Prevalence of ‘pouch failure’ of the ileoanal pouch in ulcerative colitis: a systematic review and meta-analysis

Background and aims The ileoanal pouch (IPAA) provides patients with ulcerative colitis (UC) that have not responded to medical therapy an option to retain bowel continuity and defecate without the need for a long-term stoma. Despite good functional outcomes, some pouches fail, requiring permanent diversion, pouchectomy, or a redo pouch. The incidence of pouch failure ranges between 2 and 15% in the literature. We conducted a systematic review and meta-analysis aiming to define the prevalence of pouch failure in patients with UC who have undergone IPAA using population-based studies. Methods We searched Embase, Embase classic and PubMed from 1978 to 31st of May 2021 to identify cross-sectional studies that reported the prevalence of pouch failure in adults (≥ 18 years of age) who underwent IPAA for UC. Results Twenty-six studies comprising 23,389 patients were analysed. With < 5 years of follow-up, the prevalence of pouch failure was 5% (95%CI 3–10%). With ≥ 5 but < 10 years of follow-up, the prevalence was 5% (95%CI 4–7%). This increased to 9% (95%CI 7–16%) with ≥ 10 years of follow-up. The overall prevalence of pouch failure was 6% (95%CI 5–8%). Conclusions The overall prevalence of pouch failure in patients over the age of 18 who have undergone restorative proctocolectomy in UC is 6%. These data are important for counselling patients considering this operation. Importantly, for those patients with UC being considered for a pouch, their disease course has often resulted in both physical and psychological morbidity and hence providing accurate expectations for these patients is vital.

Microbiome Analysis of Mucosal Ileoanal Pouch in Ulcerative Colitis Patients Revealed Impairment of the Pouches Immunometabolites

The pathogenesis of ulcerative colitis (UC) is unknown, although genetic loci and altered gut microbiota have been implicated. Up to a third of patients with moderate to severe UC require proctocolectomy with ileal pouch ano-anastomosis (IPAA). We aimed to explore the mucosal microbiota of UC patients who underwent IPAA. Methods: For microbiome analysis, mucosal specimens were collected from 34 IPAA individuals. Endoscopic and histological examinations of IPAA were normal in 21 cases, while pouchitis was in 13 patients. 19 specimens from the healthy control (10 from colonic and 9 from ileum) were also analyzed. Data were analyzed using an ensemble of software packages: QIIME2, coda-lasso, clr-lasso, PICRUSt2, and ALDEx2. Results: IPAA specimens had significantly lower bacterial diversity as compared to normal. The microbial composition of the normal pouch was also decreased also when compared to pouchitis. Faecalibacterium prausnitzii, Gemmiger formicilis, Blautia obeum, Ruminococcus torques, Dorea formicigenerans, and an unknown species from Roseburia were the most uncommon in pouch/pouchitis, while an unknown species from Enterobacteriaceae was over-represented. Propionibacterium acnes and Enterobacteriaceae were the species most abundant in the pouchitis and in the normal pouch, respectively. Predicted metabolic pathways among the IPAA bacterial communities revealed an important role of immunometabolites such as SCFA, butyrate, and amino acids. Conclusions: Our findings showed specific bacterial signature hallmarks of dysbiosis and could represent bacterial biomarkers in IPAA patients useful to develop novel treatments in the future by modulating the gut microbiota through the administration of probiotic immunometabolites-producing bacterial strains and the addition of specific prebiotics and the faecal microbiota transplantation.

EP.TU.911Analysis of the outcomes following reversal of loop ileostomy

Aims A defunctioning loop ileostomy is constructed to reduce the incidence and the consequences of anastomotic leaks following sphincter-sparing colorectal resection. Its construction and reversal may be associated with complications. The aim of this study is to present a snapshot of the outcome of reversal of loop ileostomy in a teaching general hospital. Methods All patients whose loop ileostomy was reversed in 2018 were studied. Sociodemographic and clinical data were collected. The outcomes measured were length of hospital stay, return of bowel function, morbidity and mortality. Results Nine patients had reversal of ileostomy by experienced colorectal surgeons during this period. The patients, 5 males and 4 females, had a median age of 58 years (range 20 to 77 years). The main indications for construction of a loop ileostomy were low anterior resection for rectal neoplasia (7 patients) and iatrogenic rectal perforation during hysterectomy (1 patient), and total colectomy with ileoanal pouch reservoir for ulcerative colitis (1 patient). The ileostomies were reversed between 5 to 10 months following the main operations. The postoperative stay was between 2 to 12 days. The complications included one anastomotic leak, requiring immediate re-operation, 3 wound infections and 2 incisional hernias. There were no postoperative deaths. Conclusion In this study our overall complication rate was well within the range reported in the literature, with only one patient requiring immediate re-operation. The presence of a senior colorectal surgeon at operation as well as careful attention to detail is key to keeping complications to a minimum.

SP7.2.1 Simultaneous intestinal surgery does not increase complication or recurrence rates after complex abdominal wall reconstruction

Aims To compare post-operative outcomes in patients undergoing elective complex abdominal wall reconstruction (CAWR) alone vs. CAWR plus simultaneous intestinal surgery. Methods All patients undergoing elective CAWR over a 10-year period in our unit were identified from a prospectively maintained database and divided into those who had concomitant intestinal surgery (resection, ileoanal-pouch formation, stoma reversal, etc) and those who did not. Simple adhesiolysis, cholecystectomy and gynaecological procedures were not classed as ‘intestinal surgery’. Differences between groups were determined using the paired-t test and the (n-1) Chi-squared test. Results 59 patients underwent elective CAWR, 16 with intestinal surgery and 43 without. The two groups had similar baseline demographics with no significant differences in age, BMI, sex or hernia size. The commonest post-operative complications were pneumonia (33.9%) and wound infections (25.4%) but there were no significant differences in any complication between groups. There was zero 30 and 90 day mortality in either group. The mean operating time in the intestinal group (IG) was significantly longer compared to the CAWR-only group (5.4 +/- 1.3hrs vs 4.1 +/- 1.8hrs, p = &lt;0.05). There was no statistically significant difference between groups in rates of surgical site occurrence (37.5% IG vs 55.81% CAWR-only), mesh infections (0% IG vs 6.98% CAWR-only) or recurrent hernia (6.24% IG vs 9.30% CAWR-only) over a median follow up of 3.0 (0.1-7.8) years. Conclusion Performing simultaneous intestinal surgery during complex abdominal wall repair is safe and does not increase the risk of recurrence or mesh infections in a specialist abdominal reconstruction unit.