Are Small Molecules Effective in Treating Inflammatory Pouch Disorders Following Ileal Pouch-Anal Anastomosis for Ulcerative Colitis? Here Is Where We Stand.

Ulcerative colitis (UC) management encompasses conventional and advanced treatments, including biological therapy and small molecules. Surgery, particularly in the form of ileal pouch-anal anastomosis (IPAA), is indicated in cases of refractory/severe disease. IPAA can lead to acute complications (e.g., acute pouchitis) as well as late complications, including chronic inflammatory disorders of the pouch. Chronic pouchitis, including the antibiotic-dependent (CADP) and antibiotic-refractory (CARP) forms, represents a significant and current therapeutic challenge due to the substantial need for evidence regarding viable treatment options. Biological therapies have shown promising results, with infliximab, adalimumab, ustekinumab, and vedolizumab demonstrating some efficacy in chronic pouchitis; however, robust randomized clinical trials are only available for vedolizumab. This narrative review focuses on the evidence concerning small molecules in chronic pouchitis, specifically Janus kinase (JAK) inhibitors and sphingosine-1-phosphate receptor (S1P-R) modulators. According to the preliminary studies and reports, Tofacitinib shows a potential effectiveness in CARP. Upadacitinib presents variable outcomes from the case series, necessitating further evaluation. Filgotinib and ozanimod demonstrate anecdotal efficacy. This review underscores the need for high-quality studies and real-world registries to develop robust guidelines for advanced therapies in post-IPAA inflammatory disorders, supported by vigilant clinical monitoring and ongoing education from international IBD specialist societies.

Pelvic Radiation Therapy Increases Risk of Pouch Failure in Patients with Inflammatory Bowel Disease and Ileal Pouch.

BACKGROUND: The effect of radiation on the ileal pouch is less well studied in patients with inflammatory bowel disease (IBD) and ileal pouch-anal anastomosis. AIMS: This retrospective study investigates the impact of external radiation therapy on the outcomes of ileal pouches. METHODS: The study included 82 patients with IBD and ileal pouches, of whom 12 received pelvic radiation, 16 abdominal radiation, 14 radiation in other fields, and 40 served as controls with no radiation. Pouch-related outcomes, including pouch failure, worsening of symptoms, pouchitis, and development of strictures, along with changes in Pouch Disease Activity Index (PDAI) scores pre- and post-radiation were assessed. RESULTS: The pelvic radiation group exhibited a significantly higher rate of pouch failure (25%, p < 0.004) and worsening pouch-related symptoms (75%, p = 0.012) compared to other groups. Although not statistically significant, a higher incidence of pouchitis was observed in the pelvic radiation group (45.5%, p = 0.071). Strictures were more common in the pelvic radiation group (25%, p = 0.043). Logistic regression analysis revealed that pelvic radiation significantly increased the odds of pouch-related adverse outcomes (OR 5.66; 95% confidence interval: 1.61-21.5). CONCLUSION: Pelvic radiation significantly impacts the outcomes of ileal pouches in patients with IBD, increasing the risk of pouch failure, symptom exacerbation, and structural complications. These findings underscore the need for careful consideration of radiation therapy in this patient population and highlight the importance of closely monitoring and managing radiation-induced pouch dysfunction.

Key Focus Areas in Pouchitis Therapeutic Status: A Narrative Review.

Pouchitis, as the most common complication after ileal pouch-anal anastomosis (IPAA), has an incidence from 7% to 46%. Pouchitis treatment still represents one of the biggest gaps of knowledge in the treatment of diseases. This review has focused on achievements and challenges in the treatment of pouchitis. A combined assessment of symptoms, endoscopic findings, histologic results, quick biomarkers, and fecal calprotectin test were determined to be valuable diagnostic criteria. Conventional therapy was described as a modification of bacterial flora, mainly with antibiotics and more recently with probiotics such as bifidobacteria, lactobacilli, and streptococci. Other therapeutic approaches such as anti-tumor necrosis factor, infliximab, adalimumab, vedolizumab, ustekinumab, tacrolimus, tofacitinib, thiopurines, corticosteroids, prolyl hydroxylase-containing enzymes, povidone-iodine, dextrose spray, fecal microbiota transplantation, herbal medicines, and leukocyte apheresis have been discussed. Changes in dietary components, and administration of complementary and alternative medicine, probiotics, and fecal transplantation in addition to conventional therapies were also shown to affect the outcome of disease. Due to the potential significant impairment in quality of life caused by pouchitis, it is essential to address the gaps in knowledge for both patients and physicians in its treatment. Therefore, well-designed and adequately powered studies should assess the optimal treatment for pouchitis.

Acute Pouchitis is Common in Pregnant and Postpartum Women.

INTRODUCTION: The impact of pregnancy on the development of pouchitis in women who have undergone total proctocolectomy with ileal pouch anal anastomosis for ulcerative colitis is poorly understood. METHODS: This was a retrospective study of women with ulcerative colitis who underwent total proctocolectomy with ileal pouch anal anastomosis and subsequently became pregnant at Mount Sinai Hospital. The primary outcome was acute pouchitis during pregnancy or the postpartum period defined as symptoms of increased stool frequency and urgency treated with antibiotics. RESULTS: A total of 44 women with 63 pregnancies and complete data were identified. Acute pouchitis occurred in 14 pregnancies (22.2%) in 12 women and in the postpartum period of 10 pregnancies (15.9%) in 9 women. Acute pouchitis occurred more frequently in women with a history of acute pouchitis immediately before, during, or after pregnancy. DISCUSSION: Acute pouchitis was common during pregnancy and the postpartum period, likely due to microbial shifts. Although not statistically significant, these results provide insight into the impact of pregnancy on the risk of pouchitis and establish the framework for preconception counseling that focuses on prevention and management of pouchitis during pregnancy.

A Rat Model of Pouchitis Following Proctocolectomy and Ileal Pouch-Anal Anastomosis Using Dextran Sulfate Sodium.

Ulcerative colitis (UC) is a chronic immune-mediated disease that affects the entire colon and rectum with a relapsing and remitting course, causing lifelong morbidity. When medical treatment is ineffective, especially in cases of massive gastrointestinal bleeding, perforation, toxic megacolon, or carcinogenesis, surgery becomes the last line of defense to cure UC. Total colorectal resection and ileal pouch-anal anastomosis (IPAA) offer the best chance for long-term treatment. Pouchitis is the most common and troublesome postoperative complication. In this investigation, microsurgery is employed to create an ileal pouch model in experimental rats via IPAA surgery. Subsequently, a sustained rat model of pouchitis is established by inducing inflammation of the ileal pouch with dextran sulfate sodium (DSS). The successful establishment of rat pouchitis is validated through analysis of postoperative general status, weight, food and water intake, fecal data, as well as pouch tissue pathology, immunohistochemistry, and inflammatory factor analysis. This experimental animal model of pouchitis provides a foundation for studying the pathogenesis and treatment of the condition.

The Natural History After Ileal Pouch-Anal Anastomosis for Ulcerative Colitis: A Population-Based Cohort Study From the United States.

INTRODUCTION: There are limited data regarding the natural history after ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC). The principal objectives of this study were to identify 4 key outcomes in the natural history after IPAA within 1, 3, 5, and 10 years: the incidence of pouchitis, Crohn's-like disease of the pouch, use of advanced therapies after IPAA, and pouch failure requiring excision in a network of electronic health records. METHODS: We performed a retrospective cohort study in TriNetX, a research network of electronic health records. In addition to evaluating incidence rates, we also sought to identify factors associated with pouchitis and advanced therapy use within 5 years of IPAA after 1:1 propensity score matching, expressed as adjusted hazard ratios (aHRs). RESULTS: Among 1,331 patients who underwent colectomy with IPAA for UC, the incidence of pouchitis increased from 58% in the first year after IPAA to 72% at 10 years after IPAA. After propensity score matching, nicotine dependence (aHR 1.61, 95% confidence interval [CI] 1.19-2.18), antitumor necrosis factor therapy (aHR 1.33, 95% CI 1.13-1.56), and vedolizumab prior to colectomy (aHR 1.44, 95% CI 1.06-1.96) were associated with an increased risk of pouchitis in the first 5 years after IPAA. The incidence of Crohn's-like disease of the pouch increased to 10.3% within 10 years of IPAA while pouch failure increased to 4.1%. The incidence of advanced therapy use peaked at 14.4% at 10 years after IPAA. DISCUSSION: The incidence of inflammatory conditions of the pouch remains high in the current era, with 14% of patients requiring advanced therapies after IPAA.

Diagnosis and Medical Treatment of Acute and Chronic Idiopathic Pouchitis in Inflammatory Bowel Disease.

Despite the decreased rates in inflammatory bowel disease (IBD) colectomies due to high advances in therapeutic options, a significant number of patients still require proctocolectomy with ileal pouch-anal anastomosis (IPPA) for ulcerative colitis (UC). Pouchitis is the most common complication in these patients, where up to 60% develop one episode of pouchitis in the first two years after UC surgery with IPAA with severe negative impact on their quality of life. Acute cases usually respond well to antibiotics, but 15% of patients will still develop a refractory disease that requires the initiation of advanced immunosuppressive therapies. For chronic idiopathic pouchitis, current recommendations suggest using the same therapeutic options as for IBD in terms of biologics and small molecules. However, the available data are limited regarding the effectiveness of different biologics or small molecules for the management of this condition, and all evidences arise from case series and small studies. Vedolizumab is the only biologic agent that has received approval for the treatment of adult patients with moderately to severely active chronic refractory pouchitis. Despite the fact that IBD treatment is rapidly evolving with the development of novel molecules, the presence of pouchitis represents an exclusion criterion in these trials. Recommendations for the approach of these conditions range from low to very low certainty of evidence, resulting from small randomized controlled trials and case series studies. The current review focuses on the therapeutic management of idiopathic pouchitis.

The Pouch Corner: A Review of Functional Pouch Disorders.

Functional pouch disorders such as dyssynergic defecation, fecal incontinence, and irritable pouch syndrome are common and manifest with symptoms that overlap with those of pouchitis. The appropriate recognition of these disorders is imperative to guide necessary management and reduce unnecessary antibiotic exposure.

[Pouchitis showed complete response to ustekinumab].

Pouchitis is the most common long-term complication following ileal pouch-anal anastomosis (IPAA) in patients with ulcerative colitis. Although several agents, including probiotics, steroids, and immunomodulators, have been used, the treatment of pouchitis remains challenging. Owing to the proven efficacy of biological therapy in inflammatory bowel disease, there is now growing evidence suggesting the potential benefits of biological therapy in refractory pouchitis. Here, we report the case of a 64-year-old woman with pouchitis due to ulcerative colitis who was successfully treated with ustekinumab (UST). The patient developed ulcerative pancolitis at the age of 35. Total colectomy and IPAA with J-pouch anastomosis were performed when the patient was 47 years old. Ileotomy closure was performed 6 months later. Postoperatively, the patient developed steroid-dependent pouchitis. Three years later, she developed steroid-induced diabetes. The patient has been taking 3mg of steroid for 20 years;therefore, her lifetime total steroid dose was 21g. The patient had over 20 episodes of bloody diarrhea a day. The last pouchoscopy in 20XX-9 revealed inflammatory stenosis with deep ulcerations of the afferent limb just before the ileoanal pouch junction. In July 20XX, when we took over her treatment, the policy of treatment was to withdraw her from steroids. Pouchoscopy revealed a widened but still tight afferent limb through which the scope could easily pass, and the ileoanal pouch still showed erosive ileitis without ulcers. Thiopurine administration and steroid tapering were initiated. Steroid tapering increased the erythrocyte sedimentation rate (ESR). As ESR increased, her arthritis exacerbated. Six months after the end of steroid administration, the patient consented to UST treatment. On April 20XX+1, the patient received her first 260-mg UST infusion. At this point, she experienced 14-15 episodes of muddy bloody stools. She had no abdominal pain;however, she experienced shoulder pain. Gradually, UST affected both pouchitis and arthritis. UST treatment was continued at 90mg subcutaneously every 12 weeks without abdominal pain recurrence. Eight months after the first UST infusion, nonsteroidal anti-inflammatory drugs were no longer necessary for shoulder pain. Follow-up pouchoscopy performed 14 months after UST optimization revealed a normal afferent limb without ulcerations in either segment. Pouchitis remission was maintained for over 2 years.

Pouchitis: pathophysiology and management.

Pouchitis is an acute or chronic inflammatory disease of the ileal reservoir. It is common after restorative proctocolectomy with ileal pouch-anal anastomosis, and treatment of chronic antibiotic-refractory pouchitis has proven challenging. Most cases of acute pouchitis evolve into chronic pouchitis. The aetiology of acute pouchitis is likely to be partly related to the gut microbiota, whereas the pathophysiology of chronic pouchitis involves abnormal interactions between genetic disposition, faecal stasis, the gut microbiota, dysregulated host immunity, surgical techniques, ischaemia and mesentery-related factors. Pouchoscopy with biopsy is the most valuable modality for diagnosis, disease monitoring, assessment of treatment response, dysplasia surveillance and delivery of endoscopic therapy. Triggering or risk factors, such as Clostridioides difficile infection and use of non-steroidal anti-inflammatory drugs, should be modified or eradicated. In terms of treatment, acute pouchitis usually responds to oral antibiotics, whereas chronic antibiotic-refractory pouchitis often requires induction and maintenance therapy with integrin, interleukin or tumour necrosis factor inhibitors. Chronic pouchitis with ischaemic features, fistulae or abscesses can be treated with hyperbaric oxygen therapy.

Ouch, my pouch! a clinician's guide to pouchitis.

Pouchitis is defined as inflammation of the ileal pouch created during a restorative proctocolectomy with ileal pouch-anal anastomosis. Although the incidence of this inflammatory condition is high, the exact etiology often remains unclear and the management challenging. In this review, we summarize the clinical presentation, pathogenesis, diagnosis, and management of this common complication.

Radiographic Evaluation of Ileal Pouch Disorders: A Systematic Review.

BACKGROUND: Radiographic imaging of the abdomen and pelvis plays an important role in the diagnosis and management of ileal pouch disorders with modalities including CT, MRI, contrasted pouchography, and defecography. OBJECTIVES: To perform a systematic review of the literature and describe applications of cross-sectional imaging, pouchography, defecography, and ultrasonography. DATA SOURCES: PubMed, Google Scholar, and Cochrane database. STUDY SELECTION: Relevant articles on endoscopy in ileal pouches published between January 2003 and June 2023 in English were included on the basis of Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. INTERVENTION: Main abdominal and pelvic imaging modalities and their applications in the diagnosis of ileal pouch disorders were included. MAIN OUTCOME MEASURES: Accuracy in characterization of ileal pouch disorders. RESULTS: CT is the test of choice for the evaluation of acute anastomotic leaks, perforation, and abscess(es). MRI of the pelvis is suitable for the assessment of chronic anastomotic leaks and their associated fistulas and sinus tracts, as well as for the penetrating phenotype of Crohn's disease of the pouch. CT enterography and magnetic resonance enterography are useful in assessing intraluminal, intramural, and extraluminal disease processes of the pouch and prepouch ileum. Water-soluble contrast pouchography is particularly useful for evaluating acute or chronic anastomotic leaks and outlines the shape and configuration of the pouch. Defecography is the key modality to evaluate structural and functional pouch inlet and outlet obstructions. Ultrasonography can be performed to assess the pouch in experienced IBD centers. LIMITATIONS: This is a qualitative, not quantitative, review of mainly case series and case reports. CONCLUSIONS: Abdominopelvic imaging, along with clinical and endoscopic evaluation, is imperative for accurately assessing structural, inflammatory, functional, and neoplastic disorders. See video from symposium .

Diagnosis and Treatment of Pouch Disorders in Children: A Systematic Review.

BACKGROUND: Restorative proctocolectomy and IPAA have become the surgical procedure of choice in pediatric patients with medically refractory colitis or familial adenomatous polyposis. OBJECTIVE: This systematic review aims to assess the diagnosis and treatment of pouch disorders in pediatric patients who undergo IPAA. DATA SOURCES: A literature search was performed using MEDLINE, Google Scholar, and Embase for all publications describing outcomes of pediatric IPAA. STUDY SELECTION: Studies between January 1, 2000, and September 7, 2022, published in English were included. Studies were excluded on the basis of title, abstract, and full-length review. INTERVENTIONS: IPAA. MAIN OUTCOME MEASURES: Pouch disorders described include anastomotic leaks, pouch strictures, pouch failure, pouchitis, cuffitis, and de novo Crohn's disease of the pouch. RESULTS: Thirty-three studies were included in this review, all of which were retrospective in nature. The outcomes of 2643 pediatric patients were included in the 33 studies. LIMITATIONS: Management is largely informed by clinical practices in adult patients with scant data on treatment efficacy in children. CONCLUSIONS: The reported incidence of disorders of the pouch in children varies widely and is likely attributable to differences in definitions and follow-up periods across studies. Pouchitis was the most frequently described outcome. The overall rate of pouch failure in children is relatively low, with de novo Crohn's disease of the pouch being the most significant risk factor. Multicenter prospective studies are needed in the pediatric population to accurately identify risk factors, standardize the assessment of pouch complications, and determine effective treatment strategies. See video from the symposium .

Management of Primary Sclerosing Cholangitis and Extraintestinal Disorders in Patients With Ileal Pouches: A Systematic Review.

BACKGROUND: Restorative proctocolectomy with IPAA improves the quality of life in patients with ulcerative colitis by the removal of diseased large bowel and preservation of the natural route of defecation. Although the surgery may improve preexisting extraintestinal manifestations in the joints, skin, and eyes, extraintestinal manifestations, particularly primary sclerosing cholangitis, can persist after colectomy. OBJECTIVES: A systematic review of diagnosis and treatment of liver, joint, skin, and eye manifestations in patients with restorative proctocolectomy and IPAA for ulcerative colitis. DATA SOURCES: PubMed, Google Scholar, and Cochrane database. STUDY SELECTION: Relevant articles on primary sclerosing cholangitis and extraintestinal manifestations in ileal pouches published between January 2001 and July 2023 in English were included on the basis of Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. INTERVENTION: Diagnosis and treatment of primary sclerosing cholangitis and extraintestinal manifestations in patients with restorative proctocolectomy and IPAA were included. MAIN OUTCOME MEASURES: Association between primary sclerosing cholangitis, extraintestinal manifestations, and inflammatory disorders of the pouch and their management. RESULTS: Primary sclerosing cholangitis and extraintestinal manifestations are associated with pouchitis, particularly chronic pouchitis. Primary sclerosing cholangitis is associated with chronic pouchitis, enteritis, and possible pouch neoplasia. However, the disease severity and course of primary sclerosing cholangitis and pouchitis do not appear to be parallel. Despite the fact that oral vancomycin or budesonide have been used to treat primary sclerosing cholangitis-associated pouchitis, their impact on the disease course of primary sclerosing cholangitis is not known. Biological therapy for chronic inflammatory disorders of the pouch may also be beneficial for the concurrent extraintestinal manifestations of the joints, skin, and eyes. However, studies on the correlation between the severity of inflammatory pouch disorders and the severity of joint, skin, and eye diseases are lacking. LIMITATIONS: This is a qualitative, not quantitative, review of case series and case reports. CONCLUSIONS: Primary sclerosing cholangitis and extraintestinal manifestations of the joints, skin, and eyes appear to be associated with inflammatory disorders of the ileal pouch. Although the treatment of pouchitis does not seem to affect the disease course of primary sclerosing cholangitis, effective therapy of inflammatory pouch disorders, particularly with biologics, likely benefits concurrent disorders of the joints, skin, and eyes. See video from the symposium .

Histopathological Evaluation of Pouch Neoplasia in IBD and Familial Adenomatous Polyposis.

BACKGROUND: IPAA is often required for patients with ulcerative colitis or familial adenomatous polyposis after colectomy. This procedure reduces but does not completely eliminate the risk of neoplasia. OBJECTIVE: This study focuses on the histopathology of neoplasia in the ileal pouch, rectal cuff, and anal transition zone. DATA SOURCES: We performed a MEDLINE search for English-language studies published between 1981 and 2022 using the PubMed search engine. The terms "ileal pouch-anal anastomosis," "pouchitis," "pouch dysplasia," "pouch lymphoma," "pouch squamous cell carcinoma," "pouch adenocarcinoma," "pouch neoplasia," "dysplasia of rectal cuff," and "colitis-associated dysplasia" were used. STUDY SELECTION: Human studies of neoplasia occurring in the pouch and para-pouch were selected, and the full text was reviewed. Comparisons were made within and across studies, with key concepts selected for inclusion in this article. CONCLUSIONS: Neoplasia in the pouch is a rare complication in patients with IPAA. Annual endoscopic surveillance is recommended for familial adenomatous polyposis patients and ulcerative colitis patients with a history of prior dysplasia or carcinoma. In familial adenomatous polyposis, dysplastic polyps of the pouch are visible and readily amenable to endoscopic removal; however, glandular dysplasia in the setting of ulcerative colitis may be invisible on endoscopy. Therefore, random biopsies and adequate tissue sampling of the pouch and rectal cuff are recommended in this setting. The histological diagnosis of IBD-associated dysplasia can be challenging and should be confirmed by at least 1 expert GI pathologist. See video from the symposium.

Normal Ileal Mucus Is Inadequate for Epithelial Protection in Ileal Pouch Mucosa.

BACKGROUND: Clinical, nonspecific pouchitis is common after restorative proctocolectomy for ulcerative colitis, but its cause is unknown. A possible lack of protection for the ileal mucosa in its role as a reservoir for colonic-type bacteria may be the missing piece in defining the causes of pouchitis. OBJECTIVE: The study aimed to review the causes of pouchitis and introduce the hypothesis that inadequate mucus protection in the pouch, combined with a predisposition to abnormal inflammation, is the most common cause of nonspecific pouchitis. DATA SOURCES: Review of PubMed and MEDLINE for articles discussing pouchitis and intestinal mucus. STUDY SELECTION: Studies published from 1960 to 2023. The main search terms were "pouchitis," and "intestinal mucus," whereas Boolean operators were used with multiple other terms to refine the search. Duplicates and case reports were excluded. MAIN OUTCOME MEASURES: Current theories about the cause of pouchitis, descriptions of the role of mucus in the physiology of intestinal protection, and evidence of the effects of lack of mucus on mucosal inflammation. RESULTS: The crossreference of "intestinal mucus" with "pouchitis" produced 9 references, none of which discussed the role of mucus in the development of pouchitis. Crossing "intestinal mucus" with "pouch" resulted in 32 articles, combining "pouchitis" with "barrier function" yielded 37 articles, and "pouchitis" with "permeability" yielded only 8 articles. No article discussed the mucus coat as a barrier to bacterial invasion of the epithelium or mentioned inadequate mucus as a factor in pouchitis. However, an ileal pouch produces a colonic environment in the small bowel, and the ileum lacks the mucus protection needed for this sort of environment. This predisposes pouch mucosa to bacterial invasion and chronic microscopic inflammation that may promote clinical pouchitis in patients prone to an autoimmune response. LIMITATIONS: No prior studies address inadequate mucus protection and the origin of proctitis. There is no objective way of measuring the autoimmune tendency in patients with ulcerative colitis. CONCLUSIONS: Studies of intestinal mucus in the ileal pouch and its association with pouchitis are warranted.

Endoscopic Evaluation of the Ileal Pouch.

BACKGROUND: Structural and inflammatory adverse sequelae are common after restorative proctocolectomy and IPAA. On rare occasions, neoplasia can occur in patients with ileal pouches. Pouchoscopy plays a key role in the diagnosis, differential diagnosis, disease monitoring, assessment of treatment response, surveillance, and delivery of therapy. OBJECTIVE: A systematic review of the literature was performed, and principles and techniques of pouchoscopy were described. DATA SOURCES: PubMed, Google Scholar, and Cochrane databases. STUDY SELECTION: Relevant articles on endoscopy in ileal pouches published between January 2000 and May 2023 were included based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. INTERVENTION: Diagnostic, surveillance, and therapeutic endoscopy in ileal pouch disorders were included. MAIN OUTCOME MEASURES: Accurate characterization of the ileal pouch in healthy or diseased states. RESULTS: The main anatomic structures of a J- or S-pouch are the stoma closure site, prepouch ileum, inlet, tip of the "J," pouch body, anastomosis, cuff, and anal transition zone. Each anatomic location can be prone to the development of structural, inflammatory, or neoplastic disorders. For example, ulcers and strictures are common at the stoma closure site, inlet, and anastomosis. Leaks are commonly detected at the tip of the "J" and anastomosis. Characterization of the anastomotic distribution of inflammation is critical for the differential diagnosis of subtypes of pouchitis and other inflammatory disorders of the pouch. Neoplastic lesions, albeit rare, mainly occur at the cuff, anal transition zone, or anastomosis. LIMITATIONS: This is a qualitative, not quantitative, review of mainly case series. CONCLUSIONS: Most structural, inflammatory, and neoplastic disorders can be reliably diagnosed with a careful pouchoscopy. The endoscopist and other clinicians taking care of pouch patients should be familiar with the anatomy of the ileal pouch and be able to recognize common abnormalities. See video from symposium.

Faecal Microbiota Transplantation [FMT] in the Treatment of Chronic Refractory Pouchitis: A Systematic Review and Meta-analysis.

BACKGROUND: The aim of this systematic review and meta-analysis is to assess the efficacy and safety of faecal microbiota transplantation [FMT] in the treatment of chronic pouchitis. METHODS: A PRISMA-compliant systematic review and meta-analysis was conducted using the following databases and clinical trial registers: Medline, Embase, Scopus, Cochrane Database of Systematic Reviews [CENTRAL], clinical trials.gov, ScienceDirect, and VHL [virtual health library]. The primary outcome was clinical response/remission in patients treated with FMT. Secondary outcomes included safety profile, quality of life, and changes in the gut microbiome. RESULTS: Seven observational cohort studies/case series and two randomised, controlled trials with a total of 103 patients were included. The route, preparation, and quantity of FMT administered varied among the included studies. Clinical response rate of 42.6% with a remission rate of 29.8% was estimated in our cohort following FMT therapy. Minor, self-limiting, adverse events were reported, and the treatment was well tolerated with good short- and long-term safety profiles. Successful FMT engraftment in recipients varied and, on average, microbial richness and diversity was lower in patients with pouchitis. In some instances, shifts with specific changes towards abundance of species, suggestive of a 'healthier' pouch microbiota, were observed following treatment with FMT. CONCLUSION: The evidence for FMT in the treatment of chronic pouchitis is sparse, which limits any recommendations being made for its use in clinical practice. Current evidence from low-quality studies suggests a variable clinical response and remission rate, but the treatment is well tolerated, with a good safety profile. This review emphasises the need for rationally designed, well-powered, randomised, placebo-controlled trials to understand the efficacy of FMT for the treatment of pouchitis.