Ileal Pouch-anal Anastomosis Research Articles

Long-term Prognostic Impact of Metachronous Rectal Cancer in Patients With Familial Adenomatous Polyposis: A Single-center Retrospective Study.

To evaluate the risk factors and long-term prognosis of metachronous rectal cancer in the remnant rectum of patients with familial adenomatous polyposis (FAP). Sixty-five patients (49 families) who underwent prophylactic surgery, including bowel resection, for FAP between January 1976 and August 2022 at Hamamatsu University Hospital were included and divided into two groups based on the presence of metachronous rectal cancer. Risk factors for metachronous rectal cancer development were analysed in cases treated with total colectomy with ileorectal anastomosis (IRA) and stapled total proctocolectomy with ileal pouch anal anastomosis (IPAA) (IRA, n=22; stapled IPAA n=20; total, n=42). The median surveillance period was 169 months. Twelve patients developed metachronous rectal cancer (IRA, n=5; stapled IPAA, n=7), of which six with advanced cancer died. Patients who temporarily dropped out of surveillance were significantly more likely to have metachronous rectal cancer (metachronous vs. non-metachronous rectal cancer: 33.3% vs. 1.9%, p<0.01). The mean duration of surveillance suspension was 87.8 months. Cox regression analysis revealed that temporary surveillance drop-out independently affected the risk (p=0.04). The overall survival associated with metachronous rectal cancer was 83.3% at 1 year and 41.7% at 5 years. Overall survival was significantly worse in advanced cancer than in early cancer cases (p<0.01). Temporary drop-out from surveillance was a risk factor for metachronous rectal cancer development, and advanced cancer had a poor prognosis. Continuous surveillance of patients with FAP, without temporary drop-out, is strongly recommended.

Risk factors and outcomes of restorative proctocolectomy with ileal pouch-anal anastomosis for ulcerative colitis. Retrospective study of 75 single center cases.

Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the surgical gold standard in patients with ulcerative colitis (UC). Results are generally satisfactory but there is a significant rate of patients who experience postoperative complications. The aims of our study were to identify the pre- and intraoperative risk factors and their correlation with the reported outcomes. A retrospective study was conducted on the medical records of all consecutive patients undergoing restorative proctocolectomy with IPAA for UC in our center from 2010 to 2021. Pre- and intraoperative factors were examined and correlated with pouchitis, endoscopic pouchitis, pouch failure, anastomotic leak, postoperative complications classified according to Clavien-Dindo score and stoma outlet obstruction. A univariate and multivariate statistical analysis was performed. Out of 75 patients undergoing 3- or 2-stage IPAA surgery, the coexistence of extraintestinal clinical manifestations and preoperative topical rectal stump therapy for active proctitis were significantly associated with the occurrence of pouchitis (OR=4.4, p=0.03 and OR=7.6, p=0.01). Endoscopic pouchitis was found to be related to preoperative topical rectal therapy (OR=10.2, p=0.007), but not to extraintestinal manifestations of disease. Anastomotic leak was found to be significantly related to pouch failure (OR=22.7, p=0.007). Surgical indication for malignancy increased the risk for early complications (Clavien-Dindo >2) (OR=16.0, p=0.04). Young age was associated with the occurrence of outlet stoma obstruction in patients with recent IPAA surgery (OR=0.97, p=0.05). Based on observed results, an appropriate preoperative patient assessment aimed at detecting specific risk factors is crucial to identify early or prevent worse outcomes in patients undergoing IPAA surgery.

Ileoanal pouch-related fistulae: A systematic review with meta-analysis on incidence, treatment options and outcomes.

Ileoanal pouch related fistulae (PRF) are a complication of restorative proctocolectomy often requiring repeated surgical interventions and with a high risk of long-term recurrence and pouch failure. To assess the incidence of PRF and to report on the outcomes of available surgical treatments. A PRISMA-compliant systematic literature search for articles reporting on PRF in patients with inflammatory bowel diseases (IBD) or familial adenomatous polyposis (FAP) from 1985 to 2020. 34 studies comprising 770 patients with PRF after ileal-pouch anal anastomosis (IPAA) were included. Incidence of PRF was 1.5-12%. In IBD patients Crohn's Disease (CD) was responsible for one every four pouch-vaginal fistulae (PVF) (OR 24.7; p=0.001). The overall fistula recurrence was 49.4%; procedure-specific recurrence was: repeat IPAA (OR 42.1; GRADE +); transvaginal repair (OR 52.3; GRADE ++) and transanal ileal pouch advancement flap (OR 56.9; GRADE ++). The overall failure rate was 19%: pouch excision (OR 0.20; GRADE ++); persistence of diverting stoma (OR 0.13; GRADE +) and persistent fistula (OR 0.18; GRADE +). PVFs are more frequent compared to other types of PRF and are often associated to CD; surgical treatment has a risk of 50% recurrence. Repeat IPAA is the best surgical approach with a 42.1% recurrence rate.

The anatomy and physiology of the ileal pouch and its relevance to pouch dysfunction.

For the last 40years, the ileal pouch-anal anastomosis has been used in patients with ulcerative colitis, familial adenomatous polyposis, and occasionally severe constipation to reconstruct the gastrointestinal tract after proctocolectomy. Although the procedure has generally been successful in helping patients avoid an ileostomy, it has come with its own set of problems. These include complications of the surgery such as fistulas and bowel obstruction, persistent inflammation of the pouch known as pouchitis, and functional problems related to the lack of expulsive peristalsis in the pouch. It is this last group of problems that is exacerbated by a poor diet, ill-advised anti-diarrheal medications, anal stenosis and pouch twists. As a consequence, patients with pouch problems are frequently referred for radiologic evaluation, with pouchography, defecation studies, and small bowel imaging commonly requested. In this review, the basic anatomy and physiology of the ileal pouch are discussed to provide a logical baseline against which to measure the anatomy of pouches and its relationship to the symptoms of pouch dysfunction.

Hepatobiliary manifestations following two-stages elective laparoscopic restorative proctocolectomy for patients with ulcerative colitis: A prospective observational study.

Hepatobiliary manifestations occur in ulcerative colitis (UC) patients. The effect of laparoscopic restorative proctocolectomy (LRP) with ileal pouch anal anastomosis (IPAA) on hepatobiliary manifestations is debated. To evaluate hepatobiliary changes after two-stages elective laparoscopic restorative proctocolectomy for patients with UC. Between June 2013 and June 2018, 167 patients with hepatobiliary symptoms underwent two-stage elective LRP for UC in a prospective observational study. Patients with UC and having at least one hepatobiliary manifestation who underwent LRP with IPAA were included in the study. The patients were followed up for four years to assess the outcomes of hepatobiliary manifestations. The patients' mean age was 36 ± 8 years, and males predominated (67.1%). The most common hepatobiliary diagnostic method was liver biopsy (85.6%), followed by Magnetic resonance cholangiopancreatography (63.5%), Antineutrophil cytoplasmic antibodies (62.5%), abdominal ultrasonography (35.9%), and Endoscopic retrograde cholangiopancreatography (6%). The most common hepatobiliary symptom was Primary sclerosing cholangitis (PSC) (62.3%), followed by fatty liver (16.8%) and gallbladder stone (10.2%). 66.4% of patients showed a stable course after surgery. Progressive or regressive courses occurred in 16.8% of each. Mortality was 6%, and recurrence or progression of symptoms required surgery for 15%. Most PSC patients (87.5%) had a stable course, and only 12.5% became worse. Two-thirds (64.3%) of fatty liver patients showed a regressive course, while one-third (35.7%) showed a stable course. Survival rates were 98.8%, 97%, 95.8%, and 94% at 12 mo, 24 mo, 36 mo, and at the end of the follow-up. In patients with UC who had LRP, there is a positive impact on hepatobiliary disease. It caused an improvement in PSC and fatty liver disease. The most prevalent unchanged course was PSC, while the most common improvement was fatty liver disease.

Comparison of The Toronto IBD Global Endoscopic Reporting (TIGER) score, Mayo endoscopic score (MES), and ulcerative colitis endoscopic index of severity (UCEIS) in predicting the need for ileal pouch–anal anastomosis in patients with ulcerative colitis

Total proctocolectomy (TPC) with ileal pouch-anal anastomosis (IPAA) has been accepted as a radical surgery for refractory ulcerative colitis (UC). We aimed to assess the predictive value of several novel and widely used endoscopic core systems, The Toronto IBD Global Endoscopic Reporting (TIGER) score, Mayo endoscopic score (MES), and ulcerative colitis endoscopic index of severity (UCEIS) in guiding the need for IPAA. Data on patients with UC from June 1986 and June 2022 at our institute were collected. The endoscopic evaluation was recorded according to the first colonoscopy after hospitalization. Primary outcome was the need for IPAA during admission and follow-up. A total of 313 patients with a median follow-up time and a median TIGER score of 12.0years (interquartile range (IQR): 6.0-17.0) and 212.0 (IQR: 7.0-327.0) were enrolled. IPAA was conducted in 110 (35.1%) patients, which significantly improved the long-term quality of life. TIGER score had the biggest area under the receiver-operating characteristic curve of 0.810 with a sensitivity of 75.0% and specificity of 87.1% at the cut-off value of 315 (p < 0.001). TIGER score ≥ 315 was an independent risk factor with the highest odds ratio for the need for IPAA and associated with the shortest IPAA-free survival time compared with UCEIS and MES. TIGER score was superior to UCEIS and MES in predicting the need for IPAA. For colorectal surgeons, three or more segments with moderate-to-severe endoscopic activity should be considered as a threshold value for decision-making for IPAA.

Evaluation and management of ileal pouch-anal anastamosis (IPAA) complications in pregnancy, and the impacts of an IPAA on fertility.

Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) remains the preferred surgical option for medically refractory ulcerative colitis. Management of individuals with an IPAA prior to and during pregnancy presents challenges that can have serious consequences. Infertility, mechanical obstructive and inflammatory pouch complications are frequently encountered in pregnant women with an IPAA. Mechanical obstructions occur due to a variety of underlying aetiologies, including stricturing disease, adhesions and pouch twists. Conservative management of such obstructions often results in resolution of symptoms without a need for endoscopic or surgical intervention, although endoscopic decompression may be attempted in isolation or as a bridge to definitive surgical intervention. Parenteral nutrition, and early delivery, may also be necessary. Faecal calprotectin and intestinal ultrasound, both of which are accurate in pregnancy, are useful in the setting of suspected inflammatory pouch complications, in some circumstances allowing for avoidance of pouchoscopy. Penicillin-based antimicrobials can be considered first line in pregnancy for the management of pouchitis and pre-pouch ileitis, and biologics can be safely instituted in the setting of refractory disease or suspected Crohn's disease-like inflammation of the pouch or pre-pouch ileum. Pragmatism, clear patient communication and multidisciplinary discussion are essential in approaching pregnant women with complications of an IPAA, particularly given the lack of definitive evidence to guide therapeutic decisions.

Surgical management of colonic perforation due to ulcerative colitis: report of a case

Surgical treatment of ulcerative colitis (UC) is indicated electively in failure of medical therapy and development of malignancy and dysplasia in long standing cases and acutely in fulminant colitis, perforation, bleeding, obstruction or in toxic megacolon. The surgical procedure in the past used to be total proctocolectomy with permanent ileostomy with its attendant psychological, social, physical, and sexual problems. With the advent of ileal pouch–anal anastomosis (IPAA) patients with UC can have a good quality of life without fear of having the permanent ileostomy. The advancement of minimally access surgery has added a new wing to the surgical armamentarium in coping the postoperative recovery, body image, sexual dysfunction etc. Laparoscopic surgery appeals to patients undergoing IPAA because they are generally young and hope to gain the potential benefit of reduced disability, more rapid recovery, and a better body image as a result of more cosmetic incisions. Depending upon the clinical presentation patient may require two or three stage procedure.

The Incidence of Pouch Neoplasia Following Ileal Pouch-Anal Anastomosis in Patients With Inflammatory Bowel Disease.

Ileal pouch-anal anastomosis (IPAA) is the standard restorative procedure following proctocolectomy in patients with inflammatory bowel disease (IBD) who require colectomy. However, removal of the diseased colon does not eliminate the risk of pouch neoplasia. We aimed to assess the incidence of pouch neoplasia in IBD patients following IPAA. All patients at a large tertiary center with International Classification of Diseases-Ninth Revision/International Classification of Diseases-Tenth Revision codes for IBD who underwent IPAA and had subsequent pouchoscopy were identified using a clinical notes search from January 1981 to February 2020. Relevant demographic, clinical, endoscopic, and histologic data were abstracted. In total, 1319 patients were included (43.9% women). Most had ulcerative colitis (95.2%). Out of 1319 patients, 10 (0.8%) developed neoplasia following IPAA. Neoplasia of the pouch was seen in 4 cases with neoplasia of the cuff or rectum seen in 5 cases. One patient had neoplasia of the prepouch, pouch, and cuff. Types of neoplasia included low-grade dysplasia (n = 7), high-grade dysplasia (n = 1), colorectal cancer (n = 1), and mucosa-associated lymphoid tissue lymphoma (n = 1). Presence of extensive colitis, primary sclerosing cholangitis, backwash ileitis, and rectal dysplasia at the time of IPAA were significantly associated with increased risk of pouch neoplasia. The incidence of pouch neoplasia in IBD patients who have undergone IPAA is relatively low. Extensive colitis, primary sclerosing cholangitis, and backwash ileitis prior to IPAA and rectal dysplasia at the time of IPAA raise the risk of pouch neoplasia significantly. A limited surveillance program might be appropriate for patients with IPAA even with a history of colorectal neoplasia.

Rectal Cancer and Radiation in Colitis.

Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer. When IBD patients develop a rectal cancer, this should be treated with the same oncological principles and guidelines as the general population. Rectal cancer treatment includes surgery, chemotherapy, and radiation therapy (RT). Many IBD patients will require a total proctocolectomy with an ileal-pouch anal anastomosis (IPAA) and others, restoration of intestinal continuity may not be feasible or advisable. The literature is scarce regarding outcomes of IPAA after RT. In the present review, we will summarize the evidence regarding RT toxicity in IBD patients and review surgical strategies and outcomes of IPAA after RT.

Evaluating the Relationship Between Nutrition and Post-colectomy Pouchitis in Pediatric Patients with Ulcerative Colitis.

Pouchitis is the most frequent complication following restorative proctocolectomy and ileal pouch anal anastomosis (RP-IPAA) in patients with Ulcerative colitis (UC). Pediatric data on nutritional status during RP-IPAA and in patients with pouchitis are limited. We aimed to delineate nutritional changes in children undergoing 2-stage and 3-stage surgeries and to evaluate the association between nutrition and the development of recurrent or chronic pouchitis. This single-center retrospective study involved 46 children with UC who underwent a RP-IPAA. Data were collected at each surgical stage and for up to 2-year post-ileostomy takedown. We used Wilcoxon matched-pairs signed-rank test to evaluate the differences in nutritional markers across surgical stages and logistic regression to identify the factors associated with recurrent or chronic pouchitis. Twenty patients (43.5%) developed recurrent or chronic pouchitis. Children who underwent a 3-stage procedure had improvements in albumin, hematocrit, and body mass index (BMI)-for-age Z-scores (p < 0.01) between the first two stages. A positive trend in BMI-for-age Z-scores (p = 0.08) was identified in children with 2-stage procedures. All patients showed sustained nutritional improvement during the follow-up period. Among patients who underwent 3-stage surgeries, BMI worsened by 0.8 standard deviations (SDs) (p = 0.24) between the initial stages in those who developed recurrent or chronic pouchitis and improved by 1.1 SDs (p = 0.04) in those who did not. Early improvement in BMI-for-age Z-scores following the initial stage was associated with lower rates of recurrent or chronic pouchitis. Larger prospective studies are needed to validate these findings.

Curable leakage in stapled IPAA has little effect on the long-term pouch function.

This study aimed to evaluate the frequency and grade of anastomotic leakage (AL) in stapled ileal pouch-anal anastomosis (IPAA) and its long-term impact on the pouch functions. A longitudinal cohort study was conducted on UC patients who underwent stapled IPAA at Yokohama City University Medical Center between 2007 and 2018. The diagnosis and grading of AL were performed in accordance with the recommendations of the International Study Group of Rectal Cancer. We assessed the functional pouch rate, late complication, pouch survival rate, bowel function (bowel movements per day, soiling, spotting, difficulty in distinguishing feces from flatus) and pouch inflammation (pouchitis disease activity index; PDAI) in the long-term period. Two hundred seventy-six patients were analyzed. Twenty-three (8.3%; grade B/C; 13/10) patients were diagnosed with AL, but a functional pouch was achieved in all the twenty-three patients. Anastomotic stricture was significantly more common in patients with AL (AL group) than in patients without AL (non-AL group; AL/non-AL: 13.0/3.2%, p = 0.020). There were no differences in other late complications. Furthermore, the pouch survival rate did not differ between the AL and non-AL groups (100.0/97.9%/10years, p = 0.494). There were no differences between the groups in bowel movements per day, spotting, soling, difficulty in distinguishing feces from flatus, or PDAI postoperatively. Curable AL may not affect late complications (except anastomotic stricture), pouch survival, the bowel function, or pouch inflammation over the long term. Perioperative management to prevent the severity of AL is as important as preventing its occurrence.

Impact of the body mass index on the retention of the anorectal mucosa after double-stapled ileal pouch-anal anastomosis for ulcerative colitis

BackgroundDouble-stapled ileal pouch-anal anastomosis (DS-IPAA) is easy to construct and has a good functional outcome in patients with ulcerative colitis (UC). However, retention of the anorectal mucosa may lead to a subsequent risk of inflammation and neoplasia. This study aimed to identify factors associated with the retention of a large amount of anorectal mucosa after DS-IPAA.MethodsThe medical records of 163 patients who had undergone one-stage total proctocolectomy and DS-IPAA for UC between 2007 and 2020 were retrospectively reviewed. The patients were divided into two groups according to the length of the retained mucosa. The high anastomosis group was defined as having a retained mucosal length of ≥ 30 mm in the anterior or posterior wall. Clinical factors were compared between the high and low anastomosis groups.ResultsThe high anastomosis group showed a significantly higher body mass index (BMI) (high vs. low: 23.2 vs. 19.0), longer operation time (304 vs. 263) and greater blood loss (357 vs. 240). In the multivariate analysis, high BMI was the only factor significantly associated with high anastomosis (odds ratio 1.32). There was a positive correlation between BMI and the length of the retained mucosa.ConclusionsIn DS-IPAA, BMI showed the strongest association with the retention of a large amount of the anorectal mucosa. In high BMI patients, although the risk of inability of anastomosis is little than that of IPAA with mucosectomy, the possible retention of a large amount of mucosa should be considered.

P449 Minimally invasive IPAA in UC: Preliminary results from a referral center

Abstract Background Minimally invasive approaches in performing restaurative total proctocolectomy in Ulcerative Colitis(UC) have been increasingly adopted. In particular, the robotic approach could be used with more benefits in proctectomy with ileal pouch anal anastomosis (IPAA). In fact, the robotic device seems to potentially overcome all the limitations found in laparoscopic and conventional open surgery. The aim of our study was to compare and evaluate early and late functional postoperative outcomes and complications after IPAA, performed with open, laparoscopic and robotic techniques in UC patients. Methods At our institution, 397 UC patients who underwent restorative proctocolectomy with IPAA during the period 1986-2022, consecutively treated either with open surgery, laparoscopic or robotic techniques were enrolled. The incidence of early (&amp;lt;30 days) and late (&amp;gt;30 days) postoperative complications (intestinal occlusion, haematoma/wound infection, anastomotic dehiscence), hospital stay and an assessment about continence, autonomic nerve damage, incidence of pouchitis and cuffitis was evaluated. Results About the 397 patients, 344 underwent conventional open IPAA, 31 laparoscopically and 22 robotically. Comparable early and late postoperative surgical complications were recorded among the different techniques [early and late complications respectively 24/53 (45,2%) and 146/344(42,4%)] in minimally invasive and open groups. Minimally invasive surgery showed a better outcome regarding wound infections [0/53 (0%)], anastomotic dehiscence and reduced length of stay but open surgery demonstrated a better result on early and late intestinal occlusion [8/53 (15%)vs 22/344 (6,39%)] and anastomotic stenosis [5/53 (9,43%) vs 15/344 (4,36%)]. Lastly, the rate of cuffitis was higher in open surgery than in the minimally invasive group [(3/53 (5,66%) vs 46/344(13,37%)] and within these, robotic approach seems to show better results compared to laparoscopy. Conclusion UC patients undergoing IPAA could benefit from a minimally invasive surgical approach. Our experience confirms that robotics seems to be related to hopeful outcomes both in the short and long term period, even if more studies are needed to refine the promising results.

P281 Conversion of the ileal pouch-anal anastomosis to a continent ileostomy – outcome and patient satisfaction

Abstract Background This is a description of consecutive patients converted from ileal pouch-anal anastomosis (IPAA) to continent ileostomy (CI) at a tertiary centre, outcome after surgery and patient satisfaction after long time follow-up. Methods All consecutive patients operated with IPAA which later was converted to a CI at Sahlgrenska University Hospital, Gothenburg, Sweden, were included in the study. Demographic data was registered and a questionnaire regarding quality of life was sent to included patients. Results A total of 28 patients were included during the period of 1985-2022. The most common diagnosis was Ulcerative Colitis (UC) (n=23), other diagnoses included Crohn′s disease (n=2) and Familial Adenomatous Polyposis (n=1) (missing data n=2). IPAA was performed at a mean age of 30 (15-49) years and IPAA converted to CI at a mean age of 39 (22-62) years. At follow-up, three of the patients were diseased, not related to conversion surgery, and one had moved abroad. All of the remaining 24 patients completed the questionnaire. 20/28 (71%) patients still had their CI in function. 17/28 (61%) were converted due to fistula problems and the rest due to functional problems. 20/28 (71%) were converted using their IPAA-pouch and 4/28 (14%) had a new-constructed reservoir (missing data n=4). Totally, 18/20 (90% p&amp;lt;0.001) were satisfied with the CI and 19/20 (95% p&amp;lt;0.001) would choose it again if they were facing the same situation, even if most of the patients needed revision of the reservoir (mean 2 (0-5) surgeries). Four patients required excision of the CI. All excised patients had UC and was converted using their original IPAA. The main reason for conversion in the excised group was fistula with the inner meatus in the IPAA (three woman with anovaginal fistula and one man with perianal fistula). Conclusion A CI is an alternative that patients seem to be satisfied with, even after long follow-up time, when IPAA is no longer a suitable alternative. The majority of the patients in this study were converted from IPAA to CI using their IPAA-pouch.

P910 Emerging role of IL-33/ST2 and Gut Microbiota axis in the inflammatory process of ulcerative colitis patients with ileal pouch-anal anastomosis

Abstract Background IL-33/ST2 axis and gut microbiota are important factors in the pathogenesis of IBD with a potential reciprocal influence. IL-33/ST2 axis controls the mucosal healing process during intestinal inflammation. Pouchitis, after restorative proctocolectomy with ileal pouch-anal anastomosis, is the most common complication. We aimed to explore the potential correlation between mucosal cytokines and gut microbiota in the inflammatory process of pouchitis. Methods 23 patients with ileal pouch-anal anastomosis were enrolled. 13 showed pouchitis and 10 a normal pouch. Mucosal samples were collected from the afferent ileal loop and from the pouch. Multiplex analysis for cytokines was performed. ELISA, western blot and IHC were run to assess IL-33/ST2 axis. Microbiota was analyzed by 16S ribosomal RNA gene amplicon pyrosequencing. Pouchitis Disease Activity Index and Pouchitis Histological Score were calculated. Multivariate analyses were run to generate transcriptional interaction networks and identify biomarkers for patients with inflamed pouches. Results IL-1Ra, IL-6, IL-8, IL-17, IP-10, MCP-1, MIP-1a, MIP-1b were increased in the inflamed pouch vs. normal pouch. No differences were registered in samples from the afferent ileal loop. In pouchitis, IL-7 resulted reduced in the inflamed pouch vs. the ileal loop. In normal pouch, no differences were recorded. In pouchitis, IL-33 and ST2 protein levels were significantly reduced in the pouch vs. the ileal loop and resulted decreased vs. normal pouch. Full-length, bioactive IL33, ST2L and sST2 were expressed in all experimental groups; the cleaved, less active form of IL33 was increased only in pouchitis. IL-33 and ST2 stainings were less intense within the inflamed and ulcerated mucosa of pouchitis compared to the normal pouch and in close proximity to areas of re-epithelialization. Microbiota analysis showed a decreased biodiversity in pouchitis vs. normal pouch (both at pouch and ileal loop level). Lower levels of Verrucomicrobia and increased abundance of Actinobacteria were recorded in inflamed pouch vs normal pouch. In pouchitis, the ileal loop and the pouch showed decreased levels of Akkermansia muciniphila and augmented abundance of Collinsella vs. samples from the normal pouch. In pouchitis, multivariate analyses evidenced a significant inverse correlation between Collinsella e Collinsella aereofaciens abundance and ST2 levels. Conclusion Pouchitis and normal pouch are characterized by divergent inflammatory molecular pathways and microbial populations with a specific pattern between the pouch and afferent ileal loop. Our results suggest a potential role for IL-33/ST2 and gut microbiota axis in driving the gut mucosal wound healing in patients with ileal pouch-anal anastomosis.

P287 Clinical characteristics and outcomes of ileal pouch–anal anastomosis (IPAA) inflammation in a Latin American (LA) IBD reference Center (I.

Abstract Background Restorative proctocolectomy with ileal pouch–anal anastomosis (IPAA) can be associated with a wide spectrum of complications, ranging from a frequently mild acute pouchitis (AP) to Chronic pouch inflammation (CPI, either antibiotic dependent or refractory, CADP and CARP respectively) and Crohn's disease like pouch inflammation (CDLPI). The pathogenesis, still largely unknown, probably is multifactorial, and environment may play a role. We aimed to describe clinical characteristics and outcomes of IPAA inflammation in a Latin American (LA) IBD reference Center. Our main focus is CDLPI, because, despite of UC is reported more frequent in LA, epidemiology is changing, and notably, colon location (within CD) reach the half of the CD casuistic in our hospital, as well as other Argentina locations (Cordoba) and Uruguay, a neighbor Country. Probably, this epidemiological feature could impact in our patient′s evolution. Methods Our hospital has a Coloproctology Team pioneer of IPAA surgery in Argentine and as Clinical IBD Service, we performed a revision in our electronic data base (included from 1990 to current date, and detected 437 pts. with IPAA. Criteria were; modified PDAI (for disease activity), for CPI and CDLPI we adopted that of Shen B, Clin. Gastrienterol hepatol 200, 6:145-58. Results Results We compare 46 CDLPI with 24 CPI pts. (CADP and CARP) and 24 AP. A total of 55 M, 39 F, were evaluated for demographic data and disease complications. Mean age ±SD at complication: CDLPI 33.8±13.8, CPI 34.2±11.2, AP 40.1±13.7, (NS for gender and Age). Median time (IQR) up to each one of 3 complications: 1.6 (4.19), 2.09 (7.17) and 1.34 (2.67), respectively (NS, Median test). Follow–up time was similar: 20.11 (10.9), 13.7 (12.2), 13.9 (15.6), respectively. CDLPI presented inflammatory pattern in: 37 (80.4%), stricturing in 6 (13.04%), fistulizing in 16 (34.8%) Perianal complication: 43.5%. Pre-pouch ileitis in CDLP: 26 (56 5%) vs. CPI 1(4.2%), in AP 0% (p.00000), prepouch strictures (13.04% vs. 0%), significant different, as well as prepouch fistulas (17.4%), with suboclusion in 29% Pouch vaginal fistulas and pouch-cutaneous in 1/5 of patients. Cuffitis in 19%. The original IBD was more severe and extensive p &amp;lt;0.02 in the mentioned subgroup. As regard treatment, IMM treatment in CDLP: was required in 70% vs. 26% in CPI and biologics en 2/3 0.00016, 11% ≥2 biologics. Pouch failure (diversion and resection) was observed in 30% and 13% respectively. Conclusion We are a LA center with high CD prevalence. The complications of surgery must be taken into account. IPAA revolutionized UC surgery, but close monitoring, and new research are required with the future hope of acting proactively.

P205 Impact of histologic disease activity on long-term outcomes in patients with ileal pouch-anal anastomosis for ulcerative colitis

Abstract Background Total proctocolectomy with ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC) can incur in several complications like pouchitis leading to the need of immunosuppressive therapy, hospitalization and pouch failure. Unlike non-operated UC patients, therapeutic goals are an unmet need in UC-IPAA patients and the impact of the histologic activity on the development of complications is unknown. The aim of the study was to assess the association between histology and the risk of long-term negative outcomes in UC subjects with IPAA. Methods This is a single-center, retrospective study which included UC adult patients with IPAA undergoing at least one pouchscopy with biopsies in the pouch body after ileostomy closure. Pouch biopsies were blindly reviewed by a gastrointestinal pathologist with expertise in IBD. Histologic disease remission was defined as a Pouchitis Disease Activity Index (PDAI) histology subscore £ 1. Negative outcomes were: IPAA related complications (acute or chronic pouchitis, hospitalization, pouch failure) and escalation of medical therapy (start of immunosuppressive or biologics). Both descriptive and inferential statistical analyses carried out Results A total of 66 patients were included (male n=37; 56,1%) of whom 40,9% (n=27) had histological activity at the baseline pouchscopy. The characteristics of the study population are represented in table 1. The median time of follow up was 38,5 months (range 12-151). During the study period, 27 patients (40,9%) developed acute pouchitis and 10 patients (15,2%) chronic pouchitis. Thirty-nine subjects (59,1%) required antibiotic therapy while 8 subjects required systemic steroids (12,1%). Furthermore, 15 patients (22,7%) started immunomodulatory therapy with either azathioprine or biologic agents. Six patients (9,1%) needed pouch-related hospitalization and 1 patients (1,5%) experienced pouch failure. Chronic pouchitis and the need of immunosuppressive/biology therapy was observed more frequently in patients with pouch histologic activity (29,6% vs. 5,1%, and 40,7% vs. 10,3%, respectively) (P&amp;lt;0.05). After adjusting for risk factors for pouchitis, the presence of histologic activity remained an independent risk factor for developing acute pouchitis (OR 4.10, 95% CI 1.39-12.04; P= 0.010), chronic pouchitis (OR 8.51, 95% CI 1.51-47.80, P=0.015) and the need for immunosuppressive or biologic therapy (OR 6.98, 95% CI 1.69-28.80; P=0.007). Conclusion Histologic activity was associated with an increased risk of developing both acute and chronic pouchitis and with the need for immunosuppressive/biologic therapy. Future research will clarify whether histologic remission might be considered as a therapeutic target for UC-IPAA patients developing pouchitis.

DOP70 Crohn’s Disease Like Inflammation of The Pouch is a Distinct Type of Pouchitis

Abstract Background Pouchitis occurs in up to 80% of patients with ulcerative colitis (UC) after total proctocolectomy (TPC) with ileal pouch anal anastomosis (IPAA). The pathogenesis of pouchitis is unclear, but is thought to involve a complex interaction between the microbiome and mucosal immune system. To examine the underlying pathophysiological mechanisms of pouchitis, the present study aims to simultaneously define immuno-histological and microbial parameters associated with different pouch phenotypes. Methods Endoscopic biopsies from the pre-pouch ileum (PI) and the pouch body (PB) were obtained from 51 subjects age&amp;gt;18 who underwent TPC with IPAA, n=48 for UC and n=3 for familial adenomatous polyposis (FAP). Mucosal mononuclear cells (MMC) were isolated from the intra-epithelial compartment (IEC) and lamina propria (LP) and examined for lymphoid, myeloid and innate immune subsets by multiparameter flow-cytometry (FC). Histological sections were examined by two pathologists, blinded to clinical identifiers and scored for inflammatory parameters that included neutrophilic activity, lymphoplasmacytic infiltration, eosinophilia, villous atrophy and submucosal fibrosis. Metagenomic sequencing of stool was performed and analyzed for microbial beta and alpha diversity. Results IPAA subjects were classified into the following phenotypes: normal pouch (NP) n=15 (29.4%), acute pouchitis (AP) n=9 (17.6%), chronic antibiotic dependent pouchitis (CADP) n=9 (17.6%), Crohn’s disease like pouch inflammation (CDLPI) n=15 (29.4%), and FAP NP n=3 (5.9%). Among subjects with NP, the PB had a higher frequency of naïve-CD4+ and CD8+ T cells, central memory- CD4+ T cells, and naïve B cells and a lower frequency of homeostatic IELs relative to the PI (Fig. 1A). Immune remodeling of the PB was further confirmed on histology that demonstrated increased lymphoid aggregates and decreased IELs. Subjects with CDLPI had significantly higher levels of inflammation, chronicity, and lymphoid aggregates but decreased IELs in the PI than NP or AP patients (Fig. 1B and 1C). In contrast to immune parameters, the composition of the microbiota in non-inflamed UC pouches was more similar to inflamed UC pouches than to FAP pouches. Alpha diversity and genus relative abundance differences between UC and FAP pouch stool samples were not statistically significant (Fig. 1D). Conclusion CDLPI represents a distinct entity of pouchitis that is associated with heightened levels of chronic inflammation relative to AP despite similarities in microbiota.

P598 The utility of the “Low Anterior Resection Syndrome SCORE” in assessing the postoperative outcomes of patients undergoing restorative proctocolectomy with ileal pouch anal-anastomosis for Ulcerative Colitis

Abstract Background Restorative proctocolectomy with ileal pouch anal anastomosis (IPAA) in a J-pouch configuration is the treatment of choice for patients with ulcerative colitis. Some patients who have undergone this surgery present symptoms including fecal or gas incontinence, urgency, clustering, and frequency, that occurs after anal sphincter-sparing surgery for the treatment of rectal cancer. There is a lack in standardization and evaluation of functional outcomes. Our aim is to evaluate the effectiveness of the LARS (low anterior resection syndrome) score in this cohort of patients. Methods We conducted a retrospective analysis of a prospectively maintained single center database. We assessed the quality of life by using the Inflammatory Bowel Disease Questionnaire (IBDQ-32). The functional bowel complaints were assessed using the LARS score. Results Between 2015 and 2020, 70 patients with ulcerative colitis underwent total colectomy and subsequent IPAA with J-Pouch configuration. Among these, 49 patients who closed the ileostomy and were followed for at least 6 months, were selected for the present study. Nineteen patients did not have the LARS; among 30 who complained the LARS, 17 had a major LARS (tab.1). The latter had a worse quality of life on the IBDQ-32 questionnaire, especially in relation to urgency and frequency (Fig.1). We compared the two scores using Spearman's test correlation coefficient, detecting a significant correlation (rho -0.7664185; p-value &amp;lt;0.005); a significant correlation between the urgency sub-category with LARS score (rho -0.6515759; p-value &amp;lt;0.005) and frequency (rho -0.6744705; p-value &amp;lt;0.005) was evaluated. Tab 1: Patients characteristics: Fig.1:IBDQ-32 value in different LARS categories Conclusion In our experience LARS score appears to be a useful, effective and simple tool to predict functional outcomes and QoL not only in oncological rectal sphincter-sparing surgery but also in functional surgery for ulcerative colitis.