Antimicrobial antibodies are associated with a Crohn's disease-like phenotype after ileal pouch-anal anastomosis

From ASCA breakthrough in Crohn's disease and Candida albicans research to thirty years of investigations about their meaning in human health

Anti-Saccharomyces cerevisiae antibodies (ASCA) are human antibodies that can be detected using an enzyme-linked immunosorbent assay involving a mannose polymer (mannan) extracted from the cell wall of the yeast S. cerevisiae. The ASCA test was developed in 1993 with the aim of differentiating the serological response in two forms of inflammatory bowel disease (IBD), Crohn's disease and ulcerative colitis. The test, which is based on the detection of anti-oligomannosidic antibodies, has been extensively performed worldwide and there have been hundreds of publications on ASCA. The earlier studies concerned the initial diagnostic indications of ASCA and investigations then extended to many human diseases, generally in association with studies on intestinal microorganisms and the interaction of the micro-mycobiome with the immune system. The more information accumulates, the more the mystery of the meaning of ASCA deepens. Many fundamental questions remain unanswered. These questions concern the heterogeneity of ASCA, the mechanisms of their generation and persistence, the existence of self-antigens, and the relationship between ASCA and inflammation and autoimmunity. This review aims to discuss the gray areas concerning the origin of ASCA from an analysis of the literature. Structured around glycobiology and the mannosylated antigens of S. cerevisiae and Candida albicans, this review will address these questions and will try to clarify some lines of thought. The importance of the questions relating to the pathophysiological significance of ASCA goes far beyond IBD, even though these diseases remain the preferred models for their understanding.

Risks Factors Associated with the Development of Crohn's Disease After Ileal Pouch-Anal Anastomosis for Ulcerative Colitis: A Systematic Review and Meta-Analysis

BACKGROUND

Following ileal pouch-anal anastomosis [IPAA] for ulcerative colitis [UC], up to 16% of patients develop Crohn's disease of the pouch [CDP], which is a major cause of pouch failure. This systematic review and meta-analysis aimed to identify preoperative characteristics and risk factors for CDP development following IPAA.

METHODS

A literature search of the MEDLINE, EMBASE, EMCare and CINAHL databases was performed for studies that reported data on predictive characteristics and outcomes of CDP development in patients who underwent IPAA for UC between January 1990 and August 2022. Meta-analysis was performed using random-effect models and between-study heterogeneity was assessed.

RESULTS

Seven studies with 1274 patients were included: 767 patients with a normal pouch and 507 patients with CDP. Age at UC diagnosis (weighted mean difference [WMD] -2.85; 95% confidence interval [CI] -4.39 to -1.31; p = 0.0003; I2 54%) and age at pouch surgery [WMD -3.17; 95% CI -5.27 to -1.07; p = 0.003; I2 20%) were significantly lower in patients who developed CDP compared to a normal pouch. Family history of IBD was significantly associated with CDP (odds ratio [OR] 2.43; 95% CI 1.41-4.19; p = 0.001; I2 31%], along with a history of smoking [OR 1.80; 95% CI 1.35-2.39; p < 0.0001; I2 0%]. Other factors such as sex and primary sclerosing cholangitis were found not to increase the risk of CDP.

CONCLUSIONS

Age at UC diagnosis and pouch surgery, family history of IBD and previous smoking have been identified as potential risk factors for CDP post-IPAA. This has important implications towards preoperative counselling, planning surgical management and evaluating prognosis.

Crohn's of the Pouch: Now What?

Total proctocolectomy and ileal pouch anal anastomosis (IPAA) is the gold standard surgical treatment for the majority (∼90%) of ulcerative colitis (UC) patients. In cases of carefully selected Crohn's colitis patients without small bowel or perianal involvement an "intentional IPAA" may be a viable option for disease resection and restoration of intestinal continuity. More commonly, Crohn's is incidentally found either in the resection specimen or, more commonly, when inflammatory complications subsequently arise after pouch construction for UC or indeterminate colitis. These incidental Crohn's pouches may be diagnosed early or late period post-IPAA. Crohn's may manifest within the pouch, in the proximal small bowel, and/or distally in the rectal cuff or anus. Like intestinal Crohn's, Crohn's disease of the pouch may be of an inflammatory, fibrostenosing, or fistulizing phenotype. Treatment depends on the phenotype and includes medical treatment, most commonly in the form of tumor necrosis factor inhibitor medications; however, the newer small molecules offer a potential treatment for these patients. Surgery first entails treating the sequelae of Crohn's and is typically staged. In up to 60% of Crohn's pouches, particularly in fistulizing disease and/or recalcitrant perianal disease, the pouch fails and must be defunctioned or excised. In patients with Crohn's pouches in situ long term, outcomes including quality of life are comparable to patients who underwent IPAA for UC.

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.

Time to Revisit Disease Classification in Inflammatory Bowel Disease: Is the Current Classification of Inflammatory Bowel Disease Good Enough for Optimal Clinical Management?

Inflammatory bowel disease (IBD), historically subdivided into Crohn's disease and ulcerative colitis, is a very heterogeneous condition. While the tendency in medicine is to try to reduce complexity, IBD is a disease that cannot justify a one-size-fits-all principle. Our current clinical classification tools are suboptimal and need further refinement to capture, at least in part, the variety of phenotypes encountered in daily clinical practice. Although these revised classification tools alone will not be sufficient and should be complemented by more detailed molecular subclassifications, optimized clinical phenotypes can contribute to improved trial designs, future translational research approaches, and better treatment outcomes. In the current review, we discuss key clinical features important in IBD disease heterogeneity, tackle limitations of the current classification systems, propose some potential improvements, and raise priorities for future research in this domain.

Chronic pouchitis and Crohn's disease of the pouch after ileal pouch-anal anastomosis: Incidence and risk factors

BACKGROUND

Restorative proctocolectomy with ileal-pouch anal-anastomosis (IPAA) is the operation of choice for patients with ulcerative colitis (UC) or with inflammatory bowel diseases unclassified (IBDU).

AIMS

to assess the incidence and risk factors of chronic pouchitis (CP) and Crohn's disease of the pouch (CDP) in patients with UC or IBDU.

METHODS

We conducted a retrospective study. We included consecutive patients who underwent IPAA between 2011 and 2019. The main outcome was the occurrence of CP or CDP. We looked for risk factors with multivariable and a least absolute shrinkage and selection operator (LASSO) Cox models.

RESULTS

247 patients were included. The 5-year cumulative incidence of CP or CDP was 35.3% (95%CI: 26.2-43.2). In multivariable analysis, diagnosis of IBDU, age less than 35 years at surgery and extra-intestinal manifestations other than articular and primary sclerosing cholangitis were associated with higher incidence. The LASSO analysis identified these three prognostic factors and articular manifestations. In patients with two or more prognostic factors, 5-year cumulative incidence, was 65.2% (95%CI: 41.8-79.2).

CONCLUSIONS

Five years after IPAA, approximately one-third of patients had either CP or CDP. Risk factors were IBDU, an age less than 35 years at surgery, articular manifestations and other extra-intestinal manifestations.

Diagnosis and classification of ileal pouch disorders: consensus guidelines from the International Ileal Pouch Consortium

Restorative proctocolectomy with ileal pouch-anal anastomosis is an option for most patients with ulcerative colitis or familial adenomatous polyposis who require colectomy. Although the construction of an ileal pouch substantially improves patients' health-related quality of life, the surgery is, directly or indirectly, associated with various structural, inflammatory, and functional adverse sequelae. Furthermore, the surgical procedure does not completely abolish the risk for neoplasia. Patients with ileal pouches often present with extraintestinal, systemic inflammatory conditions. The International Ileal Pouch Consortium was established to create this consensus document on the diagnosis and classification of ileal pouch disorders using available evidence and the panellists' expertise. In a given individual, the condition of the pouch can change over time. Therefore, close monitoring of the activity and progression of the disease is essential to make accurate modifications in the diagnosis and classification in a timely manner.

Outcomes Following Pouch Formation in Paediatric Ulcerative Colitis: A Study From the Porto Group of ESPGHAN

INTRODUCTION

Contemporary pediatric data on pouch outcomes are sparse, especially in the era of laparoscopic surgeries. We aimed to assess outcomes and predictors in children with ulcerative colitis/inflammatory bowel disease (IBD)-unclassified who underwent colectomy and ileal pouch-anal anastomosis.

METHODS

This was a multicenter retrospective cohort study from 17 IBD centers affiliated with the pediatric IBD Porto group of ESPGHAN. An electronic REDcap system was used to collate baseline characteristics, demographic, clinical, management and surgical data, short- and long-term outcomes, and to identify potential predictors of pouch outcome.

RESULTS

Of the 129 patients included, 86 (67%) developed pouchitis during follow-up of median 40 months (interquartile range 26-72), of whom 33 (26%) with chronic pouchitis. Patients operated on by surgeons performing <10 pouch surgeries/year had a higher rate of chronic pouchitis (11/27 [41%] vs 8/54 [15%], P = 0.013) on both univariable and multivariable analyses and also associated with time to pouchitis (P = 0.018) and chronic pouchitis (P = 0.020). At last follow-up, overall pouch performance was rated good/excellent in 86 (74%) patients. Time from colectomy to pouch formation was not associated with pouch outcomes. Despite higher rate of nonsevere surgical complications among children undergoing colectomy at <10 years of age (7/16 [44%] vs 10/92 [11%], P = 0.003), functional outcome and pouchitis rate did not differ.

CONCLUSIONS

Pouchitis rate in children with ulcerative colitis/IBD unclassified is high. Surgeon experience is the major modifiable risk factor for pouch outcome. Our analyses suggest that pouch surgery can also be performed successfully in young children.

The Incidence and Definition of Crohn's Disease of the Pouch: A Systematic Review and Meta-analysis

BACKGROUND

A subset of patients who undergo total proctocolectomy with ileal pouch-anal anastomosis (IPAA) creation for ulcerative colitis (UC) will later develop Crohn's disease (CD) of the pouch, which has been associated with significant morbidity. We aimed to analyze the incidence of CD of the pouch and to review the existing diagnostic criteria utilized.

METHODS

A systematic search performed through March 1, 2018, identified 12 studies that reported the incidence of CD of the pouch after IPAA for UC or indeterminate colitis (IC). We compiled all diagnostic criteria utilized in these studies and then performed a meta-analysis using random effects modeling to estimate the overall incidence of CD of the pouch in this population.

RESULTS

Among 4843 patients with an IPAA for UC or IC, 10.3% of patients were ultimately diagnosed with CD of the pouch (95% confidence interval [CI], 6.1%-15.4%). The most commonly reported diagnostic criteria were (1) presence of fistula/fistulae, (2) stricture involving the pouch or prepouch ileum, and (3) presence of prepouch ileitis. In a secondary analysis, excluding those studies that included patients with a preoperative diagnosis of IC, the incidence of CD of the pouch was 12.4% (95% CI, 9.0%-16.1%).

CONCLUSIONS

The estimated incidence of 10.3% will assist gastroenterologists and surgeons in preoperative counseling regarding the potential to develop CD of the pouch. There is an unmet need for common diagnostic criteria for a more standardized approach to the diagnosis of CD of the pouch.

Starch Consumption May Modify Antiglycan Antibodies and Fecal Fungal Composition in Patients With Ileo-Anal Pouch

BACKGROUND

Inflammatory bowel diseases (IBDs) are characterized by serologic responses to glycans. Patients with ulcerative colitis (UC) after proctocolectomy with ileo-anal anastomosis (pouch surgery) may develop inflammation (pouchitis) that resembles Crohn's disease (CD). We hypothesized that patients' serologic responses were affected by their consumption of dietary sugars. This study analyzed the correlations between antiglycan antibody expression and dietary sugar consumption in patients with UC pouch and the evolution in antibody levels over time.

METHODS

Patients were followed prospectively for 2 consecutive visits. The following antiglycan carbohydrate antibodies were detected by enzyme-linked immunosorbent assay: antichitobioside (ACCA), antilaminaribioside (ALCA), antimannobioside (AMCA), and anti-Saccharomyces cerevisiae (ASCA) antibodies. Patients completed a food frequency questionnaire. The fungal community in patients' fecal samples was analyzed by sequencing the internal transcribed spacer 2 (ITS2) region of nuclear ribosomal DNA.

RESULTS

We included 75 UC pouch patients aged 45.2 ± 14 years who underwent pouch surgery 9.8 ± 6.7 years previously. Of these patients, 34.7% (n = 26) showed seropositivity for antiglycan antibodies. Starch consumption was significantly higher in patients with positive serologic responses (P = 0.05). Higher starch consumption was associated with higher AMCA and ACCA titers, which increased by 4.08% (0.8%-7.4%; P = 0.014) and 4.8% (0.7%-9.1%; P = 0.007), respectively, for each 10-g increase of dietary starch. The per-patient change in the relative abundance of Candida albicans in fecal samples correlated positively with changes in starch consumption (Spearman's r = 0.72; P = 0.012).

CONCLUSIONS

Starch consumption correlated with positive antiglycan serology (ACCA and AMCA), suggesting that increased dietary starch intake may promote a specific immune response in patients with IBD.

Genotype-Serotype Interactions Shed Light on Genetic Components of Inflammatory Bowel Diseases

BACKGROUND

We evaluated the impact of variations in ATG16L1 and NOD2 and genes on serologic responses in patients with inflammatory bowel disease (IBD).

METHODS

We recruited 308 IBD patients: 130 with Crohn's disease (CD), 67 with ulcerative colitis (UC), 111 with UC and an ileal pouch (UC-pouch), and 74 healthy controls. NOD2 variants (1007fs, G908R, R702W) and the ATG16L1 A300T variant were analyzed. The antiglycan antibodies anti-Saccharomyces cerevisiae (ASCA), antilaminaribioside (ALCA), antichitobioside (ACCA), and antimannobioside carbohydrate (AMCA) were analyzed by enzyme-linked immunosorbent assay.

RESULTS

Antichitobioside was positive in 28% of patients with CD carrying the ATG16L1 A300T variant (either heterozygote or homozygote) compared with only 3% in those without the variant (P < 0.001). Anti-Saccharomyces cerevisiae was positive in 86% of patients with CD carrying the NOD2 1007fs variant compared with 36% in those without the variant (P < 0.001). UC-pouch patients with the NOD2 1007fs variant had elevated ASCA and ALCA levels compared with those without the variant (50% vs 7%, P = 0.004, and 50% vs 8%, P = 0.006, respectively). Importantly, ATG16L1 A300T and NOD2 variants were not associated with serologic responses in healthy controls and unoperated UC patients. Multivariate analysis demonstrated that these genetic variants are the main factors associated with specific antiglycan antibody levels in CD and pouch patients.

CONCLUSIONS

Genetic variants may have disease-specific phenotypic (serotypic) effects. This implies that genetic risk factors may also be disease modifiers.

Loss of tolerance to glycoprotein 2 isoforms 1 and 4 is associated with Crohn's disease of the pouch

BACKGROUND

Zymogen granule glycoprotein 2 (GP2) is a major autoantigen of Crohn's disease-specific pancreatic autoantibodies.

AIM

To test a link between loss of tolerance to isoforms of GP2 and pouch disorders in a cross-sectional study in ulcerative colitis patients with ileal pouch-anal anastomosis (IPAA).

METHODS

Serum samples of 117 consecutive ulcerative colitis patients after IPAA were tested for presence of Anti-GP2 isoforms 1 (GP2₁ ) & 4 (GP2₄ ) IgG and IgA as well as anti-Saccaromyces cervisiae (ASCA) IgG and IgA antibodies in a blinded fashion via enzyme-linked immunosorbent assay. Pouch disorders were diagnosed based on clinical, endoscopic, histological and radiographic criteria. Crohn's disease of the pouch was defined as involvement of the small bowel mucosa proximal to the ileal pouch with Crohn's disease, development of perianal complications or pouch fistula more than 3 months after ileostomy closure.

RESULTS

Positivity and level of Anti-GP2₁ IgG (AUC 0.77; P < 0.001 & P = 0.02, respectively), Anti-GP2₄ IgG (AUC 0.74; P < 0.001 & P = 0.025, respectively) and Anti-GP2₄ IgA (AUC 0.77; P < 0.001 to P = 0.018, respectively) were specifically associated with Crohn's disease of the pouch. Anti-GP2 was not associated with endoscopic or histological pouch disease activity index. Neither positivity nor levels of ASCA IgG (AUC 0.63; P = 0.12 & P = 0.35, respectively) or ASCA IgA (AUC 0.67; P = 0.38 & P = 0.53) were associated with pouch phenotypes.

CONCLUSIONS

The novel anti-GP2₁ and GP2₄ antibodies are associated with Crohn's disease of the pouch in ulcerative colitis patients after IPAA. Serological anti-GP2 antibodies could aid in diagnosis of Crohn's disease of the pouch.

Management of Paediatric Ulcerative Colitis, Part 1: Ambulatory Care-An Evidence-based Guideline From European Crohn's and Colitis Organization and European Society of Paediatric Gastroenterology, Hepatology and Nutrition

BACKGROUND

The contemporary management of ambulatory ulcerative colitis (UC) continues to be challenging with ∼20% of children needing a colectomy within childhood years. We thus aimed to standardize daily treatment of pediatric UC and inflammatory bowel diseases (IBD)-unclassified through detailed recommendations and practice points.

METHODS

These guidelines are a joint effort of the European Crohn's and Colitis Organization (ECCO) and the Paediatric IBD Porto group of European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN). An extensive literature search with subsequent evidence appraisal using robust methodology was performed before 2 face-to-face meetings. All 40 included recommendations and 86 practice points were endorsed by 43 experts in Paediatric IBD with at least an 88% consensus rate.

RESULTS

These guidelines discuss how to optimize the use of mesalamine (including topical), systemic and locally active steroids, thiopurines and, for more severe disease, biologics. The use of other emerging therapies and the role of surgery are also covered. Algorithms are provided to aid therapeutic decision-making based on clinical assessment and the Paediatric UC Activity Index (PUCAI). Advice on contemporary therapeutic targets incorporating the use of calprotectin and the role of therapeutic drug monitoring are presented, as well as other management considerations around pouchitis, extraintestinal manifestations, nutrition, growth, psychology, and transition. A brief section on disease classification using the PIBD-classes criteria and IBD-unclassified is also part of these guidelines.

CONCLUSIONS

These guidelines provide a guide to clinicians managing children with UC and IBD-unclassified management to provide modern management strategies while maintaining vigilance around appropriate outcomes and safety issues.

Vedolizumab in the treatment of Crohn's disease of the pouch

Background

Our recent study showed the efficacy and safety of vedolizumab in the treatment of chronic antibiotic-refractory pouchitis. However, there are no published studies on its efficacy and safety in Crohn’s disease (CD) of the pouch. The aim of this study was to assess the efficacy and safety of vedolizumab in those patients.

Methods

This case series included all eligible patients with CD of the pouch from our prospectively maintained, IRB-approved Pouchitis Registry from 2015 to 2017. Disease activity in pouch patients can be monitored using the modified Pouchitis Disease Activity Index (mPDAI). mPDAI is the 18-point pouchitis disease activity index consisting of three principal component scores: symptom (range, 0–6 points), endoscopy, (range 0–6 points), and histology (range, 2–6 points). Pre- and post- treatment (minimum 6 months) pouchoscopy and clinical visits were used to calculate mPDAI.

Results

A total of 12 patients were included in this study, who had restorative proctocolectomy with ileal pouch anal anastomosis for medically refractory ulcerative colitis (UC). The mean age at the time of pre-colectomy diagnosis of UC was 25.0 ± 11.5 years. The mean current age was 41.0 ± 12.1 years, nine (75.0%) were female, three (25.0%) had smoked and eight (66.7%) had used anti-tumor necrosis factor agents prior to vedolizumab use. The mean duration of vedolizumab use was 1.0 ± 6.4 years. There was a significant reduction in mPDAI symptom subscores after vedolizumab therapy (3.50 ± 1.93 vs 5.08 ± 0.79, P = 0.015). The pre- and post-treatment mean endoscopy subscores were 1.25 ± 1.36 and 0.91 ± 1.50 in the afferent limb (P = 0.583); 2.58 ± 1.68 and 2.27 ± 2.05 (P = 0.701) in the pouch body; and 2.67 ± 1.93 and 2.09 ± 2.12 (P = 0.511) in the cuff, respectively. None of the patients experienced side effects throughout the vedolizumab therapy.

Conclusion

The findings of our study suggests that vedolizumab appears to be effective and safe in reducing the symptoms in patients with CD of the pouch.

Patchy colitis, and young age at diagnosis and at the time of surgery predict subsequent development of Crohn's disease after ileal pouch-anal anastomosis surgery for ulcerative colitis

BACKGROUND AND AIM

A proportion of patients having total proctocolectomy and ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC) are later diagnosed with Crohn's disease (CD). The aim of this study was to identify preoperative and perioperative predictors for the subsequent development of CD in patients who had IPAA for presumed UC.

METHODS

A retrospective case-control study of patients undergoing IPAA surgery for presumed UC was undertaken. Cases were patients who had a revised diagnosis of CD after surgery. Preoperative and perioperative variables were examined and analyzed.

RESULTS

Fifteen cases were compared with 39 controls. Patients aged ≤25 years at initial UC diagnosis were more likely to develop CD compared to those aged >25 years (odds ratio, OR [95% confidence interval, CI]: 7.1 [1.6-31.3]; P = 0.01). Patients aged ≤30 years at the time of colectomy had an increased risk of subsequent development of CD compared to those aged >30 years (OR [95% CI]: 4.5 [1.3-16.0]; P = 0.02). Cases were more likely to have patchy colitis on their colectomy specimen (OR [95% CI]: 6.7 [1.1-41.8]; P = 0.04). There was no significant difference between groups regarding transmural inflammation, ileitis, or fissuring ulcers on colectomy specimens, or preoperative C-reactive protein (CRP), albumin, family history, and smoking status.

CONCLUSION

Predictors of the development of CD in the pouch include young age at diagnosis and at the time of surgery, and patchy colitis in the resected colon.

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.

Does a missed obstetric anal sphincter injury at time of delivery affect short-term functional outcome?

Introduction This study aimed to ascertain whether missed obstetric anal sphincter injury at delivery had worse functional and quality of life outcomes than primary repair immediately following delivery. Materials and methods Two to one propensity matching was undertaken of patients presenting to a tertiary pelvic floor unit with ultrasound evidence of missed obstetric anal sphincter injury within 24 months of delivery with patients who underwent primary repair at the time of delivery by parity, grade of injury and time to assessment. Outcomes compared included Birmingham Bowel, Bladder and Urinary Symptom Questionnaire (BBUSQ), Wexner Incontinence Score, Short Form-36, Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire and anorectal physiology results. Results Thirty-two missed anal sphincter injuries were matched two to one with sixty-two patients who underwent primary repair of an anal sphincter defect. Mean time to follow-up was 9.31 ± 6.79 months. Patients with a missed anal sphincter injury had suffered more incontinence, as seen in higher the Birmingham Bowel, Bladder and Urinary Symptom Questionnaire (BBUSQ; 30.56% ± 14.41% vs. 19.75% ± 15.65%, P = 0.002) and Wexner scores (6.00 ± 3.76 vs. 3.67 ± 4.06, P = 0.009). They also had a worse BBUSQ urinary domain score (28.25% ± 14.9% vs. 17.01 ± 13.87%, P = 0.001) and worse physical functioning as measured by the Short Form-36 questionnaire (P = 0.045). There were no differences in other outcomes compared, including anorectal physiology and sexual function. Discussion In the short-term, patients with a missed obstetric anal sphincter injury had significantly worse faecal incontinence and urinary function scores, however quality of life and sexual function were largely comparable between groups. Conclusions Longer-term follow-up is needed to assess the effects of missed obstetric anal sphincter injury over time.

Outcomes with Anti-Tumour Necrosis Factor-Alpha Therapy and Serology in Patients with Denovo Crohn's Disease After Ileal Pouch Anal Anastomosis

BACKGROUND AND AIMS

A subset of patients who undergo ileal pouch-anal anastomosis [IPAA] for ulcerative colitis [UC] will later be diagnosed with denovo Crohn's disease [CD]. These patients have a higher risk of pouch failure. In this study we evaluated inflammatory bowel disease [IBD] serology in patients with denovo CD and examined the success of anti-tumour necrosis factor-alpha [anti-TNFα] therapy in preventing ileostomy in denovo CD patients who failed anti-TNFα therapy before IPAA.

METHODS

A prospectively maintained database of patients undergoing IPAA was reviewed to identify patients who developed denovo CD [defined as small bowel inflammation above the pouch inlet or pouch fistula/perianal disease appearing more than 3 months after stoma closure]. Clinical characteristics and IBD serology were analysed. Treatment failure was defined as pouch failure requiring ileostomy or pouchectomy.

RESULTS

Of 350 patients included in the study, 92 [26%] patients developed denovo CD. Significantly more denovo CD patients had anti-I2 positivity postoperatively versus preoperatively [p = 0.007]. Anti-TNFα therapy successfully treated denovo CD in 28 out of 38 [74%] patients. Out of 17 patients with denovo CD who had failed to respond to anti-TNFα agents before surgery and were treated with anti-TNFα therapy after surgery, 12 [71%] patients responded to treatment.

CONCLUSIONS

I2 serology may possibly help identify patients who have developed or are at risk for developing denovo CD. Anti-TNFα therapy for denovo CD after IPAA can help prevent permanent ileostomy in almost 75% of cases, even in patients who previously failed anti-TNFα treatment before surgery.

Pouchitis Associated With Pelvic Radiation for Prostate Cancer

Radiation therapy is a viable option in managing potentially life-threatening malignancies including prostate cancer. It is known that pelvic radiation can result in injury of the distal large bowel with the development of radiation proctitis. Despite reports from retrospective studies, there is a lack of direct endoscopic and histologic evidence of external pelvic radiation injury to the ileal pouch-anal anastomosis. We present a case of a 68-year-old male with pouchitis resulting from pelvic radiation for prostate cancer.

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.

Crohn's Disease of the Ileoanal Pouch

Crohn's disease (CD) of the pouch is an increasingly recognized diagnosis after ileal pouch-anal anastomosis. This post-ileal pouch-anal anastomosis diagnosis in conjunction with pouchitis remains the leading reason for pouch excision. Unfortunately, CD of the pouch remains a difficult diagnosis with lack of a uniform definition largely because of its similarity to common postoperative pouch complications, including pouchitis, abscess formation, or stricture at the anastomosis. Once diagnosed, treatment algorithms largely include multimodal therapy including biologics. This review focuses on the definition, etiology, diagnosis, and treatment for CD of the pouch, a postoperative de novo diagnosis of CD.

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.

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.

Autoimmunity in Crohn's Disease-A Putative Stratification Factor of the Clinical Phenotype

Inflammation in inflammatory bowel diseases (IBD) has been linked to a loss of tolerance to self-antigens suggesting the existence of autoantibodies in specific disease phenotypes. However, the lack of clearly defined autoantigenic targets has slowed down research. Genome-wide association studies have identified an impressive number of immune-related susceptibility loci for IBD with no clearly discernible pattern among them. Growing evidence supports the hypothesis that innate immune responses to a low-diversity and impaired gut microbiota may be of key importance in initiating and perpetuating chronic inflammation in IBD. Increasing evidence suggests that reduced microbial diversity and microbial-mucosal epithelium interaction (including adhesion and clearance) are critically involved in IBD pathogenesis. Along these lines the discovery of autoantigenic targets in Crohn's disease (CD) has refocused research in IBD on the possible role of autoimmune responses. The identification of the major zymogen granule membrane glycoprotein 2 (GP2) as an autoantigen in CD patients and its proposed role in the sensing of the microbiota lends credence to this trend. Loss of tolerance to GP2 occurs in up to 40% of patients with CD. Corresponding autoantibodies appear to be associated with distinct disease courses (types or phenotypes) in CD. Here, we critically review autoantibodies in CD for their impact on clinical practice and future IBD research. The immunomodulatory role of GP2 in innate and adaptive intestinal immunity is also discussed.

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.

Overcoming difficulty in diagnosis and differential diagnosis of Crohn's disease: the potential role of serological and genetic tests

Crohn's disease (CD) represents a heterogeneous group of chronic inflammatory disorders with various phenotypes. Establishing a definite diagnosis of CD should be based upon a combined assessment of clinical, endoscopic, radiological and pathological features. Although segmental disease distribution, transmural inflammation and non-caseating epithelioid granulomas have been considered as a 'hallmarks' for CD, clear diagnosis of CD in some patients has been challenging, due to overlapping endoscopic, radiographic and histologic features with other inflammatory bowel disease-like conditions. Laboratory markers (serological and genetic tests) may provide additional clues for the diagnosis and differential diagnosis of CD. This review focuses on the application of the currently available serological and genomic markers and in diagnosis and differential diagnosis of CD.

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.

Serological markers associated with disease behavior and response to anti-tumor necrosis factor therapy in ulcerative colitis

BACKGROUND AND AIM

Information is limited on the relationship between serological markers and disease behavior and anti-tumor necrosis factor-α (anti-TNF) therapy response in ulcerative colitis (UC). This study aimed to determine the association between serological markers and unfavorable UC behavior defined as need for colectomy or UC-related hospitalization. The association between serological markers and requirement for and outcome of anti-TNF therapy was also evaluated.

METHODS

Two hundred thirty patients were studied. Requirement for colectomy, UC-related hospitalization, and anti-TNF therapy were documented. Response to anti-TNF therapy at 1 year and rates of therapy discontinuation were recorded. Titers of perinuclear anti-neutrophil cytoplasmic antibodies (pANCAs), anti-Saccharomyces cerevisiae antibody (ASCA), and antibody to Escherichia Coli outer membrane porin (anti-OmpC) were determined. Antibody reference ranges were used to dichotomize subjects into seropositive and seronegative groups. Where multiple tests were performed, P-values were Bonferroni corrected (pcorr).

RESULTS

Extensive colitis was associated with requirement for colectomy and UC-related hospitalization, HR 7.7 (95% confidence interval [CI] 1.9-32.2) pcorr  = 0.03 and HR 2.7 (95% CI 1.5-4.6), pcorr  = 0.006, respectively. No serological variable was associated with unfavorable UC behavior. Anti-OmpC positivity was associated with a lack of response to anti-TNF therapy at 1 year (odds ratio 0.14 [95% CI 0.03-0.60], pcorr  = 0.04) and increased likelihood of therapy discontinuation (HR 2.2 [95% CI 1.1-4.7], P = 0.03).

CONCLUSION

Extensive colitis is associated with unfavorable disease course in UC. Anti-OmpC holds promise as a biomarker of anti-TNF therapy response in UC; however, prospective studies are required before it can be incorporated into routine clinical practice.

Complex host genetics influence the microbiome in inflammatory bowel disease

BACKGROUND

Human genetics and host-associated microbial communities have been associated independently with a wide range of chronic diseases. One of the strongest associations in each case is inflammatory bowel disease (IBD), but disease risk cannot be explained fully by either factor individually. Recent findings point to interactions between host genetics and microbial exposures as important contributors to disease risk in IBD. These include evidence of the partial heritability of the gut microbiota and the conferral of gut mucosal inflammation by microbiome transplant even when the dysbiosis was initially genetically derived. Although there have been several tests for association of individual genetic loci with bacterial taxa, there has been no direct comparison of complex genome-microbiome associations in large cohorts of patients with an immunity-related disease.

METHODS

We obtained 16S ribosomal RNA (rRNA) gene sequences from intestinal biopsies as well as host genotype via Immunochip in three independent cohorts totaling 474 individuals. We tested for correlation between relative abundance of bacterial taxa and number of minor alleles at known IBD risk loci, including fine mapping of multiple risk alleles in the Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) gene exon. We identified host polymorphisms whose associations with bacterial taxa were conserved across two or more cohorts, and we tested related genes for enrichment of host functional pathways.

RESULTS

We identified and confirmed in two cohorts a significant association between NOD2 risk allele count and increased relative abundance of Enterobacteriaceae, with directionality of the effect conserved in the third cohort. Forty-eight additional IBD-related SNPs have directionality of their associations with bacterial taxa significantly conserved across two or three cohorts, implicating genes enriched for regulation of innate immune response, the JAK-STAT cascade, and other immunity-related pathways.

CONCLUSIONS

These results suggest complex interactions between genetically altered host functional pathways and the structure of the microbiome. Our findings demonstrate the ability to uncover novel associations from paired genome-microbiome data, and they suggest a complex link between host genetics and microbial dysbiosis in subjects with IBD across independent cohorts.

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.

Comparison of long-term outcomes of S and J pouches and continent ileostomies in ulcerative colitis patients with restorative proctocolectomy-experience in subspecialty pouch center

BACKGROUND

There are no published studies comparing pouch configurations and long-term adverse outcomes.

AIM

To evaluate outcomes of ulcerative colitis (UC) patients undergoing restorative proctocolectomy with S-, J- pouches or continent ileostomy (CI).

METHODS

We conducted a historical cohort study from the prospectively maintained Pouch Registry. Demographic and clinical variables were evaluated with univariate and multivariable analyses.

RESULTS

Fourty-five patients with S pouches and 36 with CI (33 K pouches and 3 Barnett continent ileal reservoirs) were compared with 215 J pouches serving as controls (ratio 1:2.5). In multivariable analysis, patients with S pouches were 93% less likely to develop chronic antibiotic-refractory pouchitis (CARP) than subjects with J pouches (odds ratio [OR]=0.07; 95% confidence interval: <0.001, 0.54; p<0.001). However, no significant difference in the frequency of CARP was found between the CI and J pouch groups (OR=0.68; 95% confidence interval: 0.17, 2.00, p=0.40). Patients with S pouches were 8 times more likely (95% confidence interval: 3.7, 17.5; p<0.001) and patients with CI 5.6 had times more likely (95% confidence interval: 2.4, 13.3; p<0.001) to have pouch surgery-related complications than those with J pouches. There was no difference in the rate of CD of the pouch, pouch-associated hospitalization and pouch failure between the S- pouch, CI and J- pouch groups.

CONCLUSIONS

Patients with J pouches appeared to have a greater risk for chronic pouchitis than those with S-pouches and but had a lower risk for developing pouch surgery-related complications than those with S pouches or CI.

Ileal pouch symptoms do not correlate with inflammation of the pouch

BACKGROUND & AIMS

Pouchitis is the most common complication after ileal pouch-anal anastomosis (IPAA). However, symptoms are not specific. The Pouchitis Disease Activity Index (PDAI) and the Pouchitis Activity Score (PAS) have been used to diagnose pouchitis. We evaluated the correlation between the clinical components of these scores and endoscopic and histologic findings.

METHODS

We performed a cross-sectional study, analyzing data from 278 patients from Mount Sinai Hospital (Toronto, Canada) who had an IPAA. Patients underwent pouchoscopy with a biopsy, and data were collected on patients' clinical status. The PDAI and PAS were calculated for each subject. The Spearman rank correlation (ρ) statistical test was used to evaluate correlations between the PDAI scores and PAS, and between total scores and subscores.

RESULTS

The total PDAI scores and PAS scores were correlated; the clinical components of each correlated with the total score (ρ = 0.59 and ρ = 0.71, respectively). However, we observed a low level of correlation between clinical and endoscopic or histologic subscores, with ρ of 0.20 and 0.10, respectively, by PDAI, and ρ of 0.19 and 0.04, respectively, by PAS.

CONCLUSIONS

There is a low level of correlation between clinical and endoscopic and histologic subscores of patients with IPAA; clinical symptoms therefore might not reflect objective evidence of inflammation. These findings, along with evidence of correlation between total scores and clinical symptoms, indicate that these indices do not accurately identify patients with pouch inflammation. Further research is required to understand additional factors that contribute to clinical symptoms in the absence of objective signs of pouch inflammation.

Serologic markers associated with development of Crohn's disease after ileal pouch anal anastomosis for ulcerative colitis

BACKGROUND AND AIMS

One of the causes of pouch failure after ileal pouch anal anastomosis (IPAA) for ulcerative colitis (UC) is the development of de novo Crohn's disease (CD). Our aim was to clearly define factors associated with post-IPAA CD.

METHODS

We conducted a cross-sectional study to compare demographic, clinical, and serological characteristics of patients with and without post-IPAA CD. All subjects underwent testing for anti-neutrophil cytoplasm antibodies, anti-Saccaromyces cerevisiae antibodies, anti-outer membrane porin C antibodies, and anti-CBir1 flagellin (anti-CBir1). A multivariable model assessed factors associated with post-IPAA CD.

RESULTS

Thirty-nine subjects were enrolled in the study: 20 cases and 19 controls. Patients who developed post-IPAA CD were significantly younger (median 22 ± 9.9 vs. 30 ± 11.3, p = .027) at the time of UC diagnosis and exhibited more extraintestinal manifestations compared to controls (p = .023). No significant difference between the groups was found with respect to family history, smoking, duration of illness prior to colectomy, time to the onset of pouchitis, preoperative treatment, and indication for surgery. However, the post-operative serologic profile differed significantly with far more cases having elevated anti-CBir1 titers (p = .016, OR 8.81), the latter being the only independent predictor in the combined model.

CONCLUSIONS

Patients with Crohn's disease of the pouch were more likely to have elevated CBir1 antibodies titers than those with simple pouchitis and healthy pouches. The stability of the CBir1 antibodies (pre- and post-colectomy) must be further assessed to establish its value as an independent predictor for development of post-IPAA CD.

Antibodies against glycoprotein 2 are novel markers of intestinal inflammation in patients with an ileal pouch

BACKGROUND AND AIMS

The Crohn's disease (CD)-specific pancreatic auto-antibodies (PAB), have been recently identified to target glycoprotein 2 (GP2). Pouchitis is an inflammation of the small bowel developing in up to 60% of ulcerative colitis patients undergoing proctocolectomy and ileal pouch anal anastomosis. Occurrence of CD-specific antibodies was reported to be a predictor of pouchitis. We aimed to assess the prevalence of anti-GP2 antibodies (anti-GP2) in the serum and feces of pouch patients and to correlate them with clinical parameters. Furthermore, we examined mucosal expression of the GP2 protein in the pouch.

METHODS

Pouch patients were prospectively recruited and checked for clinical, endoscopic, and laboratory markers of inflammation. IgG and IgA anti-GP2 levels in serum and fecal samples were determined using ELISA. GP2 protein was assessed by immunohistochemistry.

RESULTS

Anti-GP2 was elevated in both serum and fecal samples of patients with inflamed compared to those with non-inflamed pouches and patients with familial-adenomatous polyposis after surgery (p<0.05, respectively). Moreover, patients with CD-like complications exhibited significantly higher anti-GP2 titers than those without CD-like complications (p≤0.01). High levels of anti-GP2 correlated with more frequent bowel movements per day and with the presence of at least one anti-glycan antibody (p≤0.05). GP2 itself was more abundant in the mucosa of patients with chronic pouchitis.

CONCLUSIONS

Anti-GP2 exists in the serum and feces of pouch patients and correlates with pouch inflammation, and presence of other serological markers. Thus, anti-GP2 may contribute to better stratification of pouchitis, more-so when the inflammation exhibits CD-like complications.

The NOD2insC polymorphism is associated with worse outcome following ileal pouch-anal anastomosis for ulcerative colitis

BACKGROUND

Inflammatory complications after ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC) are common.

OBJECTIVE

To investigate whether genetic factors are associated with adverse pouch outcomes such as chronic pouchitis (CP) and a Crohn's disease-like (CDL) phenotype.

DESIGN

866 patients were recruited from three centres in North America: Mount Sinai Hospital (Toronto, Ontario, Canada), the Cleveland Clinic (Cleveland, Ohio, USA) and Penn State Milton S Hershey Medical Center (Hershey, Pennsylvania, USA). DNA and clinical and demographic information were collected. Subjects were classified into post-surgical outcome groups: no chronic pouchitis (NCP), CP and CDL phenotype.

RESULTS

Clinical and genetic data were available on 714 individuals. 487 (68.2%) were classified as NCP, 118 (16.5%) CP and 109 (15.3%) CDL. The presence of arthritis or arthropathy (p=0.02), primary sclerosing cholangitis (p=0.009) and duration of time from ileostomy closure to recruitment (p=0.001) were significantly associated with outcome. The NOD2insC (rs2066847) risk variant was the single nucleotide polymorphism (SNP) most significantly associated with pouch outcome (p=7.4×10(-5)). Specifically, it was associated with both CP and CDL in comparison with NCP (OR=3.2 and 4.3, respectively). Additionally, SNPs in NOX3 (rs6557421, rs12661812), DAGLB (rs836518) and NCF4 (rs8137602) were shown to be associated with pouch outcome with slightly weaker effects. A multivariable risk model combining previously identified clinical (smoking status, family history of inflammatory bowel disease), serological (anti-Saccharomyces cerevisiae antibody IgG, perinuclear antineutrophil cytoplasmic antibody and anti-CBir1) and genetic markers was constructed and resulted in an OR of 2.72 (p=8.89×10(-7)) for NCP versus CP/CDL and 3.22 (p=4.11×10(-8)) for NCP versus CDL, respectively.

CONCLUSION

Genetic polymorphisms, in particular, the NOD2insC risk allele, are associated with chronic inflammatory pouch outcomes among patients with UC and IPAA.

Characterization of the gut-associated microbiome in inflammatory pouch complications following ileal pouch-anal anastomosis

Introduction

Inflammatory complications following ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC) are common and thought to arise through mechanisms similar to denovo onset inflammatory bowel disease. The aim of this study was to determine whether specific organisms in the tissue-associated microbiota are associated with inflammatory pouch complications.

Methods

Patients having previously undergone IPAA were recruited from Mount Sinai Hospital. Clinical and demographic information were collected and a pouchoscopy with biopsy of both the pouch and afferent limb was performed. Patients were classified based on post-surgical phenotype into four outcome groups: familial adenomatous polyposis controls (FAP), no pouchitis, pouchitis, and Crohn’s disease-like (CDL). Pyrosequencing of the 16S rRNA V1-V3 hypervariable region, and quantitative PCR for bacteria of interest, were used to identify organisms present in the afferent limb and pouch. Associations with outcomes were evaluated using exact and non-parametric tests of significance.

Results

Analysis at the phylum level indicated that Bacteroidetes were detected significantly less frequently (P<0.0001) in the inflammatory outcome groups (pouchitis and CDL) compared to both FAP and no pouchitis. Conversely, Proteobacteria were detected more frequently in the inflammatory groups (P=0.01). At the genus level, organisms associated with outcome were detected less frequently among the inflammatory groups compared to those without inflammation. Several of these organisms, including Bacteroides (P<0.0001), Parabacteroides (P≤2.2x10^-3), Blautia (P≤3.0x10^-3) and Sutterella (P≤2.5x10^-3), were associated with outcome in both the pouch and afferent limb. These associations remained significant even following adjustment for antibiotic use, smoking, country of birth and gender. Individuals with quiescent disease receiving antibiotic therapy displayed similar reductions in these organisms as those with active pouch inflammation.

Conclusions

Specific genera are associated with inflammation of the ileal pouch, with a reduction of typically ubiquitous organisms characterizing the inflammatory phenotypes.

Personalizing therapy for inflammatory bowel diseases

Inflammatory bowel diseases (IBDs; e.g., Crohn's disease [CD] and ulcerative colitis [UC]) are chronic immunologically mediated diseases characterized by frequent relapses, often requiring hospitalization and surgery. There is substantial heterogeneity in the progressive natural history of disease with cumulative accrual of bowel damage and impairment of functioning. Recent advances in therapeutics have significantly improved our ability to achieve disease remission; yet therapies remain expensive and are associated with significant side effects precluding widespread use in all patients with IBD. Consequently, algorithms for the management of patients with IBD require a personalized approach incorporating an individual's projected likely natural history, the probability of response to a specific therapeutic agent and an informed approach to management of loss of response to current therapies.

Glycoprotein 2 antibodies in Crohn's disease

The pathogenesis of Crohn's disease (CrD) and ulcerative colitis (UC), the two major inflammatory bowel diseases (IBD), remains poorly understood. Autoimmunity is considered to be involved in the triggering and perpetuation of inflammatory processes leading to overt disease. Approximately 30% of CrD patients and less than 8% of UC patients show evidence of humoral autoimmunity to exocrine pancreas, detected by indirect immunofluorescence. Pancreatic autoantibodies (PAB) were described for the first time in 1984, but the autoantigenic target(s) of PABs were identified only in 2009. Utilizing immunoblotting and matrix-assisted laser desorption ionization time-of-flight mass spectrometry, the major zymogen granule membrane glycoprotein 2 (GP2) has been discovered as the main PAB autoantigen. The expression of GP2 has been demonstrated at the site of intestinal inflammation, explaining the previously unaddressed contradiction of pancreatic autoimmunity and intestinal inflammation. Recent data demonstrate GP2 to be a specific receptor on microfold (M) cells of intestinal Peyer's patches, which are considered to be the original site of inflammation in CrD. Novel ELISAs, employing recombinant GP2 as the solid phase antigen, have confirmed the presence of IgA and IgG anti-GP2 PABs in CrD patients and revealed an association of anti-GP2 IgA as well as IgG levels with a specific clinical phenotype in CrD. Also, GP2 plays an important role in modulating innate and acquired intestinal immunity. Its urinary homologue, Tamm-Horsfall protein or uromodulin, has a similar effect in the urinary tract, further indicating that GP2 is not just an epiphenomenon of intestinal destruction. This review discusses the role of anti-GP2 autoantibodies as novel CrD-specific markers, the quantification of which provides the basis for further stratification of IBD patients. Given the association with a disease phenotype and the immunomodulating properties of GP2 itself, an important role for GP2 in the immunopathogenesis of IBD cannot be excluded.

Ethnicity and the risk of development of Crohn's disease of the ileal pouch

BACKGROUND

A system-wide, multi-ethnicity study on Crohn's disease (CD) of the pouch, including Indian American (IA) patients has not been conducted.

AIM

To compare the frequency of subsequent development of CD of the pouch for African-American (AA), Hispanic-American (HA), IA and Caucasian patients with ulcerative (UC) undergoing ileal-pouch anal anastomosis (IPAA).

METHODS

In this historical cohort study from our Pouch Registry, patients with restorative proctocolectomy and IPAA for IBD with identifiable, self-declared racial background (i.e. AA, HA, IA or Caucasian) were included. Univariable and multivariable analyses were performed to identify risk factors for CD of the pouch.

RESULTS

The study included 235 patients: AA (N=26), HA (N=37), IA (N=22) and randomly selected Caucasian (N=150) controls. Greater number of HA and Caucasians had a history of smoking than IA (27.3% and 27.0% vs. 0; p=0.007). Caucasians and HA were also more likely to have a family history of IBD than IA or AA (25% vs. 27% vs. 5% vs. 4%; p=0.016.) IA less frequently had extensive colitis before colectomy than Caucasians (71.4% vs. 94.0%; p=0.004) and more frequently required anti-TNF biologics than HA (22.7% vs. 0; p=0.016). On multivariable logistic regression analysis, AA (odds ratio [OR]=10.1, 95% confidence interval [CI]: 1.03, 1365.8, p=0.004) and Caucasians (OR=11.1, 95% CI: 1.4, 1427.2, p=0.015) had a higher risk of developing CD of the pouch than IA. However, the event-free survival was not significantly different between the groups on Cox regression analysis, presumably due to the sample size.

CONCLUSION

Racial background may be associated with different risk for the development of CD of the pouch for patients with IBD undergoing IPAA.

The presence of primary sclerosing cholangitis is protective for ileal pouch from Crohn's disease

BACKGROUND

Primary sclerosing cholangitis (PSC) has been shown to increase the risk for chronic pouchitis. However, the association between PSC and Crohn's disease (CD) of the pouch has not been studied.

METHODS

Consecutive inflammatory bowel disease patients undergoing proctocolectomy with ileal pouch-anal anastomosis in our Pouchitis Registry from 2002 to 2012 were studied. Cases consisted of patients with CD of the pouch. Both univariable and multivariable analyses were performed.

RESULTS

A total of 1425 patients met the inclusion criteria, including 265 (18.6%) with CD of the pouch and 78 (5.5%) with PSC. In the whole cohort, 799 patients (56.1%) were male and the mean ages at the time of diagnosis of inflammatory bowel disease and at pouch surgery were 25.5 ± 12.3 years and 35.4 ± 13.9 years, respectively. Patients with PSC had a longer duration from inflammatory bowel disease diagnosis to pouch construction (P < 0.001). Fewer patients with PSC had toxic megacolon at the time of colectomy (P = 0.009), but more patients with PSC had neoplasia as the indication for colectomy (P < 0.001), concurrent autoimmune disorders (P < 0.001), and liver transplantation (P = 0.001). In the multivariate analysis, the presence of PSC was shown to be inversely associated with the risk for the development of CD of the pouch, with a hazard ratio of 0.39 (95% confidence interval: 0.16 to 0.95, P = 0.038). However, no significant difference in terms of the distribution of phenotypes of CD of the pouch between patients with and without PSC was identified (P = 0.59).

CONCLUSIONS

The presence of PSC is inversely associated with the development of CD of the pouch.

Meta-analysis: serological markers and the risk of acute and chronic pouchitis

BACKGROUND

Serological markers such as anti-neutrophil cytoplasmic antibody (ANCA) and anti-Saccharomyces cerevisiae antibody (ASCA) may be associated with pouchitis after ileal pouch-anal anastomosis (IPAA).

AIM

To perform a systematic review with meta-analysis of studies evaluating the association of ANCA and ASCA status with risk of acute and chronic pouchitis after IPAA.

METHODS

We searched multiple databases (upto September 2012) for studies reporting ANCA and/or ASCA status along with risk of acute or chronic pouchitis after IPAA in adults with ulcerative colitis (UC). We abstracted odds ratio (OR) or raw data from the individual studies to calculate summary OR estimates with 95% CIs using random-effects model.

RESULTS

Eight studies reporting 184 cases of acute pouchitis and six studies reporting 151 cases of chronic pouchitis were included. The odds of chronic pouchitis were 76% higher in ANCA-positive patients than ANCA-negative (six studies; OR: 1.76; 95% CI: 1.19-2.61; P < 0.01). ASCA-positivity was not associated with the risk of chronic pouchitis (three studies; OR: 0.89; 95% CI: 0.49-1.59; P = 0.68). Neither ANCA (eight studies; OR: 1.54; 95% CI: 0.79-3.02; P = 0.21) nor ASCA-positivity (two studies; OR: 1.28; 95% CI: 0.25-6.54; P = 0.77) were associated with the risk of acute pouchitis.

CONCLUSIONS

The risk of chronic pouchitis after IPAA is higher in ANCA-positive patients, but the risk of acute pouchitis is unaffected by ANCA status. ASCA status was not associated with the risk of acute or chronic pouchitis. This information may be used to counsel UC patients regarding their risk of pouchitis after IPAA.

Diagnosis and differential diagnosis of Crohn's disease of the ileal pouch

Approximately 20%-30% of patients with ulcerative colitis will eventually require colectomy despite recent advances in medical therapy. Ileal pouch-anal anastomosis has become the surgical treatment of choice. A subset of patients with ileal pouches can develop Crohn's disease or a Crohn's-disease-like condition of the ileal pouch after surgery. Diagnosis, differential diagnosis, and management of Crohn's disease of the ileal pouch have been challenging. A combined assessment of clinical history, endoscopy, histology, abdominal/pelvic imaging, and examination under anesthesia is often necessary for accurate diagnosis, disease classification, management, and prognosis. A multidisciplinary approach with gastroenterologists, colorectal surgeons, gastrointestinal pathologists, and radiologists is advocated.

Have genomic discoveries in inflammatory bowel disease translated into clinical progress?

Inflammatory bowel disease (IBD) is a heterogeneous disease that can be challenging to diagnose and manage. As a result, significant efforts have been made in attempting to identify clinical, genomic, and serologic markers of disease that can aid in patient assessment and treatment. Recent genomic discoveries have the potential to change clinical practice by identifying those susceptible to IBD, predict natural history and guide choice of therapy. Panels of genetic and genomic markers are more likely to emerge as clinical tools, as opposed to individual allelic variants. Serology and biomarkers are already being used and guiding management but await integration with genomic panels before achieving their maximal potential. This article reviews the current state of IBD genetics and evolving molecular approaches that may have potential clinical impact.

Evaluating pouch problems

IPAA is a technically demanding procedure that requires appropriate skills and expertise. Adverse sequelae of IPAA are common. Accurate diagnosis and classification of pouch disorders and associated complications are important for proper management and prognosis. Based on presenting symptoms, appropriate and combined diagnostic modalities should apply. A multidisciplinary approach involving gastroenterologists, colorectal surgeons, gastrointestinal pathologists, and gastrointestinal radiologists is advocated for diagnosis and treatment of pouch disorders.