Histologic features predicting postoperative Crohn's disease recurrence

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

PURPOSE OF REVIEW

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.

RECENT FINDINGS

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.

Neutrophil diversity in inflammation and cancer

Neutrophils are the most abundant circulating leukocytes in humans and the first immune cells recruited at the site of inflammation. Classically perceived as short-lived effector cells with limited plasticity and diversity, neutrophils are now recognized as highly heterogenous immune cells, which can adapt to various environmental cues. In addition to playing a central role in the host defence, neutrophils are involved in pathological contexts such as inflammatory diseases and cancer. The prevalence of neutrophils in these conditions is usually associated with detrimental inflammatory responses and poor clinical outcomes. However, a beneficial role for neutrophils is emerging in several pathological contexts, including in cancer. Here we will review the current knowledge of neutrophil biology and heterogeneity in steady state and during inflammation, with a focus on the opposing roles of neutrophils in different pathological contexts.

Prophylactic Medication for the Prevention of Endoscopic Recurrence in Crohn's Disease: a Prospective Study Based on Clinical Risk Stratification

BACKGROUND

To prevent recurrence after ileocolonic resection [ICR] in Crohn's disease [CD], postoperative prophylaxis based on risk stratification is recommended in international guidelines. This study aimed to evaluate postoperative CD recurrence after implementation of a clinical management algorithm and to determine the predictive value of clinical and histological risk factors [RFs].

METHODS

In this multicentre, prospective cohort study, CD patients [≥16 years] scheduled for ICR were included. The algorithm advised no postoperative medication for low-risk patients, and treatment with prophylaxis [immunosuppressant/biological] for high-risk patients [≥1 RF: active smoking, penetrating disease, prior ICR]. Clinical and histological RFs [active inflammation, granulomas, plexitis in resection margins] for endoscopic recurrence [Rutgeerts' score ≥i2b at 6 months] were assessed using logistic regression and ROC curves based on predicted probabilities.

RESULTS

In total, 213 CD patients after ICR were included [age 34.5 years; 65% women] (93 [44%] low-risk; 120 [56%] high-risk: 45 [38%] smoking; 51 [43%] penetrating disease; 51 [43%] prior ICR). Adherence to the algorithm was 82% in low-risk [no prophylaxis] and 51% in high-risk patients [prophylaxis]. Endoscopic recurrence was higher in patients treated without prophylaxis than with prophylaxis in both low [45% vs 16%, p = 0.012] and high-risk patients [49% vs 26%, p = 0.019]. Clinical risk stratification including the prescription of prophylaxis corresponded to an area under the curve [AUC] of 0.70 (95% confidence interval [CI] 0.61-0.79). Clinical RFs combined with histological RFs increased the AUC to 0.73 [95% CI 0.64-0.81].

CONCLUSION

Adherence to this management algorithm is 65%. Prophylactic medication after ICR prevents endoscopic recurrence in low- and high-risk patients. Clinical risk stratification has an acceptable predictive value, but further refinement is needed.

Integrating Radiomics With Clinicoradiological Scoring Can Predict High-Risk Patients Who Need Surgery in Crohn's Disease: A Pilot Study

BACKGROUND

Early identification of Crohn's disease (CD) patients at risk for complications could enable targeted surgical referral, but routine magnetic resonance enterography (MRE) has not been definitively correlated with need for surgery. Our objective was to identify computer-extracted image (radiomic) features from MRE associated with risk of surgery in CD and combine them with clinical and radiological assessments to predict time to intervention.

METHODS

This was a retrospective single-center pilot study of CD patients who had an MRE within 3 months prior to initiating medical therapy. Radiomic features were extracted from annotated terminal ileum regions on MRE and combined with clinical variables and radiological assessment (via Simplified Magnetic Resonance Index of Activity scoring for wall thickening, edema, fat stranding, ulcers) in a random forest classifier. The primary endpoint was high- and low-risk groups based on need for surgery within 1 year of MRE. The secondary endpoint was time to surgery after treatment.

RESULTS

Eight radiomic features capturing localized texture heterogeneity within the terminal ileum were significantly associated with risk of surgery within 1 year of treatment (P < .05); yielding a discovery cohort area under the receiver-operating characteristic curve of 0.67 (n = 50) and validation cohort area under the receiver-operating characteristic curve of 0.74 (n = 23). Kaplan-Meier analysis of radiomic features together with clinical variables and Simplified Magnetic Resonance Index of Activity scores yielded the best hazard ratio of 4.13 (P = (7.6 × 10-6) and concordance index of 0.71 in predicting time to surgery after MRE.

CONCLUSIONS

Radiomic features on MRE may be associated with risk of surgery in CD, and in combination with clinicoradiological scoring can yield an accurate prognostic model for time to surgery.

Histological Indices and Risk of Recurrence in Crohn's Disease: A Retrospective Study of a Cohort of Patients in Endoscopic Remission

BACKGROUND

Although histological healing is raising interest in ulcerative colitis to predict recurrence, its meaning in Crohn's disease (CD) remains unknown. We aimed to study the performances of different histological indices to predict recurrence of CD patients with mucosal healing.

METHODS

Crohn's disease patients with mucosal healing diagnosed between 2010 and 2018 were included if there was available clinical and endoscopical data. Nancy Histological index (NHI), Geboes score (GS), Robarts Histopathology index (RHI), Global Histological Disease Activity Score (GHAS), and Inflammatory Bowel Disease-Distribution Chronicity Activity score (IBD-DCA) were independently assessed by 3 pathologists.

RESULTS

Eighty-eight patients were included, of which 28 relapsed (32%) within 30.5 months. All 4 histological indices were associated with recurrence, with significant relapse risk (NHI, odds ratio [OR], 1.67; GHAS, OR, 2.33; RHI, OR, 1.19; GS, OR, 2.09; and IBD-DCA, OR, 2.14). Microscopic activity was significantly associated with relapse only with the IBD-DCA score. Predicting performances of all these scores were poor. Calibration curves indicate that the GHAS and IBD-DCA are the closest to the ideal predicted probability curve and thus could better predict recurrence than the other scores. Interobserver agreement varied from poor for GHAS (k = .39) to good for RHI (k = .68).

CONCLUSIONS

Histological scores are valuable indicators to predict recurrence. Histological assessment of activity seems insufficient to predict CD course with most of the score evaluated, highlighting the need for new indices or adaptation of actual scores to CD specificities.

Specific Neuropeptide Expression in Crohn's Disease Ileocolonic Resection Specimens Is Not Associated with Plexitis at the Ileal Margin or Postoperative Recurrence

BACKGROUND

Myenteric plexitis is considered a risk factor for postoperative recurrence (POR) in Crohn's disease (CD). The primary purpose of this study was to evaluate the association between neuropeptide Y (NPY), vasoactive intestinal peptide (VIP), and substance P (SP) expression and plexitis at the proximal resection margin. The secondary aim was to identify risk factors for POR.

METHODS

A retrospective, single-center study on CD patients who underwent ileocolonic resection (ICR) between January 2010 and December 2016 was conducted. The presence and severity of plexitis were evaluated by hematoxylin and eosin stain. Mast cells were highlighted by Giemsa stain. Immunohistochemistry was used to identify T lymphocytes and NPY-, VIP-, and SP-ergic neurons. Neuropeptide expression was quantified using image analysis.

RESULTS

Seventy-nine patients were included. No association was detected between NPY, VIP, and SP expression and plexitis. Similarly, the number of involved inflammatory cells, T lymphocytes or mast cells was not correlated with neuropeptide expression. Smoking (hazard ratio [HR] 4.07; 95% confidence interval [CI] 2.08-7.94; p < 0.001), moderate (HR 3.68; 95%CI 1.06-12.73; p = 0.040), and severe myenteric plexitis (HR 7.36; 95%CI 1.12-48.30; p = 0.037) were independent risk factors for endoscopic POR, whereas smoking (HR 2.78; 95%CI 1.01-7.67; p = 0.049), severe myenteric plexitis (HR 20.03; 95%CI 1.09-368.28; p = 0.044), and involved ileal margin (HR 3.45; 95%CI 1.33-8.96; p = 0.011) for clinical POR.

CONCLUSIONS

Smoking, moderate or severe myenteric plexitis, and involved ileal margin negatively affect POR in CD patients undergoing ICR. Submucosal and myenteric plexitis at the proximal resection margin is not related to the expression of specific neuropeptides.

Positive histologic margins is a risk factor of recurrence after ileocaecal resection in Crohn's disease

INTRODUCTION

Surgical resection is not curative in Crohn's disease (CD) and, recurrence after surgery is a common situation. The identification of patients at high risk of recurrence remains disappointing in clinical practice.

OBJECTIVE

To evaluate the impact of residual microscopic disease on margins on the risk of recurrence after ileocaecal resection in CD.

PATIENTS AND METHODS

All patients who underwent ileocaecal resection between January 1992 and December 2016 were prospectively identified. Demographic data, clinical, surgical and histological variables were retrospectively collected. Positive histologic margin was assessed prospectively and defined by the presence of acute inflammatory lesions on margins: erosion, ulceration, chorion infiltration by neutrophils, cryptic abscesses or cryptitis.

RESULTS

One hundred twenty five patients were included, with a median follow-up of 8 years (Interquartile Range (IQR), 4.3-15.2). Half (49.6%, n = 62) were women, and the median age at surgery was 33 years (IQR, 24-42). Fifty-six (44.8%) had positive inflammatory margins. Five years after surgery, respectively 29 (51%) and 23 (34%) patients with positive and negative margins had clinical recurrence (p = 0.034). At the end of the follow-up, respectively 60% (n = 34) and 47% (n = 33) patients had clinical recurrence (p = 0.07). CD-related hospitalizations were observed in respectively 37.5% (n = 21) and 18.8% (n = 13) with positive and negative margins (p = 0.02). Fourteen patients (25%) with positive intestinal margins had surgical recurrence at the end of the follow-up compared to 5 patients (7%) with negative margins (p = 0.04). Multivariate analysis confirmed that positive intestinal margin was independently associated with surgical recurrence (OR, 4.7 (CI95%, 1.4-15.3), p = 0.01).

CONCLUSION

Positive histologic margin was associated with an increased risk of clinical and surgical recurrence after ileocaecal resection for Crohn's disease.

Predictive value of tissue calprotectin for disease recurrence after ileocecal resection in pediatric Crohn's disease

AIM

Detection of possible predictive factors of endoscopic recurrence after ileocecal resection in Crohn's disease could be very beneficial for the individual adjustment of postoperative therapy. The aim of this study was to verify, whether immunohistochemical detection of calprotectin in resection margins is useful in diagnostics of endoscopic recurrence.

METHODS

In this study we included pediatric patients with Crohn's disease who underwent ileocecal resection, regardless of pre-operative or post-operative therapy (n=48). We collected laboratory, clinical, surgical, endoscopic and histopathological data at the time of surgery and at 6 months after surgery. The immunohistochemical staining of calprotectin antigen was performed on all paraffin blocks from the resection margins.

RESULTS

Out of 48 patients 52% had endoscopic recurrence in the anastomosis (defined by Rutgeerts score) within 6 months after surgery. The number of cells positive for calprotectin in the proximal resection margin was negatively associated with recurrence (P=0.008), as was the elevated level of total calprotectin (from both resection margins). There was no correlation of calprotectin in distal resection margin and endoscopic recurrence. Fecal calprotectin over 100 ug/g (P=0.0005) and high CRP (P<0.001) at 6 months after ileocecal resection and peritonitis (P=0.048) were associated with endoscopic recurrence.

CONCLUSION

Approximately half of the patients developed endoscopic recurrence within 6 months after ileocecal resection. The predictive value of tissue calprotectin is questionable, as it is negatively associated with endoscopic recurrence. There are other potentially useful predictors, such as CRP and fecal calprotectin at 6 months after resection and the presence of peritonitis.

Active Margins, Plexitis, and Granulomas Increase Postoperative Crohn's Recurrence: Systematic Review and Meta-analysis

BACKGROUND & AIMS

Rates of postoperative Crohn's disease recurrence remain high, although the ability to predict this risk of recurrence remains limited. As such, we aimed to determine the association of histologic features at the time of resection with postoperative recurrence.

METHODS

Electronic databases were searched through February 2020 for studies that reported risk of clinical, endoscopic, or surgical postoperative recurrence in patients with positive resection margins, plexitis, or granulomas in the index specimen. Pooled risk ratios (RRs) with 95% CIs were calculated for this risk in patients with and without these histologic features.

RESULTS

Twenty-one studies (2481 patients) assessed positive resection margins, 10 studies (808 patients) assessed plexitis, and 19 studies (1777 patients) assessed granulomas. Positive resection margins increased the risk of clinical (RR, 1.26; 95% CI, 1.06-1.49; I² = 41%) and surgical (RR, 1.87; 95% CI, 1.14-3.08; I² = 71%) recurrence, with a trend toward endoscopic recurrence (RR, 1.56; 95% CI, 0.79-3.05; I² = 85%). Granulomas increased the risk of clinical (RR, 1.31; 95% CI, 1.05-1.64; I² = 36%) and endoscopic (RR, 1.37; 95% CI, 1.00-1.87; I² = 49%) recurrence, with a trend toward surgical recurrence (RR, 1.58; 95% CI, 0.89-2.80; I² = 75%). Plexitis increased the risk of endoscopic recurrence (RR, 1.31; 95% CI, 1.00-1.72; I² = 20%), with a trend toward clinical recurrence (RR, 1.34; 95% CI, 0.95-1.91; I² = 46%).

CONCLUSIONS

Positive resection margins, granulomas, and plexitis are predictive of postoperative Crohn's disease recurrence and should be recorded at the time of index resection.

Medical therapies for postoperative Crohn's disease

Postoperative recurrence of Crohn's disease is common and requires a multidisciplinary approach between surgeons and gastroenterologists in the perioperative and postoperative period to improve outcomes in this patient population. Endoscopic recurrence precedes clinical and surgical recurrence and endoscopic monitoring is crucial to guide postoperative management. Risk stratification of patients is recommended to guide early prophylactic management, and follow-up endoscopic monitoring can guide intensification of therapy. This review summarizes evidence behind postoperative recurrence rates, disease monitoring techniques, nonbiologic and biologic therapies available to prevent and treat postoperative recurrence, risk factors associated with recurrence, and postoperative management strategies guided by endoscopic monitoring.

The Role of Inflammation in Crohn's Disease Recurrence after Surgical Treatment

Introduction

Postoperative recurrence after surgery for Crohn's disease (CD) is virtually inevitable, and its mechanism is poorly known.

Aim

To review the numerous factors involved in CD postoperative recurrence (POR) pathogenesis, focusing on single immune system components as well as the immune system as a whole and highlighting the clinical significance in terms of preventive strategies and future perspectives.

Methods

A systematic literature search on CD POR, followed by a review of the main findings.

Results

The immune system plays a pivotal role in CD POR, with many different factors involved. Memory T-lymphocytes retained in mesenteric lymph nodes seem to represent the main driving force. New pathophysiology-based preventive strategies in the medical and surgical fields may help reduce POR rates. In particular, surgical strategies have already been developed and are currently under investigation.

Conclusions

POR is a complex phenomenon, whose driving mechanisms are gradually being unraveled. New preventive strategies addressing these mechanisms seem promising.

The Predictive Value of Inflammation at Ileocecal Resection Margins for Postoperative Crohn's Recurrence: A Cohort Study

BACKGROUND

Resections for Crohn's disease should be limited and only resect macroscopically affected bowel. However, recent studies suggest microscopic inflammation at resection margins as a predictor for postoperative recurrence. The clinical impact remains unclear, as non-uniform pathological criteria have been used. The aim of this study was to assess the predictive value of pathological characteristics at ileocecal resection margins for recurrence.

METHODS

Both resection margins of 106 consecutive patients undergoing ileocecal resection for Crohn's disease between 2002 and 2009 were revised and scored for active inflammation, myenteric plexitis, and granulomas. Pathological findings were correlated to recurrence, defined as recurrent disease activity demonstrated by endoscopy (modified Rutgeerts score ≥i2) requiring upscaling medical treatment, using multivariate analysis.

RESULTS

Active inflammation was found at the proximal and distal resection margin in 27% and 15% of patients, respectively, myenteric plexitis in 37% and 32%, respectively, and granulomas in 4% and 6%, respectively. In total, 47 out of 106 patients developed recurrence. Only active inflammation at the distal colonic resection margin was an independent significant predictor for recurrence (88% vs 43% vs 51% for distal, proximal, and no involved margins, respectively; P < 0.01).

CONCLUSION

Active inflammation at the distal colonic resection margin after ileocecal resection identifies a patient group at high risk for postoperative recurrence both at the anastomotic site and the colon because it identifies undiagnosed L3 disease. These patients have a different and more aggressive natural history and require more intense medical treatment. Therefore, pathological evaluation of the distal resection margin should be implemented in daily practice.

Prevention of Postoperative Recurrence in CD: Tailoring Treatment to Patient Profile

Crohn's disease (CD) is an immune-mediated condition characterized by the transmural inflammation of the gut tissue, associated with progressive bowel damage often leading to surgical intervention. As operative resection of the damaged segment is not curative, a majority of patients undergoing intestinal resections for complicated CD present disease recurrence within 3 years after the intervention. Postoperative recurrence can be defined as endoscopic, clinical, radiological or surgical. Endoscopic recurrence rates within 1 year exceed 60% and the severity, according to the Rutgeerts' score, is associated with worse prognosis and can predict clinical recurrence (in up to 1/3 of the patients). Most importantly, about 50% of patients will undergo a reoperation after 10 years of their first intestinal resection. Therefore, the prevention of postoperative recurrence in CD remains a challenge in clinical practice and should be properly managed. We aim to summarize the most recent data on the definition, risk factors, assessment and treatment of postoperative CD recurrence.

Mesenteric excision surgery or conservative limited resection in Crohn's disease: study protocol for an international, multicenter, randomized controlled trial

Background

The structures of the mesentery including adipose tissue, nerves, and lymphatics play an important role in the pathogenesis and disease progression of Crohn’s disease (CD). Conventional surgical resection for CD usually does not involve resecting the mesentery en bloc with the specimen. This contrasts with complete mesocolic excision (CME) in colorectal cancer, which involves radical resection of the mesentery. Preliminary evidence from smaller studies suggests that applying the principle of mesocolic excision to CD surgery may reduce the risk of postoperative recurrence. This randomized controlled trial is designed to test whether applying the principles of mesocolic excision to CD results in reduced postoperative recurrence. It also aims to evaluate intra- and postoperative morbidity between the two approaches.

Methods

This international, multicenter, randomized controlled trial will randomize patients (n = 116) scheduled to undergo primary ileocolic resection to either receive extensive mesenteric excision (EME) or conventional ileocolic resection with limited mesenteric excision (LME). Five sites will recruit patients in three countries. In the EME group, the mesentery is resected following CME, while avoiding the root region, i.e., 1 cm from the root of the ileocolic artery and vein. In the LME group, the mesentery is retained, i.e., “close shave” or < 3 cm from the border of bowel. The primary end point will be surgical recurrence after surgery. The secondary end points will be the postoperative endoscopic and clinical recurrence, and intra- and postoperative morbidity. Demographics, risk factors, laboratory investigations, endoscopy, postoperative prophylaxis and imaging examination will be assessed. Analysis of the primary outcome will be on an intention-to-treat basis.

Discussion

If mesocolic excision in CD reduces postoperative disease recurrence and does not increase morbidity, this trial has the potential to change practice and reduce recurrence of CD after surgical resection.

Trial registration

Clinical Trials.gov, ID: NCT03769922. Registered on February 27, 2019.

Histopathology Scoring Systems of Stenosis Associated With Small Bowel Crohn's Disease: A Systematic Review

BACKGROUND & AIMS

Stenosis is a common complication of Crohn's disease (CD) that has no effective medical therapy. Development of antifibrotic agents will require testing in randomized controlled trials. Computed tomography enterography- and magnetic resonance enterography-based technologies might be used to measure outcomes in these trials. These approaches have been validated in studies of patients with symptomatic strictures who underwent imaging evaluations followed by resection with histopathologic grading of the intestinal tissue for inflammation and/or fibrosis (the reference standard). Imaging findings have correlated with findings from quantitative or semiquantitative histologic evaluation of the degree of fibromuscular stenosis and/or inflammation on the resection specimen. However, it is not clear whether histologic findings are an accurate reference standard. We performed a systematic review of all published histologic scoring systems used to assess stenosing CD.

METHODS

We performed a comprehensive search of Embase and MEDLINE of studies through March 13, 2019, that used a histologic scoring system to characterize small bowel CD and assessed inflammatory and fibrotic alterations within the same adult individual. All scores fitting the criteria were included in our analysis, independent of the presence of stricturing disease, as long as inflammation and fibrosis were evaluated separately but in the same scoring system.

RESULTS

We observed substantial heterogeneity among the scoring systems, which were not derived from modern principles for evaluative index development. None had undergone formal validity or reliability testing. None of the existing indices had been constructed according to accepted methods for the development of evaluative indices. Basic knowledge regarding their operating properties were lacking. Specific indices for evaluating the important pathologic component of myofibroblast hypertrophy or hyperplasia have not been proposed.

CONCLUSIONS

In a systematic review of publications, we found a lack of validated histopathologic scoring systems for assessment of fibromuscular stenosis. Data that describe the operating properties of existing cross-sectional imaging techniques for stenosing CD should be questioned. Development and validation of a histopathology index is an important research priority.

Hypergravity disrupts murine intestinal microbiota

During spaceflight, organisms are subjected to various physical stressors including modification of gravity (G) that, associated with lifestyle, could lead to impaired immunity, intestinal dysbiosis and thus potentially predispose astronauts to illness. Whether space travel affects microbiota homeostasis has not been thoroughly investigated. The aim of this study was to evaluate changes in intestinal microbiota and mucosa in a ground-based murine model consisting in a 21-days confinement of mice in a centrifuge running at 2 or 3G. Results revealed an increased α-diversity and a significant change in intracaecal β-diversity observed only at 3G, with profiles characterized by a decrease of the Firmicutes/Bacteroidetes ratio. Compared to 1G microbiota, 12.1% of the taxa were significantly impacted in 3G microbiota, most of them (78%) being enriched. This study shows a G-level-dependent disruption of intracaecal microbiota, without alteration of mucosal integrity. These first data reinforce those recently obtained with in-flight experimentations or microgravity models, and emphasize the critical need for further studies exploring the impact of spaceflight on intestinal microbiota in order to optimize long-term space travel conditions.

Quantitative assessment of mucosal architecture using computer-based analysis of confocal laser endomicroscopy in inflammatory bowel diseases

BACKGROUND AND AIMS

Confocal laser endomicroscopy (CLE) might discriminate mucosal lesions between Crohn's disease (CD) and ulcerative colitis (UC). However, the analysis of CLE images requires time-consuming methods, a long training time, and potential impediments, such as significant interobserver variability. Therefore, we developed a computer-based method to analyze mucosal architecture from CLE images and discriminate between healthy subjects and patients with inflammatory bowel disease (IBD) as well as between UC and CD patients.

METHODS

We retrospectively screened patients who had undergone CLE either for an evaluation of IBD in remission or for colorectal cancer screening (control subjects) between 2009 and 2016. We assessed 14 morphologic and functional parameters in each CLE recording from 23 CD patients, 27 UC patients, and 9 control patients. Next, we constructed 2 scores, 1 for the IBD diagnosis and 1 for the differential diagnosis between UC and CD.

RESULTS

In IBD patients, the mean intercrypt distance, wall thickness, and fluorescein leakage through the colonic mucosa were significantly increased compared with control patients by 155%, 188%, and 297%, respectively (P < .05). In UC patients, the same parameters were significantly increased by 109%, 117%, and 174%, respectively (P < .05), compared with CD patients. IBD diagnosis had 100% (95%CI, 93%; 100%) sensitivity and 100% (95%CI, 66%; 100%) specificity. IBD differential diagnosis provided discrimination of UC from CD patients with 92% (95%CI, 75%; 99%) sensitivity and 91% (95%CI, 72%; 99%) specificity.

CONCLUSIONS

Confirming these results using prospective validation cohorts can substantiate that computer-based analysis of CLE images may provide new biomarkers for the diagnosis and characterization of IBD.

What is the role of histopathology in the evaluation of disease activity in Crohn's disease?

Assessment of disease activity is essential for developing and determining appropriate therapy in patients with Crohn's disease. Currently, clinical and endoscopic treatment targets have been proposed, whereas histologic assessment of disease activity is not recommended in expert guidelines. Histologic assessment of disease activity has emerged as an important tool in ulcerative colitis as persistent histological inflammation is associated with clinical relapse, corticosteroid use, hospitalisation, and development of dysplasia. Similar data for Crohn's disease is limited but emerging literature suggests that histologic evaluation of disease activity may have value. This review summarizes the recent literature regarding histologic evaluation of disease activity in Crohn's disease. Correlation between histologic, endoscopic, and other markers of disease activity are discussed. Histologic scoring systems in Crohn's disease are described and practical guidance is provided to gastroenterologists and pathologists on how to report and interpret histologic data.

Mesenteric Lymphatic Vessel Density Is Associated with Disease Behavior and Postoperative Recurrence in Crohn's Disease

PURPOSE

The aims of the present study were to examine the density of lymphatic vessels in the mesentery and to assess the predictive value of the mesenteric lymphatic vessel density for postoperative clinical recurrence.

METHODS

Ileocolonic resection specimens were obtained from 53 patients with Crohn's disease and 10 non-inflammatory bowel disease control subjects. Mesentery adipose tissues adjacent to the bowel wall were used for the histological quantification of lymphatic vessels using immunohistochemistry with the D2-40 antibody. The relationships between lymphatic vessel density and disease behavior, the presence of granulomas, the presence of creeping fat, and postoperative clinical recurrence were assessed.

RESULTS

Median lymphatic vessel density in the mesentery adjacent to inflamed or non-inflamed intestine was lower in control subjects than in Crohn's disease patients (2.13‰; interquartile range [IQR], 1.83-2.61; 8.34‰; IQR, 6.39-10.22; 4.43‰; IQR, 3.32-5.78; P ˂ 0.001). Increased mesenteric lymphatic vessel density was significantly associated with stricturing behavior, the presence of intestinal granulomas, the presence of creeping fat, and bowel thickness. Interestingly, patients with disease recurrence had an increased mesenteric lymphatic vessel density of the proximal mesenteric margin at the time of resection compared with those who did not have disease recurrence (6.23‰; IQR, 5.43-6.75 vs. 3.28‰; IQR, 2.93-4.29; P ˂ 0.001).

CONCLUSIONS

In addition to its correlation with disease behavior, bowel thickness, and the presence of intestinal granulomas and creeping fat, increased mesenteric lymphatic vessel density in the proximal margin is predictive of early clinical recurrence after surgery in patients with Crohn's disease.

Obstructive Lymphangitis Precedes Colitis in Murine Norovirus-Infected Stat1-Deficient Mice

Murine norovirus (MNV) is an RNA virus that can prove lethal in mice with impaired innate immunity. We found that MNV-4 infection of Stat1-/- mice was not lethal, but produced a 100% penetrant, previously undescribed lymphatic phenotype characterized by chronic-active lymphangitis with hepatitis, splenitis, and chronic cecal and colonic inflammation. Lesion pathogenesis progressed from early ileal enteritis and regional dilated lymphatics to lymphangitis, granulomatous changes in the liver and spleen, and, ultimately, typhlocolitis. Lesion development was neither affected by antibiotics nor reproduced by infection with another enteric RNA virus, rotavirus. MNV-4 infection in Stat1-/- mice decreased expression of vascular endothelial growth factor (Vegf) receptor 3, Vegf-c, and Vegf-d and increased interferon (Ifn)-γ, tumor necrosis factor-α, and inducible nitric oxide synthase. However, anti-IFN-γ and anti-tumor necrosis factor-α antibody treatment did not attenuate the histologic lesions. Studies in Ifnαβγr-/- mice suggested that canonical signaling via interferon receptors did not cause MNV-4-induced disease. Infected Stat1-/- mice had increased STAT3 phosphorylation and expressed many STAT3-regulated genes, consistent with our findings of increased myeloid cell subsets and serum granulocyte colony-stimulating factor, which are also associated with increased STAT3 activity. In conclusion, in Stat1-/- mice, MNV-4 induces lymphatic lesions similar to those seen in Crohn disease as well as hepatitis, splenitis, and typhlocolitis. MNV-4-infected Stat1-/- mice may be a useful model to study mechanistic associations between viral infections, lymphatic dysfunction, and intestinal inflammation in a genetically susceptible host.

Mesenteric organ lymphatics and inflammatory bowel disease

Inflammatory bowel disease (IBD) is a complex gastrointestinal disorder and its etiology is unclear yet. Current theory in IBD is focused on genetics, immunity and intestinal microbes. Emerging clinical evidence and experimental results suggest that morphologic abnormalities and dysfunction of mesenteric lymphatics may have potential roles in the pathogenesis and disease course of IBD. In this review, we summarize the findings of specific investigations of the lymphatics and explore its role in IBD.

Increased enteric glial cells in proximal margin of resection is associated with postoperative recurrence of Crohn's disease

BACKGROUND AND AIM

The enteric nervous system can amplify or modulate intestinal inflammation through secretion of neuropeptides, and enteric glial cells have been implicated in the pathophysiology of Crohn's disease. The goal of the study was to search for an association between the density of neurons, neuropeptides, and enteric glial cells and postoperative recurrence.

METHODS

The ileal proximal uninflamed section from ileocolonic sample was studied using immunohistochemistry with antibodies directed against vasoactive intestinal polypeptide (VIP), substance P (SP), neuron-specific enolase (NSE), and the glial marker protein S100. The density in the submucosa was calculated, and the relationship of the density of VIP, SP, NSE, and S100 and postoperative disease recurrence was assessed.

RESULTS

There were no significant differences between patients with and without postoperative endoscopic recurrence or clinical recurrence for the density of NSE-positive, VIP-positive, or SP-positive neurons in the proximal margin. Interestingly, the density of S100-positive enteric glial cells was significantly increased in patients with endoscopic and clinical recurrence than in subjects without disease recurrence (P ˂ 0.001). The density of S100-positive enteric glial cells was independently associated with postoperative disease recurrence.

CONCLUSIONS

Increased S100-positive enteric glial cells are associated with a high risk of both endoscopic and clinical recurrence after surgery. These findings have implications in individualized postoperative prophylaxis for Crohn's disease.

Association of granulomas in mesenteric lymph nodes in Crohn's disease with younger age and transmural inflammation

BACKGROUND AND AIMS

Mesenteric lymph nodes were usually removed during bowel resection surgery for Crohn's disease (CD). Mesenteric lymph node (MLN) granuloma predicted postoperative disease recurrence in patients with CD after ileocolic resection (ICR). This study was aimed to identify factors associated with MLN granulomas in a cohort of CD patients who underwent ICR.

METHODS

The study group consisted of 18 patients with CD who underwent the index ICR between 2004 and 2012 and had MLN granulomas. The control group included 32 cases negative for MLN granulomas, which were randomly selected from the same period. Clinicodemographic and histological features were compared in these two groups.

RESULTS

The presence of MLN granuloma was associated with younger age, perianal disease, and ileocolic disease. Gender, body mass index, smoking status, disease duration, extraintestinal manifestation, length of bowel resected, total number of nodes examined, medical treatment, and indications for surgery were not significantly different between the groups. The presence of MLN granuloma was associated with mural granuloma, transmural inflammation, mural abscess, hypertrophy of the muscularis propria, fibrosis of the muscularis propria, and serosal fibrosis in the small bowel. The multivariable analysis confirms that MLN granuloma was associated with age and transmural inflammation.

CONCLUSIONS

In CD patients who underwent the index ICR, the presence of MLN granuloma was associated with younger age and transmural inflammation. Our current results suggest that the detection of MLN granulomas may be enhanced in patients at higher risk, that is, younger patients or those with transmural inflammation on imaging or histopathology.

Genetic and environmental factors significant for the presentation and development of inflammatory bowel disease

OBJECTIVES

The aim of the study was to evaluate associations between inflammatory bowel disease (IBD) presentation and variants in NOD2, TLR4, TNF-α, IL-6, IL-1β, and IL-RN genes in order to identify possible environmental factors that may affect IBD occurrence, investigate potential predictors for surgical treatment of IBD, and correlate the presence of granulomas in biopsy specimens with clinical characteristics of Crohn's disease (CD) patients.

PATIENTS AND METHODS

We genotyped 167 IBD patients using PCR-based methodology and tested for disease genotype-phenotype associations.

RESULTS

In CD patients ileal localization of disease was more frequent in NOD2 variant carriers. Ileal CD was associated with IL-6 GC+CC genotypes, identifying C allele as a possible marker of increased risk for ileal CD. In CD patients a positive family history for IBD was related to earlier onset of disease, higher risk for CD-related surgery, and appendectomy. CD patients who are TLR4 299Gly carriers are at higher risk for surgery at onset of the disease compared with TLR4 299Asp variant carriers. The presence of granuloma in biopsy specimens was more frequent in patients in whom a diagnosis of CD was made during emergency surgery. Multivariate analysis showed that CD carriers of the 299Gly allele had a 4.6-fold higher risk for emergency surgery before CD diagnosis is established compared with noncarriers, suggesting an aggressive disease course. Granuloma in endoscopic biopsies is detected 5.4-fold more frequently in patients treated surgically at the time of diagnosis.

CONCLUSION

Genetic variants together with epidemiological and clinical data of IBD patients could potentially be used as predictors of the disease course.

Misbalance in type III collagen formation/degradation as a novel serological biomarker for penetrating (Montreal B3) Crohn's disease

BACKGROUND

Misbalances in extracellular matrix turnover are key factors in the development of stricturing (Montreal B2) and penetrating (Montreal B3) Crohn's disease.

AIM

To determine whether serological markers for collagen formation and degradation could serve as biomarkers for complications of Crohn's disease.

METHODS

Serum biomarkers for type I, III, V and VI collagen formation (P1NP, Pro-C3, Pro-C5, Pro-C6) and matrix metalloproteinase mediated degradation (C1M, C3M, C5M and C6M) were measured in a retrospective, single centre cohort of 112 patients with Crohn's disease in the terminal ileum (nonstricturing/nonpenetrating: n=40, stricturing: n=55, penetrating: n=17) and 24 healthy controls. Active inflammation was defined as CRP >5 mg/L.

RESULTS

C3M and Pro-C5 levels were higher in penetrating vs nonpenetrating/nonstricturing and stricturing disease (33.6±5 vs 25.8±2.2 [P=.004] and 27.2±2.3 [P=.018] nmol/L C3M, 1262.7±259.4 vs 902.9±109.9 [P=.005] and 953.0±106.4 [P=.015] nmol/L Pro-C5). C1M (71.2±26.1 vs 46.2±6.2 nmol/L [P<.001]), C3M (31.6±3.9 vs 26.1±1.6 nmol/L [P=.002] and Pro-C5 levels (1171.7±171.5 vs 909.6±80.4 nmol/L [P=.002]) were higher in patients with active inflammation vs without active inflammation. Pro-C3/C3M-ratios were best to differentiate between penetrating vs nonstricturing/nonpenetrating and stricturing disease with area under the curves of 0.815±0.109 (P<.001) and 0.746±0.114 (P=.002) respectively.

CONCLUSIONS

Serological biomarkers show that penetrating Crohn's disease is characterised by increased matrix metalloproteinase-9 degraded type III collagen and formation of type V collagen. Active inflammation in Crohn's disease is characterised by increased formation of type V collagen and increased matrix metalloproteinase mediated breakdown of type I, III collagen. Pro-C3/C3M ratios are superior in differentiating between penetrating Crohn's disease vs inflammatory and stricturing Crohn's disease.

Disease activity and mucosal healing in inflammatory bowel disease: a new role for histopathology?

Histologic evaluation of disease activity in the setting of inflammatory bowel disease is gaining interest within the gastroenterology community. Recent data suggests that histologic measurements of inflammation in ulcerative colitis are more sensitive at detecting disease activity and perform better than endoscopic measurements in predicting clinical outcomes. Histologic measurements are also increasingly used in ulcerative colitis clinical trials to assess response to new therapies. Histologic measurements of disease activity are less well studied in Crohn's disease, but are gaining attention. Current published treatment algorithms in inflammatory bowel disease do not take into consideration histologic activity; however, this may change in the near future. In order for histologic measurements to be included in clinical decision-making, validated, reliable, and responsive histologic scoring systems are needed. In this review, the recent literature on the significance of histologic activity in both ulcerative colitis and Crohn's disease is summarized. Histologic scoring systems are also briefly discussed.

Visceral adiposity predicts post-operative Crohn's disease recurrence

BACKGROUND

Excessive visceral adipose tissue has been associated with poorer outcomes in patients with inflammatory bowel disease.

AIM

To determine whether body composition is associated with outcome in a prospective study of post-operative Crohn's disease patients.

METHODS

The POCER study evaluated management strategies for prevention of post-operative Crohn's disease recurrence; subjects were enrolled after resection of all macroscopic Crohn's disease and were randomised to early endoscopy and possible treatment escalation, or standard care. The primary endpoint was endoscopic recurrence at 18 months. 44 subjects with cross-sectional abdominal imaging were studied, and body composition analysis performed using established techniques to measure visceral adipose tissue area, subcutaneous adipose tissue area, and skeletal muscle area.

RESULTS

The body composition parameter with the greatest variance was visceral adipose tissue. Regardless of treatment, all subjects with visceral adipose tissue/height² >1.5 times the gender-specific mean experienced endoscopic recurrence at 18 months (compared to 47%) [relative risk 2.1, 95% CI 1.5-3.0, P = 0.012]. Waist circumference correlated strongly with visceral adipose tissue area (ρ = 0.840, P < 0.001). Low skeletal muscle was prevalent (41% of patients), but did not predict endoscopic recurrence; however, appendicular skeletal muscle indices correlated inversely with faecal calprotectin (ρ = 0.560, P = 0.046).

CONCLUSIONS

Visceral adiposity is an independent risk factor for endoscopic recurrence of Crohn's disease after surgery. Sarcopenia correlates with inflammatory biomarkers. Measures of visceral adipose tissue may help to stratify risk in post-operative management strategies.

Submucosal Plexitis as a Predictive Factor for Postoperative Endoscopic Recurrence in Patients with Crohn's Disease Undergoing a Resection with Ileocolonic Anastomosis: Results from a Prospective Single-centre Study

AIM

Ileocolonoscopy allows early detection of recurrence after surgical resection for Crohn's disease [CD]. Plexitis, defined as presence of inflammatory cells in or around enteric ganglia or nerve bundles, in the proximal surgical margin has been associated with an increased overall recurrence risk. We investigated prospectively whether plexitis can predict endoscopic recurrence [ER] in a consecutive cohort of CD patients undergoing ileocolonic resection.

METHODS

All CD patients undergoing ileocolonic resection in our institution between October 2009 and December 2012 were eligible for this study. Clinical data were obtained prospectively from the patients' files, and biopsies from the proximal surgical margins were analysed immunohistochemically for inflammation at the myenteric and submucosal plexus [lymphocytes, mast cells, eosinophils]. The degree of plexitis was correlated with the presence of ER at 6 months, defined as a modified Rutgeerts' score of ≥ i2b. Multivariate models were developed and tested to predict posterior probability of ER.

RESULTS

A total of 74 patients were included. Six months after ileocolonic resection, 50% showed ER. Known risk factors such as penetrating disease, previous resections, and active smoking, showed no relation with ER. On the other hand, submucosal lymphocytic plexitis was associated with ER [p = 0.020]. The predictive value of lymphocytic cell count increased with more extensive biopsy sampling and with application of immunohistochemistry.

CONCLUSIONS

Submucosal lymphocytic plexitis in the proximal surgical margin was significantly related with a higher risk for ER after ileocolonic resection. These data support development of a postoperative prevention trial with vedolizumab, which may block lymphocytic trafficking in the postoperative bowel.

Fecal calprotectin in the prediction of postoperative recurrence of Crohn's disease in children and adolescents

BACKGROUND

Fecal calprotectin (FC) correlates with endoscopic recurrence of Crohn's disease (CD) in adults but has not been studied among children postoperatively. We aimed to analyze whether FC relates with postoperative CD recurrence in children.

METHODS

Altogether 51 postoperative endoscopies and FC measurements from 22 patients having undergone surgery for CD at age ≤18years were included.

RESULTS

Ileocecal resection (n=15), small bowel resection (n=6), or left hemicolectomy (n=1) was performed at median age of 15.1 (interquartile range 14.4-17.6) years. Following surgery, FC decreased significantly (659 vs. 103μg/g, p=0.001). During median follow-up of 5.7 (4.2-7.7) years, either endoscopic or histological recurrence occurred in 17 patients (77%). FC >139μg/g at time of endoscopy or FC increase of 79μg/g compared to first postoperative value was suggestive of endoscopic recurrence (Rutgeerts score i2-i4), while FC >101μg/g or increase of 21μg/g indicated histological recurrence. Best accuracy for prediction of recurrence was obtained by combining FC at endoscopy and the postoperative increase of FC. The corresponding AUROC values were 0.74 (95% 0.58-0.89) for endoscopic recurrence whereas 0.81 (95% CI 0.67-0.95) for histological recurrence.

CONCLUSION

FC is a useful surrogate marker of postoperative recurrence also in pediatric CD patients.

Optimal delivery of follow-up care after surgery for Crohn's disease: current perspectives

Despite improvements in medical therapies for Crohn’s disease (CD), up to 70% of patients require surgery within 10 years of diagnosis. Surgery is not curative, and almost all patients will experience endoscopic recurrence, and many will go on to clinical recurrence. Identifying patients at high-risk of endoscopic recurrence and standardizing postoperative assessments are essential in preventing clinical recurrence of CD. In this review, we discuss the assessment, monitoring, and treatment of postoperative CD patients. We address the various individual risk factors as well as composite risk factors. Medications used for primary CD treatment can be used in the postoperative setting to prevent endoscopic or clinical recurrence with varying efficacy, although the cost-effectiveness of these approaches are not fully understood. Future directions for postoperative CD management include evaluation of newer biologic agents such as anti-integrin therapy and fecal microbiota transplant for prevention of recurrence. Development of a standard preoperative risk assessment tool to clearly stratify those at high-risk of recurrence is necessary to guide empiric therapy. Lastly, the incorporation of noninvasive testing into disease monitoring will likely lead to early detection of endoscopic recurrence that will allow for tailored treatment to prevent clinical recurrence.

Myenteric plexitis is a risk factor for endoscopic and clinical postoperative recurrence after ileocolonic resection in Crohn's disease

BACKGROUND

As surgical resection is not curative in Crohn's disease, postoperative recurrence remains a crucial issue. The selection of patients, according to available risk factors, remains disappointing in clinical practice highlighting the need for better criteria, such as histologic features.

AIMS

To investigate whether submucosal and myenteric plexitis increase the risk of endoscopic, clinical and surgical postoperative recurrence in Crohn's disease.

METHODS

From the pathology department database, we retrospectively retrieved the data of all the patients who have undergone ileocolonic resection for Crohn's disease. Two pathologists, blinded from clinical data, reviewed all specimens to evaluate the presence of plexitis at the proximal resection margin.

RESULTS

Of the 75 included CD patients, 19 (25.3%) had histological involvement of resection margin. Inflammatory cells count for myenteric and submucosal plexus were performed in 56 patients. In multivariate analysis, the myenteric plexitis was a risk factor for endoscopic postoperative recurrence (HR 8.83 CI95% [1.6-48.6], p=0.012), and the presence of at least one myenteric lymphocyte (HR 4.02 CI95% [1.4-11.2], p=0.008) was predictive of clinical postoperative recurrence. We observed no histologic predictor for surgical postoperative recurrence.

CONCLUSION

Myenteric plexitis in proximal margins of ileocolonic resection specimens is independently associated with endoscopic and clinical postoperative recurrence in Crohn's disease.

Endoscopy-based management decreases the risk of postoperative recurrences in Crohn’s disease

AIM: To investigate whether an endoscopy-based management could prevent the long-term risk of postoperative recurrence.

METHODS: From the pathology department database, we retrospectively retrieved the data of all the patients operated on for Crohn’s disease (CD) in our center (1986-2015). Endoscopy-based management was defined as systematic postoperative colonoscopy (median time after surgery = 9.5 mo) in patients with no clinical postoperative recurrence at the time of endoscopy.

RESULTS: From 205 patients who underwent surgery, 161 patients (follow-up > 6 mo) were included. Endoscopic postoperative recurrence occurred in 67.6%, 79.7%, and 95.5% of the patients, respectively 5, 10 and 20 years after surgery. The rate of clinical postoperative recurrence was 61.4%, 75.9%, and 92.5% at 5, 10 and 20 years, respectively. The rate of surgical postoperative recurrence was 19.0%, 38.9% and 64.7%, respectively, 5, 10 and 20 years after surgery. In multivariate analysis, previous intestinal resection, prior exposure to anti-TNF therapy before surgery, and fistulizing phenotype (B3) were postoperative risk factors. Previous perianal abscess/fistula (other perianal lesions excluded), were predictive of only symptomatic recurrence. In multivariate analysis, an endoscopy-based management (n = 49/161) prevented clinical (HR = 0.4, 95%CI: 0.25-0.66, P < 0.001) and surgical postoperative recurrence (HR = 0.30, 95%CI: 0.13-0.70, P = 0.006).

CONCLUSION: Endoscopy-based management should be recommended in all CD patients within the first year after surgery as it highly decreases the long-term risk of clinical recurrence and reoperation.

Outcome of Surgery for Coloduodenal Fistula in Crohn's Disease

BACKGROUND

This study was conducted to report the short- and long-term outcomes of surgery for coloduodenal fistula in Crohn's disease and explore the effect of preoperative optimization on surgical outcome.

METHODS

This is a retrospective review of 34 patients with coloduodenal fistula complicating Crohn's disease between Jan 2008 and May 2015. Demographic information, preoperative management, and intraoperative and postoperative outcome data were collected.

RESULTS

Primary duodenal repair was carried out in 33 patients (13 with duodenal defect >3 cm), and bypass surgery was performed in one patient with duodenal stenosis. Patients undergoing preoperative optimization (n = 25) had decreased postoperative major (24.0 vs. 87.5 %, P = 0.005) and intra-abdominal septic (20.0 vs. 75.0 %, P = 0.008) complications compared to patients with emergent/semi-emergent surgery (n = 8). No duodenal stenosis occurred on a median follow-up of 22.5 months. Patients with duodenum-ileocolic anastomosis fistula had longer postoperative stay (14.0 vs. 10.0 days, P = 0.032) and increased possibility of refistulization of the duodenum on follow-up (30.0 vs. 0 %, P = 0.031) compared with those with spontaneous duodenum-colonic fistula.

CONCLUSION

Primary duodenal repair can be safely performed in coloduodenal fistula in Crohn's disease provided there was no duodenal stenosis, even for large duodenal defects. Preoperative optimization is associated with reduced postoperative complications. Patients with duodenum-ileocolic anastomosis fistula are more likely to have duodenum fistula recurrence compared to those with spontaneous duodenum-colonic fistula.

Kono-S Anastomosis for Surgical Prophylaxis of Anastomotic Recurrence in Crohn's Disease: an International Multicenter Study

INTRODUCTION

The Kono-S (antimesenteric functional end-to-end handsewn) anastomosis has been used for Crohn's disease in Japan and the USA since 2003 and 2010, respectively. This technique was designed to reduce the risk of anastomotic surgical recurrence. This study reviews the outcomes a decade after the introduction of the Kono-S anastomosis to clinical practice.

METHODS

This study was conducted at five hospitals (four in Japan and one in the USA). A total of 187 patients in Japan (144 patients, group J) and the USA (43 patients, group US) who underwent Kono-S anastomosis for Crohn's disease between September 2003 and September 2011 were included.

RESULTS

With a median follow-up of 65 months, two surgical anastomotic recurrences have occurred in group J. Kaplan-Meier analysis showed that 5 and 10 years surgical recurrence-free survival rate was 98.6% in group J. No surgical anastomotic recurrences have been detected in group US with a median follow-up of 32 months. The Kono-S anastomosis was technically feasible and performed in all patients.

CONCLUSION

The Kono-S anastomosis appears to be safe and effective in reducing the risk of surgical recurrence in Crohn's disease.

How to predict clinical relapse in inflammatory bowel disease patients

Inflammatory bowel diseases have a natural course characterized by alternating periods of remission and relapse. Disease flares occur in a random way and are currently unpredictable for the most part. Predictors of benign or unfavourable clinical course are required to facilitate treatment decisions and to avoid overtreatment. The present article provides a literature review of the current evidence on the main clinical, genetic, endoscopic, histologic, serologic and fecal markers to predict aggressiveness of inflammatory bowel disease and discuss their prognostic role, both in Crohn’s disease and ulcerative colitis. No single marker seems to be reliable alone as a flare predictor, even in light of promising evidence regarding the role of fecal markers, in particular fecal calprotectin, which has reported good results recently. In order to improve our daily clinical practice, validated prognostic scores should be elaborated, integrating clinical and biological markers of prognosis. Finally, we propose an algorithm considering clinical history and biological markers to intercept patients with high risk of clinical relapse.

Presence of Granulomas in Mesenteric Lymph Nodes Is Associated with Postoperative Recurrence in Crohn's Disease

BACKGROUND

The association between the presence of granulomas in the mesenteric lymph node (MLN) and postoperative recurrent Crohn's disease (CD) is unknown. Our aim was to assess the predictive value of the presence of granulomas in MLN as well as in bowel wall for postoperative recurrence of CD.

METHODS

Patients with CD who underwent the index ileocolonic resection between 2004 and 2012 were included. Surgical pathology reports were reviewed for the presence and location of granulomas. The status of MLN granulomas was confirmed by re-review of surgical pathology specimen from randomly sampled patients by an expert pathologist. Both univariable and multivariable analyses were performed to assess the risk factors associated with postoperative recurrent CD.

RESULTS

A total of 194 patients were included. Granulomas were detected in the MLN in 23 patients (11.9%), and in the intestinal wall in 57 (29.4%). On Kaplan-Meier curve, the presence of granulomas in MLN was found to be a risk factor for postoperative endoscopic recurrence (P = 0.015) as well as surgical recurrence (P = 0.035). In contrast, granulomas in the bowel wall, which was not found to be associated with neither endoscopic recurrence (P = 0.94) or surgical recurrence (P = 0.56). On Cox proportional hazards regression analysis, the presence of MLN granulomas was independently associated with an increased risk for both postoperative endoscopic recurrence (hazard ratio [HR] = 1.91; 95% confidence interval [CI], 1.06-3.45; P = 0.031) and surgical recurrence (HR = 3.43; 95% CI, 1.18-9.99; P = 0.023).

CONCLUSIONS

The presence of granulomas in MLN but not in intestine per se was found to be an independent risk factor for recurrence in CD patients undergoing ileocolonic resection.