Multimodal single-cell datasets characterize antigen-specific CD8+ T cells across SARS-CoV-2 vaccination and infection.

The immune response to SARS-CoV-2 antigen after infection or vaccination is defined by the durable production of antibodies and T cells. Population-based monitoring typically focuses on antibody titer, but there is a need for improved characterization and quantification of T cell responses. Here, we used multimodal sequencing technologies to perform a longitudinal analysis of circulating human leukocytes collected before and after immunization with the mRNA vaccine BNT162b2. Our data indicated distinct subpopulations of CD8+ T cells, which reliably appeared 28 days after prime vaccination. Using a suite of cross-modality integration tools, we defined their transcriptome, accessible chromatin landscape and immunophenotype, and we identified unique biomarkers within each modality. We further showed that this vaccine-induced population was SARS-CoV-2 antigen-specific and capable of rapid clonal expansion. Moreover, we identified these CD8+ T cell populations in scRNA-seq datasets from COVID-19 patients and found that their relative frequency and differentiation outcomes were predictive of subsequent clinical outcomes.

IL-17RA-signaling in Lgr5+ intestinal stem cells induces expression of transcription factor ATOH1 to promote secretory cell lineage commitment.

The Th17 cell-lineage-defining cytokine IL-17A contributes to host defense and inflammatory disease by coordinating multicellular immune responses. The IL-17 receptor (IL-17RA) is expressed by diverse intestinal cell types, and therapies targeting IL-17A induce adverse intestinal events, suggesting additional tissue-specific functions. Here, we used multiple conditional deletion models to identify a role for IL-17A in secretory epithelial cell differentiation in the gut. Paneth, tuft, goblet, and enteroendocrine cell numbers were dependent on IL-17A-mediated induction of the transcription factor ATOH1 in Lgr5+ intestinal epithelial stem cells. Although dispensable at steady state, IL-17RA signaling in ATOH1+ cells was required to regenerate secretory cells following injury. Finally, IL-17A stimulation of human-derived intestinal organoids that were locked into a cystic immature state induced ATOH1 expression and rescued secretory cell differentiation. Our data suggest that the cross talk between immune cells and stem cells regulates secretory cell lineage commitment and the integrity of the mucosa.

The γδ IEL effector API5 masks genetic susceptibility to Paneth cell death.

Loss of Paneth cells and their antimicrobial granules compromises the intestinal epithelial barrier and is associated with Crohn's disease, a major type of inflammatory bowel disease1-7. Non-classical lymphoid cells, broadly referred to as intraepithelial lymphocytes (IELs), intercalate the intestinal epithelium8,9. This anatomical position has implicated them as first-line defenders in resistance to infections, but their role in inflammatory disease pathogenesis requires clarification. The identification of mediators that coordinate crosstalk between specific IEL and epithelial subsets could provide insight into intestinal barrier mechanisms in health and disease. Here we show that the subset of IELs that express γ and δ T cell receptor subunits (γδ IELs) promotes the viability of Paneth cells deficient in the Crohn's disease susceptibility gene ATG16L1. Using an ex vivo lymphocyte-epithelium co-culture system, we identified apoptosis inhibitor 5 (API5) as a Paneth cell-protective factor secreted by γδ IELs. In the Atg16l1-mutant mouse model, viral infection induced a loss of Paneth cells and enhanced susceptibility to intestinal injury by inhibiting the secretion of API5 from γδ IELs. Therapeutic administration of recombinant API5 protected Paneth cells in vivo in mice and ex vivo in human organoids with the ATG16L1 risk allele. Thus, we identify API5 as a protective γδ IEL effector that masks genetic susceptibility to Paneth cell death.

Histologic Remission in Inflammatory Bowel Disease and Female Fertility: A Nationwide Study.

BACKGROUND & AIMS: Inflammatory bowel disease (IBD) is linked to reduced female fertility, but it is unclear how fertility rates vary by histologic disease activity. METHODS: Nationwide IBD cohort of Swedish women aged 15 to 44 years. We examined fertility rates during periods with vs without histologic inflammation (n = 21,046; follow-up, 1990-2016) and during periods with vs without clinical activity (IBD-related hospitalization, surgery, or treatment escalation) (n = 24,995; follow-up, 2006-2020). Accounting for sociodemographics and comorbidities, we used Poisson regression to estimate adjusted fertility rate ratios (aFRRs) for live births conceived during 12-month periods of histologic inflammation (vs histologic remission) and 3-month periods of clinically active IBD (vs quiescent IBD). RESULTS: During periods with vs without histologic inflammation, there were 6.35 (95% confidence interval [CI], 5.98-6.73) and 7.09 (95% CI, 6.48-7.70) live births conceived per 100 person-years of follow-up, respectively, or 1 fewer child per 14 women with 10 years of histologic inflammation (aFRR, 0.90; 95% CI, 0.81-1.00). In women with histologic inflammation, fertility was similarly reduced in ulcerative colitis (UC) (aFRR, 0.89 [95% CI, 0.78-1.02]) and Crohn's disease (CD) (aFRR, 0.86 [95% CI, 0.72-1.04]). Clinical IBD activity was associated with an aFRR of 0.76 (95% CI, 0.72-0.79) or 1 fewer child per 6 women with 10 years of clinical activity. Fertility was reduced in clinically active UC (aFRR, 0.75 [95% CI, 0.70-0.81]) and CD (aFRR, 0.76 [95% CI, 0.70-0.82]). Finally, among women with clinically quiescent IBD, histologic inflammation (vs histologic remission) was associated with reduced fertility (aFRR, 0.85 [95% CI, 0.73-0.98]). CONCLUSIONS: An association between histologic and clinical activity and reduced female fertility in CD and UC was found. Notably, histologic inflammation was also linked to reduced fertility in women with clinically quiescent IBD.

Variable susceptibility of intestinal organoid-derived monolayers to SARS-CoV-2 infection.

Gastrointestinal effects associated with Coronavirus Disease 2019 (COVID-19) are highly variable for reasons that are not understood. In this study, we used intestinal organoid-derived cultures differentiated from primary human specimens as a model to examine interindividual variability. Infection of intestinal organoids derived from different donors with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) resulted in orders of magnitude differences in virus replication in small intestinal and colonic organoid-derived monolayers. Susceptibility to infection correlated with angiotensin I converting enzyme 2 (ACE2) expression level and was independent of donor demographic or clinical features. ACE2 transcript levels in cell culture matched the amount of ACE2 in primary tissue, indicating that this feature of the intestinal epithelium is retained in the organoids. Longitudinal transcriptomics of organoid-derived monolayers identified a delayed yet robust interferon signature, the magnitude of which corresponded to the degree of SARS-CoV-2 infection. Interestingly, virus with the Omicron variant spike (S) protein infected the organoids with the highest infectivity, suggesting increased tropism of the virus for intestinal tissue. These results suggest that heterogeneity in SARS-CoV-2 replication in intestinal tissues results from differences in ACE2 levels, which may underlie variable patient outcomes.

AGA Clinical Practice Update on Management of Inflammatory Bowel Disease in Patients With Malignancy: Commentary.

DESCRIPTION: The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update (CPU) Commentary is to discuss the risks of various malignancies in patients with inflammatory bowel diseases (IBD) and the impact of the available medical therapies on these risks. The CPU will also guide the approach to the patient with IBD who develops a malignancy or the patient with a history of cancer in terms of IBD medication management. METHODS: This CPU was commissioned and approved by the AGA Institute CPU committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPU committee and external peer review through standard procedures of Clinical Gastroenterology and Hepatology. This communication incorporates important and recently published studies in the field, and it reflects the experiences of the authors who are experts in the diagnosis and management of IBD.

Histologic Activity in Inflammatory Bowel Disease and Risk of Serious Infections: A Nationwide Study.

BACKGROUND & AIMS: Individuals with inflammatory bowel disease (IBD) are at increased risk of serious infections, but whether this risk varies by histologic disease activity is unclear. METHODS: This was a national population-based study of 55,626 individuals diagnosed with IBD in 1990 to 2016 with longitudinal data on ileocolorectal biopsy specimens followed up through 2016. Serious infections were defined as having an inpatient infectious disease diagnosis in the Swedish National Patient Register. We used Cox regression to estimate hazard ratios (HRs) for serious infections in the 12 months after documentation of histologic inflammation (vs histologic remission), adjusting for social and demographic factors, chronic comorbidities, prior IBD-related surgery, and hospitalization. We also adjusted for IBD-related medications in sensitivity analyses. RESULTS: With histologic inflammation vs remission, there was 4.62 (95% CI, 4.46-4.78) and 2.53 (95% CI, 2.36-2.70) serious infections per 100 person-years of follow-up, respectively (adjusted HR [aHR], 1.59; 95% CI, 1.48-1.72). Histologic inflammation (vs remission) was associated with an increased risk of serious infections in ulcerative colitis (aHR, 1.68; 95% CI, 1.51-1.87) and Crohn's disease (aHR, 1.59; 95% CI, 1.40-1.80). The aHRs of sepsis and opportunistic infections were 1.66 (95% CI, 1.28-2.15) and 1.71 (95% CI, 1.22-2.41), respectively. Overall, results were consistent across age groups, sex, and education level, and remained largely unchanged after adjustment for IBD-related medications (aHR, 1.47; 95% CI, 1.34-1.61). CONCLUSIONS: Histologic inflammation of IBD was an independent risk factor of serious infections, including sepsis, suggesting that achieving histologic remission may reduce infections in IBD. The study was approved by the Stockholm Ethics Review Board (approval numbers 2014/1287-31/4, 2018/972-32, and 2021-06209-01).

Real-World Surgical and Endoscopic Recurrence Based on Risk Profiles and Prophylaxis Utilization in Postoperative Crohn's Disease.

BACKGROUND & AIMS: Preoperative risk stratification may help guide prophylactic biologic utilization for the prevention of postoperative Crohn's disease (CD) recurrence; however, there are limited data exploring and validating proposed clinical risk factors. We aimed to explore the preoperative clinical risk profiles, quantify individual risk factors, and assess the impact of biologic prophylaxis on postoperative recurrence risk in a real-world cohort. METHODS: In this multicenter retrospective analysis, patients with CD who underwent ileocolonic resection (ICR) from 2009 to 2020 were identified. High-risk (active smoking, ≥2 prior surgeries, penetrating disease, and/or perianal disease) and low-risk (nonsmokers and age >50 y) features were used to stratify patients. We assessed the risk of endoscopic (Rutgeert score, ≥i2b) and surgical recurrence by risk strata and biologic prophylaxis (≤90 days postoperatively) with logistic and time-to-event analyses. RESULTS: A total of 1404 adult CD patients who underwent ICR were included. Of the high-risk factors, 2 or more ICRs (odds ratio [OR], 1.71; 95% CI, 1.13-2.57), active smoking (OR, 1.73; 95% CI, 1.17-2.53), penetrating disease (OR, 1.41; 95% CI, 1.02-1.94), and history of perianal disease alone (OR, 1.99; 95% CI, 1.42-2.79) were associated with surgical but not endoscopic recurrence. Surgical recurrence was lower in high-risk patients receiving prophylaxis vs not (10.2% vs 16.7%; P = .02), and endoscopic recurrence was lower in those receiving prophylaxis irrespective of risk strata (high-risk, 28.1% vs 37.4%; P = .03; and low-risk, 21.1% vs 38.3%; P = .002). CONCLUSIONS: Clinical risk factors accurately illustrate patients at risk for surgical recurrence, but have limited utility in predicting endoscopic recurrence. Biologic prophylaxis may be of benefit irrespective of risk stratification and future studies should assess this.

Safety of Immunosuppression in a Prospective Cohort of Inflammatory Bowel Disease Patients With a HIstoRy of CancEr: SAPPHIRE Registry.

BACKGROUND & AIMS: In patients with inflammatory bowel disease (IBD) and a history of cancer, retrospective studies have suggested that exposure to immunosuppressive agents does not increase the risk of incident (recurrent or new) cancer compared with unexposed patients. SAPPHIRE is a prospective registry aimed at addressing this issue. METHODS: Since 2016, patients with IBD and confirmed index cancer before enrollment were followed up annually. Patients receiving chemotherapy or radiation at enrollment, or recurrent cancer within 5 years, were excluded. The primary outcome was development of incident cancer related to exposure to immunosuppressive medications. RESULTS: Among 305 patients (47% male, 88% white), the median age at IBD diagnosis and cancer were 32 and 52 years, respectively. Index cancers were solid organ (46%), dermatologic (32%), gastrointestinal (13%), and hematologic (9%). During a median follow-up period of 4.8 years, 210 patients (69%) were exposed to immunosuppressive therapy and 46 patients (15%) developed incident cancers (25 new, 21 recurrent). In unadjusted analysis, the crude rate of incident cancer in unexposed patients was 2.58 per 100 person-years vs 4.78 per 100 person-years (relative risk, 1.85; 95% CI, 0.92-3.73) for immunosuppression-exposed patients. In a proportional hazards model adjusting for sex, smoking history, age and stage at index malignancy, and nonmelanoma skin cancer, no significant association was found between receipt of immunosuppression and incident cancer (adjusted hazard ratio, 1.41; 95% CI, 0.69-2.90), or with any major drug class. CONCLUSIONS: In this interim analysis of patients with IBD and a history of cancer, despite numerically increased adjusted hazard ratios, we did not find a statistically significant association between subsequent exposure to immunosuppressive therapies and development of incident cancers.

Atherosclerosis as a Risk Factor of Inflammatory Bowel Disease: A Population-Based Case-Control Study.

INTRODUCTION: Data suggest atherosclerotic-related inflammation may play a role in the pathogenesis of inflammatory bowel disease (IBD), but large-scale studies are missing. METHODS: In this nationwide case-control study, we used the Swedish Patient Register and the Epidemiology Strengthened by histoPathology Reports in Sweden cohort to identify adult cases of incident IBD between 2002 and 2021, with each case matched to up to 10 general population controls. We used conditional logistic regression to calculate odds ratios (OR) for exposure to an atherosclerotic-related condition (myocardial infarction, thromboembolic stroke, or atherosclerosis itself) before being diagnosed with IBD. RESULTS: There were a total of 56,212 individuals with IBD and 531,014 controls. Of them, 2,334 (4.2%) cases and 18,222 (3.4%) controls had a prior diagnosis of an atherosclerotic-related condition, corresponding to an OR of 1.30 (95% confidence interval [CI] 1.24-1.37). Results were statistically significant for both Crohn's disease (OR 1.37, 95% CI 1.26-1.48) and ulcerative colitis (OR 1.27, 95% CI 1.20-1.35) and for individuals who developed IBD at 40-59 years of age and 60 years or older. In addition, associations persisted when adjusting for underlying comorbidities, including the presence of immune-mediated diseases and prior aspirin and/or statin use. The highest odds of an atherosclerotic-related condition were seen in the 6-12 months before IBD diagnosis, though odds were increased even ≥5 years before. A higher magnitude of odds was also observed when having 2 or more atherosclerotic-related conditions when compared with having only 1 condition. DISCUSSION: A history of an atherosclerotic-related condition is associated with increased odds of developing IBD, particularly among older adults. Future studies should investigate whether drugs targeting atherosclerotic-related inflammation may prevent IBD in higher-risk individuals.

Outcomes After Fecal Microbiota Transplantation in Combination With Bezlotoxumab for Inflammatory Bowel Disease and Recurrent Clostridioides difficile Infection.

ABSTRACT: Fecal microbiota transplantation (FMT) prevents recurrent Clostridioides difficile infections (rCDI) in patients with inflammatory bowel disease. Bezlotoxumab is also indicated to prevent rCDI. We assess the impact of FMT in combination with bezlotoxumab in patients with inflammatory bowel disease and rCDI. We conducted a multicenter randomized placebo-controlled trial. All received a single colonoscopic FMT. Patients were randomized 1:1 to receive bezlotoxumab or placebo. Sixty-one patients were enrolled (30 received treatment and 31 received placebo). Overall, 5 participants (8%) experienced a CDI recurrence; 4 in the treatment arm, 1 in the placebo arm (13% vs 3%, P = 0.15). There was no clear benefit to the combination approach compared with FMT alone.

Histologic Activity From Neoterminal Ileal Biopsies in Patients With Crohn's Disease in Endoscopic Remission is Associated With Postoperative Recurrence.

INTRODUCTION: Following ileocolic resection (ICR), the clinical importance and prognostic implications of histologic activity on biopsies in Crohn's disease (CD) patients with endoscopic remission are not well defined. The aim of this study was to determine if histologic activity in patients with endoscopic remission is associated with future risk of endoscopic and/or radiologic postoperative recurrence (POR). METHODS: In this multicenter retrospective cohort study, adult patients with CD who underwent ICR between 2009 and 2020 with endoscopic biopsies of ileal mucosa from Rutgeerts i0 on index colonoscopy were included. The composite rate of endoscopic (Rutgeerts score ≥i2b) and radiologic (active inflammation on imaging) recurrence was compared in patients with and without histologic activity using a Kaplan-Meier survival analysis. A multivariable Cox proportional hazard regression model including clinically relevant risk factors of POR, postoperative biologic prophylaxis, and histology activity was designed. RESULTS: A total of 113 patients with i0 disease on index colonoscopy after ICR were included. Of these, 42% had histologic activity. Time to POR was significantly earlier in the histologically active versus normal group ( P = 0.04). After adjusting for clinical risk factors of POR, histologic activity (HR 2.37, 95% CI 1.17-4.79; P = 0.02) and active smoking (HR 2.54, 95% CI 1.02-6.33; P = 0.05) were independently associated with subsequent composite POR risk. DISCUSSION: In patients with postoperative CD, histologic activity despite complete endoscopic remission is associated with composite, endoscopic, and radiographic recurrence. Further understanding of the role of histologic activity in patients with Rutgeerts i0 disease may provide a novel target to reduce disease recurrence in this population.

Sexual Health in Sexual and Gender Minority Patients with Inflammatory Bowel Disease.

BACKGROUND: In recent years, legislation targeting the sexual and gender minority (SGM) community has been passed at an increasingly alarming rate, affecting access to safe and effective gender-affirming care and forcing many SGM patients, including those with inflammatory bowel disease (IBD), to withhold their identities and health concerns. Additionally, SGM patients with IBD may have unique health considerations that have not yet been well-studied OBJECTIVE: This article aims to explore the intersection of IBD and sexual health in patients who identify as SGM and to identify limitations for gastroenterologists in caring for SGM patients. The article also aims to provide suggestions for improvement in SGM-competent care within gastroenterology METHODS: A thorough literature review was conducted regarding sexual health and the SGM community with IBD. This included a review of surgical considerations in SGM patients, sexually transmitted infections (STIs) and prevention, and sexual dysfunction RESULTS: Overall, little is known about the impact of IBD on patients who identify as sexual and gender minorities. Surgery, medications, and STIs continue to be a concern in the SGM community with IBD and these areas represent opportunities to improve SGM-competent IBD care. Additionally, implementation of an SGM-focused curriculum is urgently needed in medical education to improve provider knowledge and care for this unique group of patients CONCLUSIONS: Patients with IBD who identify as SGM experience challenges that are not well described in prior literature. More research is needed and is actively being pursued to guide provider awareness and improve sexual health for this patient population.

Upadacitinib as Rescue Therapy for the Treatment of Acute Severe Colitis in an Acute Care Setting.

BACKGROUND: Inflammatory bowel disease is a chronic, relapsing, and remitting inflammatory disorder that despite advances in medical therapy often requires hospitalization for treatment of acute flares with intravenous corticosteroids. Many patients will not respond to corticosteroids and require infliximab or cyclosporine as rescue therapy. If medical therapy fails, definitive surgical management is required. Recently, Janus Kinase inhibitors, including upadacitinib, have been proposed as an alternative rescue therapy. AIMS: We hypothesized that upadacitinib may be effective in treating acute severe colitis. METHODS: A retrospective review of 12 inflammatory bowel disease patients admitted for acute severe colitis who received upadacitinib induction therapy was performed. The rates of surgery, repeat or prolonged steroid use, and re-admission within 90 days of index hospitalization were measured. The need for re-induction with upadacitinib, change in medical therapy, rates of clinical remission, change in 6-point partial Mayo score, and laboratory markers of inflammation were measured as secondary outcomes. RESULTS: Five patients met the primary composite endpoint including four patients requiring surgery and one additional patient being unable to withdraw steroids within 90 days of hospital discharge. One patient required re-induction with upadacitinib within 90 days and no patients required change in medical therapy within 90 days. Most patients who did not undergo surgery were in clinical remission within 90 days and showed clinical improvement with decreased 6-point partial Mayo scores. CONCLUSION: Upadacitinib may be effective salvage therapy for acute severe colitis, but larger controlled trials are required to validate these results.

Comparative Safety of Biologic Agents in Patients With Inflammatory Bowel Disease With Active or Recent Malignancy: A Multi-Center Cohort Study.

BACKGROUND & AIMS: Safety of biologic agents is a key consideration in patients with inflammatory bowel disease (IBD) and active or recent cancer. We compared the safety of tumor necrosis factor (TNF)-α antagonists vs non-TNF biologics in patients with IBD with active or recent cancer. METHODS: We conducted a multicenter retrospective cohort study of patients with IBD and either active cancer (cohort A) or recent prior cancer (within ≤5 years; cohort B) who were treated with TNFα antagonists or non-TNF biologics after their cancer diagnosis. Primary outcomes were progression-free survival (cohort A) or recurrence-free survival (cohort B). Safety was compared using inverse probability of treatment weighting with propensity scores. RESULTS: In cohort A, of 125 patients (483.8 person-years of follow-up evaluation) with active cancer (age, 54 ± 15 y, 75% solid-organ malignancy), 10 of 55 (incidence rate [IR] per 100 py, 4.4) and 9 of 40 (IR, 10.4) patients treated with TNFα antagonists and non-TNF biologics had cancer progression, respectively. There was no difference in the risk of progression-free survival between TNFα antagonists vs non-TNF biologics (hazard ratio, 0.76; 95% CI, 0.25-2.30). In cohort B, of 170 patients (513 person-years of follow-up evaluation) with recent prior cancer (age, 53 ± 15 y, 84% solid-organ malignancy; duration of remission, 19 ± 19 mo), 8 of 78 (IR, 3.4) and 5 of 66 (IR 3.7) patients treated with TNFα antagonists and non-TNF biologics had cancer recurrence, respectively. The risk of recurrence-free survival was similar between both groups (hazard ratio, 0.94; 95% CI, 0.24-3.77). CONCLUSIONS: In patients with IBD with active or recent cancer, TNFα antagonists and non-TNF biologics have comparable safety. The choice of biologic should be dictated by IBD disease severity in collaboration with an oncologist.

Surveillance for Colorectal Neoplasia in Inflammatory Bowel Disease: When to Stop.

Patients with chronic ulcerative and Crohn's colitis are at increased risk for colorectal neoplasia(CRN [dysplasia and cancer]) compared to the general population. Risk factors for CRN include extent of colitis, cumulative inflammatory burden, family history of colorectal cancer, and primary sclerosing cholangitis. Best practices to prevent CRN include control of colonic inflammation, high quality surveillance colonoscopy with or without enhanced imaging techniques, resection of visible dysplasia if possible, and colectomy in patients with unresectable dysplasia, invisible multifocal low grade dysplasia, or invisible high grade dysplasia. Cessation of dysplasia surveillance is individualized and should involve shared decision making based on factors including but not limited to chronologic age, frailty, co-morbid conditions, life expectancy, results of prior surveillance exams, and risk factors for CRN.

Anastomotic Configuration and Temporary Diverting Ileostomy Do Not Increase Risk of Anastomotic Stricture in Postoperative Crohn's Disease.

INTRODUCTION: Surgical management of Crohn's disease (CD) is common. Postoperative complications include anastomotic stricturing (AS). The natural history and risk factors for AS have not been elucidated. METHODS: A retrospective cohort study of patients with CD who underwent ileocolonic resection (ICR) with ≥1 postoperative ileocolonoscopy between 2009 and 2020. Postoperative ileocolonoscopies with corresponding cross-sectional imaging were evaluated for evidence of AS without neoterminal ileal extension. Severity of AS and endoscopic intervention at time of detection were collected. Primary outcome was development of AS. Secondary outcome was time to AS detection. RESULTS: A total of 602 adult patients with CD underwent ICR with postoperative ileocolonoscopy. Of these, 426 had primary anastomosis, and 136 had temporary diversion at time of ICR. Anastomotic configuration consisted of 308 side-to-side, 148 end-to-side, and 136 end-to-end. One hundred ten (18.3%) patients developed AS with median time of 3.2 years to AS detection. AS severity at time of detection was associated with need for repeat surgical resection for AS. On multivariable Cox proportional hazard regression, anastomotic configuration and temporary diversion were not associated with risk of or time to AS. Preoperative stricturing disease was associated with decreased time to AS (adjusted hazard ratio 1.8; P = 0.049). Endoscopic ileal recurrence before AS was not associated with subsequent AS detection. DISCUSSION: AS is a relatively common postoperative CD complication. Patients with previous stricturing disease behavior are at increased risk of AS. Anastomotic configuration, temporary diversion, and ileal CD recurrence do not increase risk of AS. Early detection and intervention for AS may help prevent progression to repeat ICR.

Change in Biologic Class Promotes Endoscopic Remission Following Endoscopic Postoperative Crohn's Disease Recurrence.

GOALS: Assess the outcomes of various therapeutic regimens to treat initial endoscopic postoperative recurrence despite biologic prophylaxis. BACKGROUND: Postoperative biologic prophylaxis reduces postoperative Crohn's disease (CD) recurrence rates. Optimal treatment strategies for endoscopic recurrence have not been elucidated. STUDY: Retrospective cohort study of adult CD patients who underwent ileocolonic resection between 2009 and 2020. Patients with endoscopic postoperative recurrence despite prophylactic biologic therapy and ≥1 subsequent colonoscopy were included. Treatment changes after recurrence were categorized as (1) therapy optimization or continuation or (2) new biologic class. The primary outcome was composite endoscopic or surgical recurrence at the time of or prior to subsequent follow-up colonoscopy. RESULTS: Eighty-one CD patients with endoscopic recurrence (54.3% i2b, 22.2% i3, and 23.5% i4) despite biologic prophylaxis (86.4% anti-tumor necrosis factor, 8.6% vedolizumab, 4.9% ustekinumab) were included. Most patients received therapy optimization or continuation (76.3%, n=61) following recurrence compared to being started on a new biologic class. Sixty patients (N=48 therapy optimization; N=12 new biologic class) experienced composite recurrence (78.3% endoscopic, 21.7% surgical). On multivariable modeling, initiation of a new biologic class was associated with reduced risk for composite recurrence compared to therapy optimization or continuation (aOR: 0.26; P=0.04). Additionally, initiation of a new biologic class was associated with endoscopic improvement when adjusting for endoscopic severity at the time of recurrence (aOR: 3.4; P=0.05). On sensitivity analysis, a new biologic class was associated or trended with improved rates of endoscopic healing and composite recurrence when directly compared to therapy optimization or continuation. CONCLUSION: In patients with CD who experience endoscopic recurrence despite biologic prophylaxis, changing the mechanism of biologic action may promote endoscopic improvement.

Suboptimal Guideline Adherence and Biomarker Underutilization in Monitoring of Post-operative Crohn's Disease.

BACKGROUND: Crohn's disease recurrence after ileocecal resection is common. Guidelines suggest colonoscopy within 6-12 months of surgery to assess for post-operative recurrence, but use of adjunctive monitoring is not protocolized. We aimed to describe the state of monitoring in post-operative Crohn's. METHODS: We conducted a retrospective study of patients with Crohn's after ileocolic resection with ≥ 1-year follow-up. Patients were stratified into high and low risk based on guidelines. Post-operative biomarker (C-reactive protein, fecal calprotectin), cross-sectional imaging, and colonoscopy use were assessed. Biomarker, radiographic, and endoscopic post-operative recurrence were defined as elevated CRP/calprotectin, active inflammation on imaging, and Rutgeerts ≥ i2b, respectively. Data were stratified by surgery year to assess changes in practice patterns over time. P-values were calculated using Wilcoxon test and Fisher exact test. RESULTS: Of 901 patients, 53% were female and 78% high risk. Median follow-up time was 60 m for LR and 50 m for high risk. Postoperatively, 18% low and 38% high risk had CRPs, 5% low and 10% high risk had calprotectins, and half of low and high risk had cross-sectional imaging. 29% low and 38% high risk had colonoscopy by 1 year. Compared to pre-2015, time to first radiography (584 days vs. 398 days) and colonoscopy (421 days vs. 296 days) were significantly shorter for high-risk post-2015 (P < 0.001). Probability of colonoscopy within 1 year increased over time (0.48, 2011 vs. 0.92, 2019). CONCLUSION: Post-operative colonoscopy completion by 1 year is low. The use of CRP and imaging are common, whereas calprotectin is infrequently utilized. Practice patterns are shifting toward earlier monitoring.

Gastrointestinal Infection and Risk of Microscopic Colitis: A Nationwide Case-Control Study in Sweden.

BACKGROUND AND AIMS: Gastrointestinal infections have been linked to changes in the composition and function of gut microbiome and development of inflammatory bowel diseases. We therefore sought to examine the relationship between gastroenteritis and risk of microscopic colitis (MC). METHODS: We conducted a case-control study of all adult patients with MC diagnosed between 1990 and 2016 in Sweden matched to up to 5 general population controls according to age, sex, calendar year, and county. Cases of MC were identified using Systematized Nomenclature of Medicine codes from the ESPRESSO (Epidemiology Strengthened by histoPathology Reports in Sweden) study, a cohort of gastrointestinal pathology reports from all 28 pathology centers in Sweden. We used logistic regression modeling to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs). RESULTS: Through December of 2016, we matched 13,468 MC cases to 64,479 controls. The prevalence of previous diagnosed gastrointestinal infection was 7.5% among patients with MC, which was significantly higher than in controls (3.0%, Pcomparison < .001). After adjustment, gastroenteritis was associated with an increased risk of MC (aOR 2.63; 95% CI 2.42-2.85). Among specific pathogens, Clostridioides difficile (aOR 4.39; 95% CI 3.42-5.63), Norovirus (aOR 2.87; 95% CI 1.66-4.87), and Escherichia species (aOR 3.82; 95% CI 1.22-11.58), but not Salmonella species, were associated with an increased risk of MC. The association between gastrointestinal infections and risk of MC was stronger for collagenous subtype (aOR 3.23; 95% CI 2.81-3.70) as compared with lymphocytic colitis (aOR 2.51; 95% CI 2.28-2.76; Pheterogeneity = .005). The associations remained significant after adjustment for immune-mediated conditions and polypharmacy and when compared with unaffected siblings. CONCLUSION: In a nationwide study, we found that gastrointestinal infection, particularly Clostridioides difficile, is associated with an increased risk of subsequent MC. This study was approved by the Regional Ethics Committee, Stockholm, Sweden (Protocol no. 2014/1287-31/4).