S3341 When It Is Not Inflammatory Bowel Disease: IBD Mimics Presented at IBD Live

Introduction: A group of Inflammatory Bowel Disease (IBD) specialists have been utilizing weekly live video conferences since long before the pandemic in the form of “IBD Live”. Since 2009 the conference has featured robust interactive case discussions between gastroenterologists and colorectal surgeons of multiple academic institutions and now has a global audience of 150-200 per week. Although the majority are IBD cases, there have been a significant number of cases where IBD was not the ultimate diagnosis. Methods: All 106 conferences recorded and archived between May 2018 and June 2021 were reviewed. Of the 215 cases discussed, 183 had an IBD diagnosis including 124 Crohn’s disease (CD), 54 ulcerative colitis (UC) and 5 inflammatory bowel disease unclassified. Results: Of the remaining 32 (14.9%) cases (Table), many were referred to the specialist with a prior diagnosis of IBD. There were 10 cases of colonic inflammation misdiagnosed as UC. These were most commonly drug-induced colitis secondary to immune checkpoint inhibitors, ocrelizumab for multiple sclerosis, and nintedanib for pulmonary fibrosis. Additionally, there were cases of ischemic colitis, idiopathic myointimal hyperplasia of mesenteric veins (IMHMV), segmental colitis associated with diverticulosis (SCAD), and diversion colitis. There were 8 cases of systemic diseases, diagnosed as Common Variable Immunodeficiency (CVID), sarcoidosis and vasculitis, including cases of Henoch–Schönlein purpura and of CHAI (CTLA4 haploinsufficiency with autoimmune infiltrates). There were 6 cases of ileal disorders, ultimately diagnosed as small bowel lymphoma, tuberculosis, Meckel’s diverticulum, appendiceal carcinoid and abdominal actinomyces infection all previously thought to be CD. There were small bowel mucosal disorders including collagenous sprue and autoimmune enteropathy, and 2 polyposis cases secondary to Cronkhite-Canada and juvenile polyposis syndromes. Finally, there were 3 cases where no consensus diagnosis could be made, with broad differential diagnoses including cryptogenic multifocal ulcerous stenosis enteritis (C-MUSE). Conclusion: At a global IBD webinar in a 3-year period, 14.9% of cases presented highlights the vital importance of awareness of IBD mimics. Patients may carry a diagnosis of IBD for many years prior to being correctly diagnosed and managed. This can have significant implications on quality of life and harm reduction with potential for avoidance of biological therapies used in the management of IBD.Table 1.: IBD Mimics presented at IBD live 2018-2021 Abbreviations: IMHMV - idiopathic myointimal hyperplasia of mesenteric veins; SCAD – segmental colitis associated with diverticulitis; CMV – cytomegalovirus; CVID – common variable immunodeficiency; CHAI - CTLA4 haploinsufficiency with autoimmune infiltrates; TB – tuberculosis; C-MUSE - cryptogenic multifocal ulcerous stenosis

Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.