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

AGA Clinical Practice Guideline on the Management of Pouchitis and Inflammatory Pouch Disorders

BACKGROUND & AIMS

Pouchitis is the most common complication after restorative proctocolectomy with ileal pouch-anal anastomosis for ulcerative colitis. This American Gastroenterological Association (AGA) guideline is intended to support practitioners in the management of pouchitis and inflammatory pouch disorders.

METHODS

A multidisciplinary panel of content experts and guideline methodologists used the Grading of Recommendations Assessment, Development and Evaluation framework to prioritize clinical questions, identify patient-centered outcomes, conduct an evidence synthesis, and develop recommendations for the prevention and treatment of pouchitis, Crohn's-like disease of the pouch, and cuffitis.

RESULTS

The AGA guideline panel made 9 conditional recommendations. In patients with ulcerative colitis who have undergone ileal pouch-anal anastomosis and experience intermittent symptoms of pouchitis, the AGA suggests using antibiotics for the treatment of pouchitis. In patients who experience recurrent episodes of pouchitis that respond to antibiotics, the AGA suggests using probiotics for the prevention of recurrent pouchitis. In patients who experience recurrent pouchitis that responds to antibiotics but relapses shortly after stopping antibiotics (also known as "chronic antibiotic-dependent pouchitis"), the AGA suggests using chronic antibiotic therapy to prevent recurrent pouchitis; however, in patients who are intolerant to antibiotics or who are concerned about the risks of long-term antibiotic therapy, the AGA suggests using advanced immunosuppressive therapies (eg, biologics and/or oral small molecule drugs) approved for treatment of inflammatory bowel disease. In patients who experience recurrent pouchitis with inadequate response to antibiotics (also known as "chronic antibiotic-refractory pouchitis"), the AGA suggests using advanced immunosuppressive therapies; corticosteroids can also be considered in these patients. In patients who develop symptoms due to Crohn's-like disease of the pouch, the AGA suggests using corticosteroids and advanced immunosuppressive therapies. In patients who experience symptoms due to cuffitis, the AGA suggests using therapies that have been approved for the treatment of ulcerative colitis, starting with topical mesalamine or topical corticosteroids. The panel also proposed key implementation considerations for optimal management of pouchitis and Crohn's-like disease of the pouch and identified several knowledge gaps and areas for future research.

CONCLUSIONS

This guideline provides a comprehensive, patient-centered approach to the management of patients with pouchitis and other inflammatory conditions of the pouch.

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.

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.

Treatment Patterns and Standardized Outcome Assessments Among Patients With Inflammatory Conditions of the Pouch in a Prospective Multicenter Registry

Background

Much of our understanding about the natural history of pouch-related disorders has been generated from selected populations. We designed a geographically diverse, prospective registry to study the disease course among patients with 1 of 4 inflammatory conditions of the pouch. The primary objectives in this study were to demonstrate the feasibility of a prospective pouch registry and to evaluate the predominant treatment patterns for pouch-related disorders.

Methods

We used standardized diagnostic criteria to prospectively enroll patients with acute pouchitis, chronic antibiotic-dependent pouchitis (CADP), chronic antibiotic refractory pouchitis (CARP), or Crohn’s disease (CD) of the pouch. We obtained detailed clinical and demographic data at the time of enrollment, along with patient-reported outcome (PRO) measures.

Results

We enrolled 318 patients (10% acute pouchitis, 27% CADP, 12% CARP, and 51% CD of the pouch). Among all patients, 55% were on a biologic or small molecule therapy. Patients with CD of the pouch were more likely to use several classes of therapy (P < .001). Among patients with active disease at the time of enrollment, 23% with CARP and 40% with CD of the pouch were in clinical remission at 6 months after enrollment.

Conclusions

In a population where most patients had refractory inflammatory conditions of the pouch, we established a framework to evaluate PROs and clinical effectiveness. This infrastructure will be valuable for long-term studies of real-world effectiveness for pouch-related disorders.

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.

Clinical Discrimination of Chronic Pouchitis After Ileal Pouch-Anal Anastomosis in Patients with Ulcerative Colitis

PURPOSE

We aimed to identify predictive factors for the development of chronic pouchitis after ileal pouch-anal anastomosis in patients with ulcerative colitis.

METHODS

Three hundred eighty-seven patients who underwent ileal pouch-anal anastomosis for diagnosis of ulcerative colitis from January 2002 to March 2019 were included in this retrospective analysis.

RESULTS

Of 115 patients with pouchitis, 40 patients exhibited acute pouchitis, and 75 patients exhibited chronic pouchitis. Of 75 patients with chronic pouchitis, 11 patients were diagnosed with chronic antibiotic-refractory pouchitis. Multivariate analysis revealed that early pouchitis onset and modified Pouchitis Disease Activity Index score ≥ 7 were independent predictive factors for chronic pouchitis (p = 0.0004 and p = 0.029, respectively). Mean onset of pouchitis after intestinal continuity was significantly earlier in patients with chronic pouchitis than in patients with acute pouchitis (acute pouchitis vs. chronic pouchitis: 3.72 ± 2.98 years vs. 1.85 ± 2.40 years, p < 0.0001). Total modified Pouchitis Disease Activity Index score was significantly higher in patients with chronic pouchitis than in patients with acute pouchitis (acute pouchitis vs. chronic pouchitis: 5.9 ± 1.2 vs. 6.9 ± 1.6, p = 0.0020).

CONCLUSION

Patients with ulcerative colitis were more likely to develop chronic pouchitis if they exhibited early onset or severe disease activity at onset. Evaluation of both factors can aid in early treatment decisions to alleviate chronic pouchitis.

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.

Chronic Antibiotic-Refractory Pouchitis: Management Challenges

Background

Pouchitis is the most common long-term complication in patients with ulcerative colitis who underwent restorative proctocolectomy with ileal pouch-anal anastomosis. The incidence of acute pouchitis is 20% after 1 year and up to 40% after 5 years. Chronic antibiotic-refractory pouchitis develops in approximately 10% of patients.

Aim

To present a narrative review of published literature regarding the management of chronic antibiotic-refractory pouchitis.

Methods

Current relevant literature was summarized and critically evaluated.

Results

Clear definitions should be used to classify pouchitis into acute versus chronic, and responsive versus dependent versus refractory to antibiotics. Before treatment is started for chronic antibiotic-refractory pouchitis, secondary causes should be ruled out. There is a need for validated scoring systems to measure the severity of the disease. Because chronic antibiotic-refractory pouchitis is a rare condition, only small studies with often a poor study design have been performed. Treatments with antibiotics, aminosalicylates, steroids, immunomodulators and biologics have shown to be effective and safe for chronic antibiotic-refractory pouchitis. Also, treatments with AST-120, hyperbaric oxygen therapy, tacrolimus enemas, and granulocyte and monocyte apheresis suggested some efficacy.

Conclusion

The available data are weak but suggest that therapeutic options for chronic antibiotic-refractory pouchitis are similar to the treatment strategies for inflammatory bowel diseases. However, randomized controlled trials are warranted to further identify the best treatment options in this patient population.

Pouchitis in inflammatory bowel disease: a review of diagnosis, prognosis, and treatment

Patients with inflammatory bowel disease (IBD) occasionally need a restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) because of medically refractory colitis or dysplasia/cancer. However, pouchitis may develop in up to 70% of patients after this procedure and significantly impair quality of life, more so if the inflammation becomes a chronic condition. About 10% of patients with IBD who develop pouchitis require pouch excision, and several risk factors of the failure have been reported. A phenotype that has features similar to Crohn’s disease may develop in a subset of ulcerative colitis patients following proctocolectomy with IPAA and is the most frequent reason for pouch failure. In this review, we discuss the diagnosis and prognosis of pouchitis, risk factors for pouchitis development, and treatment options for pouchitis, including the newer biological agents.

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: diagnosis and management

PURPOSE OF REVIEW

Pouchitis is the most common complication in patients who undergo ileal pouch-anal anastomosis (IPAA), occurring more frequently in patients with ulcerative colitis. Pouchitis - the inflammation of the pouch - can be due to idiopathic or secondary causes. Chronic antibiotic-dependent pouchitis (CADP) and chronic antibiotic-resistant pouchitis (CARP) are the most difficult forms of chronic idiopathic pouchitis to treat. Crohn's disease of the pouch may develop de novo in ulcerative colitis patients following colectomy with IPAA. It carries a high risk for pouch failure, and its diagnosis and management are challenging. The purpose of this review is to illustrate the present trends in the diagnosis and treatment of idiopathic pouchitis and Crohn's disease of the pouch.

RECENT FINDINGS

The use of the newer biologic agents, vedolizumab and ustekinumab, has shown promising results in patients with CADP, CARP, and Crohn's disease of the pouch. Fecal microbiota transplantation has also been reported to have encouraging preliminary results in small studies and case series for the treatment of chronic pouchitis.

SUMMARY

Promising new treatments are emerging for difficult-to-treat forms of pouchitis. Larger prospective and head-to-head comparative studies among the various treatments are needed to evaluate the efficacy and safety of these agents across the pouchitis subgroups, and to identify predictors of response.

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.

Effective Use of the Laboratory in the Management of Patients with Inflammatory Bowel Diseases

Inflammatory bowel disease (IBD) comprises a group of chronic, intestinal inflammatory disorders, including ulcerative colitis and Crohn's disease. IBD is characterized by periods of relapse and remission. Long-term progressive intestinal inflammation can result in severe and devastating complications, such as intestinal strictures and/or fistulae. Immune suppressive medications with potent side effects are often used to control inflammation and limit disease activity. Laboratory tests guide various decisions in clinical management of IBD. We discuss tests used to diagnose IBD, assess for relapse or remission, monitor the effectiveness of therapeutic regimen, screen for the maintenance of health, and diagnose or prevent complications.

Meta-analysis of the association of extraintestinal manifestations with the development of pouchitis in patients with ulcerative colitis

Background

The presence of extraintestinal manifestations may be associated with the development of pouchitis in patients with ulcerative colitis after ileal pouch–anal anastomosis. The aim of this study was to assess this correlation.

Methods

A systematic literature search was performed using MEDLINE and the Cochrane Library. Studies published in English up to 22 May 2017 investigating the association between extraintestinal manifestations and development of pouchitis in adults with ulcerative colitis were included. Case reports were excluded. The association of extraintestinal manifestations with the development of overall and chronic pouchitis was investigated using a random‐effects model.

Results

Of 1010 citations identified, 22 observational studies comprising 5128 patients were selected for analysis. The presence of extraintestinal manifestations was significantly associated with both chronic pouchitis (odds ratio 2·28, 95 per cent c.i. 1·57 to 3·32; P = 0·001) and overall pouchitis (odds ratio 1·96, 1·49 to 2·57; P < 0·001).

Conclusion

The presence of extraintestinal manifestations is associated with development of pouchitis after ileal pouch–anal anastomosis.

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.

A Personalized Approach to Managing Patients With an Ileal Pouch-Anal Anastomosis

Quality of life after ileal pouch-anal anastomosis (IPAA) surgery is generally good. However, patients can be troubled by pouch-related symptoms and pouch disorders that can be inflammatory, mechanical/surgical, and functional. Management of patients with IPAA begins with measures to maintain a healthy pouch such as optimizing pouch function, providing tailored advice on a healthy diet and lifestyle, screening for and addressing metabolic complications of IPAA, pouch surveillance, and risk stratification for risk of pouchitis and pouch failure. Pouchitis is the most common inflammatory disorder. Primary pouchitis is a spectrum currently classified into three progressive phases-an antibiotic-responsive, an antibiotic-dependent, and an antibiotic-refractory phase. It is predominately microbially mediated in acute antibiotic-responsive pouchitis and predominately immune mediated in chronic antibiotic-refractory pouchitis (CARP). Secondary prophylaxis is recommended for recurrent antibiotic-responsive and for antibiotic-dependent pouchitis. Secondary causes of antibiotic-refractory pouchitis should be ruled out before a diagnosis of CARP is made. CARP is best classified as primary sclerosing cholangitis associated, immunoglobulin G4-associated, and autoimmune. Primary sclerosing cholangitis-associated CARP can be treated with budesonide or oral vancomycin. Early recognition of immunoglobulin G4-associated pouchitis minimizes ineffective antibiotic use. Autoimmune CARP can be managed in a manner similar to UC. The current place of immunosuppressives in the treatment algorithm depends on availability and early access to biological agents. Vedolizumab and ustekinumab are the preferred first- and second-line biologics for autoimmune CARP owing to their efficacy, better side effect profile, and low immunogenicity and need for concomitant immunomodulatory therapy. Antitumor necrosis factor should be reserved for autoimmune CARP failing the above and for CD of the pouch. There are no guidelines for the surveillance of pouches for dysplasia. Incidence varies based on a patient's risk. Since incidence is low, a risk-stratified approach is recommended.

Use of biomarkers in inflammatory bowel disease

There are many useful biomarkers for initial diagnosis and the management of inflammatory bowel disease. Serologic biomarkers have been traditionally used because they are widely disposable, but recently faecal biomarkers, especially faecal calprotectin, have acquired great importance as they have shown to be more precise when establishing suspicion of the disease and also as predictors of mucosal healing or persistence of inflammatory activity. Faecal calprotectin is a good tool for predicting abnormal endoscopic studies, but has limited specificity because its levels can be altered in many digestive diseases presenting with similar symptoms. The precision of faecal calprotectin is higher when associated with other altered parameters, especially with C-reactive protein, or with clinical scores of inflammatory activity. Finally, there are many new generation serologic and faecal biomarkers. Despite there not being much evidence about these yet, some of them have shown promising results in different studies.

Molecular diagnosis and classification of inflammatory bowel disease

INTRODUCTION

Traditional diagnosis and classification of inflammatory bowel diseases (IBDs) have been based on clinical evaluation, laboratory testing, endoscopy, imaging, and histological examinations. With the advancement of medical technology, an increasing number of molecular surrogates are playing a key role in diagnosis, differential diagnosis, assessment of disease activity, prediction of clinical course, and therapeutic response of IBD. Areas covered: The authors review roles of both existing and emerging surrogates including genetic, serological, histologic, and fecal markers in diagnosis and classification of IBD. Comparisons in advantages and disadvantages of different markers have also been discussed. In addition, this review underscores controversial and unclear aspects which need further study. Expert commentary: IBD is characteristic of chronicity, relapse-remission and destructiveness. It is of great importance for clinicians to make an accurate diagnosis and classification. Current and new molecular markers perform well with acceptable sensitivity and specificity. The use of molecular markers in clinical practice needs to be further explored and then generalized. More work is warranted to identify novel useful markers and elucidate how to apply them together with current markers in clinical settings.

Management of Pouchitis and Other Common Complications of the Pouch

Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) has become the preferred surgical treatment for refractory or complicated ulcerative colitis (UC) and familial adenomatous polyposis (FAP). Pouchitis is the most common complication of this procedure and can occur in about 50% of patients. Treatment of pouchitis depends on the phenotype of disease. Pouchitis can be classified as acute, chronic/refractory, or secondary pouchitis, which includes pouchitis occurring due to Crohn's disease (CD). CD of the pouch is becoming an increasingly recognized problem, and management is challenging. This article reviews the literature and offers treatment recommendations regarding management of pouchitis and CD of the pouch.

Abdominal Visceral Fat Area and Chronic Pouchitis after Ileal Pouch-Anal Anastomosis

Chronic pouchitis (CP) after ileal pouch-anal anastomosis is a significant clinical problem. Adipose tissues produce antiinflammatory cytokines and chemokines. We evaluated the association between abdominal visceral fat area (VFA) and CP. Patients with a preoperative CT evaluation were included. The diagnosis of CP was confirmed in all cases by endoscopy with afferent ileal limb intubation. Patients were allocated into groups of high VFA and low VFA. The study cohort of 52 patients had a median body mass index of 22 (range, 14–32). Indications for surgery were medically refractory disease in 46 (88%) patients and cancer/dysplasia in six (12%) patients. Median VFA was 27.1 (range, 1–144). Six (12%) patients developed CP. Low VFA patients were significantly younger (29 vs 45 years; P < 0.0001), had lower body mass index (20.4 vs 24.7; P < 0.0001), had surgery more commonly for medically refractory disease than for cancer or dysplasia (100 vs 77%; P = 0.02), and had a higher incidence of CP than high VFA patients (23 vs 0%; P = 0.02). Multiple linear regression analysis demonstrated that only low VFA was associated with CP (P = 0.009). An association is present between VFA and CP after ileal pouch-anal anastomosis, implicating adipocytes in the pathogenesis of inflammatory bowel disease.

Clinical usefulness of serum antibodies as biomarkers of gastrointestinal and liver diseases

The progressively growing knowledge of the pathophysiology of a number of immune-mediated gastrointestinal and liver disorders, including autoimmune atrophic gastritis, coeliac disease, autoimmune enteropathy, inflammatory bowel disease, autoimmune hepatitis, primary sclerosing cholangitis, primary biliary cholangitis and autoimmune pancreatitis, together with the improvement of their detection methods have increased the diagnostic power of serum antibodies. In some cases - coeliac disease and autoimmune atrophic gastritis - they have radically changed gastroenterologists' diagnostic ability, while in others - autoimmune hepatitis, inflammatory bowel disease and autoimmune pancreatitis - their diagnostic performance is still inadequate. Of note, serum antibody misuse in clinical practice has raised a number of controversies, which may generate confusion in the diagnostic management of the aforementioned disorders. In this review, we critically re-evaluate the usefulness of serum antibodies as biomarkers of immune-mediated gastrointestinal and liver disorders, and discuss their pitfalls and merits.

The outcome of ulcerative colitis patients undergoing pouch surgery is determined by pre-surgical factors

BACKGROUND

Pouch surgery, a common intervention for ulcerative colitis (UC) complications, is often associated with the development of pouchitis.

AIM

To identify predictors of pouch outcome in a cohort of patients with UC.

METHODS

We conducted a retrospective unmatched case-cohort study in a tertiary IBD referral centre. Adult patients with UC were classified into the worst phenotype throughout follow-up: normal pouch, a form of chronic pouchitis (either chronic pouchitis or Crohn's like disease of pouch [CLDP]), or episodic recurrent acute pouchitis (RAP). Risk factors for pouchitis (chronic forms) were detected using statistical models.

RESULTS

Two hundred and fifty-three pouch patients were followed up for 13.1±7.3 years. Only 71 patients (28.1%) maintained a favourable outcome of a sustained normal pouch. These patients were older at UC diagnosis (27.8±12.5 vs 23.0±11.4 years), had longer UC duration until surgery (13.4±9.5 vs 8.2±7.9 years), and had higher rates of referral to surgery due to nonrefractory (dysplasia/neoplasia) complications (42.3% vs 16.2%) compared with pouchitis patients. Median survival for sustained normal pouch was 10.8 years (95% CI 8.9-12.7 years), and it was longer in the nonrefractory group (20.3 vs 9.4 years for the refractory group, HR=2.37, 95% CI 1.25-3.52, P=.004).

CONCLUSIONS

Most patients with UC undergoing pouch surgery will develop pouchitis. Patients operated for nonrefractory indications have a more favourable outcome. These results may contribute to pre- and post-surgical decision-making. The findings imply that the processes determining UC severity may be similar to that causing pouchitis.

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.

Complementary and Alternative Medicines Used by Patients With Inflammatory Bowel Diseases

Patients and physicians often have many questions regarding the role of complementary and alternative medicines (CAMs), or nonallopathic therapies, for inflammatory bowel diseases (IBDs). CAMs of various forms are used by more than half of patients with IBD during some point in their disease course. We summarize the available evidence for the most commonly used and discussed CAMs. We discuss evidence for the effects of herbs (such as cannabis and curcumin), probiotics, acupuncture, exercise, and mind-body therapy. There have been few controlled studies of these therapies, which have been limited by their small sample sizes; most studies have been uncontrolled. In addition, there has been a lack of quality control for herbal preparations. It has been a challenge to design rigorous, randomized, placebo-controlled trials, in part owing to problems of adequate blinding for psychological interventions, acupuncture, and exercise. These barriers have limited the acceptance of CAMs by physicians. However, such therapies might be used to supplement conventional therapies and help ease patient symptoms. We conclude that physicians should understand the nature of and evidence for CAMs for IBD so that rational advice can be offered to patients who inquire about their use. CAMs have the potential to aid in the treatment of IBD, but further research is needed to validate these approaches.

Pouchitis after ileal pouch-anal anastomosis in ulcerative colitis: Diagnosis, management, risk factors, and incidence

Restorative proctocolectomy with ileal pouch-anal anastomosis has been the surgical treatment of choice for patients with ulcerative colitis who require surgery. Quality of life after this procedure is satisfactory in most cases; however, pouchitis is a troublesome condition involving inflammation of the ileal pouch. When a patient presents with symptoms of pouchitis, such as increased bowel movements, mucous and/or bloody exudates, abdominal cramps, and fever, endoscopy is essential for a precise diagnosis. The proximal ileum and rectal cuff, as well as the ileal pouch, should be endoscopically observed. The reported incidence of pouchitis ranges from 14% to 59%, and antibiotic therapy is the primary treatment for acute pouchitis. Chronic pouchitis includes antibiotic-dependent and refractory pouchitis. Intensive therapy including antitumor necrosis factor antibodies and steroids may be necessary for antibiotic-refractory pouchitis, and pouch failure may occur despite such intensive treatment. Reported risk factors for the development of pouchitis include presence of extraintestinal manifestations, primary sclerosing cholangitis, non-smoking, and postoperative non-steroidal anti-inflammatory drug usage. In the present review, we focus on the diagnosis, endoscopic features, management, incidence, and risk factors of pouchitis in patients with ulcerative colitis who underwent ileal pouch-anal anastomosis.

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.

Update on the pathogenesis and management of pouchitis

Pouchitis is an inflammatory complication after restorative proctocolectomy and ileal pouch-anal anastomosis (IPAA). IPAA is the surgical treatment of choice in patients with ulcerative colitis (UC) who require colectomy. Initial episodes of acute pouchitis generally respond to antibiotics but significant numbers of cases eventually become dependent on or refractory to antibiotics. Management of chronic antibiotic refractory pouchitis is challenging and can ultimately lead to pouch failure. The etiopathogenesis is unknown though recent studies have implicated bacterial dysbiosis of the pouch microbiota, NOD2 polymorphism, and Clostridium difficile infection in the development of severe pouchitis. Early identification of risk factors can help in tailoring therapy and reducing cases of chronic pouchitis.

Reduced neurons in the ileum of proctocolectomized rat models

Ileal pouch-anal anastomosis (IPAA) is the operation of choice following proctocolectomy for patients who suffer from ulcerative colitis and familial adenomatous polyposis. The aim of this study was to morphologically examine the neurons, endocrine cells and mast cells in the ileum of rats subjected to proctocolectomy followed by three different types of ileoanal anastomosis. Rats were subjected to either sham operation or proctocolectomy followed by ileoanal anastomosis end-to-end, side-to-end or IPAA (J-pouch). In comparison to sham-operated rats, the body weight was reduced in rats that underwent proctocolectomy with end-to-end or side-to-end, but not IPAA procedure. In all three models of ileoanal anastomosis, the ileum displayed crypt hyperplasia with a chronic inflammatory infiltrate located in the interstitium, hyperplasia of goblet cells, but reduced protein gene product 9.5 (PGP 9.5)-immunoreactive neurons in the mucosa as well as submucosa. Numbers of endocrine cells in the mucosa (chromogranin A immunostaining) and mast cells in the mucosa and submucosa (Astra blue staining) were unchanged after proctocolectomy. In conclusion, neurons, but neither endocrine cells nor mast cells, were reduced in the ileum of proctocolectomized rats followed by either of three different types of ileoanal anastomosis.

Managing intractable proctitis and the problematic pouch

Proctitis accounts for a significant proportion of cases of ulcerative colitis (UC), and some patients subsequently develop more extensive disease. However, most patients continue to have limited inflammation, although the changes in the distal colon and rectum can occasionally be severe, and symptoms of increased frequency, rectal bleeding and urgency can be as disabling as they are for patients with more extensive colitis. Furthermore, although symptoms are typically well controlled with standard medications, medically refractory proctitis poses particular problems. Patients generally are not systemically unwell, and there is no added fear of cancer. Therefore, the prospect of colectomy for such limited disease is resisted by patients, physicians and surgeons alike. Unusual therapies, often delivered locally by enema or suppository, have been tested in small case series without definitive outcomes. The pathogenesis of such limited, yet intractable inflammation remains unclear, and the differential diagnosis should be carefully reviewed to ensure that local disease, whether it is infectious, vascular, or a result of injury or degeneration, is not overlooked. Ileo-anal pouch formation is the surgery of choice for about 20% of patients with UC who undergo colectomy. In the majority of cases, this surgery results in an acceptable quality of life and freedom from a stoma. However, in a sizeable minority of cases, pouch dysfunction can cause intractable problems. The causes of pouch dysfunction are varied and must all be considered carefully, particularly in refractory cases. Pouchitis is a common issue and is usually transient and easily treated. However, refractory and chronic pouchitis can be challenging. Ischaemia, injury, infection and Crohn's disease can all cause refractory pouch dysfunction. In a minority of cases, there appears to be no apparent organic pathology, and the presumptive diagnosis is that of a functional pouch disorder. Although it is much rarer, neoplastic changes in the pouch must also be considered, and the risk managed appropriately. The management of both intractable proctitis and the problematic pouch is made more challenging by the wide differential diagnosis that must be considered and by the paucity of high-quality clinical trials to support any one therapy. Key strategies to overcoming these limitations include methodical and systematic investigation and review, and a willingness to tailor therapy to the individual patient. Clinical trials of new treatments should be supported, and data from the experience with small cohorts of patients should be meticulously collected, critically analysed and widely disseminated.

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.