCDI)1, but its role in ulcerative colitis (UC), another disease involving gut dysbiosis, is less certain2. Methods Patients with active UC at St Thomas’ hospital, London were given FMT according to patient preference and MDT decision. Local approval was granted for the new procedure process in May 2018. 200ml FMT (80g stool in 0.9% saline with 12.5% glycerol) was deposited in the terminal ileum or caecum at colonoscopy, with loperamide and an anal plug to aid retention. 60-90ml FMT was given via enema on days 2, 4 and 28. Demographics (table 1), Simple Clinical Colitis Activity Index (SCCAI), Ulcerative Colitis Endoscopic Index of Severity (UCEIS) and faecal calprotectin were collected at baseline and over a 12-week follow-up (FU) period. Adverse events, hospital admissions, medication changes and colectomy incidence were recorded. Results 10 FMT administrations across 9 patients between 2018 and 2024 were analysed retrospectively. All patients had improvement in at least one measurable index (SCCAI, UCEIS or calprotectin, mean FU 6 weeks for each parameter). In all measured cases SCCAI either improved (5/6; 83%) or remained static in steroid free clinical remission (1/6, 17%), mean improvement = 2.83. 2/6 (33%) were in steroid free clinical remission after FMT. UCEIS improved in 3/5 (60%) and remained static in 2/5 (40%), mean improvement = 1. Endoscopic response (improvement ≥2) occurred in 1/5 (20%). None achieved endoscopic remission during 12-week FU. Faecal calprotectin improved in all measured cases (n=4) and by ≥50% in 2/4 (50%), but all were receiving steroids either at the time of FMT or during FU. Steroids were started in 1/9 (11%) and biologic switched in 4/9 (44%) <12 weeks after FMT. 2/9 (22%) had a biologic switch or dose escalation beyond 12 weeks. 2/9 (22%) required no change in treatment (figure 1). There were no adverse events, hospitalisations or colectomy during 12-week FU period. 2/9 patients went on to have colectomy, both >2 years post FMT. Conclusion There was clinical response or maintenance of clinical remission after FMT in all patients. This was discordant with a relatively modest endoscopic improvement, suggesting a potential placebo effect. Most patients required a change of treatment either during the 12-week FU or shortly after. Analysis was limited by other concurrent medication changes and incomplete data. Extension of FMT administration may have captured further response but this would need further evaluation. FMT was safe to deliver with no adverse events documented, no hospitalisations and no colectomy during 12-week FU.

DOP049 Vedolizumab is more effective at inducing histo-endoscopic healing in early Crohn’s Disease compared to late CD, with comparable healing rates regardless of disease location: data from the LOVE-CD trial

Abstract Background Achieving deep remission, encompassing clinical, endoscopic, and biological remission, is a long-term goal in Crohn's disease [CD] according to the STRIDE-2 guidelines. The role of histological remission in CD remains unclear. We evaluated the efficacy of vedolizumab [VDZ] for inducing histo-endoscopic remission in early versus late CD in the prospective, open-label LOVE-CD trial conducted in Belgium, the Netherlands and Hungary. Methods In the LOVE-CD trial, patients with moderate-to-severe disease (Crohn’s Disease Activity Index 220-450 and presence of ulcers at baseline endoscopy) received intravenous vedolizumab over a 52-week period. Early CD was defined as a diagnosis <24 months (treatment-naive or history of corticosteroid and/or immunomodulator use), and late CD as a diagnosis >24 months with prior anti-TNF exposure. Ileocolonoscopies were performed at three timepoints (baseline, week 26, week 52) during which biopsies were systematically collected in the terminal ileum and colon. Both the endoscopies and biopsies were centrally scored by experienced readers for the simple endoscopic score for Crohn's disease [SES-CD], Robarts’ histopathology index [RHI], and Geboes score [GS]. Endoscopic remission, histo-endoscopic mucosal improvement [HEMI], and histo-endoscopic mucosal remission [HEMR] were defined as SES-CD <4, GS ≤3B.1, and GS <2B.1 respectively. The association between histologic and endoscopic scores was studied with Spearman’s correlation coefficient. Intention-to-treat analysis with non-responder imputation was used to handle missing data. Results Of the 260 patients included in LOVE-CD (Table), 440 biopsies (336 colon, 114 ileum) from 179 patients at week 26, and 435 biopsies (323 colon, 112 ileum) from 177 patients at week 52 were analysed. There was a strong correlation between the endoscopic and histological assessment (colon r 0.69, ileum r 0.64, total r 0.64, p<0.001). Patients with early CD were more likely to achieve histological remission than patients with late CD at week 52 (38.4 % vs. 14.9%, p=0.00004). Endoscopic and histological healing rates at week 26 (endoscopic remission 36.9%, HEMI 30.4%, HEMR 24.2%) and week 52 (endoscopic remission 35%, HEMI 30%, HEMR 22.7%) were comparable. When looking at disease location, histological remission rates in the colon and ileum did not significantly differ (35.2% vs. 27.8%, p=0.15). Conclusion Vedolizumab was more efficient at inducing histo-endoscopic remission in early CD as compared to late CD, with most of the histo-endoscopic healing occurring during the first 26 weeks. Histo-endoscopic healing rates under vedolizumab were comparable in colonic and ileal disease. Histological scores (RHI, GS) are also applicable for the evaluation of ileal and colonic CD.

P0328 Faecal calprotectin and MRI are complementary tools for assessing treatment efficacy and predicting the risk of bowel damage progression in Crohn’s disease: results of the IZNOGOUD study

Abstract Background Faecal calprotectin (Fcal) and magnetic resonance imaging (MRI) could be used as non-invasive tools to monitor mucosal and transmural healing, respectively, in Crohn’s disease (CD). We assessed the agreement between Fcal and MRI in detecting active CD and to explore the complementarity of these tools in predicting long-term CD outcomes. Methods Using pooled data from two prospective studies, we included patients with CD who underwent both MRI and Fcal testing within 7 days. MRI was performed without bowel cleansing or enema but with 0.5–1L of PEG for bowel distension. MRI included a segmental assessment of jejunum, non-terminal ileum, terminal ileum (last 30 cm), right colon, transverse colon, left colon/sigmoid colon, and rectum. Transmural healing on MRI was defined as a C-score <0.5 in all segments. Patients were classified into four groups: transmural healing (both normal), MRI healing (Fcal >100 μg/g but normal MRI), biochemical healing (Fcal <100 μg/g but abnormal MRI), and no healing (both Fcal and MRI abnormal). The endpoints were the time to bowel damage progression and the time to relapse-related drug discontinuation. Survival analyses were performed using the log-rank test (univariate) and Cox models (multivariate). Results were expressed as hazard ratios (HR) with 95% confidence intervals. Results Among the 112 patients included, 6.2% (7/112), 11.6% (13/112), 18.8% (21/112), and 63.4% (71/112) achieved transmural healing, MRI healing, biochemical healing, and no healing, respectively. No significant differences were observed between the four groups. At baseline, 42% (47/112) of patients were symptomatic according to PRO-2. The agreement between IUS and Fcal for detecting active CD was low (69.6%, κ coefficient = 0.10±0.09). A total of 57 patients experienced progression of bowel damage during follow-up. Transmural healing, MRI healing (HR = 0.13[0.04-0.43]), or biochemical healing (HR = 0.24 [0.07-0.77]) were associated with a reduced risk of bowel damage progression compared to no healing (p <0.0001), with a non-significant trend favoring transmural healing over MRI or biochemical healing (Figure 1). Of the 94 patients who discontinued treatment due to relapse during follow-up, transmural healing was associated with a lower risk of treatment discontinuation compared to biochemical healing (HR = 0.29[0.02-0.45], p = 0.003), MRI healing (HR = 0.45[0.02-0.60], p = 0.001), or no healing (HR = 0.11[0.018-0.04], p = 0.002). Conclusion Transmural healing, as assessed by two non-invasive tools, MRI and fecal calprotectin, appears to be associated with a reduced risk of bowel damage progression in patients with Crohn’s disease, suggesting an interesting complementarity of these tools in daily clinical practice.

OP03 Mapping the observable IBDverse: Using massive-scale single-cell RNA sequencing of gut and blood samples to nominate genes, cell types and pathways driving IBD susceptibility

Abstract Background Genome-wide association studies (GWAS) have identified 370 loci associated with inflammatory bowel disease (IBD) susceptibility1. The majority of these are driven by non-coding variants, thought to dysregulate the expression of a nearby gene. The dysregulated disease effector gene, and the operative cell-type(s) is often unknown. Previous efforts to nominate effector genes have relied on identifying expression quantitative trait loci (eQTL) and expression-linked genes (eGenes). However, gene expression is often derived from healthy individuals, a single, non-primary site, and measured using bulk RNA sequencing. This likely misses cell-, site-, or disease-specific genetic effects, and has nominated disease effector genes for only a minority of IBD loci. Methods To better characterise the universe of IBD effector genes, we created IBDverse - the largest collection of single-cell RNAseq data from the terminal ileum (TI, nCD=119, nHealthy=243), rectum (nHealthy=275) and blood (nCD=95) - a total of >2.4 million high quality transcriptomes from 732 samples across 396 individuals. After grouping cells into different cell types, we mapped genetic variants associated with gene expression changes. Disease effector genes were nominated by identifying expression-linked genetic effects likely driven by the same causal variant as an IBD GWAS signal, as determined by colocalisation analysis2. Results Across all tissues, we identify 102 transcriptionally distinct cell types (Fig 1), and genetic effects associated with the expression of >17,000 genes. For 507 genes, the genetic association for their expression was strongly associated with genetic effects for IBD susceptibility, suggesting them to be drivers of disease risk. Remarkably, this doubles the previous best efforts to nominate disease effector genes3, doing so at >52% of IBD susceptibility loci. As well as their nomination, this study also helps contextualise disease effector expression variation. Disease effector genes were detectable in only a single tissue or cell annotation in >40% of cases, highlighting the need for high resolution data obtained across multiple tissues. We also find the first evidence for upregulation of RASGRP1, a gene previously correlated with exacerbated colitis in mice4, to drive Crohn’s disease susceptibility. As this is identified in a subset of tissue-resident memory T cells, and only from the TI, this also suggests this cell type and tissue as governing this effect. Conclusion This study serves as a step change in the understanding of cellular heterogeneity of these tissues, provides a compendium of genetic regulatory effects across constituent cell types, and quantifies the relevance of these to IBD susceptibility. References Liu et al., (2023). Nat. Genetics. ‘Genetic architecture of the inflammatory bowel diseases across East Asian and European ancestries’ Giambartolemi et al., (2014) PLOS Genetics. ‘Bayesian test for colocalisation between pairs of genetic association studies using summary statistics’ Panousis et al., (2024) Nat. Comms (in press). Wang et al., (2022) Nat. Comms. ‘RasGRP1 promotes the acute inflammatory response and restricts inflammation-associated cancer cell growth’

P0610 Comparison of endoscopic remission and MRI defined remission using the simplified MaRIA score at week 48 from the PROFILE trial

Abstract Background In the PROFILE trial patients newly-diagnosed with Crohn’s disease on “top-down” (infliximab + immunomodulator) treatment had significantly higher rates of ulcer-free endoscopic remission (SES-CD ulcer subscore = 0) at week 48 compared to those on “accelerated step-up” therapy (67% vs 44%, p<0.0001) [1]. Here, we explored the utility of MRI-defined remission as an alternative week 48 endpoint. Methods PROFILE enrolled 386 patients with endoscopically active new-diagnosis Crohn’s disease. MRI-enterography was performed at week 48 and centrally-read by a validated pool of 5 GI radiologists. Endoscopic and MRI defined remission was compared between “top-down” and “accelerated step-up” groups. Detection of remission and ulceration were compared pairwise between MRI and colonoscopy using McNemar’s test. MRI remission was defined by a simplified Magnetic Resonance Index of Activity (MARIAs) global score of 0 or ulcer subscore of 0; and endoscopic remission by SES-CD ulcer subscore of 0 (no ulcers - as published) and ≤1 (i.e. permitted ulcers 1-5mm). MARIAs sigmoid + descending colon scores were merged to enable comparison to SES-CD in five segments (terminal ileum, right, transverse, left colon and rectum). Data were analysed using Python 3.12.1 packages numpy, pandas, matplotlib (VS Code). Results Week 48 endoscopic data were available for 252 participants. Endoscopic remission using SES-CD ulcer subscore ≤1 at week 48 was more frequent in “top-down” compared to “accelerated step-up” (86% [115/134] vs 71% [84/118] patients, p=0.004). Week 48 MRI data were available for 208 of these participants. MRI remission at week 48 was similar between “top-down” and “accelerated step-up” groups by global MARIAs score (81% [89/109] vs 79% [79/99], p=0.720) and MARIAs ulcer subscore (95% [104/109] vs 96% [95/99], p=0.728). McNemar’s pairwise comparison demonstrated endoscopy had superior sensitivity for detecting ulcers compared to MRI at week 48 (p<0.0001). Comparing SES-CD vs MARIAs across 1035 segments in 208 patients: 43 segments had ulcers >5mm (SES-CD ulcer subscore >1) on colonoscopy of which 1/43 was detected by MRI; and 96 segments had ulcers 1-5mm (SES-CD ulcer subscore = 1), with 4/96 detected by MRI. The remaining 884 segments were normal (SES-CD ulcer subscore = 0). Conclusion MRI had low sensitivity for detecting ulceration compared to colonoscopy. The difference in week 48 outcomes in PROFILE between “top-down” and “accelerated step-up” treatment arms using endoscopic definitions of remission were not seen on MRI. As even mild endoscopic activity correlates with adverse long-term prognosis in Crohn’s [2] so MARIAs-defined trial endpoints may have low utility compared to the endoscopic gold-standard.

P0253 Identification of baseline Pediatric Crohn’s disease location and complications: How do intestinal ultrasound and magnetic resonance enterography compare?

Abstract Background Pediatric patients with newly diagnosed Crohn’s disease (CD) often undergo magnetic resonance enterography (MRE) to assess bowel not accessible by endoscopy and to evaluate for CD complications. In contrast to intestinal ultrasound (IUS), MRE access is quite limited, expensive, and not feasible for young patients. Little is known about how MRE and IUS compare, with a recent systematic review reporting inconclusive results when comparing diagnostic accuracy in pediatric CD. This study therefore aimed to compare MRE and IUS at diagnosis of pediatric CD. Methods Pediatric patients (≤18 years old) seen for suspected CD were prospectively consecutively enrolled (2019-2022) and underwent endoscopy (Simple Endoscopic Score for Crohn Disease (SES-CD)), MRE, IUS (performed by IUS trained pediatric gastroenterologists), calprotectin, blood work and assessment (weighted Pediatric Crohn Disease Activity Index (wPCDAI)). A blinded pediatric radiologist read all MREs. An interim analysis was done after 21 patients before the final analysis. Statistical analyses included descriptive statistics and Pearson chi-square. Results 58 patients (n=38, 66% male) were included; median age 13 years (IQR 10-15, range 6-17). Disease activity at diagnosis was moderate: median SES-CD 14 (IQR 10-21), wPCDAI 48 (IQR 34-59), calprotectin 1455ug/g (IQR 840-2454), C-reactive protein 47mg/L (IQR 27-72), and erythrocyte sedimentation rate 33mm/hr (IQR 18-46). Jejunum and proximal ileum involvement had high levels of agreement between MRE and IUS for non-inflamed bowel, but less agreement for inflammation (Figure 1). There was higher agreement for inflamed distal ileum compared to proximal ileum or jejunum (Figure 1). MRE and IUS performed similarly in identifying endoscopically inflamed bowel, with the highest accuracy for the terminal ileum (TI) (Figure 2). Both were more accurate for moderate/severe (segment SES-CD≥7) vs. mild/moderate/severe disease (segment SES-CD≥3) (Figure 2). For patients with endoscopic TI strictures (n=8/58, 14%), this was seen on MRE (n=8/8, 100%) more often than IUS (n=5/8, 63%). Those without endoscopic TI strictures were still reported on MRE (n=15/50, 30%), more than IUS (n=2/50, 4%). There were no significant differences in MRE vs. IUS bowel wall thickness measurements in all segments of the small and large bowel (p>0.05). Conclusion IUS and MRE performed similarly in distal small bowel and colonic CD assessment in both the identification and measurement of inflamed bowel. More proximal small bowel disease may be over reported by MRE or under reported by IUS. MRE also over reported TI stricturing disease. Both may miss mild CD. For initial and longitudinal pediatric CD assessment, repeating IUS rather than MRE is a viable option.

P1138 Curcumin-QingDai combination for patients with active Crohn’s disease: Initial real-world experience from a retrospective multi-center cohort study

Abstract Background A combination of Curcumin and QingDai (CurQD) was shown to exert aryl-hydrocarbon-receptor (AhR) pathway activation and to be effective in ulcerative colitis. However, its benefit in Crohn’s disease (CD) has not been studied Methods A retrospective cohort study of patients with active CD treated with CurQD at three academic centers. Active disease was defined by PRO-2 SF≥2 and AP ≥1. The primary endpoint was the rate of clinical remission at the end-of-induction (weeks 8-12), PRO2 SF≤1 and AP=0. Secondary endpoints included biomarker response (FCP drop ≥50% in a patient with FCP >250mcg/gr at baseline) and remission (FCP drop ≥50% and FCP<250mcg/gr at end-of-induction) and CurQD retention. Public-domain GTEx dataset was explored for mRNA expression of the target AhR in colon versus small intestinal mucosa Results Thirty patients were identified for the safety dataset, of whom 13/30 (43%) were bio-experienced, and 25 were eligible for inclusion in the efficacy analysis,. Clinical PRO2 remission at the end of induction was achieved in 12/25 (48%) of patients and clinical response in 19/25 (76%), with an overall reduction in median PRO2 score from 15 (95%CI 13-19.7) to 4 (95%CI 2-8.7, p<0.001). Biomarker remission and response were observed in 11/20 (55%) and 15/20 (75%), respectively, of patients with baseline FCP>250mcg/gr, with an overall reduction in median FCP from a baseline 639 mcg/gr (95%CI 128-5480) to 138mcg/gr (95%CI 5-1470, p=0.001). Biomarker remission was observed in 8/11 (73%) of patients with colonic-involving L2/L3 disease versus 3/9 (33%) L1 extent (OR 4.5, 95%CI 0.8- 24, p=0.08). After 8-months’ median follow-up (range 2-26 months), 16/19 (84%) of responding patients were still taking CurQD. Three patients experienced headaches and three had abdominal pain/diarrhea. Two of the six stopped CurQD due to these symptoms. One patient had elevated liver transaminases X3/normal, which resolved upon halving CurQD dose. To explore if the signal for a difference in efficacy in patients with or without colonic involvment relates to different expression of the target AhR in colon versus small bowel, an analysis of GTEx dataset was performed, which revealed comparable AhR mRNA expression levels in human colonic and terminal ileum segments. Conclusion In this first-reported real-world experience, the AhR-agonist CurQD was effective in inducing and maintaining clinical and biomarker remission in CD patients, including in biologic-experienced patients

P0147 Regulation of Inflammatory Pathways by miR-338-3p and miR-378a-3p: A Novel Approach for Crohn’s Disease Treatment

Abstract Background MicroRNAs (miRNAs), key regulators of gene expression, are promising biomarkers and therapeutic targets in inflammatory bowel disease (IBD) due to their roles in immune response and tissue integrity. This study explores miRNA roles in IBD, focusing on Crohn's disease (CD) pathogenesis and potential therapies. We analyzed epithelial cell-derived miRNA expression in CD patients versus healthy controls and investigated how these miRNAs modulate inflammation in experimental IBD models. Methods Terminal ileum samples were prospectively collected via ileocolonoscopy from non-IBD healthy controls (n=26), CD patients in remission (n=34), and active CD patients (n=42). Clinical remission was defined as a Crohn’s Disease Activity Index score below 150 with endoscopic mucosal healing. For active CD cases, samples were taken from inflamed and non-inflamed regions. miRNA levels were quantified by small-RNA sequencing and validated by qRT-PCR. Based on these results, specific miRNAs were selected, and single-stranded mimics were administered in a 2.5% DSS-induced colitis model to evaluate their effects. Histological grading, immunohistochemistry, flow cytometry, and microbiome analysis using mouse fecal samples were performed. Results Small-RNA sequencing revealed distinct miRNA expression patterns in CD patients, both in remission and in active states (including inflamed and non-inflamed tissues), compared to healthy controls. qRT-PCR validation showed significantly reduced expression of miR-141-3p, miR-338-3p, miR-378a-3p, and miR-200b-3p, along with significantly increased levels of miR-125b-5p, miR-29b-3p, and miR-155-5p in inflamed tissue of active CD patients. Receiver operating characteristic curve indicated diagnostic potential for these miRNAs in relation to disease activity and endoscopic inflammation. In a DSS-induced colitis mouse model, miR-338-3p and miR-378a-3p showed anti-inflammatory effects, reducing body weight loss, colon inflammation, and immune cell markers. Target analyses identified MACC1 and IL-33 as key mRNA targets. Immunohistochemistry indicated an IL-33 pathway-dependent anti-inflammatory response via miR-378-3p, while miR-338-3p appeared to regulate gut inflammation by targeting MACC1 gene expression. In vitro analyses revealed that IL-33 activates MACC1, a process also reduced by miR-378a-3p treatment. Fecal microbiome analysis identified several bacterial species including Akkermansia muciniphilia and certain Bacteroides, associated with beneficial effects in the groups treated with both miRNA mimics. Conclusion This study identifies miR-338-3p and miR-378a-3p as modulators of inflammation in an IL-33-dependent manner in CD patients, underscoring their potential as promising targets for treatment of CD.

P0657 Quality of ileocolic resection in Crohn’s disease- A systemic review and meta-analysis

Abstract Background The terminal ileum is the most common site affected by Crohn’s disease and the area most commonly requiring surgical management. Post operatively, there is large heterogeneity between patient outcomes; with a proportion requiring no further medical or surgical management, whilst others will require life-long management with repeated operations. The reason for this remains unclear. Surgical key performance indicators for an ileocolic resection can include: recurrence, rate of anastomotic leak, post-operative complications (Clavien Dindo (CD) >3), length of stay, re-admission rate and mortality. The aim of this study was to evaluate the effects of mode of surgery, the extent of mesenteric excision and the type of anastomosis on the rate of recurrence. Methods A systematic review was conducted following a priori protocol. Covidence software was used to exclude duplicates, screen studies and extract data. Extracted data was analysed. The primary outcome was recurrence rate and the mode of detection. Secondary outcomes were; anastomotic leak, post-operative complications (CD >3), length of stay, readmission rate, mortality and duration of follow up. Combined overall effect size was calculated using SPSS software. The revised Cochrane risk of bias tool and the Newcastle-Ottawa scale were used to assess risk of bias. Results A total of 24 studies were included. Four (three randomised controlled trials (RCTs)) in the mode of surgery group, four in the extent of mesenteric resection group and sixteen (two RCTs) in the type of anastomosis group. In all four studies included in the mode of surgery group, laparoscopic surgery was associated with a shorter length of stay. No difference was observed in the other outcomes, including rate of recurrence. There was no significant correlation between extended versus limited mesenteric excision and the rate of recurrence (p0.307, OR 0.61 (CI95% -.056, 1.77)). Four studies compared Kono-S anastomosis versus non-Kono-S anastomosis. Kono-S anastomosis was associated with a significantly lower recurrence rate (p=0.002, OR 0.62 (CI95% 0.24, 1.01)). There was significant heterogeneity between these studies (p<0.001). Conclusion To date there is no convincing evidence that the mode of surgery, the extent of the mesenteric excision or the type of anastomosis have any significant effect on reducing the occurrence of Crohn’s recurrence at the anastomosis. References N/A