Postoperative Recurrence Of Crohn's Disease Research Articles

Long-term risk of delayed postoperative Crohn's disease recurrence in patients with no or mild endoscopic recurrence at first assessment.

Early endoscopic evaluation is recommended for assessment of postoperative recurrence (POR) of Crohn's disease (CD) but no further monitoring recommendations are available. To evaluate the long-term outcome of patients without endoscopic POR at first endoscopic assessment. Retrospective four-centre study including consecutive CD patients with ileocolonic resection (ICR) without endoscopic POR (Rutgeerts score i0-i1) at first endoscopic assessment performed within 18 months from ICR. All patients had a clinical follow-up ≥24 months and at least one further endoscopic assessment. Main outcomes were endoscopic, clinical and surgical POR, need for rescue therapy and "delayed POR" (any need for rescue therapy or clinical or surgical POR) during follow-up. Overall, 183 patients were included (79% with risk factors for POR, 44% without postoperative prophylaxis). Endoscopic POR was observed in 42% of patients. Clinical POR-free survival was 89.4% and 81.5% at 3 and 5 years, and delayed POR-free survival was 76.9% and 63.4% at 5 and 10 years, respectively. In multivariate analysis, postoperative prophylaxis (HR .55; 95% CI .325-.942) and active smoking (HR 1.72; 95%CI 1.003-2.962) were independent risk factors for clinical POR, whereas presence of mild endoscopic lesions at index ileocolonoscopy (i1) was the only risk factor for delayed POR (HR 1.824; 95% CI 1.108-3.002). Long-term risk of POR among patients with no or mild endoscopic lesions at first ileocolonoscopy after surgery is steadily low, being higher among smokers, in the absence of postoperative prophylaxis and when mild endoscopic lesions are observed in the first endoscopic assessment.

How Reliable Is Endoscopic Scoring of Postoperative Recurrence in Crohn Disease?: A Systematic Review and Meta-Analysis

Objective: Guidelines advise to perform endoscopic surveillance following ileocolic resection (ICR) in Crohn disease (CD) for timely diagnosis of recurrence. This study aims to assess the variation in endoscopic recurrence (ER) rates in patients after ICR for CD using the most commonly used classification systems, the Rutgeerts score (RS) and modified Rutgeerts score (mRS) classifications. Methods: A systematic literature search using MEDLINE, Embase, and the Cochrane Library was performed. Randomized controlled trials and cohort studies describing ER < 12 months after an ICR for CD were included. Animal studies, reviews, case reports (<30 included patients), pediatric studies, and letters were excluded. The Newcastle–Ottawa Quality Assessment Scale and Cochrane Collaboration’s tool were used to assess risk of bias. Main outcome was the range of ER rates within 12 months postoperatively, defined as RS ≥ i2 and/or mRS ≥ i2b. A proportional meta-analysis was performed. The final search was performed on January 4, 2022. The study was registered at PROSPERO, CRD42022363208. Results: Seventy-six studies comprising 7751 patients were included. The weighted mean of ER rates in all included studies was 44.0% (95% confidence interval, 43.56–44.43). The overall range was 5.0% to 93.0% [interquartile range (IQR), 29.2–59.0]. The weighted means for RS and mRS were 44.0% and 41.1%, respectively. The variation in ER rates for RS and mRS were 5.0% to 93.0% (IQR, 29.0–59.5) and 19.8% to 62.9% (IQR, 37.3–46.5), respectively. Within studies reporting both RS and mRS, the weighted means for ER were 61.3% and 40.6%, respectively. Conclusions: This study demonstrates a major variation in ER rates after ICR for CD, suggesting a high likelihood of inadequate diagnosis of disease recurrence, with potentially impact on quality of life and health care consumption. Therefore, there is an important need to improve endoscopic scoring of recurrent disease.

Clinical Update on the Prevention and Management of Postoperative Crohn's Disease Recurrence.

Despite advances in therapeutics, a significant portion of patients with Crohn's disease still require surgical management. In this article, we present updates to the natural history, prognostication and postoperative monitoring, and novel therapeutics in the prevention and treatment of postoperative Crohn's disease recurrence. Clinical risk factors have been associated with higher rates of postoperative recurrence (POR), and in recent studies demonstrate an increased cumulative risk with presence of additional risk factors. Additional novel clinical, histologic, and "-omic" risk factors for recurrence have recently been elucidated, including the role of the mesentery on recurrence and perioperative intraabdominal septic complications. High-risk patients benefit most from medical prophylaxis, including anti-TNF with or without immunomodulator therapy to prevent recurrence. New biologics such as vedolizumab and ustekinumab have emerging evidence in the use of prophylaxis, especially with recent REPREVIO trial data. Non-invasive disease monitoring, such as cross-sectional enterography, intestinal ultrasound, and fecal calprotectin, have been validated against ileocolonoscopy. Recent advances in the prediction, prevention, and monitoring algorithms of postoperative Crohn's disease may be leading to a reduction in postoperative recurrence. Ongoing trials will help determine optimal monitoring and management strategies for this at-risk population.

The Management of Postoperative Recurrence in Crohn's Disease.

Crohn's disease (CD) is a chronic inflammatory bowel disease with different phenotypes of presentation, inflammatory, penetrating, or stricturing disease, that significantly impacts patient well-being and quality of life. Despite advances in medical therapy, surgery sometimes represents the only treatment to address complications, such as strictures, fistulas, or abscesses. Minimizing postoperative recurrence (POR) remains a major challenge for both clinicians and patients; consequently, various therapeutic strategies have been developed to prevent or delay POR. The current review outlines an updated overview of POR management. We focused on diagnostic assessment, which included endoscopic examination, biochemical analyses, and cross-sectional imaging techniques, all crucial tools used to accurately diagnose this condition. Additionally, we delved into the associated risk factors contributing to POR development. Furthermore, we examined recent advances in the prophylaxis and treatment of POR in CD.

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

Background & AimsPreoperative risk stratification may help guide prophylactic biologic utilization for the prevention of postoperative Crohn's disease (CD) recurrence; however, there is limited data exploring and validating proposed clinical risk factors. We aimed to explore preoperative clinical risk profiles, quantify individual risk factors, and assess the impact of biologic prophylaxis on postoperative recurrence (POR) risk in a real-world cohort. MethodsIn this multicenter retrospective analysis, patients with CD who underwent ileocecal resection (ICR) from 2009-2020 were identified. High-risk (active smoking, ≥2 prior surgeries, penetrating and/or perianal disease) and low-risk (nonsmokers and age>50 years) features were used to stratify patients. We assessed the risk of endoscopic (Rutgeerts’ score ≥i2b) and surgical recurrence by risk strata and biologic prophylaxis (≤90 days postoperatively) with logistic and time-to-event analyses. ResultsA total of 1404 adult CD patients who underwent ICR were included. Of the high-risk factors, ≥2 ICR (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 versus not (10.2% vs 16.7%; p=0.02), and endoscopic recurrence was lower in those receiving prophylaxis irrespective of risk strata (High-risk: 28.1% vs 37.4%; p=0.03 and Low-risk: 21.1% vs 38.3%; p=0.002). ConclusionsClinical 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.

Anti-TNF Agents and New Biological Agents (Vedolizumab and Ustekinumab) in the Prevention and Treatment of Postoperative Recurrence After Surgery in Crohn's Disease.

Surgery for Crohn's disease (CD) is not curative, as postoperative recurrence (POR) after ileocolonic resection is the rule in the absence of prophylactic treatment. In the present article, we critically review available data on the role of anti-tumour necrosis factor (TNF) agents and new biologics (including vedolizumab and ustekinumab) in the prevention and treatment of POR after surgery in CD. Several studies (summarised in various meta-analyses) have confirmed the efficacy of anti-TNFs in the prevention of POR. We identified 37 studies, including 1863 CD patients, with mean endoscopic POR at 6-12 months of 29%. Only few randomised controlled trials (RCTs) have directly compared thiopurines and anti-TNFs, with controversial results, although the superiority of the latter is supported by several meta-analyses. Infliximab and adalimumab seem equally effective. The combination of anti-TNFs and immunosuppressives should be considered in patients previously exposed to anti-TNFs. Several studies have shown that anti-TNFs remain an effective option to prevent POR also in patients with anti-TNF failure before surgery. In fact, the use of the same anti-TNF before and after surgery might be effective for the prevention of POR. Prophylactic anti-TNF treatment, once started, should be continued long term. Anti-TNFs are also effective for the treatment of established POR. Retreatment with anti-TNFs for POR is a valid strategy even after their preoperative failure. In six studies (including 156 patients) evaluating vedolizumab, mean endoscopic POR at 6-12 months was 41%. The non-randomised comparison of anti-TNFs and vedolizumab has provided controversial results. One placebo-controlled RCT confirmed that vedolizumab is quite effective in preventing POR in CD patients with increased risk of recurrence. Seven studies (including 162 patients) evaluated ustekinumab, with a mean endoscopic POR at 6-12 months of 41%. The comparative efficacy of ustekinumab and anti-TNFs is still unclear. Ustekinumab and vedolizumab seem to be equally effective, although the experience is very limited. In conclusion, to date, anti-TNFs are the most effective agents in preventing and treating POR in CD. Anti-TNFs remain an effective option to prevent POR also in patients with anti-TNF failure before surgery. Vedolizumab seems to be quite effective in the prevention of POR in patients with increased risk of recurrence. Ustekinumab is probably also effective in the postoperative setting, although the comparative efficacy with anti-TNFs or vedolizumab is still unclear.

Ustekinumab is a promising option for the treatment of postoperative recurrence of Crohn's disease.

Postoperative recurrence (POR) following ileocolonic resection is a major concern in patients with Crohn's disease (CD). The role of ustekinumab (UST) in this setting is poorly known. All consecutive CD patients with a baseline colonoscopy at 6-12months from ileocolonic resection showing POR (Rutgeerts score ≥i2) who were treated with UST after the baseline colonoscopy and with an available post-treatment endoscopy, were extracted from the cohort of the Sicilian Network for Inflammatory Bowel Diseases (SN-IBD). The primary outcome was endoscopic success, defined as reduction of at least one point of Rutgeerts score. The secondary outcome was clinical success, assessed at the end of follow-up. Reasons for clinical failure included mild clinical relapse (Harvey-Bradshaw index 5-7), clinically relevant relapse (Harvey-Bradshaw index >7), and need for new resection. Forty-four patients were included (mean follow-up: 17.8±8.4months). The baseline postoperative colonoscopy showed severe POR (Rutgeerts score i3 or i4) in 75.0% of patients. The post-treatment colonoscopy was performed after a mean of 14.5±5.5months following initiation of UST. Endoscopic success was reported in 22 out of 44 (50.0%) patients, of whom 12 (27.3%) achieved a Rutgeerts score i0 or i1. Clinical success at the end of follow-up was reported in 32 out of 44 patients (72.7%); none of the 12 patients with clinical failure had achieved endoscopic success at post-treatment colonoscopy. Ustekinumab could be a promising option for the treatment of POR of CD.

Identification of Potential Genes and Critical Pathways in Postoperative Recurrence of Crohn's Disease by Machine Learning And WGCNA Network Analysis.

Crohn's disease (CD) is a chronic idiopathic inflammatory bowel disease affecting the entire gastrointestinal tract from the mouth to the anus. These patients often experience a period of symptomatic relapse and remission. A 20 - 30% symptomatic recurrence rate is reported in the first year after surgery, with a 10% increase each subsequent year. Thus, surgery is done only to relieve symptoms and not for the complete cure of the disease. The determinants and the genetic factors of this disease recurrence are also not well-defined. Therefore, enhanced diagnostic efficiency and prognostic outcome are critical for confronting CD recurrence. We analysed ileal mucosa samples collected from neo-terminal ileum six months after surgery (M6=121 samples) from Crohn's disease dataset (GSE186582). The primary aim of this study is to identify the potential genes and critical pathways in post-operative recurrence of Crohn's disease. We combined the differential gene expression analysis with Recursive feature elimination (RFE), a machine learning approach to get five critical genes for the postoperative recurrence of Crohn's disease. The features (genes) selected by different methods were validated using five binary classifiers for recurrence and remission samples: Logistic Regression (LR), Decision tree classifier (DT), Support Vector Machine (SVM), Random Forest classifier (RF), and K-nearest neighbor (KNN) with 10-fold cross-validation. We also performed weighted gene co-expression network analysis (WGCNA) to select specific modules and feature genes associated with Crohn's disease postoperative recurrence, smoking, and biological sex. Combined with other biological interpretations, including Gene Ontology (GO) analysis, pathway enrichment, and protein-protein interaction (PPI) network analysis, our current study sheds light on the in-depth research of CD diagnosis and prognosis in postoperative recurrence. PLOD2, ZNF165, BOK, CX3CR1, and ARMCX4, are the important genes identified from the machine learning approach. These genes are reported to be involved in the viral protein interaction with cytokine and cytokine receptors, lysine degradation, and apoptosis. They are also linked with various cellular and molecular functions such as Peptidyl-lysine hydroxylation, Central nervous system maturation, G protein-coupled chemoattractant receptor activity, BCL-2 homology (BH) domain binding, Gliogenesis and negative regulation of mitochondrial depolarization. WGCNA identified a gene co-expression module that was primarily involved in mitochondrial translational elongation, mitochondrial translational termination, mitochondrial translation, mitochondrial respiratory chain complex, mRNA splicing via spliceosome pathways, etc.; Both the analysis result emphasizes that the mitochondrial depolarization pathway is linked with CD recurrence leading to oxidative stress in promoting inflammation in CD patients. These key genes serve as the novel diagnostic biomarker for the postoperative recurrence of Crohn's disease. Thus, among other treatment options present until now, these biomarkers would provide success in both diagnosis and prognosis, aiming for a long-lasting remission to prevent further complications in CD.

P360 Role of intestinal ultrasound scores in the diagnosis of post-operative recurrence in Crohn's disease

Abstract Background Ileocolonoscopy is the gold standard to evaluate post-operative recurrence (POR) in Crohn's disease (CD) patients. Rutgeerts endoscopic score remains the gold standard in the evaluation of post-operative recurrence in CD. Intestinal ultrasound (IUS) is proposed as a non-invasive alternative to ileocolonoscopy for the diagnosis of POR, with a sensitivity of 94% and specificity of 84%. There are several IUS scores that evaluate CD disease activity such as SUS-CD (validated), IBUS-SAS and Simple US Score, which have not yet been studied in the diagnosis of POR. The aim of this study is to assess whether these ultrasound scores correlate with endoscopy in the diagnosis of PR. Methods A retrospective study was performed. Patients with CD who had undergone ileocecal resection, with both an ileocolonoscopy and intestinal ultrasound performed for the detection of POR were included. The time between tests was less than 6 months and there was no therapeutic change between tests. Endoscopic POR was evaluated with Rutgeers score (RS), considering POR RS ≥i2b. In IUS, were used: Simple US Score, SUS-CD and IBUS-SAS. Results Forty-five patients were included (female 48,89%, male 51,11%). The Montreal classification was: L1 n=22 (48,89%), L2=1 (2,22%), L3 n=22 (48,89%), B1 n=3 (6,67%), B2 24 (54,4%) and B3 n=18 (40%). 24 patients (53%) had no endoscopic POR, 6 (6%) had RS i2b and 15 (33.33%) had severe POR. The mean wall thickness measured by IUS was 4.39 mm (SD +/- 1.92) and 26 patients (57.77%) had hyperemia (Limberg score >1). The mean values for IUS scores were: Simple US Score 5.79 (SD +/- 2.81), SUS-CD 2.35 (SD +/- 1.62) and IBUS-SAS 34.04 (SD +/- 24.21). For the Simple US Score an area under the ROC curve (AUC) of 80.65% (95% CI 67.7 - 93.6) was obtained, with a score ≥5.4. The sensitivity (S) was 95.24% and specificity (E) 66.67%. IBUS-SAS presented an AUC of 87% (95% CI 76.98 - 97.02), a result ≥28 granted a S 90.48% and E 70.83%. The SUS-CD index had an AUC of 79% (95% CI 76.98 - 97.92), a result ≥3 presented S 90.48% and E 62.5%. Conclusion In our experience, IUS scores (IBUS-SAS, SUS-CD and Simple US Score) show a high sensitivity in the diagnosis of POR.

Retreatment with anti-tumor necrosis factor therapy in combination with an immunomodulator for recurrence of Crohn's disease after ileocecal resection results in prolonged continuation as compared to anti-tumor necrosis factor monotherapy.

A considerable proportion of Crohn's disease patients that undergo ileocecal resection (ICR) have failed anti-tumor necrosis factor (TNF) therapy preoperatively. This study aimed to assess the effectiveness of retreatment of anti-TNF therapy in patients with postoperative recurrence. A real-world cohort study was performed on Crohn's disease patients who underwent primary ICR after anti-TNF therapy failure, and who were retreated with anti-TNF therapy for postoperative symptomatic Crohn's disease. The primary outcome was treatment failure (the need for (re)introduction of corticosteroids, immunosuppressants, or biologicals or the need for re-resection). Sub-analyses were performed on the nature of preoperative anti-TNF failure (primary non-response, secondary loss of response, intolerance), indication for ICR (refractory, stricturing, penetrating disease), combination therapy with immunomodulators, retreatment with the same anti-TNF agent and preoperative exposure to 1 vs. >1 anti-TNF agents. In total, 66 of 364 patients retreated with anti-TNF therapy following ICR. Cumulative rates of treatment failure at 1 and 2 years were 28% and 47%. Treatment failure rate at 2 years was significantly lower in patients receiving combination therapy as compared to anti-TNF monotherapy (30% vs. 49%, P = 0.02). No difference in treatment failure was found with regards to the nature of preoperative anti-TNF failure (P = 0.76), indication for ICR (P = 0.88) switch of anti-TNF agent (P = 0.55) agent, and preoperative exposure to 1 vs. >1 anti-TNF agents (P = 0.88). Retreatment with anti-TNF therapy for postoperative Crohn's disease recurrence is a valid strategy after preoperative failure. Combination therapy is associated with a lower rate of treatment failure.

S1030 Adalimumab Is Not Superior to Azathioprine in the Prevention of Postoperative Crohn's Disease Recurrence: A Systematic Review and Meta-Analysis

S1030 Adalimumab Is Not Superior to Azathioprine in the Prevention of Postoperative Crohn's Disease Recurrence: A Systematic Review and Meta-Analysis

Intra-abdominal septic complications after ileocolic resection increases risk for endoscopic and surgical postoperative Crohn's disease recurrence.

Postoperative recurrence [POR] of Crohn's disease following ileocolonic resection is common. The impact of immediate postoperative intra-abdominal septic complications [IASC] on endoscopic and surgical recurrence has not been elucidated. To evaluate if IASC is associated with an increased risk for endoscopic and surgical POR. This was a retrospective study of adult Crohn's disease patients undergoing ileocolonic resection with primary anastomosis between 2009 and 2020. IASC was defined as anastomotic leak or intra-abdominal abscess within 90 days of the date of surgery. Multivariable logistic and Cox proportional hazard modelling were performed to assess the impact of IASC on endoscopic POR [modified Rutgeerts' score ≥ i2b] at index postoperative ileocolonoscopy and long-term surgical recurrence. In 535 Crohn's disease patients [median age 35 years, 22.1% active smokers, 35.7% one or more prior resection] had an ileocolonic resection with primary anastomosis. A minority of patients [N = 47; 8.8%] developed postoperative IASC. In total, 422 [78.9%] patients had one or more postoperative ileocolonoscopies, of whom 163 [38.6%] developed endoscopic POR. After adjusting for other risk factors for postoperative recurrence, postoperative IASC was associated with significantly greater odds (adjusted odds ratio [aOR]: 2.45 [1.23-4.97]; p = 0.01) and decreased time (adjusted hazards ratio [aHR]: 1.60 [1.04-2.45]; p = 0.03] to endoscopic POR. Furthermore, IASC was associated with increased risk (aOR: 2.3 [1.04-4.87] p = 0.03) and decreased survival-free time [aHR: 2.53 [1.31-4.87]; p = 0.006] for surgical recurrence. IASC is associated with an increased risk for endoscopic and surgical POR of Crohn's disease. Preoperative optimization to prevent IASC, in addition to postoperative biological prophylaxis, may help reduce the risk for endoscopic and surgical POR.

Vedolizumab may be an effective option for the treatment of postoperative recurrence of Crohn's disease.

The role of Vedolizumab (VDZ) as therapeutic option for the postoperative recurrence of Crohn's disease (CD) following ileocolonic resection is unknown. To assess the effectiveness of VDZ in this setting. All consecutive CD patients with a baseline colonoscopy at 6-12 months from the ileocolonic resection showing postoperative recurrence (Rutgeerts score ≥i2) and treated with VDZ after the baseline colonoscopy were extracted from the cohort of the Sicilian Network for Inflammatory Bowel Diseases (SN-IBD). The primary outcome was endoscopic success, assessed at the first colonoscopy following initiation of VDZ and defined as reduction of at least one point of Rutgeerts score. The secondary outcome was clinical failure, assessed at one year and at the end of follow-up. Fifty-eight patients were included (mean follow-up: 24.8±13.1 months). Endoscopic success was reported in 47.6% of patients. Clinical failure was reported in 19.0% of patients at one year, and in 32.8% of patients at the end of follow-up. A new resection was required in 7 patients (12.1%). VDZ may be an effective option for the treatment of postoperative recurrence of CD.

Deep Learning Analysis of Histologic Images from Intestinal Specimen Reveals Adipocyte Shrinkage and Mast Cell Infiltration to Predict Postoperative Crohn Disease

Most patients with Crohn disease (CD), a chronic inflammatory gastrointestinal disease, experience recurrence despite treatment, including surgical resection. However, methods for predicting recurrence remain unclear. This study aimed to predict postoperative recurrence of CD by computational analysis of histopathologic images and to extract histologic characteristics associated with recurrence. A total of 68 patients who underwent surgical resection of the intestine were included in this study and were categorized into two groups according to the presence or absence of postoperative disease recurrence within 2 years after surgery. Recurrence was defined using the CD Activity Index and the Rutgeerts score. Whole-slide images of surgical specimens were analyzed using deep learning model EfficientNet-b5, which achieved a highly accurate prediction of recurrence (area under the curve,0.995). Moreover, subserosal tissue images with adipose cells enabled highly accurate prediction. Adipose cell morphology showed significant between-group differences in adipose cell size, cell-to-cell distance, and cell flattening values. These findings suggest that adipocyte shrinkage is an important histologic characteristic associated with recurrence. Moreover, there was a significant between-group difference in the degree of mast cell infiltration in the subserosa. These findings show the importance of mesenteric adipose tissue in patient prognosis and CD pathophysiology. These findings also suggest that deep learning-based artificial intelligence enables the extraction of meaningful histologic features.

Isoperistaltic side-to-side anastomosis for the surgical treatment of Crohn disease.

PurposeIncreasing evidence has shown an association of surgical technique, particularly anastomotic configuration, with postoperative recurrence of CD. This pilot study aimed to evaluate short-term outcomes of isoperistaltic side-to-side anastomosis (ISSA) employed on Crohn disease (CD) patients.MethodsData were retrieved from a prospectively maintained database. Postoperatively, all patients were followed up with close endoscopic (ileocolonoscopy) surveillance.ResultsFrom January 2017 to May 2021, 30 patients diagnosed with CD who underwent ISSA were compared with 45 CD patients who underwent antiperistaltic side-to-side anastomosis (ASSA). The 2 groups were comparable in baseline demographics and clinical characteristics. No significant differences were observed between groups regarding postoperative safety issues, including anastomotic leak, abdominal/pelvic abscess, length of hospital stay, readmission rate within 30 days, etc. At postoperative 24th month, reduced endoscopic recurrence was observed in the ISSA group compared with that in the ASSA group (18 of 24, 75.0%, vs. 36 of 38, 94.7%; P = 0.024). Regarding surgical recurrence, there was 0% in the ISSA group vs. 4.4% (2 of 45) in the ASSA group (P = 0.510).ConclusionIn this study, we aimed to explore the influence of ISSA on postoperative recurrence in CD patients, and the preliminary results show that ISSA was technically safe and feasible, and appears to be effective in reducing postoperative recurrence in CD patients. However, our conclusion was underpowered due to small sample size and inadequate follow-up. We proposed ISSA be considered as another alternative option in the toolbox of inflammatory bowel disease surgeons when performing anastomosis on CD patients.

S712 Late Postoperative Crohn's Disease Recurrence Is Common and Differs by Baseline Inflammation

S712 Late Postoperative Crohn's Disease Recurrence Is Common and Differs by Baseline Inflammation

Thiopurines are superior to mesalamine for preventing postoperative recurrence in patients with Crohn's disease and two or more risk factors.

To confirm the hypothesis that thiopurines are better than mesalamine for preventing postoperative recurrence of Crohn's disease (CD) in patients with more than two risk factors. In total 87 consecutive CD patients who underwent curative ileocolonic resection and ileocolic anastomosis were retrospectively recruited, including 43 prescribed with thiopurines and 44 with mesalamine after surgery. Four risk factors were predefined for subgroup analyses: smoking, penetrating disease, perianal disease and previous resection. End-points included clinical (Crohn's disease activity index >200) and endoscopic recurrence (Rutgeerts score ≥i2) within 52 weeks. There were no significant differences in clinical (37.2% vs 54.5%, P=0.105) and endoscopic recurrence (55.8% vs 75.0%, P=0.060) between the thiopurines and mesalamine groups by week 52. In the subgroup analysis of patients with two or more risk factors, clinical (35.7% vs 81.8%, P=0.042) and endoscopic recurrence (64.3% vs 100%, P= 0.046) were less frequent in the thiopurine group than the mesalamine group. With one additional risk factor, the risk of endoscopic recurrence in the thiopurines group increased by 2.201-fold (95% confidence interval [CI] 1.178-4.115), adjusted for treatment intervention. While the risk of clinical and endoscopic recurrence in patients treated with mesalamine increased by 3.383-fold and 5.884-fold (95% CI 1.260-9.081 and 1.598-21.662). Three patients treated with thiopurines withdrew for adverse events. Thiopurines may be superior to mesalamine for preventing postoperative recurrence of CD in patients with two or more risk factors. Caution is needed in light of the adverse events caused by thiopurines.

Quantifying the rate of recurrence of postoperative Crohn's disease with biological therapy. A meta-analysis.

Preventing the postoperative recurrence (POR) of Crohn's disease (CD) poses a significant challenge to clinicians. With the advent of biologics, various studies have observed a reduction of recurrence after surgery. Hence, we performed a systematic review and meta-analysis to identify the rate of POR at different time points in the era of biologic use. We performed a literature search using Medline and Embase databases for studies investigating biologics in preventing the POR of CD. Data were extracted, and a single-arm meta-analysis with generalized linear mixed model and Clopper-Pearson method for confidence interval (CI) was performed to identify endoscopic, clinical and surgical recurrence rates at 6 months and 1, 2 and 5 years postoperatively. Altogether 24 studies were included in the meta-analysis. The endoscopic, clinical and surgical POR rate with the use of anti-tumor necrosis factor (TNF)-α agents at 1 year was 21.72% (95% CI 16.28%-28.37%), 13.06% (95% CI 8.18%-18.92%) and 3.76% (95% CI 1.37%-9.91%), respectively. The 5-year recurrence rate was 84.21% (95% CI 72.35%-91.57%) and 17.49% (95% CI 9.17%-30.80%) for endoscopic and surgical recurrence, respectively. Subgroup analyses at 1 year for the type of anti-TNF-α agent or the timing of initiation after surgery showed no significant difference in endoscopic, clinical and surgical recurrence rates. Anti-TNF-α agents are effective at preventing clinical, endoscopic and surgical POR of CD. The timing of initiating biological therapy after surgery has no significant effect on the rate of POR. The efficacy of infliximab and adalimumab for postoperative recurrence prevention is similar.

A Magnetic Resonance Imaging Index to Predict Crohn’s Disease Postoperative Recurrence: The MONITOR Index

We developed and validated a magnetic resonance imaging-based index to predict Crohn's disease (CD) postoperative recurrence (POR). Patients with CD who underwent a postoperative evaluation for recurrence (with colonoscopy and MRI no longer than 105 days apart) were included between 2006 and 2016 in University Hospital of Nancy, France. MRI items with good levels of intra-rater and inter-rater agreement (Gwet's coefficient ≥0.5) were selected. The MRI in Crohn's Disease to Predict Postoperative Recurrence (MONITOR) index's performance was assessed in terms of the area under the receiver operating characteristic curve (AUROC) and accuracy, by considering the Rutgeerts score as the gold standard. The MONITOR index was validated with a bootstrap method and an independent cohort. Seventy-three MRI datasets were interpreted by 2 radiologists. Seven items (bowel wall thickness, contrast enhancement, T2 signal increase, diffusion-weighted signal increase, edema, ulcers, and the length of the diseased segment) had a Gwet's coefficient ≥0.5 and were significantly associated with the Rutgeerts score, leading to their inclusion in the MONITOR index. All the items had a weighting of 1, except the "ulcers" item weighting 2.5, reflecting the higher adjusted odds ratio. The AUROC [95% confidence interval] for the prediction of endoscopic POR (Rutgeerts score >i1) was 0.80 [0.70-0.90]. The optimal threshold was a MONITOR index ≥1, giving a sensitivity of 79%, a specificity of 55%, a predictive positive value of 68%, and a predictive negative value of 68%. The bootstrap validation gave an AUROC of 0.85 [0.73-0.97]. In the validation cohort, a MONITOR index ≥1 gave a sensitivity of 87%, a specificity of 75%, a predictive positive value of 84.6%, and a predictive negative value of 75%. The MONITOR index is an efficient, reliable, easy-to-apply tool that can be used in clinical practice to predict the POR of CD.

Diagnosis of postoperative recurrence of Crohn disease with MR-enterography: Value of diffusion-weighted imaging

PurposeTo compare the diagnostic capabilities of MR enterography (MRE) using contrast-enhanced (CE) sequences with those of MRE using diffusion-weighted (DW) imaging for the diagnosis of postoperative recurrence at the neo-terminal ileum and/or anastomosis after ileocolonic resection in patients with Crohn disease (CD), and to clarify the role of additional DW imaging to CE-MRE in this context. Material and methodsForty patients who underwent ileal resection for CD, and both endoscopy and MRE within the first year after surgery were included. There were 21 men and 19 women, with a mean age of 38 years±12 (SD) years (range: 18–67 years). MRE examinations were blindly analyzed independently by one senior (R1) and one junior (R2) radiologist for the presence of small bowel postoperative recurrence at the anastomotic site. During a first reading session, T2-, steady-state- and DW-MRE were reviewed (DW-MRE or set 1). During a separate distant session, T2-, steady-state- and CE-MRE were reviewed (CE-MRE or set 2). Lastly, all sequences were analyzed altogether (set 3). Performances of each reader for the diagnosis of postoperative recurrence were evaluated using endoscopic findings as the standard of reference (Rutgeerts score≥i2b). ResultsFifteen patients out of 40 (37.5%) had endoscopic postoperative recurrence at the anastomotic site. Sensitivity for the diagnosis of postoperative recurrence was 73% (95% CI: 51–96%) for R1 and 67% (95% CI: 43–91%) for R2 using set 1, and 80% (95% CI: 60–100%) for both readers using set 2. There was no significant differences in sensitivity between reading set 1 and reading set 2, for either R1 or R2 (R1, P> 0.99; R2, P=0.48). Specificity was 96% (95% CI: 88–100%) for both readers using set 1 or using set 2. Reading set 3 yielded an area under the ROC curve (AUC) of 0.93 (95% CI: 0.84–1) versus 0.89 (95% CI: 0.75–1) with set 1 (P=0.18) and versus 0.89 (95% CI: 0.78–1) with set 2 (P=0.21). No significant differences in AUC were found between set 1 or 2 and set 3 (P=0.18), nor between set 1 and 2 (P=0.76). Accuracies were 88% (95% CI: 74–95%) and 85% (95% CI: 71–93%) for DW-MRE for R1 and R2, respectively; 90% (95% CI: 77–96%) for CE-MRE for both readers; and 93% (95% CI: 80–97%) and 88% (95% CI: 74–95%) for R1 and R2 with set 3, respectively. ConclusionDW-MRE has diagnostic capabilities similar to those of CE-MRE for the diagnosis of postoperative recurrence of CD at the anastomotic site.