Both preoperative perinuclear antineutrophil cytoplasmic antibody and anti-CBir1 expression in ulcerative colitis patients influence pouchitis development after ileal pouch-anal anastomosis

The aetiology of pouchitis in patients with inflammatory bowel disease

Restorative proctocolectomy with ileal pouch-anal anastomosis is a treatment option for patients with refractory ulcerative colitis. Pouchitis is the most common complication, representing a spectrum of diseases ranging from acute antibiotic-responsive type to chronic antibiotic-refractory. Early accurate diagnosis using a combined assessment of symptoms, endoscopy and histology is important for both treatment and prognostication. Most patients respond well to antibiotic therapy; however, management of chronic antibiotic-refractory pouchitis remains a challenge, and treatment options are based on small studies. Pouchitis is thought to be driven by the interaction between genetics, the immune system and the environment but as yet a causal relationship has yet to be identified. Further longitudinal assessment of the pouch integrating new technologies may help us understand the factors driving pouchitis. This review outlines the currently understood risk factors and aetiology of pouchitis.

Shedding New Light on High-Risk Phenotypes for Pouchitis

Identifying those patients at the greatest risk for pouchitis at the time of ileal pouch-anal anastomosis for ulcerative colitis remains a challenge. We discuss the importance of this topic by reviewing recent data regarding the impact of acute severe ulcerative colitis on risk of pouchitis and the implications for future clinical decisions and studies of risk stratification.

Prognostic modelling in IBD

In the ideal world prognostication or predicting disease course in any chronic condition would allow the clinician to anticipate disease behaviour, providing crucial information for the patient and data regarding best use of resources. Prognostication also allows an understanding of likely response to treatment and the risk of adverse effects of a treatment leading to withdrawal in any individual patient. Therefore, the ability to predict outcomes from the onset of disease is the key step to developing precision personalised medicine, which is the design of medical care to optimise efficiency or therapeutic benefit based on careful profiling of patients. An important corollary is to prevent unnecessary healthcare costs. This paper outlines currently available predictors of disease outcome in IBD and looks to the future which will involve the use of artificial intelligence to interrogate big data derived from various important 'omes' to tease out a more holistic approach to IBD.

Associations between Pouchitis and Fecal Calprotectin after Restorative Proctocolectomy in Patients with Ulcerative Colitis

Introduction

Recently, fecal calprotectin has been identified and used as an assessment tool for the confirmation of disease activity in ulcerative colitis. Although a meta-analysis suggested the usefulness of fecal calprotectin for the assessment of pouchitis, the number of participants was still insufficient. Therefore, we prospectively measured fecal calprotectin levels during pouchoscopy and analyzed their associations with pouchitis.

Methods

Patients who underwent pouchoscopy after total proctocolectomy and ileal pouch-anal anastomosis for ulcerative colitis were included. Fecal samples were collected for the measurement of calprotectin during pouchoscopy. Patients either with or without suspicious pouchitis were included. Pouchitis was defined as a modified pouchitis disease activity index (m-PDAI) score of ≥5. The associations between the development of pouchitis and the m-PDAI score and fecal calprotectin and serum markers, including C-related protein, albumin, and white blood cells, were assessed.

Results

A total of 170 patients were included. Seventy-two patients were diagnosed with pouchitis with an m-PDAI score of 7.3 ± 1.5. The values of fecal calprotectin were 1,500 ± 1,544 μg/g in patients with pouchitis and 259 ± 402 μg/g in patients without pouchitis (p < 0.01). The correlation coefficient between calprotectin and the m-PDAI score was significant (r2 = 0.279, p < 0.001). The cutoff value of fecal calprotectin in receiver operating characteristic analysis was 246 μg/g (area under curve 0.85, sensitivity 83.9%, specificity 71.0%). Fecal samples were able to be collected from 6 patients. The levels of fecal calprotectin significantly decreased from 2,101.3 ± 880.3 μg/g to 284.2 ± 96.9 μg/g in response to the treatment.

Conclusions

Elevated fecal calprotectin appeared to be significantly correlated with pouchitis. We should consider the alteration of this marker during treatments in further studies.

Increasing Incidence of Pouchitis Between 1996 and 2018: A Population-Based Danish Cohort Study

BACKGROUND & AIMS

Current knowledge regarding the epidemiology of pouchitis is based on highly selected, mostly single-center, patient cohorts. Our objective was to prospectively determine the population-based incidence of pouchitis in patients with ulcerative colitis in the first 2 years after ileal pouch-anal anastomosis and analyze time trends of the incidence of pouchitis.

METHODS

Using national registries, we established a population-based cohort of all Danish patients undergoing proctocolectomy with ileal pouch-anal anastomosis for ulcerative colitis between 1996 and 2018. The primary outcome was the development of pouchitis within the first 2 years after surgery, evaluated by time period. We used Kaplan-Meier and Cox proportional hazard modeling to evaluate the time to development of pouchitis.

RESULTS

Overall, 1664 patients underwent an ileal pouch-anal anastomosis. The cumulative incidence of pouchitis in the 2 years after ileal pouch-anal anastomosis increased throughout the study period, from 40% in the period from 1996 to 2000 (95% CI, 35%-46%) to 55% in the period from 2015 to 2018 (95% CI, 48%-63%). Patients undergoing surgery between 2015 and 2018 also showed an increased risk of pouchitis compared with the earliest study period (1996-2000) after adjusting for sex, age, and socioeconomic status (hazard ratio, 1.57; 95% CI, 1.20-2.05).

CONCLUSIONS

This population-based study showed a 15% absolute and 38% relative increase in the incidence of pouchitis among patients undergoing surgery between 1996 and 2018, with the greatest cumulative incidence of pouchitis shown in the most recent era (2015-2018). The striking increase in the incidence of pouchitis highlights the need for further research into causes and prevention of pouchitis.

Histologic Activity in an Endoscopically Normal-Appearing Pouch Predicts Future Risk of Pouchitis in Patients With Ulcerative Colitis

INTRODUCTION

The impact of histologic inflammation on subsequent risk of acute pouchitis in patients with ulcerative colitis (UC) has not been robustly examined.

METHODS

We examined the association between histologic inflammation in endoscopically normal-appearing ileal pouches in patients with UC with subsequent risk of antibiotic-responsive acute pouchitis.

RESULTS

Among 163 study patients, 53% had histologic inflammation in an endoscopically normal-appearing ileal pouch. Histologic inflammation in the pouch was associated with an increased risk of pouchitis (24.1% vs 6.8%, adjusted odds ratio 4.41, 95% confidence interval 1.48-13.20).

DISCUSSION

Histologic inflammation in an endoscopically normal pouch was associated with an increased risk of acute pouchitis.

Disease Monitoring of the Ileoanal Pouch: How to Utilize Biomarkers, Imaging, and Pouchoscopy

PURPOSE OF REVIEW

Restorative proctocolectomy with ileal pouch-anal anastomosis for ulcerative colitis has been associated with multiple short- and long-term complications. In this review, we examine the role of biomarkers, imaging, and pouchoscopy in the assessment of patients after ileal pouch-anal anastomosis, with a particular focus on the emergence of novel biomarkers and techniques for evaluating and risk stratifying patients after this procedure in the hopes of improving outcomes in this specific population.

RECENT FINDINGS

There are indications that that the incidence of pouchitis may be increasing in recent decades. Calprotectin and other non-invasive imaging tests such as ultrasound may offer advantages in distinguishing patients with inflammatory conditions of the pouch from other etiologies. In the search for other biomarkers that may identify patients at risk for inflammatory conditions of the pouch, the stool microbiota and metabolomics may play a key role in identifying those patients at greatest risk for complications. Advances in biomarkers, imaging, and standardized pouchoscopy scoring offer immediate improvements in clinical care and will prompt future research efforts.

Management of refractory inflammatory bowel disease

PURPOSE OF REVIEW

Nearly one-third of patients with inflammatory bowel disease (IBD) do not achieve remission despite our best therapies. When this happens, it is critical to understand the reason for treatment failure. Once nonresponse is confirmed, these patients should be referred to an IBD centre for multidisciplinary care. This review will discuss the remaining treatment options, including escalation of biologics to unlicensed doses, combination biologics, nonvalidated therapies and surgical options. It will additionally provide updates in the management of acute severe ulcerative colitis (ASUC).

RECENT FINDINGS

There is an increasing interest in combination biologics to treat refractory IBD, although data supporting its safety and effectiveness are limited. The use of hyperbaric oxygen, mesenchymal stem cell therapy and dietary interventions also show early promise in this area. Studies have additionally focused on personalized therapy to identify aggressive phenotypes and predict treatment response in these challenging patients. In ASUC, infliximab and cyclosporine remain mainstays of treatment, and tofacitinib shows promise as a salvage therapy.

SUMMARY

Refractory IBD is common, yet large knowledge gaps remain. Recent and ongoing studies have focused on medical, surgical and dietary approaches with mixed success. Larger prospective studies are desperately needed to address this complex issue.

Tools for the Diagnosis and Management of Crohn's Disease

Numerous tools have emerged over recent decades to aid in the increasingly complex management of patients with Crohn's disease (CD) beyond endoscopy, including video capsule endoscopy, magnetic resonance enterography, computed tomography enterography, a variety of biomarkers, and even wearable biosensors and smartphone applications. These tools have allowed for a more sophisticated and less invasive complementary approach to the evaluation of disease activity and treatment response in patients with CD. This article details the characteristics, practical application, and limitations of these various modalities and discusses how updated guidelines are now incorporating many of them into a treat-to-target strategy.

Association Between Portal Vein Thrombosis and Pouchitis in Patients with Ulcerative Colitis

BACKGROUND

Pouchitis is the most common long-term complication in patients requiring colectomy ileal pouch-anal anastomosis with medically refractory ulcerative colitis or colitis-associated neoplasia. A previous small case series suggests associated between portal vein thrombosis (PVT) and ischemic pouchitis.

AIM

To evaluate the association between PVT and other demographic and clinical factors and pouchitis.

METHODS

We used Explorys Inc., a population-based database, to search medical records between 1999 and 2020 with SNOMED-CT code criteria for "construction of pouch" and "ileal pouchitis." Patients with pouchitis were compared to those with previous pouch construction without pouchitis. Factors associated with pouchitis identified with univariable analysis were introduced into a multivariable model. A post hoc analysis further stratified demographical findings of the association between PVT and pouchitis.

RESULTS

We identified 7900 patients with ileal pouchitis (7.5%) and 97,510 with pouch construction without pouchitis. In multivariate binary logistic regression, adjusted odds ratio (aOR) for the risk of pouchitis in patients with PVT was 10.78 (95% confidence interval [CI] 7.04-16.49, P < 0.001). Other significant factors associated with pouchitis included male gender (aOR 1.11, 95% CI 1.02-1.21, P = 0.018), deep vein thrombosis (aOR 1.46, 95% CI 1.23-1.72, P < 0.001), and the use of non-steroidal anti-inflammatory drugs (aOR 1.37, 95% CI 1.28-1.45, P < 0.001). Smoking was a protective factor (aOR 0.30, 95% CI 0.33-0.36, P < 0.001). Further sub-analysis showed a higher prevalence of younger patients with PVT and pouchitis.

CONCLUSIONS

We report PVT as an independent risk factor associated with pouchitis. Our findings support that PVT is a potentially manageable perioperative complication, and intervention may reduce the risk of pouchitis.

Computational Learning of microRNA-Based Prediction of Pouchitis Outcome After Restorative Proctocolectomy in Patients With Ulcerative Colitis

BACKGROUND

Ileal pouch-anal anastomosis (IPAA) is the standard of care after total proctocolectomy for ulcerative colitis (UC). However, inflammation often develops in the pouch, leading to acute or recurrent/chronic pouchitis (R/CP). MicroRNAs (miRNA) are used as accurate diagnostic and predictive biomarkers in many human diseases, including inflammatory bowel diseases. Therefore, we aimed to identify an miRNA-based biomarker to predict the occurrence of R/CP in patients with UC after colectomy and IPAA.

METHODS

We conducted a retrospective study in 3 tertiary centers in France. We included patients with UC who had undergone IPAA with or without subsequent R/CP. Paraffin-embedded biopsies collected from the terminal ileum during the proctocolectomy procedure were used for microarray analysis of miRNA expression profiles. Deep neural network-based classifiers were used to identify biomarkers predicting R/CP using miRNA expression and relevant biological and clinical factors in a discovery cohort of 29 patients. The classification algorithm was tested in an independent validation cohort of 28 patients.

RESULTS

A combination of 11 miRNA expression profiles and 3 biological/clinical factors predicted the outcome of R/CP with 88% accuracy (area under the curve = 0.94) in the discovery cohort. The performance of the classification algorithm was confirmed in the validation cohort with 88% accuracy (area under the curve = 0.90). Apoptosis, cytoskeletal regulation by Rho GTPase, and fibroblast growth factor signaling were the most dysregulated targets of the 11 selected miRNAs.

CONCLUSIONS

We developed and validated a computational miRNA-based algorithm for accurately predicting R/CP in patients with UC after IPAA.

Incidence, Risk Factors, and Outcomes of Pouchitis and Pouch-Related Complications in Patients With Ulcerative Colitis

BACKGROUND & AIMS

Acute pouchitis is the most common non-surgical complication after restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC). We used validated case-finding definitions for pouchitis to search administrative claims data and determine the incidence of pouchitis in the first 2 years after IPAA.

METHODS

We identified all patients who underwent proctocolectomy with IPAA for UC in the IQVIA Legacy PharMetrics Adjudicated Claims Database, from January 1, 2007 through June 1, 2016. The primary outcome was the development of pouchitis within 2 years after IPAA. Secondary outcomes included isolated acute vs recurrent pouchitis, immunosuppressive therapy, further surgery, and admission to the hospital.

RESULTS

Among 594 patients, the cumulative incidence of pouchitis within 2 years of IPAA was 48% (95% CI, 44%-52%). The cumulative incidence of isolated acute pouchitis was 29% (95% CI, 26%-33%). Compared to patients with isolated acute pouchitis, patients who received a diagnosis of recurrent pouchitis (cumulative incidence, 19%: 95% CI, 16%-22%) demonstrated increased outpatient visits, emergency department visits, and inpatient admissions (all P < .001). Patients who developed pouchitis were more likely to have a history of primary sclerosing cholangitis (adjusted odds ratio [aOR], 3.94; 95% CI, 1.05-14.8) and anti-tumor necrosis factor alpha therapy prior to colectomy (aOR 1.63; 95% CI, 1.09-2.45). Among patients with pouchitis, the cumulative frequency of new immunosuppressive therapy was 40% (95% CI, 35%-46%) and the cumulative incidence of pouch excision was 1.0% (95% CI, 0.4%-3.0%). The cumulative incidence of a new diagnosis of Crohn's disease after IPAA for UC was 9.0% (95% CI, 7.2%-11%).

CONCLUSIONS

In a geographically diverse population, 48% of patients with UC developed pouchitis within the first 2 years after IPAA. Patients with pouchitis had greater use of healthcare resources, indicating a significant burden of disease.

Improving prediction of disease outcome for inflammatory bowel disease: progress through systems medicine

Introduction: Inflammatory bowel diseases (IBDs) are lifelong conditions causing relapsing inflammation of the intestine. In the absence of a cure, clinical management of IBDs is extremely challenging since they present with a wide range of phenotypes and disease behaviors. Hence, there is an urgent need for markers that could guide physicians in making the right choice of the rapidly growing treatment options toward a personalized care that could improve the overall outcome.Areas covered: In this review, the authors summarize existing biomarkers in IBD, discuss the challenges with the development of prognostic biomarkers and propose alternative options such as focusing on the prediction of the response to individual treatments, i.e. predictive biomarkers. The problems related to developing disease prognostic and predictive biomarkers in the field of IBDs are discussed including the difficulties in dealing with phenotypic heterogeneity particularly when performing studies in a real-life setting. The authors reviewed literature from PubMed.Expert opinion: Systems biology provides potential solutions to this problem by offering an unbiased, holistic approach to adjusting for variation in larger datasets thereby increasing the chances of identifying true associations between molecular profiles and clinical phenotypes.

Disease and Treatment Patterns Among Patients With Pouch-related Conditions in a Cohort of Large Tertiary Care Inflammatory Bowel Disease Centers in the United States

BACKGROUND

Gaps exist in our understanding of the clinical course of pouch-related disorders.

METHODS

We evaluated baseline disease activity and longitudinal treatment patterns among patients with inflammatory conditions of the pouch.

RESULTS

Among 468 patients with an ileal pouch-anal anastomosis (IPAA), 94 (20%) had acute pouchitis, 96 (21%) had chronic pouchitis, and 192 (41%) had Crohn disease of the pouch. Following an IPAA, 38% of patients were treated with a biologic and 11% underwent inflammatory bowel disease- or bowel-related surgery.

CONCLUSIONS

Treatment patterns after IPAA indicate that pouch-related disorders have a significant impact on individual patients and the healthcare system.

Prognostic value of peri-nuclear Anti Neutrophil Cytoplasmic Antibodies in subjects with primary sclerosing cholangitis

OBJECTIVE

To evaluate the prognostic value of peri-nuclear Anti- Neutrophil Cytoplasmic Antibodies (p-ANCA) in subjects with primary sclerosing cholangitis (PSC) and in particular whether it is associated with inflammatory bowel disease (IBD).

PATIENTS AND METHODS

In the last 9 years,64 patientswere admitted to our Hospital with PSC: 34 males, mean age 53 years, range 17-90. All the patients had a cholestatic pattern of elevated serum enzymes. The diagnosis was made in most cases with magnetic resonance and in small percentages with endoscopic retrograde cholangiopancreatography (ERCP) or liver biopsy. In 33 patients with PSC, colonoscopy and p-ANCA assays were possible.

RESULTS

Thirteen patients showed p-ANCA positivity: 8 had ulcerative colitis (UC), with associated colon cancer (CC) in 3 cases, 3 had Crohn's disease (CD), 2 had no inflammatory bowel disease (IBD). Twenty patients were p-ANCA negative: only 1 with indeterminate IBD, while 19 had no IBD.

CONCLUSIONS

IBD, or especially UC, is present in85% of patients with CSP and p-ANCA positivity, whereas 95% of patients with PSC who test negative for p- ANCA do not have IBD.

Pouchitis in pediatric ulcerative colitis: A multicenter study on behalf of Italian Society of Pediatric Gastroenterology, Hepatology and Nutrition

BACKGROUND

Data on the epidemiology and risk factors for pouchitis following restorative proctocolectomy and ileal pouch-anal anastomosis (IPAA) in pediatric patients with ulcerative colitis (UC) are scarce.

AIMS

To determine incidence, risk factors and clinical outcome of pouchitis following IPAA in children.

METHODS

This multicenter, retrospective cohort study, included all pediatric UC patients who underwent colectomy and IPAA from January 2010 to December 2016.

RESULTS

Eighty-five patients were enrolled. During a median post-surgical period of 24.8 (range: 1.0-72.0) months following IPAA, 38 (44.7%) patients developed pouchitis, including 6 (15.8%) who developed chronic pouchitis. Kaplan-Meier survival estimates of the cumulative probability for pouchitis were 14.6% at 1 year and 27.3% and 51.5% at 2 and 5 years, respectively. Multiple Cox regression model showed that older age at colectomy (hazard ratio, HR: 0.89, p = 0.008) was a protective factor, whereas chronic active colitis as indication for surgery (HR: 4.45, p < 0.001), and a 3-stage IPAA (HR: 2.86, p = 0.028) increased the risk for pouchitis.

CONCLUSIONS

Long-term risk for pouchitis is significantly high in pediatric-onset UC after IPAA. Younger age at colectomy, chronic active colitis as indication for surgery and 3-stage IPAA may increase the risk for pouchitis.

Recommendations of the Spanish Working Group on Crohn's Disease and Ulcerative Colitis (GETECCU) on pouchitis in ulcerative colitis. Part 1: Epidemiology, diagnosis and prognosis

Pouchitis is a common complication in ulcerative colitis patients after total proctocolectomy. This is an unspecific inflammation of the ileo-anal pouch, the aetiology of which is not fully known. This inflammation induces the onset of symptoms such as urgency, diarrhoea, rectal bleeding and abdominal pain. Many patients suffering from pouchitis have a lower quality of life. In addition to symptoms, an endoscopy with biopsies is mandatory in order to establish a definite diagnosis. The recommended index to assess its activity is the Pouchitis Disease Activity Index (PDAI), but its modified version (PDAIm) can be used in clinical practice. In accordance with the duration of symptoms, pouchitis can be classified as acute (<4 weeks) or chronic (>4 weeks), and, regarding its course, pouchitis can be infrequent (<4 episodes per year), recurrent (>4 episodes per year) or continuous.

Prognosticating the Course of Inflammatory Bowel Disease

Both Crohn's disease and ulcerative colitis are inflammatory bowel diseases (IBD) that can lead to progressive irreversible bowel damage. Selecting the most appropriate therapy for patients is a challenge because not all patients diagnosed with IBD have complications, and the amount of time to develop a complication is different for individuals. Models using patient characteristics, genetics, and immune responses help identify those patients who require early aggressive therapy with a goal to modify their disease course. Future research will help identify the role that the microbiome, metagenomics, metaproteomics, and microRNAs play in a patient prognosis.

Predictors for Pouchitis After Ileal Pouch-Anal Anastomosis for Pediatric-Onset Ulcerative Colitis

BACKGROUND

The predictive factors for the development of pouchitis after ileal pouch-anal anastomosis (IPAA) in pediatric-onset ulcerative colitis (UC) have not been well investigated. The present study aimed to determine the predictive factors for the development of pouchitis after IPAA in the pediatric UC population.

METHODS

The data from 54 patients with pediatric-onset UC who underwent IPAA in Mie University Hospital between 2000 and 2017 were retrospectively reviewed. A modified pouchitis disease activity index of ≥5 was defined as pouchitis. Potential preoperative, intraoperative, and postoperative predictors for pouchitis including various demographic and clinical variables were analyzed using Cox regression analysis, Students' t-tests, Mann-Whitney U tests, and Kaplan-Meier curves. The optimal cutoff value for continuous variables was determined using the receiver operating characteristic curve analysis.

RESULTS

Pouchitis was identified in 17 (31.5%) patients within 5 y of follow-up. In multivariable analysis, the independent predictors for pouchitis were preoperative cumulative steroid dose of >10,000 mg (P = 0.0056) and >65% neutrophils just before IPAA (P = 0.032). Multivariate analysis revealed that the independent predictors of pouchitis were a total steroid dose of >10,000 mg (P = 0.0002) and a neutrophil percentage of >65% (P = 0.0078). No patient for whom both of these independent predictors were negative developed pouchitis, whereas >40% of patients who had one or both predictors developed pouchitis.

CONCLUSIONS

In pediatric patients with UC, the predictive factors for pouchitis development are a greater cumulative total dose of steroids and a greater percentage of neutrophils before IPAA.

Serological markers and inflammatory bowel disease: Prevalence of serum markers and their diagnostic value in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic nonspecific disease of the digestive tract that is caused by genetic and environmental factors, including ulcerative colitis, Crohn's disease, and unclassified IBD. At present, the diagnosis of IBD depends mainly on clinical manifestations, imaging changes, colonoscopy, and pathological biopsy, but there exist some limitations. The advantages of serological markers in IBD diagnosis are prominent, and a large number of relevant studies have been reported. This paper reviews the diagnostic and therapeutic value of serological markers in IBD, with an aim to clarify their role in the diagnosis and treatment of IBD.

Serological, genetic and clinical associations with increased health-care resource utilization in inflammatory bowel disease

OBJECTIVE

Inflammatory bowel diseases (IBD) are associated with significant morbidity and economic burden. The variable course of IBD creates a need for predictors of clinical outcomes and health resource utilization (HRU) to guide treatment decisions. We aimed to identify clinical, serological or genetic markers associated with inpatient resource utilization in patients with ulcerative colitis (UC) and Crohn's disease (CD).

METHODS

Patients with IBD with available genetic and serological data who had at least one emergency department visit or hospitalization in a 3-year period were included. The primary outcome measure was HRU, as measured by the All Patient Refined Diagnosis Related Group classification system. Univariate and multivariate linear and logistic regression models were used to identify the associations with HRU.

RESULTS

Altogether 858 (562 CD and 296 UC) patients were included. Anti-CBir1 seropositivity (P = 0.002, effect size [ES]: 0.762, 95% confidence interval [CI] 0.512-1.012) and low socioeconomic status (P = 0.005, ES: 1.620 [95% CI 1.091-2.149]) were independently associated with a high HRU. CD diagnosis (P = 0.006, ES: -0.701 [95% CI -0.959 to -0.443]) was independently associated with a low inpatient HRU.

CONCLUSION

In patients with IBD who required at least one emergency department visit or hospitalization, anti-CBir1 antibody status may be a useful biomarker of HRU when formulating management strategies to reduce disease complications and resource utilization.

IBD血清学标志物的临床应用前景

炎症性肠病(inflammatory bowel disease, IBD)是一种病因不明的慢性非特异性肠道炎症性疾病, 包括溃疡性结肠炎(ulcerative colitis, UC)和克罗恩病(Crohn's disease, CD). 目前IBD的诊断及临床过程主要依据其临床表现、常规检验、影像学特征、内镜所见及组织病理综合判断, 但远未满足临床实践. 因此, 寻找一种简单、准确的诊断方法成为目前亟待解决的问题. 迄今, IBD相关血清学标志物的应用对IBD的诊断与鉴别诊断、疾病严重程度界定、疗效判断和预后评估均凸显出其临床优势. 本文就近年来IBD血清学标志物的研究及其临床应用前景作一述评.

Review article: the pathogenesis of pouchitis

BACKGROUND

A total proctocolectomy followed by ileal pouch-anal anastomosis is a potentially curative surgery for ulcerative colitis or familial adenomatous polyposis. About 5-35% of patients with ulcerative colitis and 0-11% of patients with familial adenomatous polyposis develop subsequent inflammation of the ileal pouch termed pouchitis.

AIM

To provide a comprehensive analysis of the research studying the possible pathogenesis of pouchitis. The goals were to identify promising areas of investigation, to help focus clinicians, researchers and patients on how to better understand and then potentially manage ileal pouchitis, and to provide avenues for future research investigations.

METHODS

This review examined manuscripts from 1981 to 2015 that discussed and/or proposed hypotheses with supportive evidence for the potential underlying pathogenic mechanism for pouchitis.

RESULTS

The pathogenesis of pouchitis is not definitively understood, but various hypotheses have been proposed, including (i) recurrence of ulcerative colitis, (ii) dysbiosis of the ileal pouch microbiota, (iii) deprivation of nutritional short-chain fatty acids, (iv) mucosal ischaemia and oxygen-free radical injury, (v) host genetic susceptibility and (vi) immune dysregulation. However, none of these alone are able to fully explain pouchitis pathogenesis.

CONCLUSIONS

Pouchitis, similar to inflammatory bowel disease, is a complex disorder that is not caused by any one single factor. More likely, pouchitis occurs through a combination of both dysregulated host inflammatory mechanisms and interaction with luminal microbiota.

Predictors of Pouchitis After Ileal Pouch-Anal Anastomosis in Children

OBJECTIVES

Predictive factors for the development of pouchitis after ileal pouch-anal anastomosis (IPAA) in children have not been well studied. In this retrospective study, the incidence and risk factors that predict pouchitis in children with IPAA will be identified.

METHODS

The records of patients who underwent IPAA surgery at Children's Hospital of Wisconsin between January 2000 and December 2013 were reviewed retrospectively. Patients with clinical, endoscopic, and histological findings consistent with pouchitis were identified. The groups of patients with and without pouchitis or chronic pouchitis were compared to determine which demographic, pathological, or disease characteristics may serve as predictive factors for the development of pouchitis or chronic pouchitis.

RESULTS

Out of a total of 60 patients who underwent IPAA, preoperative diagnosis was ulcerative colitis (UC) in 43 and familial adenomatous polyposis (FAP) in 17. Pouchitis was identified in 24 (56%) patients with UC and 2 (12%) patients with FAP. Subgroup analysis of patients with UC revealed that chronic pouchitis occurred in 15 (35%) patients. The median follow-up period from construction of the IPAA was 35 months (range 4.59-104.26 months). The study analysis revealed that a higher Pediatric Ulcerative Colitis Activity Index score at the time of diagnosis was a significant predictive factor for both pouchitis (P = 0.001) and chronic pouchitis (P = 0.02).

CONCLUSIONS

Patients with UC and a higher PUCAI score at the time of diagnosis have a higher risk for developing pouchitis.

TNFRSF1B Is Associated with ANCA in IBD

The genetic basis of antineutrophil cytoplasmic antibody, an important biomarker of inflammatory bowel disease (IBD), has never been thoroughly examined on a genome-wide scale. In this study, we performed a 2-stage genome-wide association study (GWAS) on antineutrophil cytoplasmic antibody in IBD cases. In the 2959 IBD cases in the discovery stage, we observed an association between a variant in the gene TNFRSF1B with antineutrophil cytoplasmic antibody level (rs5745994, minor allele frequency = 0.028, beta = 18.12, 95% CI, 11.82-24.22, P = 1.89 × 10). This association was replicated in an independent cohort of 419 IBD cases (beta = 16.91, 95% CI, 6.13-27.69, P = 2.38 × 10). With a Q-value of 0.036, we performed a fixed-effect meta-analysis for the association of rs5745994 in both cohorts and observed a stronger association signal (beta = 17.81, 95% CI, 12.36-23.25, P = 8.97 × 10). TNFRSF1B gene codes for tumor necrosis factor (TNF) receptor 2 (TNFR2), thereby we examined the reported TNFRSF1B variant with serum TNFR2 level. We observed a negative association with serum TNFR2 level being 8.23 EU/mL in carriers and 9.12 EU/mL in noncarriers (P = 0.033). This finding indicates the functional role of identified TNFRSF1B variant in IBD serology and may be reflective of the underlying biological mechanisms that determine clinical expression and/or response to certain therapies.

Infliximab to Treat Refractory Inflammation After Pelvic Pouch Surgery for Ulcerative Colitis

BACKGROUND

Inflammatory pouch complications refractory to first-line therapies remain problematic following ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC). We evaluated infliximab efficacy and associations with therapeutic response.

METHODS

Data from individuals who underwent colectomy and IPAA for UC (2000-2014) were reviewed. Patients with chronic refractory pouchitis (CP) and Crohn's disease (CD)-like outcomes treated with infliximab were included. Pre-treatment parameters and response at median 8 (initial) and 48 weeks (sustained) were measured. Complete response was defined as symptomatic and endoscopic resolution with modified Pouchitis Disease Activity Index (mPDAI) <5. Partial response included mPDAI improvement >2. Serum was analysed for Anti-Saccharomyces cerevisiae antibodies (ASCA), anti-OmpC, anti-CBir1 and perinuclear Anti-Neutrophil Cytoplasmic Antibodies (pANCA).

RESULTS

One hundred and fifty-two patients with CP or a CD-like phenotype were identified. Forty-two were treated with infliximab (33% male; age 32.6±2.6 years, 28.5% CD-like). Post-induction response was achieved in 74% (48% complete) and sustained response in 62.6% (29.6% complete). Mean mPDAI and C-reactive protein declined from 8.5±0.3 to 2±3.4 (p < 0.002) and from 29.48±6.2 to 5.76±1.6mg/L (p < 0.001), respectively. Female gender, smoking and presence of anti-CBir1 were associated with infliximab use (p < 0.01) but not response. Pre-treatment mPDAI <10 (p < 0.01), resolution of rectal bleeding (p < 0.001 ) and week 8 endoscopic activity were associated with sustained response (p = 0.04; odds ratio [OR] 2.2; 95% confidence interval [CI] 1.1-16.5]). More than 2 positive antimicrobial antibody titres were associated with non-response (p < 0.05), but did not retain significance in multivariate analysis (p = 0.197; OR 0.632; 95% CI 0.31-1.2).

CONCLUSIONS

Infliximab can effectively treat inflammatory pouch complications. Pre-treatment mPDAI <10 and early endoscopy may identify responders.

Clinical Utility of Biomarkers in IBD

There is no gold standard for the diagnosis and monitoring of inflammatory bowel diseases (IBD). Biomarkers are useful tools for the management of patients suffering from IBD. However, they should be used only when their additional information is useful for clinical decision-making. In principal, four situations during the management of an individual IBD patient can be discriminated from a clinical standpoint in which biomarkers provide useful information. First, biomarkers may be helpful when the diagnosis of IBD is established and aid in the discrimination between ulcerative colitis (UC) and Crohn's disease (CD) is necessary. Second, biomarkers may be helpful in the prognostic evaluation of IBD severity or disease behavior and for early decisions on the best treatment. The third situation in which biomarkers are useful is the evaluation of disease activity during the disease course, for monitoring and for guidance of ongoing treatment. Finally, the fourth typical situation when biomarkers are of value is after surgery to predict or diagnose a relapse of the disease. From a clinical point of view, it may be more useful to discuss specific biomarkers and their individual value and impact in these four prototypic situations than to sum up advantages and disadvantages for each biomarker isolated from the clinical situation. Therefore, this overview is structured in chapters reflecting those four typical situations during the disease course of IBD patents to critically evaluate the potential and value of each of the biomarkers in the specific situation.

Nonbloody Diarrhea but Not Significant Weight Loss at Diagnosis Is Associated with the Development of Denovo Crohn's Disease After Ileal Pouch-anal Anastomosis for Ulcerative Colitis

BACKGROUND

Denovo Crohn's disease (CD) develops in 5% to 10% of patients after ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC) leading to increased morbidity and rates of pouch failure. Initial nonbloody diarrhea and weight loss at diagnosis are independent risk factors for a change in diagnosis from UC to CD in nonsurgical patients. We investigated whether these features were risk factors for denovo CD in a longitudinal cohort of patients with UC undergoing IPAA.

METHODS

Prospective profiles of patients with UC undergoing IPAA followed over a 22-year period by 1 surgeon were analyzed. Denovo CD was diagnosed when mucosal inflammation (5 or more ulcers) involved the small bowel mucosa proximal to the ileal pouch any time after surgery and/or when a pouch fistula or other perianal complication developed more than 3 months after ileostomy closure. Patients with inflammatory bowel disease unclassified, acute pouchitis, chronic pouchitis, and those lost to follow-up were excluded from analysis. Cox regression analysis was performed for statistical significance.

RESULTS

Of the 199 study patients included in the analysis, denovo CD developed in 42 patients (21%). Patients who developed denovo CD had an increased incidence of nonbloody diarrhea (n = 12; 29%) compared with patients who had no evidence of pouch inflammation (n = 25; 16%) (P = 0.03). In contrast, the incidence of weight loss was not significantly increased in patients with denovo CD (n = 7; 17%) compared with patients who never had pouch inflammation (n = 16; 10%) (P = 0.12).

CONCLUSIONS

Initial nonbloody diarrhea is associated with denovo CD after IPAA. This association warrants close consideration before surgery.

Frequency, Clinical Features and Factors Associated with Pouchitis after Proctocolectomy with Ileo-Pouch-Anal Anastomosis in Patients with Ulcerative Colitis: A Latin-American Country Retrospective-Cohort Study

BACKGROUND

Pouchitis is the most common complication of proctocolectomy with ileo-pouch-anal anastomosis (IPAA) for ulcerative colitis (UC). No previous study in Mexico has evaluated this issue; our aim was to evaluate its frequency, clinical characteristics and factors associated with its presence in Mexican patients with UC and IPAA.

METHODS

Retrospective-cohort study including 70 patients with histopathological diagnosis of UC and IPAA between 1983 and 2014 from inflammatory bowel disease clinic of a tertiary care center. The statistical analysis used descriptive statistics, chi-square and Fisher's exact test for categorical variables and Student's t test for numeric variables. Univariate analysis was performed to identify the factors associated.

RESULTS

Patients presenting with pouchitis accounted for 48.6%. From the 34 cases, 12 (35.3%) had inactive pouchitis; 7 (20.6%) active acute pouchitis; 15 (44.1%) chronic active pouchitis. On average, pouchitis occurred 5.37 years after IPPA. Factors probably associated with its occurrence were the presence of autoimmune concomitant diseases (ACDs; p = 0.06, OR 4.40, 95% CI 0.84-22.9) and extra-intestinal manifestations (EIMs; p = 0.05, OR 2.53, 95% CI 0.96-6.64), which was also probably associated with chronic active pouchitis (p = 0.06, OR 0.31, 95% CI 0.07-1.31).

CONCLUSIONS

The frequency of pouchitis is high in Mexican UC patients after IPAA. ACDs and EIMs were probably associated with its development.

Diagnostic and Prognostic Microbial Biomarkers in Inflammatory Bowel Diseases

The microbiome plays multifaceted roles in the pathogenesis of inflammatory bowel diseases (IBD). Accordingly, the clinical challenge of patient heterogeneity in disease phenotype and response to treatment should in part be addressed by biomarkers that detect the host response to microbiota, and the levels of microbial taxa and products eliciting the host response in susceptible individuals. Molecular analysis has revealed much evidence for microbial taxonomic membership and microbial products in association with IBD, but their utility as clinical biomarkers is still in its infancy. A rich area of progress has been the development and validation of host serologic microbial biomarkers, which have achieved a distinctive position in the diagnosis and prognosis in IBD, and as a template for defining other categories of microbial biomarkers in disease state and phenotype.

Serology of Patients with Ulcerative Colitis After Pouch Surgery Is More Comparable with that of Patients with Crohn's Disease

BACKGROUND

The serologic status of patients with ulcerative colitis (UC) who develop postoperative pouchitis was compared with that of patients with Crohn's disease (CD) and unoperated patients with UC.

METHODS

Pouch patients were stratified into normal pouch, acute/recurrent acute pouchitis, and chronic pouchitis/Crohn's-like disease of the pouch groups. Antibodies against glycans associated with CD (anti-Saccharomyces cerevisiae, anti-laminaribioside, anti-chitobioside, and anti-mannobioside carbohydrate antibodies [ASCA, ALCA, ACCA, and AMCA, respectively]) were detected and correlated with type of inflammatory bowel disease and pouch behavior.

RESULTS

A total of 501 patients with inflammatory bowel diseases were recruited: 250 (50%) CD, 124 (24.7%) unoperated UC, and 127 (25.3%) UC-pouch. At least 1 positive antibody was detected in 77.6% CD, 52.0% UC-pouch and 33.1% unoperated UC (P < 0.0001 for all). ACCA and AMCA prevalence in CD, UC-pouch and unoperated patients with UC were 33.2%, 24.4%, and 16.9% (P = 0.003 for all) and 35.2%, 26.8%, and 7.3%, respectively (P < 0.0001 for all). ALCA and ASCA were more prevalent in patients with CD than unoperated UC and UC-pouch patients. A longer interval since pouch surgery was associated with inflammatory pouch behavior: 12.45, 11.39, and 8.5 years for acute/recurrent acute pouchitis, chronic pouchitis/Crohn's-like disease of the pouch, and normal pouch, respectively, P = 0.01 for all.

CONCLUSIONS

The prevalence of the CD-associated anti-glycan antibodies ACCA and AMCA is significantly increased in UC-pouch patients, suggesting that pouch surgery may trigger differential immune responses to glycans. The finding that the serology of UC-pouch patients shares similarities with that of patients with CD supports the notion that those 2 inflammatory bowel diseases share a common pathogenic pathway.

Differential response to microbial antigens by age of diagnosis in patients with Crohn's disease

PURPOSE

Fifteen percent of incident Crohn's disease (CD) cases are diagnosed at older ages and demonstrate colonic location and inflammatory behavior. Serologic responses to gut microbial antigens are associated with specific phenotypes, and may differ by age at diagnosis. Our aim was to identify an association between age at diagnosis of CD and responses to gut microbial antigens.

PATIENTS AND METHODS

Levels of anti-Saccharomyces cerevisiae antibodies (ASCA) immunoglobulins A and G (IgA and IgG), antibodies to Escherichia coli outer membrane porin-C (anti-Omp-C), antibodies to clostridial flagellin (anti-CBir-1), and perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA) were compared in patients by age in three diagnosis groups: patients diagnosed at ages of <40, ≥40-59, and ≥60 years. For each antigen, patients with antibody levels in the first, second, third, and fourth quartile were assigned a score of 1, 2, 3, or 4, respectively. Individual scores were added to create a quartile sum score representing cumulative quantitative immune response.

RESULTS

Eighteen, 17, and 12 patients were diagnosed at ages <40, 40-59, and ≥60 years, respectively. The majority (71%) had ileocolonic disease in the youngest group, compared to 36% in the oldest group (P=0.001). Mean ASCA IgA and IgG titers were increased in the youngest age group compared to the older groups (P=0.19 and P=0.13, respectively). Mean quartile sum scores for antibody levels were 7.2±2.8 in those patients diagnosed at ages <40 years, 4.9±2.9 in the 40-59-year-old age group, and 5.6±2.6 in the ≥60-year-old age group (P=0.06).

CONCLUSION

A trend toward decreased cumulative immune responses to CD-associated gut antigens was observed in CD patients diagnosed at older ages compared to younger patients. Host responses to microbial antigens may be less important in older onset IBD and may contribute to the distinct phenotype in this group.

The use of prognostic factors in inflammatory bowel diseases

The disease spectrum and natural course of Crohn's disease and ulcerative colitis are highly variable. The majority of Crohn's disease patients will require surgery at a certain stage in their disease compared to only a fraction of the ulcerative colitis patients. Similarly, some patients are destined to experience an indolent disease course while others will require early intensive therapy. Ideally, these subtypes of patients should be identified as early as possible with the help of reliable prognostic factors in order to guide personalized therapeutic decisions. In this review, the authors focused on the most relevant reports on the use of different prognostic factors to predict disease course, postoperative recurrence and response to therapy in patients with inflammatory bowel disease. The last 15 years have seen a wealth of novel genetic and serological markers of disease severity. Nevertheless, none of these markers have proven to be superior to careful clinical phenotyping and endoscopic features early in the disease course. Future attempts should apply an integrated approach that unites clinical, serological and (epi)genetic information with environmental influences, with a clear focus on the microbiome to ultimately identify molecular-based and clinically relevant subgroups.

Male issues of the ileal pouch

: Restorative proctocolectomy with ileal pouch-anal anastomosis is the standard surgical treatment modality for patients with ulcerative colitis who require colectomy. There are special issues related to male gender. We performed systemic literature review on the topic, incorporating the experience in our specialized Center for Ileal Pouch Disorders, and provide recommendations for the identification and management for the gender-specific issues in male patients with ileal pouches. Chronic pouchitis, particularly ischemic pouchitis, anastomotic leak, and presacral sinus are more common in male patients than their female counterparts. Sexual dysfunction can occur after pouch surgery, particularly in those with pouch failure. Diagnosis and management of benign and malignant prostate diseases can be challenging due to the altered pelvic anatomy from the surgery. Digital rectal examination for prostate cancer screening is not reliable. Transpouch biopsy of prostate may lead to pouch fistula or abscess. Pelvic radiation therapy may have an adverse impact on the pouch function. In conclusion, sexual dysfunction and enlarged prostate can occur in patients with the ileal pouch. The measurement of serum prostate-specific antigen is a preferred method for the screening of prostate cancer. If biopsy of the prostate is needed, the perineal route is recommended. The risk for pouch dysfunction and the benefit for oncologic survival of pelvic radiation for prostate cancer should be carefully balanced.

Differential diagnosis in inflammatory bowel disease colitis: State of the art and future perspectives

Distinction between Crohn’s disease of the colon-rectum and ulcerative colitis or inflammatory bowel disease (IBD) type unclassified can be of pivotal importance for a tailored clinical management, as each entity often involves specific therapeutic strategies and prognosis. Nonetheless, no gold standard is available and the uncertainty of diagnosis may frequently lead to misclassification or repeated examinations. Hence, we have performed a literature search to address the problem of differential diagnosis in IBD colitis, revised current and emerging diagnostic tools and refined disease classification strategies. Nowadays, the differential diagnosis is an untangled issue, and the proper diagnosis cannot be reached in up to 10% of patients presenting with IBD colitis. This topic is receiving emerging attention, as medical therapies, surgical approaches and leading prognostic outcomes require more and more disease-specific strategies in IBD patients. The optimization of standard diagnostic approaches based on clinical features, biomarkers, radiology, endoscopy and histopathology appears to provide only marginal benefits. Conversely, emerging diagnostic techniques in the field of gastrointestinal endoscopy, molecular pathology, genetics, epigenetics, metabolomics and proteomics have already shown promising results. Novel advanced endoscopic imaging techniques and biomarkers can shed new light for the differential diagnosis of IBD, better reflecting diverse disease behaviors based on specific pathogenic pathways.

Autoimmune features are associated with chronic antibiotic-refractory pouchitis

BACKGROUND

Chronic antibiotic-refractory pouchitis (CARP) occurs more frequently in patients with ileal pouch-anal anastomosis (IPAA) with concomitant autoimmune disorders. The aim of this study was to assess the overlap between dysregulated immune features in patients with IPAA and their association with CARP.

METHODS

We identified 150 symptomatic patients with IPAA who met inclusion criteria, including measurement of select autoimmune serology. Demographic and clinical variables were compared between patients with and without CARP.

RESULTS

Autoimmune thyroid disease was more frequent among patients with CARP. The frequency of primary sclerosing cholangitis (16.7% versus 5.3%; P = 0.04) and serum positivity for microsomal antibody (25% versus 6.1%, P = 0.003) were significantly greater in patients with CARP compared with non-CARP patients, respectively. Increased tissue infiltration by IgG4-expressing plasma cells was detected in 17 of 31 patients (54.8%) in the CARP group as compared with 10/67 (14.9%) in the non-CARP group (P = 0.0001). Forty-seven percent of patients in the CARP group versus 22.8% in the non-CARP group had at least 2 immune features (P = 0.019). Among patients with IgG4 histology, 87% of patients in the CARP group versus 60% in the non-CARP group had at least 1 immune marker (P = 0.004). On multivariate analysis, microsomal antibody expression (odds ratio, 6.8; 95% confidence interval, 1.3-42.6; P = 0.02) and increased IgG4-expressing plasma cells tissue infiltration (odds ratio, 9.6; 95% confidence interval, 3.2-32.6, P = 0.0001) were risk factors for CARP.

CONCLUSIONS

There is marked overlap of certain immune markers in patients with pouch dysfunction, especially those with CARP. Microsomal antibody expression and elevated IgG4-positive plasma cell infiltration were independent risk factors for CARP.

Systematic review: new serological markers (anti-glycan, anti-GP2, anti-GM-CSF Ab) in the prediction of IBD patient outcomes

Traditionally, IBD diagnosis is based on clinical, radiological, endoscopic, and histological criteria. Biomarkers are needed in cases of uncertain diagnosis, or to predict disease course and therapeutic response. No guideline recommends the detection of antibodies (including ASCA and ANCA) for diagnosis or prognosis of IBD to date. However, many recent data suggest the potential role of new serological markers (anti-glycan (ACCA, ALCA, AMCA, anti-L and anti-C), anti-GP2 and anti-GM-CSF Ab). This review focuses on clinical utility of these new serological markers in diagnosis, prognosis and therapeutic monitoring of IBD. Literature review of anti-glycan, anti-GP2 and anti-GM-CSF Ab and their impact on diagnosis, prognosis and prediction of therapeutic response was performed in PubMed/MEDLINE up to June 2014. Anti-glycan, anti-GP2 and anti-GM-CSF Ab are especially associated with CD and seem to be correlated with complicated disease phenotypes even if results differ between studies. Although anti-glycan Ab and anti-GP2 Ab have low sensitivity in diagnosis of IBD, they could identify a small number of CD patients not detected by other tests such as ASCA. Anti-glycan Abs are associated with a progression to a more severe disease course and a higher risk for IBD-related surgery. Anti-GP2 Ab could particularly contribute to better stratify cases of pouchitis. Anti-GM-CSF Ab seems to be correlated with disease activity and could help predict relapses. These new promising biomarkers could particularly be useful in stratification of patients according to disease phenotype and risk of complications. They could be a valuable aid in prediction of disease course and therapeutic response but more prospective studies are needed.

Relationship between pouch microbiota and pouchitis following restorative proctocolectomy for ulcerative colitis

Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) has become the surgical treatment of choice for many patients with medically refractory ulcerative colitis (UC) and familial adenomatous polyposis (FAP). UC patients with IPAA (UC-IPAA) are, nevertheless, susceptible to inflammatory and noninflammatory sequelae such as pouchitis, which is only rarely noted in FAP patients with IPAA. Pouchitis is the most frequent long-term complication of UC-IPAA patients, with a cumulative prevalence of up to 50%. Although the aetiology of pouchitis remains unclear, accumulating evidence suggests that a dysbiosis of the pouch microbiota and an abnormal mucosal immune response are implicated in its pathogenesis. Studies using culture and molecular techniques have detected a dysbiosis of the pouch microbiota in patients with pouchitis. Risk factors, genetic associations, and serological markers suggest that interactions between the host immune response and the pouch microbiota underlie the aetiology of this idiopathic inflammatory condition. This systematic review focuses on the dysbiosis of the microbiota that inhabit the pouch in UC and FAP patients and its interaction with the mucosal immune system. A meta-analysis was not attempted due to the highly heterogeneous microbiota composition and the different detection methods used by the various studies. Although no specific bacterial species, genus, or family has as yet been identified as pathogenic, there is evidence that a dysbiosis characterized by decreased gut microbiota diversity in UC-IPAA patients may, in genetically predisposed subjects, lead to aberrant mucosal immune regulation triggering an inflammatory process.

Role of intestinal bacteria in the pathogenesis of pouchitis

Pouchitis is a common complication seen in patients with ulcerative colitis who undergo total proctocolectomy with ileal pouch anal anastomosis. Bacteria seem to play an important role in the development of pouchitis, although this role is not well defined. Because technology has advanced, we are able to apply molecular techniques to describe the structure and function of the pouch microbial community. In recent years, several studies have been performed comparing the pouch microbiota in patients with ulcerative colitis with healthy pouches and pouchitis. Many of these studies have suggested that pouchitis is characterized by dysbiosis and/or decreased microbial diversity. There has not been a clear pattern identifying a pathogenic organism or a group of organisms responsible for pouchitis. This review summarizes recent studies exploring the pouch microbiota in health and disease, the relationship of bacterial metabolites and pouchitis, and the role of antibiotics and probiotics for the treatment and prevention of pouchitis.

Treatment strategy for preventing pouchitis as a postoperative complication of ulcerative colitis: the significance of the management of cuffitis

PURPOSE

The aim of this study was to examine the risk factors for and to evaluate strategies for preventing pouchitis as a postoperative complication of ulcerative colitis (UC).

METHODS

A total of 119 cases of UC in which restorative proctocolectomy with an ileal pouch-anal anastomosis (IPAA) was performed at our institution between 2000 and 2012 was investigated; nine patients in whom it was impossible to close the ileostomy due to an intractable anal fistula or pelvic abscess were excluded.

RESULTS

The cumulative risk of developing pouchitis 5 years after IPAA with stoma closure was 31.0%. Significant relationships with pouchitis were found for the surgical indication (p = 0.0126) and surgical method (p = 0.0214). A significant correlation was found between pouchitis and cuffitis. Pouchitis was significantly more common in the cases with cuffitis than in those without (p = 0.0002). There was also a significantly different cumulative incidence observed between the cases with and without cuffitis (p < 0.0001). In addition, pouchitis had a greater tendency to recur in the cases with cuffitis than in those without (p = 0.2730).

CONCLUSION

The cumulative incidence rate of pouchitis was 10.6% at 1 year, 15.1% at 2 years and 31.0% at 5 years. Controlling cuffitis is important to prevent pouchitis.

Can we predict the high-risk patient?

BACKGROUND

While therapeutic strategies able to change the natural history of inflammatory bowel diseases (IBD) are being developed, factors predicting aggressive disease are needed to be able to choose the appropriate therapeutic strategy for the individual patient based on the risk/benefit ratio. The aim of this review is to focus on the tools assisting the clinician in routine practice regarding the prediction of disease evolution.

METHODS

A literature review was performed, which was mainly based on PubMed search, using the following terms: Crohn's disease, ulcerative colitis, inflammatory bowel disease, genetics, serology, biomarkers, endoscopy, C-reactive protein, faecal calprotectin, disease evolution and complications.

RESULTS

For the prediction of disease evolution, clinical characteristics, particularly disease location and behaviour, are probably currently the most useful. In addition, a series of biomarkers, including genetic, serological and inflammatory markers, as well as characteristics of endoscopic lesions may have an added value.

CONCLUSIONS

Simple clinical, biological and endoscopic tools may help the clinician in predicting disease evolution in IBD. However, these tools are still insufficient, and prospective evaluation of new genetic and biological markers are needed.

New serological markers in pediatric patients with inflammatory bowel disease

The spectrum of serological markers associated with inflammatory bowel disease (IBD) is rapidly growing. Due to frequently delayed or missed diagnoses, the application of non-invasive diagnostic tests for IBD, as well as differentiation between ulcerative colitis (UC) and Crohn’s disease (CD), would be useful in the pediatric population. In addition, the combination of pancreatic autoantibodies and antibodies against Saccharomyces cerevisiae antibodies/perinuclear cytoplasmic antibody (pANCA) improved the sensitivity of serological markers in pediatric patients with CD and UC. Some studies suggested that age-associated differences in the patterns of antibodies may be present, particularly in the youngest children. In CD, most patients develop stricturing or perforating complications, and a significant number of patients undergo surgery during the disease course. Based on recent knowledge, serum antibodies are qualitatively and quantitatively associated with complicated CD behavior and CD-related surgery. Pediatric UC is characterized by extensive colitis and a high rate of colectomy. In patients with UC, high levels of anti-CBir1 and pANCA are associated with the development of pouchitis after ileal pouch-anal anastomosis. Thus, serologic markers for IBD can be applied to stratify IBD patients into more homogeneous subgroups with respect to disease progression. In conclusion, identification of patients at an increased risk of rapid disease progression is of great interest, as the application of early and more aggressive pharmaceutical intervention could have the potential to alter the natural history of IBD, and reduce complications and hospitalizations.

The association between autoimmunity and pouchitis

: Restorative proctocolectomy with ileal pouch-anal anastomosis is commonly used in the management of ulcerative colitis. Inflammation of the ileal pouch reservoir, or pouchitis, is a common complication of ileal pouch-anal anastomosis that is incompletely understood. Risk factors including nonsmoker status and primary sclerosing cholangitis have been linked with pouchitis development, but the etiopathogenesis of pouchitis remains poorly defined. Pouchitis is more commonly a complication of ileal pouch-anal anastomosis performed in patients with ulcerative colitis, and similar to ulcerative colitis, chronic pouchitis is associated with extraintestinal manifestations and other diseases of immune origin, suggesting overlap in the disease pathogenesis. It is becoming apparent that pouchitis encompasses clinically distinct subtypes based on the response or lack of response to antibiotic therapy. There is also emerging evidence of the role of autoimmunity in a subgroup of patients with pouchitis, including patients with concurrent primary sclerosing cholangitis, seropositivity for immunoglobulin G4, or infiltration of immunoglobulin G4-expressing plasma cells in the pouch mucosa. The identification of underlying autoimmunity may have important clinical implications in the diagnosis, subclassification, and management of pouchitis.