Lazarev, Mark

Abstract Background Since 2009, inflammatory bowel disease (IBD) specialists have utilized “IBD LIVE,” a weekly live video conference with a global audience, to discuss the multidisciplinary management of their most challenging cases. While most cases presented were confirmed IBD, a substantial number were diseases that mimic IBD. We have categorized all IBD LIVE cases and identified “IBD-mimics” with consequent clinical management implications. Methods Cases have been recorded/archived since May 2018; we reviewed all 371 cases from May 2018–February 2023. IBD-mimics were analyzed/categorized according to their diagnostic and therapeutic workup. Results Confirmed IBD cases made up 82.5% (306/371; 193 Crohn’s disease, 107 ulcerative colitis, and 6 IBD-unclassified). Sixty-five (17.5%) cases were found to be mimics, most commonly medication-induced (n = 8) or vasculitis (n = 7). The evaluations that ultimately resulted in correct diagnosis included additional endoscopic biopsies (n = 13, 21%), surgical exploration/pathology (n = 10, 16.5%), biopsies from outside the GI tract (n = 10, 16.5%), genetic/laboratory testing (n = 8, 13%), extensive review of patient history (n = 8, 13%), imaging (n = 5, 8%), balloon enteroscopy (n = 5, 8%), and capsule endoscopy (n = 2, 3%). Twenty-five patients (25/65, 38%) were treated with biologics for presumed IBD, 5 of whom subsequently experienced adverse events requiring discontinuation of the biologic. Many patients were prescribed steroids, azathioprine, mercaptopurine, or methotrexate, and 3 were trialed on tofacitinib. Conclusions The diverse presentation of IBD and IBD-mimics necessitates periodic consideration of the differential diagnosis, and reassessment of treatment in presumed IBD patients without appropriate clinical response. The substantial differences and often conflicting treatment approaches to IBD versus IBD-mimics directly impact the quality and cost of patient care.

Objective Perianal Crohn’s disease (pCD) occurs in up to 40% of patients with CD and is associated with poor quality of life, limited treatment responses and poorly understood aetiology. We performed a genetic association study comparing CD subjects with and without perianal disease and subsequently performed functional follow-up studies for a pCD associated SNP in Complement Factor B ( CFB ). Design Immunochip-based meta-analysis on 4056 pCD and 11 088 patients with CD from three independent cohorts was performed. Serological and clinical variables were analysed by regression analyses. Risk allele of rs4151651 was introduced into human CFB plasmid by site-directed mutagenesis. Binding of recombinant G252 or S252 CFB to C3b and its cleavage was determined in cell-free assays. Macrophage phagocytosis in presence of recombinant CFB or serum from CFB risk, or protective CD or healthy subjects was assessed by flow cytometry. Results Perianal complications were associated with colonic involvement, OmpC and ASCA serology, and serology quartile sum score. We identified a genetic association for pCD (rs4151651), a non-synonymous SNP (G252S) in CFB , in all three cohorts. Recombinant S252 CFB had reduced binding to C3b, its cleavage was impaired, and complement-driven phagocytosis and cytokine secretion were reduced compared with G252 CFB. Serine 252 generates a de novo glycosylation site in CFB. Serum from homozygous risk patients displayed significantly decreased macrophage phagocytosis compared with non-risk serum. Conclusion pCD-associated rs4151651 in CFB is a loss-of-function mutation that impairs its cleavage, activation of alternative complement pathway, and pathogen phagocytosis thus implicating the alternative complement pathway and CFB in pCD aetiology.

AbstractBackgroundThe safety of a third dose of SARS-CoV-2 mRNA vaccination in patients with inflammatory bowel disease is unknown.MethodsWe compared symptoms following a third SARS-CoV-2 mRNA vaccine dose with symptoms after the second dose in IBD.ResultsThe study group included 594 patients (70% female, 58% BNT162b2). Overall, 41% reported symptoms after a third dose. Symptom frequency and severity were lower after the third dose relative to the second dose for every organ system, except for gastrointestinal symptoms which were marginally worse.ConclusionThe frequency and severity of symptoms after a third mRNA vaccine dose are generally similar or milder than after a second dose for most organ systems.

Abstract Background and study aims In patients with inflammatory bowel disease (IBD), endoscopically visible lesions with distinct borders can be considered for endoscopic resection. The role of endoscopic submucosal dissection (ESD) for these lesions is not well defined because of a paucity of data. We aimed to evaluate the outcomes of colorectal ESD of dysplastic lesions in patients with IBD across centers in the United States. Patients and methods This was a retrospective analysis of consecutive patients with IBD who were referred for ESD of dysplastic colorectal lesions at nine centers. The primary endpoints were the rates of en bloc resection and complete (R0) resection. The secondary endpoints were the rates of adverse events and lesion recurrence. Results A total of 45 dysplastic lesions (median size 30mm, interquartile range [IQR] 23 to 42 mm) in 41 patients were included. Submucosal fibrosis was observed in 73 %. En bloc resection was achieved in 43 of 45 lesions (96 %) and R0 resection in 34 of 45 lesions (76 %). Intraprocedural perforation occurred in one patient (2.4 %) and was treated successfully with clip placement. Delayed bleeding occurred in four patients (9.8 %). No severe intraprocedural bleeding or delayed perforation occurred. During a median follow-up of 18 months (IQR 13 to 37 months), local recurrence occurred in one case (2.6 %). Metachronous lesions were identified in 11 patients (31 %). Conclusions ESD, when performed by experts, is safe and effective for large, dysplastic colorectal lesions in patients with IBD. Despite the high prevalence of submucosal fibrosis, en bloc resection was achieved in nearly all patients with IBD undergoing ESD. Careful endoscopic surveillance is necessary to monitor for local recurrence and metachronous lesions after ESD.