Is there a difference in the outcomes of long-term seton placement for complex anal fistula in patients with and without Crohn's disease?

BACKGROUND: Management of complex anal fistulas is challenging. Draining-setons are commonly used to control sepsis and prepare for surgery. This study compared outcomes of seton placement in patients with and without Crohn's disease (CD). METHODS: We retrospectively reviewed patients with complex anal fistulas undergoing non-cutting seton placement (2013-2022), without plans for definitive surgery. The primary outcome was one-year seton failure, defined as recurrent abscess, new fistula, or need for reintervention. Multivariate analysis identified factors associated with failure. RESULTS: Ninety-nine patients were included (73 CD, 26 non-CD). One-year seton failure was higher in CD patients (58% vs. 23%, p = 0.003), driven by increased fistula formation and need for additional setons. On multivariate analysis, CD (HR 2.5), family history of IBD (HR 2.3), prior anorectal surgeries, and steroid use (HR 3.2) were associated with failure. CONCLUSION: Seton outcomes are worse in CD, supporting its role as a temporizing rather than definitive treatment strategy.