Medication Use Among Patients With Pouchitis After Total Proctocolectomy With Ileal-Pouch Anal Anastomosis for Ulcerative Colitis: A Retrospective Cohort Study

Background: The development of pouchitis after total proctocolectomy with ileal pouch-anal anastomosis (IPAA) in ulcerative colitis has been associated with exposure to anti – tumor necrosis factor agents. These agents are postulated to disrupt the gut microbiome and host local immunity with subsequent higher risk of pouchitis development. Antibiotics are the mainstay of treatment for pouchitis, implicating the pathogenic role of intestinal bacteria. We performed a retrospective cohort study to assess the prevalence of pouchitis, rates of biologic and antibiotic use among patients at our institution after total proctocolectomy with IPAA for ulcerative colitis. Methods: The study was approved by the Institutional Review Board at the University of South Florida (USF). All consecutive patients at the USF Inflammatory Bowel Diseases center with a diagnosis of ulcerative colitis who underwent total proctocolectomy with ileal pouch-anal anastomosis (IPAA) at any point in time were eligible for inclusion. Exclusion criteria included an initial diagnosis of Crohn’s disease and surgery other than IPAA. Primary outcome was prevalence of pouchitis among patients at our institution after IPAA. Secondary outcomes included rates of acute vs recurrent pouchitis, biologic/small molecule, and antibiotic use. Demographic, clinical and surgical data were extracted from the electronic medical records. Results were summarized as rates/percentages for categorical variables and mean/median with standard deviation (SD) for continuous variables. The difference in categorical variables across the compared groups was assessed using binary logistic regression and summarized as odds ratio (OR) along with 95% CI. Kaplan-Meier curve was calculated for time dependent variables. All data analysis was performed using IBM SPSS version 28 statistical analysis package. Results: 100 patients met the inclusion criteria. The prevalence of pouchitis was 72%. Of patients with pouchitis, 35% (25) had isolated acute pouchitis and 65% (47) had recurrent pouchitis. There was no significant difference in rates of anti-TNF therapy (48.6% vs 60.7, p=0.37) or other biologic/small molecule use (80.3% vs 88.9%, p=0.18) prior to IPAA in patients with vs without pouchitis, respectively. Ciprofloxacin (87% vs 48%, p=0.001) and metronidazole (77% vs 52%, p=0.06) were most commonly used antibiotics, with significantly increased use in patients with recurrent versus acute pouchitis. The prevalence of chronic antibiotic use was similar among patients with pouchitis (17%). Among patients with pouchitis, the prevalence of new immunosuppressive therapy was 76%, similar between subgroups (68% of acute vs 81% of recurrent, p=0.25). The majority of patients were started on ustekinumab (24%), vedolizumab (22%), then risankizumab (14%) after IPAA. Conclusions: The findings from our study show no statistically significant association between pouchitis development and exposure to anti-TNF therapy. Immunosuppressive therapy remains the treatment standard for these patients and should not be limited. Increased use of antibiotics prior to IPAA was found in recurrent pouchitis patients. More studies need to be completed to determine prognostic factors for acute and recurrent pouchitis development in UC patients after IPAA.