Journal of the Canadian Association of Gastroenterology最新文献

{"title":"A265 BARRIERS TO DIETARY MODIFICATION IN INFLAMMATORY BOWEL DISEASE (IBD): A MIXED-METHODS ASSESSMENT OF PATIENT PERCEPTIONS","authors":"J. Szeto, C. V. Noejovich, R. Verma, P. Miranda, M. Pinto-Sanchez, Eduardo Verdu, D. Armstrong","doi":"10.1093/jcag/gwad061.265","DOIUrl":"https://doi.org/10.1093/jcag/gwad061.265","url":null,"abstract":"Abstract Background Many patients living with IBD identify diet as a key factor in managing their disease, symptoms and general health, and many report implementing dietary restrictions in response to disease activity and symptoms. Despite increasing data on the role of diet, IBD patients face a variety of challenges that can compromise adherence to dietary recommendations in clinical practice. Aims To identify IBD patients’ perceptions regarding barriers to dietary modification and to understand their experiences and expectations of dietary advice from gastroenterologists (GI) or dietitians (RD). Methods A mixed-method qualitative data collection strategy with semi-structured focus group and individual one-on-one interviews moderated by a clinical psychologist over a web-based, video communication platform (Zoom). Adult IBD patients (between 18 to 75 years old) attending the McMaster University Medical Centre IBD Clinic were invited to join a focus group consisting of 2-6 individuals or a one-on-one interview. All participants were asked to complete a demographics survey (REDCap) before the session. Recorded audio files for all sessions were transcribed, de-identified and reviewed for accuracy by 2 reviewers with an independent adjudicator to resolve discrepancies followed by thematic analysis (NVIVO). Results Between May to December 2022 and May 2023, 38 of 90 invitees took part in 11 focus groups and 9 chose individual interviews. Most participants (mean age 42 years; 60% female) were Caucasian (87%); 42% had a self-reported history of mental health disorders. Mean IBD duration was 16 years (min-max: 0.5–44 years); 73% were in remission and 68% had Crohn’s disease. Thematic analysis identified 5 primary and 11 secondary barriers to dietary adoption (Table). Participants reported positive and negative experiences with dietary advice from GIs and RDs; expectations included GI referral to a specialist RD and integration of an RD into the health care team. Conclusions IBD patients report multiple, varied barriers to dietary adoption and identify a need for improved access to dietary advice and other resources, including integration of RDs into primary and IBD Clinic care teams. The identification of multiple, varied patient-reported barriers offers an opportunity to develop personalized dietary advice for IBD patients to enhance health, well-being and quality of life. Thematic map of barriers experienced by patients when adopting dietary modifications Primary Barriers Secondary Barriers Difficulty identifying foods or diets affecting IBD Lack of guidance in identifying foods or diets Difficulty correlating symptoms with diet Barriers to accessing IBD diet foods Limited availability of IBD-friendly food options Expense of speciality food items Psychological Factors Anxiety in relation to food Aversive attitude to food Personal struggles with diet adherence Challenges with diet protocol complexity Changing habits and lifestyle Avoiding food cravings","PeriodicalId":508018,"journal":{"name":"Journal of the Canadian Association of Gastroenterology","volume":"111 3","pages":"213 - 214"},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139838632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A271 EFFECT OF ANTI-TNF AGENTS ON DNA METHYLATION IN PERIPHERAL BLOOD OF PATIENTS WITH INFLAMMATORY BOWEL DISEASE","authors":"J. Venner, J. Francis, J. Rumore, M. Sargent, M Jones, C. Bernstein","doi":"10.1093/jcag/gwad061.271","DOIUrl":"https://doi.org/10.1093/jcag/gwad061.271","url":null,"abstract":"Abstract Background Despite the success and ongoing use of tumor necrosis factor inhibitors (TNFi) in the treatment of inflammatory bowel disease (IBD), there are no predictors of response to therapy. While much research has gone into understanding genetic risks for IBD, less work has been done exploring epigenetic associations with treatment. Hence, we wondered whether epigenetic changes were associated with failure of TNFi in IBD. Aims Describe the association of TNFi response with DNA methylation in patients with IBD. Methods Participants ≥18 years with IBD (N=169) were selected from the Inflammation, Microbiome, and Alimentation: Gastro-Intestinal and Neuropsychiatric Effects (IMAGINE) Strategy for Patient Oriented Research (SPOR) Network. At enrollment participants completed a questionnaire that included their disease diagnosis, therapy, smoking history, and disease activity using the validated IBD Symptom Inventory (IBDSI). Patients provided whole blood samples that were processed for and run on Illumina DNA methylation arrays. Results The 169 patients were in three treatment groups: TNFi naïve (N=98, never exposed to an anti-TNF agent), TNFi responder (N=32, inactive disease on anti-TNF agent), and TNFi nonresponder (N=39, active disease not on any biologic at time of enrollment). The mean symptom score (SIBDSI) was different across the three groups (pampersand:003C0.001): TNFi nonresponders having a higher SIBDSI (24 ± 6.1) than the TNFi naïve (9.1 ± 5.5) or responder (8.3 ± 4.3) treatment groups. Relative proportions of leukocyte populations were estimated using DNA methylation. CD4 and CD8 T cell and B cell counts were higher (pampersand:003C0.05) in the nonresponders and responders versus TNFi naïve group. Neutrophil counts were lower (pampersand:003C0.05) in the TNFi nonresponders and responders compared to the TNFi naïve group (Figure 1). There was a trend towards increased epigenetic estimates of age acceleration (pampersand:003E0.05) in nonresponders versus responders and TNFi naïve patients, likely driven by disease activity (data not shown). Epigenome-wide analysis of the three groups revealed 16 CpGs for responder versus naïve (e.g. CDK5 regulatory subunit-associated protein 1-like 1 (CDKAL1), and two CpGs for nonresponders versus responders (Table 1). This includes a CpG for guanine nucleotide-binding protein subunit gamma-2 (GNG2) that was shared between the two comparisons. Conclusions Exposure to TNFi is associated with changes in peripheral leukocyte populations independent of response to treatment, indicating a TNFi effect. This implies that anti-TNF treatment is having some effect on patients even if there is clinical nonresponse. Differentially expressed CpGs implicates possible markers of response to treatment, particularly CDKAL1, a gene that has been associated with TNFi response in psoriasis. Funding Agencies Guts and Roses Charity","PeriodicalId":508018,"journal":{"name":"Journal of the Canadian Association of Gastroenterology","volume":"31 ","pages":"218 - 219"},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139838689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A107 ANALYSIS OF THE EFFICACY IN TRANSITIONING FROM FOBT TO FIT FOR COLORECTAL CANCER SCREENING AT A SINGLE CENTRE IN ONTARIO","authors":"A Nguyen, G. Porwal","doi":"10.1093/jcag/gwad061.107","DOIUrl":"https://doi.org/10.1093/jcag/gwad061.107","url":null,"abstract":"Abstract Background Colonoscopy is the gold standard for detecting colorectal cancer (CRC) and advanced lesions, but is an invasive and carries some risks, with limited availability and accessibility. Alternatively, the fecal occult blood test (FOBT) and fecal immunochemical test (FIT) are both non-invasive, cost-effective screening tests that can also be used to detect CRC, advanced lesions, and polyps, identifying individuals to be prioritized to undergo colonoscopy. FOBT screens for small amounts of blood in stool by detecting heme through a chemical reaction. FIT confirms the presence of blood in stool by using antibodies to detect hemoglobin. Prior to 2019, Ontario employed FOBT as the preferred method for CRC screening in eligible individuals. In early 2019, Ontario transitioned to FIT as the preferred screening test, due its established superior test performance for identifying patients with high risk lesions for colon cancer. Aims This single-centre retrospective study analyzed the change in efficacy of detecting advanced lesions, when transitioning from FOBT to FIT, as identified on subsequent colonoscopy Methods A retrospective chart review was conducted of approximately 1000 patients undergoing colonoscopy for FOBT or FIT at Cambridge Memorial Hospital, covering the period of transition from FOBT to FIT. Colonoscopies were performed by 10 endoscopists. Patients were stratified into 2 groups based on fecal test type, FOBT (N = 344) and FIT (N = 572). Overall and individual proportions of cancer, polyps, adenomas, advanced adenomas (AA), and sessile serrated adenomas (SSA) detection in the subsequent colonoscopies were calculated for both groups. The efficacy of both tests was then assessed using statistical analysis. Results In total, 344 patients were included for FOBT analysis and results included: cancer (5.52%), any polyp (56.69%), adenoma (43.6%), AA (20.64), and SSA (6.1%). In contrast, 572 patients were included for analysis of FIT group and results included: cancer (3.85%), any polyp (83.22%), adenoma (76.92%), AA (43.01), and SSA (12.94%). Cancer detection was similar in the 2 groups. There was significant improvement in polyp, adenoma, advanced adenoma, and sessile serrated adenoma detection with FIT compared to FOBT. This improvement was consistent in all endoscopists, but more pronounced in endoscopists with lower detection rates in FOBT cases. Conclusions The use of FIT as a screening stool test, as compared to FOBT, was associated with a significantly improved detection for polyps, adenomas, AA, and SSA, confirming greater accuracy and sensitivity of FIT as a screening tool. This result confirms the premise, at least at a single institution, that by switching to FIT, Ontario has improved colon cancer screening and prevention with more efficient and higher yield utilization of a limited and costly health care resource Funding Agencies None","PeriodicalId":508018,"journal":{"name":"Journal of the Canadian Association of Gastroenterology","volume":"129 2","pages":"78 - 79"},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139838762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A189 INVESTIGATING THE ROLE OF BACTERIAL HISTAMINE METABOLISM IN VISCERAL HYPERALGESIA","authors":"T. Ross, J. Pujo, M. Hall-Bruce, S Collins, S. Vanner, D E Reed, P. Bercik, G. De Palma","doi":"10.1093/jcag/gwad061.189","DOIUrl":"https://doi.org/10.1093/jcag/gwad061.189","url":null,"abstract":"Abstract Background Intestinal microbiota have been implicated in the expression of irritable bowel syndrome (IBS) as patients present with altered gut microbial profiles and microbial metabolic activity. We have previously identified bacterial histamine to strongly influence mast cell accumulation through only IBS activation of the H4 receptor, leading to visceral hyperalgesia in a subset of patients with IBS. We hypothesize that a subset of IBS patients with high histamine-producing microbiota exhibit an aberrant histamine metabolism. Investigating the microbiota-driven pathways involved in histamine metabolism is key to understanding abdominal pain pathophysiology in IBS patients. Aims 1. To study whether variations of histamine levels are due to bacterial metabolism using in vitro and in vivo approaches. 2. To identify the prevalence of high histamine-producing and histamine-degrading bacteria in a clinical cohort via in silico analyses. Methods Using in vitro approaches, stool samples from healthy control (HC) donors and IBS patients were inoculated in minimal media in aerobic/anaerobic conditions, with/without excess histidine or added histamine. Bacterial histamine production and degradation were assessed in culture supernatants by ELISA. After identification through Sanger sequencing, individual colony capacity to degrade and produce histamine was assessed. Host and microbial contributions to histamine metabolism will be identified through analyses of germ-free mice colonized with IBS and HC stool samples. Results IBS patients (n=23) tested were found to consistently produce higher levels of histamine compared to HC (n=3). Among the tested isolated colonies from IBS patients (n=179) 61% produced histamine compared to 33% of HC (n=54), and 20% degraded histamine compared to 11% of HC. Of these colonies, 13% of only IBS isolates demonstrated the capacity to both degrade and produce histamine. Facultative anaerobes were found to possess both higher production and degradation capacity. Both pH and histamine concentration determine bacterial ability to produce or degrade histamine. Conclusions Based on these findings, both healthy and IBS individuals exhibit varying levels of histamine production/degradation, most prominently through facultative anaerobes. The intestinal environment and bacterial community composition are major regulators of bacterial histamine metabolism. The observed in vitro capacity to produce/degrade histamine, and its biological implications, will be confirmed with gnotobiotic humanized mice, ultimately aiding in designing microbiota-directed therapies for the management of visceral hypersensitivity. Funding Agencies CIHRFarncombe Innovation Fund","PeriodicalId":508018,"journal":{"name":"Journal of the Canadian Association of Gastroenterology","volume":"749 ","pages":"148 - 149"},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139839005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A165 MALIGNANT TUMORS OF THE SMALL BOWEL DIAGNOSED BY DOUBLE BALLOON ENTEROSCOPY: A FIFTEEN-YEAR EXPERIENCE OF A MEDICAL CENTER IN MID-TAIWAN","authors":"WU Y., J. Chou","doi":"10.1093/jcag/gwad061.165","DOIUrl":"https://doi.org/10.1093/jcag/gwad061.165","url":null,"abstract":"Abstract Background The malignant tumors of the small bowel are relatively rare, and their pre-operative diagnosis is usually difficult Aims This study was aimed to investigate the clinical characteristics of patients with malignant small bowel tumors who underwent double balloon enteroscopy. Secondary end points were to evaluate the usefulness and safety of double balloon enteroscopy for the diagnosis of patients with suspected small bowel tumors derived from other previous procedures. Methods From January 2008 to June 2023, we retrospectively analyzed consecutive patients who underwent double balloon enteroscopy at a medical center in mid-Taiwan over a 15-year period (Figure 1). Results Double balloon enteroscopy were performed in 1001 patients. Small bowel tumors were diagnosed in 141 patients (141/1001; 14.1%), of which 76 patients (53.9%) (43 males, a mean age of 61.89 years) had malignant tumors : 37 had gastrointestinal stromal tumors (49.4%), 16 had adenocarcinoma (20.8%), 10 had metastatic cancer (13.1%), 7 had lymphoma (9.2%), 3 had angiosarcoma (3.9%), 2 had carcinoid (2.6%), and 1 had desmoid tumor (1.3%) (Figure 2). The indications for double-balloon enteroscopy in patients with malignant small bowel tumors were obscure gastrointestinal bleeding (68.4%). The concordance rate of diagnoses based on double balloon enteroscopy with diagnoses based on small bowel barium study, computed tomography, and capsule endoscopy among patients with small bowel tumors was 54.1%, 65.9% , and 76.9%, respectively. (Figure 3, 4) . Therapeutic plans were changed to surgery in 67.1 % of patients with malignant small bowel tumors. Additionally, treatment was added on chemotherapy in 25.6% of patients with malignant small bowel tumors after the results of double-balloon enteroscopy. Conclusions Approximately 14.1% of patients who underwent double balloon enteroscopy had small bowel tumors, 53.9% of small bowel tumors are malignant. The most common indication for double balloon enteroscopy in patients with malignant small bowel tumors was obscure gastrointestinal bleeding. Double balloon enteroscopy is a very useful modality in diagnosing malignant small bowel tumors and has an important impact on therapeutic plans and clinical results. Figure 1. The Prevalence Rate of Small Bowel Tumor Figure 2. Malignant tumor Figure 3. Location Distribution of Small Bowel Tumors Figure 4. The clinical manifestations of Malignancy Tumors Funding Agencies None Intestinal Disorders","PeriodicalId":508018,"journal":{"name":"Journal of the Canadian Association of Gastroenterology","volume":"536 2","pages":"128 - 129"},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139839028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A253 BEHAVIOUR CHANGE CONSIDERATIONS TO IMPROVE PHYSICAL ACTIVITY PARTICIPATION AMONG INDIVIDUALS WITH QUIESCENT AND MILDLY ACTIVE IBD – A QUALITATIVE STUDY","authors":"B. Oketola, S. Webber, H Singh, M. Kredentser, K. Reynolds, G. Restall","doi":"10.1093/jcag/gwad061.253","DOIUrl":"https://doi.org/10.1093/jcag/gwad061.253","url":null,"abstract":"Abstract NOT PUBLISHED AT AUTHOR’S REQUEST Please acknowledge all funding agencies listed below Funding Agencies CAGPfizer","PeriodicalId":508018,"journal":{"name":"Journal of the Canadian Association of Gastroenterology","volume":"521 5","pages":"203 - 204"},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139839053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A5 DEVELOPMENT OF A PRE-CLINICAL MOUSE MODEL TO INVESTIGATE ADVERSE FOOD REACTIONS IN INTESTINAL INFLAMMATION","authors":"B. Barbosa da Luz, L. Rondeau, R. Dang, A. Caminero","doi":"10.1093/jcag/gwad061.005","DOIUrl":"https://doi.org/10.1093/jcag/gwad061.005","url":null,"abstract":"Abstract Background Patients with chronic intestinal conditions, including inflammatory bowel disease (IBD), experience diverse food-related adverse reactions. However,, the precise mechanisms of food intolerances in IBD remains unclear. Emerging evidence suggests that altered diet-microbiota interactions can contribute to the development of IBD. Previously we shown that intestinal microbiota plays an important role in the development of food intolerances. We hypothesize that microbial alterations in IBD patients facilitate adverse reactions to foods. Aims To establish a preclinical mouse model to study adverse food reactions in intestinal inflammation. Methods Eight-week-old C57BL/6 mice were treated with 3% dextran sodium sulfate (DSS) for 5 days, then divided into three groups. The first group was sensitized to dairy protein (3% casein and 3% whey), using 4 oral administrations of cholera toxin over 2 weeks, without any further diet intervention. The second group was also sensitized to casein and whey, then after 1 week of recovery, the mice were subsequently place on a chow containing casein and whey. Finally, the third group was subjected to diet intervention without sensitization. The same experiment was repeated in a different subset of C57BL/6 mice which included a second cycle of DSS (1.5%) during the dietary interventions. Markers of intestinal inflammation (disease activity index (DAI), histological damage, cell infiltration and pro-inflammatory genes expression (NanoString)) and intestinal microbiota were analysed after 1 week of the diet intervention. Results Mice previously sensitized on the dairy diet exhibited an enhanced activation of immune cells after intestinal inflammation. While the histological damage score did not reveal significant differences among experimental groups, the sensitized group under dairy intervention exhibited an elevated level of immune cell infiltration, increasing the polymorphonuclear, CD3+ and mast cells. Gene expression also revealed that dairy induced the expression of inflammatory genes, such as C6, Arg1, Tnf, Il6, Cxcl9 and Cxcl10. When animals are subjected to a second DSS-cycle, dairy worsen colitis in mice previously sensitized, as shown by higher DAI compared to group with control diet and dairy diet without sensitization. Conclusions In the context of intestinal inflammation, dairy protein leads to immune activation characterized by an increase in polymorphonuclear cells, mast cells and lymphocytes, as well as worsening colitis. Future studies using this model will provide valuable insights into the role of intestinal microbiota in food intolerances associated with intestinal inflammation. Funding Agencies CCC","PeriodicalId":508018,"journal":{"name":"Journal of the Canadian Association of Gastroenterology","volume":"504 1","pages":"3 - 3"},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139839059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A196 CSF2 AUTOANTIBODIES AS A SEROLOGICAL MARKER FOR CROHN'S DISEASE","authors":"S. Tai, D. Del Valle, R. Urango, K. Croitoru, S. Gnjatic, J. Korzenik, J. Colombel, A. Mortha","doi":"10.1093/jcag/gwad061.196","DOIUrl":"https://doi.org/10.1093/jcag/gwad061.196","url":null,"abstract":"Abstract Background Crohn’s disease (CD) is a chronic inflammatory disorder of the gastrointestinal tract that severely affects quality of life. Despite technological advances, CD diagnoses remain difficult and invasive, with delayed diagnoses correlated with worse prognosis and complications. CD is multifactorial, involving complex interactions between genetic and environmental risk factors, which leads to difficulty in identifying a cause and cure. However, research alludes to an underlying dysregulation of immune activity that leads to chronic intestinal inflammation. Mononuclear phagocytes (MNP) are essential immune cells that promote intestinal homeostasis through supporting immune tolerance, antimicrobial activity, and barrier integrity. A crucial cytokine that promotes the survival and function of intestinal MNP is Colony Stimulating Factor 2 (CSF2). Intriguingly, previous work in our lab demonstrated that CSF2 autoantibodies (CSF2-Ab) can be detected in the serum of every third CD patient and antedate the onset of CD by up to 6 years. In contrast, these titers are not seen in healthy donors or ulcerative colitis. Moreover, CSF2-Ab were predictive of disease location and severity, and are able to neutralize CSF2 by binding to glycosylations, impacting downstream signaling in MNP. These data suggest a role for CSF2-Ab in promoting intestinal immune dysregulation in CD. Aims Our work aims to characterize CSF2-Ab and their role in CD. Methods We developed a bead-based flow cytometric assay to screen CD patient serum for CSF2-Ab in several cohorts that contain samples at time points prior to, at, and after diagnosis. Results Our preliminary data demonstrate that our assay is rapid and specific for detecting CSF2-Ab of various isotypes in human serum and can be validated using ELISA. Furthermore, we show that this assay can be used to determine the epitope specificity of CSF2-Ab in CD patients in just one single sample. Conclusions We have developed a rapid and accessible assay to predict CD development years before diagnosis using minimal serum samples. Moreover, this screen will enable subclassification of patients based on their autoantibody reactivity to glycovariants of CSF2. Glycovariants that escape recognition by CD-specific CSF2-Ab could potentially be used as a therapeutic to ameliorate disease. Beyond treatment, understanding how CSF2-Ab epitope specificity and isotypes may change over the course of disease development will serve as a roadmap for elucidating the role of CSF2-Ab in CD. Funding Agencies CAG, CIHR","PeriodicalId":508018,"journal":{"name":"Journal of the Canadian Association of Gastroenterology","volume":"415 1","pages":"154 - 155"},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139839337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A297 EXAMINING THE IMPACT OF INFLAMMATORY BOWEL DISEASE IN PRIMARY SCLEROSING CHOLANGITIS PATIENTS POST LIVER TRANSPLANTATION","authors":"G. Malhi, L. A. Diaz, G. Punchhi, R. Mortuza, M Khan, M. Brahmania, V. Jairath, J. Arab","doi":"10.1093/jcag/gwad061.297","DOIUrl":"https://doi.org/10.1093/jcag/gwad061.297","url":null,"abstract":"Abstract Background Primary sclerosing cholangitis (PSC) is an immune-mediated disease that is characterized by biliary inflammation and fibrosis. It is associated with inflammatory bowel disease (IBD) in 80% of cases. To date, the impact of IBD in liver transplantation (LT) recipients is not completely understood. Aims To assess the impact of IBD in individuals with PSC who underwent liver transplantation (LT) in terms of graft survival, infections, and mortality. Methods This was a retrospective cohort study that included individuals with PSC who received a LT between 1999–2021. Statistical analysis included Kaplan-Meier survival curves, a binary logistic regression to estimate infection risk, and a competing-risk analysis to estimate post-LT mortality (with re-transplantation being a competing risk). Results 122 LT recipients were included. Mean age at LT was 44.9±12.6 years old. The median MELD-Na at LT was 22 [17–28]. Twenty-nine (23.8%) LT recipients died during follow-up (median 1,248 [413–3,857] days) and 5 (4.1%) required re-transplantation (median 1,460 [923–2,563] days). Estimated graft survival was 93.2% (95%CI: 86.9%–96.6%) at 1 year and 81.3% (95%CI: 72.5%–87.6%) at 5 years. An adjusted competing-risk model demonstrated that increasing age (sHR 1.05, 95%CI: 1.01–1.10; p=0.018), baseline MELD-Na (sHR 1.07, 95%CI: 1.02–1.12; p=0.005), and ERCP requirements before LT (sHR 6.33; 95%CI: 1.63–24.65; p=0.008) were associated with higher post-LT mortality, while IBD was not associated with post-LT mortality (sHR 1.02, 95%CI: 0.38–2.70; p=0.962). The incidence of infections after LT was 50.8% at 30 days. IBD was not associated with development of infections at 30 days (OR 1.01, 95%CI: 0.98–1.04; p=0.615) post-LT. Conclusions Based on this retrospective review, an older age, higher MELD-Na at LT and prior ERCP requirements were independently associated with a higher mortality post-LT in PSC patients. However, a background history of IBD was not associated with higher mortality or with infections post-LT. Table 1: Baseline Demographics Category Number (%) PSC 122 (100) Classic PSC 104 (85.3) PSC-AIH Overlap 17 (13.9) Small Duct PSC 1 (0.8) Age ampersand:003C30 17 (13.9) 30-50 59 (48.4) ampersand:003E50 46 (37.7) Sex Male 91 (74.6) Female 31 (25.4) IBD History IBD Present 99 (81.2) No IBD 23 (18.8) Funding Agencies None","PeriodicalId":508018,"journal":{"name":"Journal of the Canadian Association of Gastroenterology","volume":"163 ","pages":"240 - 242"},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139839391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A15 LEVERAGING CULTURE-DEPENDENT AND -INDEPENDENT METAGENOMICS TO IDENTIFY ENTEROBACTERIACEAE GENES ASSOCIATED WITH ACTIVE ULCERATIVE COLITIS","authors":"D. Tertigas, F. Rinawi, P. Moayyedi, A. Griffiths, M. Surette","doi":"10.1093/jcag/gwad061.015","DOIUrl":"https://doi.org/10.1093/jcag/gwad061.015","url":null,"abstract":"Abstract Background Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) that is restricted to the large intestine and is characterized by mucosal inflammation. There is evidence that pathogenic bacteria contribute to UC pathogenesis in at least some patients and the bacterial family Enterobacteriaceae are prime suspects. Some strains of Enterobacteriaceae carry virulence genes important for colonizing the gut (e.g. fimH) and disrupting the intestinal epithelium (e.g. hemolysins). We hypothesize that key virulence genes carried by strains of many Enterobacteriaceae species contribute to disease activity in some UC patients. As we predict virulence genes are strain-specific, the detection of the species alone (e.g. Escherichia coli) is insufficient to predict pathogenic potential and this has confounded previous studies to identify infectious agents in UC. Aims We aim to use culture-dependent and -independent sequencing approaches to identify Enterobacteriaceae genes in the UC gut microbiome associated with active disease. Methods UC patient stool samples collected throughout enrolment in randomized control trials of fecal microbiota transplantation (FMT) for adult UC (n=10) and microbiome studies in early-onset pediatric UC (n=25) were cultured on MacConkey (MAC) agar to enrich for Enterobacteriaceae. Strains were isolated from baseline stool samples cultured on MAC agar for whole genome sequencing and virulence gene characterization. Baseline and post-treatment stool samples cultured on MAC agar were sent for metagenomic sequencing. Using a subset of 11 pediatric patients, I developed a metagenomic pipeline to identify Enterobacteriaceae genes enriched during active UC compared to periods of remission or milder disease. Results Known virulence genes, including fimH and hemolysins, were present in some strains across multiple Enterobacteriaceae species. Using an unbiased metagenomic approach with the pediatric cohort, we identified 42 genes enriched at baseline with the criteria they must be elevated in at least three of the 11 patients. The majority of the 42 genes were distributed into six gene clusters, including a small plasmid. Conclusions Our approach allows us to identify genes enriched in active UC that have not been previously described in the literature and our analysis will be repeated with our adult cohort. Genes that are enriched in active UC in the pediatric and/or adult cohort will be validated in publicly available metagenomic datasets that consist of both IBD patients and healthy controls. Furthermore, culture-dependent approaches allow us to test mechanisms in vivo that are informed by our bioinformatics. Leveraging microbiome and clinical data provides a unique window to guide future diagnostics and treatments to improve outcomes for UC patients. Funding Agencies CIHROGS","PeriodicalId":508018,"journal":{"name":"Journal of the Canadian Association of Gastroenterology","volume":"396 2","pages":"8 - 9"},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139839465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}