EP667 - Risk Factors Associated with Failed Anal Dilations Requiring Anal Stricturotomy in Anal Stenosis in Inflammatory Bowel Disease

Purpose/Background: Anal stenosis is a notable yet underrecognized complication in patients with inflammatory bowel disease (IBD). Management of anal stenosis often begins with mechanical dilation, which has been shown to be safe and effective. If conservative measures fail, surgical options such as anoplasty or sticturotomy may be considered to restore function. The purpose of the study is to compare risk factors associated with treatment failure of anal dilation requiring stricturotomy in patients with IBD and anal stenosis.

Methods/Interventions: A single institution retrospective review was performed to evaluate patients diagnosed with IBD and anal stenosis. Inclusion criteria included patients with IBD who aged 18 years and older who were treated for anal stenosis at the University of Kentucky from January 2019 to June 2025. The primary endpoint assessed patients who failed anal dilation and required a stricturotomy. Demographics were compared between the two groups to identify risk factors for failure of dilations including biologic sex, smoking status, body mass index (BMI), Rural-Urban Commuting Area (RUCA) score, biologic therapy, and history of interruptions in biologic therapy. Statistical analyses were performed using Jamovi. Univariate analyses were conducted using χ² or Fisher's exact tests for categorical data and independent t-tests or Mann-Whitney U tests for continuous data. Statistical significance was defined as p < 0.05.

Results/Outcomes: A total of 65 patients met inclusion criteria and underwent anal dilations for the management of anal stenosis. Twelve patients (18.5%) failed anal dilations and subsequently required a stricturotomy. Patients who required a stricturotomy failed after a median of 2.5 dilations (p = 0.011). Patients with Crohn's disease were more likely to require a stricturotomy (12 of 36 patients) compared to those with ulcerative colitis (0 of 17 patients) (p = 0.02). There were no statistically significant differences in biologic sex ( p=0.95), race (p=1), smoking history (p=0.35), BMI (p=0.77), (RUCA)RUCA score (p = 0.161), or insurance type (p = 0.329) in patients who required a stricturotomy. Although there was no significant difference in the incidence of patients on biologic therapy at the time of initial intervention (11 of 49 patients on biologic therapy vs 1 of 16 patients not on biologic therapy required a stricturotomy, p = 0.266), patients who experienced interruptions in their biologic treatment may be more likely to require stricturotomy (7 of 35 patients with interruption of biologic therapy vs 5 of 15 patients with no interruption of biologic therapy required stricturotomy, p=0.06).

Conclusion/Discussion: Demographic and clinical factors, including sex, BMI, smoking history, RUCA score, race, insurance status, and biologic therapy at the time of initial intervention were not associated with an increased risk of requirement of a stricturotomy. The patients who appear at highest risk of undergoing a stricturotomy are those diagnosed with Crohn's disease requiring more than 2.5 dilations. Additionally, patients who have had interruptions in their biologic treatment may be at increased risk for failing anal dilations. This data allows for stratification of patients who are more likely to require a stricturotomy and can guide management as well as facilitate expectations of management with patients.