P212 Assessment of Crohn’s disease activity using global MaRIA score in patients with ileal and ileocolonic disease

Background Magnetic resonance index of activity (MaRIA) is composed of features independently associated with endoscopic disease activity and is surrogate marker of disease activity. The aim of this study was to evaluate correlation of global MaRIA (gMaRIA) with clinical and biochemical disease activity indices and diagnostic accuracy for active disease in patients with terminal ileum disease and ileocolonic disease. Methods This is a cross-sectional study which included 251 patients with diagnosed CD. Global MaRIA (gMaRIA) index was calculated on 6 bowel segments (the distal ileum, ascending, transverse, descending, sigmoid colon and rectum) using following parameters: bowel wall thickness, ulcers, edema and relative contrast enhancement. Disease activity was defined as combination of clinical and biochemical disease activity (CRP>5 or HBI≥5). Disease extension was classified using Montreal classification (L1 ileum, L2 colon, L3 ileum and colon). Results This study included 251 CD patients [age 35 (25–47), 55.3% males, BMI 21.8 (18–25) kg/m2, median disease duration 7 (2–15) years]. Ileal disease (L1) was present in 84 (33.5%) and ileocolonic disease (L3) in 151 (60.1%) patients. Correlation of gMARIA with biochemical indices of disease activity (CRP) was r=0.48, p<0.001 and with HBI r=0.33, p<0.001. Diagnostic accuracy of gMARIA in defining active disease in patients with L1 disease was considerably high [AUC 0.83 (95%CI 0.72–0.91)]. On the other hand, diagnostic accuracy in defining active disease in patients with L3 disease was good [AUC 0.71 (95%CI 0.62–0.79)], which is lower compared to L1 disease. In surgically naïve patients diagnostic accuracy of L1 disease was [AUC 0.88 (95%CI 0.72–0.96)], and for L3 disease [AUC 0.78 (95%CI 0.64–0.89)]. Conclusion Global MaRIA index showed higher diagnostic accuracy in detecting clinically and biochemically active disease in terminal ileum compared to ileocolic disease. These results emphasize the important role of magnetic resonance enterography in monitoring disease activity in patients with isolated ileal disease. Global MaRIA score correlates better with biochemical disease activity compared to clinical disease activity, which points out to the significance of biochemical remission.

Association of Serum Immunoglobulins Levels With Specific Disease Phenotypes of Crohn's Disease: A Multicenter Analysis in China

Background and Aim: Serum immunoglobulins were reported to be associated with clinical characteristics of inflammatory bowel disease. However, whether a difference exists in the serum immunoglobulins levels in patients with Crohn's disease (CD) with different disease location and behavior phenotypes remains unclear. Therefore, this study aimed to explore the associations of serum immunoglobulins levels with specific CD phenotypes.Methods: Patients with CD having recorded serum immunoglobulins levels were recruited through multicenter collaborative efforts. The associations between serum immunoglobulins levels and distinct phenotypes of CD were evaluated using multiple logistic regression models.Results: A total of 608 patients with CD were included in the study. Elevated (above the upper limit of normal) serum immunoglobulin G (IgG), IgA, IgM, and IgG4 were identified in 24.5, 17.4, 2.1, and 8.2% of patients, respectively. Elevated serum IgG4 levels negatively correlated with complicated disease behavior [odds ratio (OR) 0.49, 95% confidence interval (CI) 0.26–0.92]. Elevated serum IgG was linked to isolated ileal disease with an OR of 0.37 (95% CI 0.23–0.61). The ORs of isolated ileal disease progressively reduced across increasing quartiles of IgG (P for trend < 0.001). The adjusted ORs of isolated ileal disease for increasing quartiles of IgM were 1.82 (1.07–3.1), 1.92 (1.14–3.24), 1.17 (0.69–1.98), and 1 (P for trend = 0.008). Besides, serum IgA and IgG levels significantly correlated with several disease activity indices.Conclusions: These results suggested that certain serum immunoglobulins were associated with specific disease phenotypes of CD. Further investigations to account for the associations are warranted.

Early Combined Immunosuppression May Be More Effective for Reducing Complications in Isolated Colonic- vs Ileal-Dominant Crohn Disease

Background We assessed whether differential efficacy of early combined immunosuppression (ECI) in comparison with conventional management (CM) is present in patients with Crohn disease (CD) according to disease location. Methods In this posthoc analysis of the Randomized Evaluation of an Algorithm for Crohn’s Treatment trial, the effect of ECI vs CM modified by disease location (isolated-colonic vs ileal-dominant) in terms of time to first complication (hospitalization, surgery, or disease-related complications—presence of a new abscess, fistula, or stricture; serious worsening of disease activity; extraintestinal manifestations) was analyzed using a marginal Cox proportional hazard model to account for cluster randomization. Factors adjusted included practice size, country, and other covariates selected in a backward logistic regression analysis with the first composition as outcome and P < 0.10. Results Of the 1969 patients with CD, 435 had isolated colonic CD (ECI n = 257, CM n = 178) and 1534 had ileal CD (ECI n = 817, CM n = 717). Over 24 months there was a significant differential impact for ECI vs CM for reducing the risk of a CD-related complication between patients with colonic CD and ileal CD (colonic CD hazard ratio [HR] = 0.51; 95% CI, 0.30-0.85 vs ileal CD HR = 0.79; 95% CI, 0.57-1.10; P = 0.033). No difference was identified between ECI vs CM for reducing the risk of surgery (colonic HR = 0.52 vs ileal HR = 0.74; P = 0.468) or hospitalization (colonic HR = 0.77 vs ileal HR = 0.83; P = 0.806). Conclusions In this posthoc analysis of the Randomized Evaluation of an Algorithm for Crohn’s Treatment trial, symptom-based ECI was associated with greater efficacy for reducing the risk of CD-related complications in patients with colonic disease location relative to ileal disease location.

P507 Ustekinumab: Medium-term outcomes from a UK multicentre real-world cohort

Background Ustekinumab is effective at inducing and maintaining remission of Crohn’s disease (CD) in clinical trials. However real-world practice may vary regarding use of concomitant immunomodulator (IM), dosing schedule and patient selection. We present the largest UK real-world, multi-centre study of effectiveness. Methods The cohort comprised adult patients initiated on ustekinumab for CD from October 2016–18 at 3 tertiary London centres. Clinical endpoints were (i) remission (Harvey Bradshaw Index (HBI) ≤4) (ii) response, (reduction in HBI of ≥3 or sustained HBI≤4 points) at 3, 6 and 12 months. Biological endpoints were remission and response (CRP <5mg/l in patients with a baseline CRP>5mg/l, and 50% reduction in CRP, respectively). Results 211 patients were included (Table 1), of whom 207 (98%) were biologic exposed and 59 (28%) had failed 3 biologics. All patients received i.v. induction and 203 (96%) received a s.c. dose at week 8. At 6 and 12 months, 133 (74.8%) and 109 (73.6%) patients, respectively, were on 8 weekly dosing. Dosing schedule did not impact clinical and biological outcome at 6 and 12 months. Discontinuation occurred in 4 (1.9%), 20 (9.5%) and 50 (23.7%) patients by 3, 6 and 12 months respectively. Reasons for stopping included: drug reactions (4(1.9%)), partial response (4 (1.9%)), loss of response (10 (4.7%)) and primary non-response. (24 (11.4%)). Clinical and biological outcomes at 3, 6 and 12 months are shown in Figure 1. Adverse events occurred in 27 (12.8%) patients. IM were prescribed in 49 (23%) at baseline and continued in 46 (21.8%), 36 (17.1%), 27 (12.8%) at 3, 6 and12 months respectively. There was no significant difference in median persistence (months) on ustekinumab between patients who were on an IM at baseline vs. those not (15.2 (95% CI 0–32.2) vs. 23.3 (17.3–29.4) months, p = 0.4). Likewise, there was no significant difference in clinical or biological outcome between patients with colonic vs. ileocolonic or ileal disease. Finally, there was no significant difference in median persistence on ustekinumab between patients with and without a history of perianal disease (19.5 (95% CI 9.2–29.8) vs. 22.9 (18.6–27.2) months, p = 0.8). Conclusion Ustekinumab is effective in a real-world cohort. In keeping with trial data, we did not find evidence of improved outcomes with the use of a concomitant IM, nor differential outcomes when considering perianal and isolated colonic disease.

Phenotypic Variation in Paediatric Inflammatory Bowel Disease by Age: A Multicentre Prospective Inception Cohort Study of the Canadian Children IBD Network

Background and Aims Incidence of paediatric inflammatory bowel disease [IBD] in Canada is among the highest worldwide, and age of onset may be decreasing. In a multicentre nationwide inception cohort study, we examined variation in phenotype of IBD throughout the paediatric age spectrum. Methods Children aged ≥2 years [y] and <17y [A1 age at diagnosis], with new onset IBD, were systematically evaluated at sites of the Canadian Children IBD Network. Prospectively recorded phenotypic data were compared between age groups. Results Among 1092 children (70% Caucasian; 64% Crohn’s disease [CD], 36% ulcerative colitis/inflammatory bowel disease unclassified [UC/IBD-U]; median age 13 y, interquartile range [IQR] 11–15 y), 210 [19%] were diagnosed before the age of age 10 y [Paris A1a] and 43 [4%] before age 6 y (very-early-onset [VEO-IBD]). CD was less common in younger children [42%, 56%, 66%, respectively, of VEO-IBD, A1a; A1b]. Colon-only IBD [UC/IBDU or CD-colon] was present in 81% of VEO-IBD and 65% of A1a; ileal disease increased progressively, reaching plateau at age 10 y. CD location was ileocolonic [L3] in 53% overall. Ileitis [L1] increased with age [6% of VEO-IBD; 13% of A1a; 21% of A1b], as did stricturing/penetrating CD [4% of A1a; 11% of A1b]. At all ages UC was extensive [E3/E4] in >85%, and disease activity moderate to severe according to Physician’s Global Assessment [PGA] and weighted Paediatric Crohn’s Disease Activity Index/Paediatric Ulcerative Colitis Activity Index [wPCDAI/PUCAI] in >70%. Heights were modestly reduced in CD [mean height z score -0.30 ± 1.23], but normal in UC/IBD-U. Conclusions Paris classification of age at diagnosis is supported by age-related increases in ileal disease until age 10 years. Other phenotypic features, including severity, are similar across all ages. Linear growth is less impaired in CD than in historical cohorts, reflecting earlier diagnosis.

Colonic Epithelial miR-31 Associates with the Development of Crohn’s Phenotypes

Crohn’s disease (CD) is highly heterogeneous, due in large part to variability in cellular processes that underlie the natural history of CD, thereby confounding effective therapy. There is a critical need to advance understanding of the cellular mechanisms that drive CD heterogeneity. In this study, small RNA-sequencing and microRNA profiling in the colon revealed two distinct molecular subtypes, each with different clinical associations, in both adult and treatment-naïve pediatric CD patients. Notably, we found that microRNA-31 (miR-31) expression by itself can stratify patients into these two subtypes. Through detailed analysis of several colonic mucosa cell types from adult patients, we found that differential levels of miR-31 are particularly pronounced in epithelial cells. We generated patient crypt-derived epithelial colonoids and showed that miR-31 expression differences preserved in this ex-vivo system. In adult patients, low colonic miR-31 expression levels at the time of surgery are associated with post-operative recurrence of ileal disease. In pediatric patients, lower miR-31 expression at the time of diagnosis is associated with the future development of fibrostenotic ileal CD requiring surgery. These findings represent an important step forward in designing more effective clinical trials and developing personalized therapies for CD.

Different clinical outcomes in Crohn’s disease patients with esophagogastroduodenal, jejunal, and proximal ileal disease involvement: is L4 truly a single phenotype?

Background: The Montreal classification defines L4 Crohn’s disease (CD) as any disease location proximal to the terminal ileum, which anatomically includes L4-esophagogastroduodenal (EGD), L4-jejunal, and L4-proximal ileal involvement. L4-jejunal disease was established to be associated with poor prognosis. However, the outcome of patients with L4-proximal ileal disease or L4-EGD remains to be clarified. Our study aimed to investigate whether the outcome differs among CD patients with L4-EGD, L4-jejunal, and L4-proximal ileal disease. Methods: In our retrospective cohort study, 483 patients with confirmed CD were included. The primary outcome was intestinal surgery. Demographic features and outcomes were compared among L4-EGD, L4-jejunal, and L4-proximal ileal disease. Results: Thirty-nine (8.1%) patients had isolated L4 disease, whereas 146 patients had L4 as well as concomitant L1, L2, or L3 disease. During a median follow up of 5.8 years, L4 patients were more likely to have intestinal surgeries compared to non-L4 patients (31% versus 16%, p < 0.001). The percentage of L4-jejunal patients who underwent surgery was higher than that of L4-proximal ileal (66% versus 28%, p < 0.001), and both of these subtypes of L4 were at higher risk for intestinal resection compared to L4-EGD patients (66% and 28% versus 9%, respectively, p < 0.001 and p < 0.05). On multi-variable analysis, L4-jejunal (HR 3.08; 95% CI 1.30–7.31) and L4-proximal ileal disease (HR 1.83; 95% CI 1.07–3.15) were independent predictors for intestinal resection. Conclusions: L4 disease had worse prognosis compared to non-L4 disease. Within L4 disease, phenotype of L4-jejunal and L4-proximal ileal disease indicated higher risk for intestinal surgery. It might be justified to further characterize the L4 phenotype of the Montreal classification into three specific subgroups including L4-EGD, L4-jejunal, and L4-proximal ileal disease, similar to the Paris classification of pediatric patients.