Faculty Bibliography

Introduction: Ileocecal resection (ICR) often leads to remission of Crohn's Disease (CD), but relapse is common. Guidelines suggest postoperative biologic prophylaxis in high-risk patients and colonoscopy within 6-12 months of surgery to assess for post-operative recurrence (POR). Guidance on adjunctive disease monitoring modalities such as biomarkers and cross-sectional imaging is lacking. We aimed to describe the real-world surveillance approach for CD patients after ICR in relation to evidence-based guidelines.
Method(s): This was a dual center retrospective study of CD patients who underwent ICR with >=1 year of follow-up. We grouped patients into high- (HR) and low-risk (LR) for POR per guidelines and assessed the use of biomarkers, imaging, and colonoscopy postoperatively. Approaches and recurrence rates in patients who received resection prior to or after 2015, accounting for changing practices with guidelines, were compared. Biomarker, radiographic, and endoscopic POR were defined as high CRP/fecal calprotectin (FC), active inflammation on CT/MRE, and modified Rutgeerts >=i2b, respectively. P-values were calculated using Wilcoxon and Chi squared tests.
Result(s): Of 1026 CD patients who underwent ICR, 798 were HR. For LR patients, median time to first CRP was 244 days (d), FC was 267d, imaging was 579d, and colonoscopy was 392d. For HR patients, median time to first CRP was 183d, FC was 241d, imaging was 460d, and colonoscopy was 352d. 72% of HR patients had at least 1 modality within 1 year compared to 59% of LR. Compared to pre-2015, patients who underwent an ICR in 2015 or later had significantly earlier imaging (543d vs. 379d, p< 0.001) and colonoscopy (404d vs. 292d, p< 0.001). There was no difference in time to first CRP or FC. Timing of ICR was significantly associated with postoperative biologic use and the detection of POR by all methods (p< 0.001).
Conclusion(s): 30% of HR CD patients did not undergo any monitoring within the first year after ICR. Evolving practice patterns suggest earlier disease monitoring with imaging and colonoscopy in more recent years whereas utilization of biomarkers was not changed. These data suggest that while guidelines have changed practice, allowing for the earlier identification of POR and initiation of therapy, many patients remain under-monitored. As earlier monitoring may improve long-term clinical outcomes, additional studies are required to further guide optimal surveillance intervals and use of biomarkers

Introduction: Infliximab (IFX) has been efficacious in reducing colectomy rates among patients with moderate-to severe ulcerative colitis, but predictors of colectomy within 30 days of IFX among patients with acute severe ulcerative colitis (ASUC) are less established.
Method(s): We performed a single-center retrospective analysis of patients who received at least one dose of IFX while admitted between 2011-2022. We assessed demographic, clinical and laboratory predictors of colectomy within 30 days of first IFX dose. Multivariable and time-to-event analysis using Kaplan-Meier with log-rank statistics were used to assess risk factors for colectomy within 30 days.
Result(s): A majority of the 172 patients hospitalized with ASUC who received IFX received 10 mg/kg (87.79%). Overall, 22/172 patients (12.79%) underwent colectomy within 30 days of first IFX dose. On univariable analysis, age, sex, race, ethnicity, BMI and smoking status were not associated with risk of colectomy. Higher initial CRP was significantly associated with 30-day risk of colectomy (106.17 vs. 65.10 mg/dL among patients who did not undergo colectomy; p< 0.01), as was a decrease of CRP <=50% prior to discharge (p< 0.01). Lower initial albumin [< 3 (36.36%), 3.0-3.5 (40.91%), >3.5 g/dL (22.73%)] was associated with our primary outcome (p=0.046), as was a higher number of bowel movements in a 24-hour period prior to discharge (5.6 vs. 3.9 among patients who did not undergo colectomy; p=0.0256). On multivariable analysis, higher initial CRP (aOR 1.01, 95% CI 1.00 - 1.02), <=50% change in CRP after first dose of IFX (aOR 9.00, 95% CI 2.43 - 33.29) and higher number of bowel movements in a 24-hour period prior to discharge (aOR 1.24, 95% CI 1.01- 1.52) remained significantly associated with risk of colectomy when adjusting for relevant covariables (Table). On Kaplan-Meier analysis, initial CRP >100 mg/ dL, albumin < 3 g/dL and change in CRP <=50% prior to discharge were significantly associated with decreased time to colectomy (Figure).
Conclusion(s): Among patients with ASUC, higher CRP, decrease of CRP <=50% and higher number of bowel movements prior to discharge were associated with increased risk of colectomy within 30-days of receiving IFX. Initial CRP >100 mg/dL, albumin < 3 g/dL and decrease of <=50% in CRP prior to discharge were associated with decreased time to colectomy. These results can identify patients at highest risk and impact clinical decision-making regarding need for and timing of colectomy in patients with ASUC receiving IFX. (Table Presented)

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 disease^1-7. Non-classical lymphoid cells, broadly referred to as intraepithelial lymphocytes (IELs), intercalate the intestinal epithelium^8,9. 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.

BACKGROUND & AIMS/OBJECTIVE:Postoperative Crohn's disease (CD) surveillance relies on endoscopic monitoring. The role of cross-sectional imaging is less clear. We evaluated the concordance of cross-sectional enterography with endoscopic recurrence and the predictive ability of radiography for future CD postoperative recurrence. METHODS:We performed a multi-institution retrospective cohort study of postoperative adult patients with CD who underwent ileocolonoscopy and cross-sectional enterography within 90 days of each other following ileocecal resection. Imaging studies were interpreted by blinded, expert CD radiologists. Patients were categorized by presence of endoscopic postoperative recurrence (E+) (modified Rutgeerts' score ≥i2b) or radiographic disease activity (R+) and grouped by concordance status. RESULTS:A total of 216 patients with CD with paired ileocolonoscopy and imaging were included. A majority (54.2%) exhibited concordance (34.7% E+/R+; 19.4% E-/R-) between studies. The plurality (41.7%; n = 90) were E-/R+ discordant. Imaging was highly sensitive (89.3%), with low specificity (31.8%), in detecting endoscopic postoperative recurrence. Intestinal wall thickening, luminal narrowing, mural hyper-enhancement, and length of disease on imaging were associated with endoscopic recurrence (all P < .01). Radiographic disease severity was associated with increasing Rutgeerts' score (P < .001). E-/R+ patients experienced more rapid subsequent endoscopic recurrence (hazard ratio, 4.16; P = .033) and increased rates of subsequent endoscopic (43.8% vs 22.7%) and surgical recurrence (20% vs 9.5%) than E-/R- patients (median follow-up, 4.5 years). CONCLUSIONS:Cross-sectional imaging is highly sensitive, but poorly specific, in detecting endoscopic disease activity and postoperative recurrence. Advanced radiographic disease correlates with endoscopic severity. Patients with radiographic activity in the absence of endoscopic recurrence may be at increased risk for future recurrence, and closer monitoring should be considered.

Inflammatory bowel diseases (IBD), including Crohn disease and ulcerative colitis, are chronic inflammatory conditions of the gastrointestinal tract. Individuals with IBD are at increased risk for several malignancies originating in the intestine, such as colorectal cancer, small bowel adenocarcinoma, intestinal lymphoma, and anal cancer. There are also several extraintestinal malignancies associated with IBD and IBD therapies, including cholangiocarcinoma, skin cancer, hematologic malignancies, genitourinary cancer, cervical cancer, and prostate cancer. The authors summarize the risk of cancer in patients with IBD, diagnosis and management of colorectal neoplasia in IBD, and management of patients with IBD and active or recent cancer.

BACKGROUND:Colorectal strictures have been considered independent risk factors for neoplasia in patients with inflammatory bowel disease (IBD). We examined the association between colorectal stricture and subsequent risk of colorectal neoplasia (CRN) in patients with IBD colitis undergoing colonoscopic surveillance. METHODS:We conducted a retrospective cohort analysis of patients with IBD colitis enrolled in colonoscopic surveillance for CRN at an academic medical center between 2005 and 2017. Inclusion criteria were IBD involving the colon for ≥8 years (or any duration with primary sclerosing cholangitis [PSC]) undergoing surveillance. Exclusion criteria were advanced CRN (ACRN; colorectal cancer [CRC] or high-grade dysplasia [HGD]) prior to or at enrollment, prior colectomy, or limited (<30%) disease extent or proctitis. Multivariable logistic and Cox regression analysis estimated the association between colorectal stricture on the index colonoscopy and ACRN, CRN (indefinite dysplasia, low-grade dysplasia, HGD, CRC), or colectomy. RESULTS:Among 789 patients with IBD undergoing CRC surveillance, 72 (9%; 70 with Crohn's colitis) had a colorectal stricture on index colonoscopy. There was no significant difference in the frequency of ACRN or requirement for colectomy between patients with vs without a colorectal stricture (P > .05). Colorectal stricture was not associated with subsequent ACRN (adjusted odds ratio [aOR], 1.41; 95% CI, 0.49-4.07), CRN (aOR, 1.15; 95% CI, 0.51-2.58), or colectomy (aOR, 1.10; 95% CI, 0.65-1.84). CONCLUSIONS:In this analysis of patients with IBD colitis undergoing CRN surveillance, the presence of a colorectal stricture was not independently associated with risk of ACRN or colectomy. Multicenter, prospective studies are needed to confirm these findings, particularly in patients with ulcerative colitis-associated colorectal stricture.

BACKGROUND & AIMS/OBJECTIVE:Disability in patients with medically refractory ulcerative colitis (UC) after total proctocolectomy (TPC) with ileal pouch anal anastomosis (IPAA) is not well understood. The aim of this study was to compare disability in patients with IPAA vs medically managed UC, and identify predictors of disability. METHODS:This was a multicenter cross-sectional study performed at 5 academic institutions in New York City. Patients with medically or surgically treated UC were recruited. Clinical and socioeconomic data were collected, and the Inflammatory Bowel Disease Disability Index (IBD-DI) was administered to eligible patients. Predictors of moderate-severe disability (IBD-DI ≥35) were assessed in univariable and multivariable models. RESULTS:A total of 94 patients with IPAA and 128 patients with medically managed UC completed the IBD-DI. Among patients with IPAA and UC, 35 (37.2%) and 30 (23.4%) had moderate-severe disability, respectively. Patients with IPAA had significantly greater IBD-DI scores compared with patients with medically managed UC (29.8 vs 17.9; P < .001). When stratified by disease activity, patients with active IPAA disease had significantly greater median IBD-DI scores compared with patients with active UC (44.2 vs 30.4; P = .01), and patients with inactive IPAA disease had significantly greater median IBD-DI scores compared with patients with inactive UC (23.1 vs 12.5; P < .001). Moderate-severe disability in patients with IPAA was associated with female sex, active disease, and public insurance. CONCLUSIONS:Patients with IPAA have higher disability scores than patients with UC, even after adjustment for disease activity. Female sex and public insurance are predictive of significant disability in patients with IPAA.

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.