Timing of seton removal and clinical outcomes in perianal fistulizing Crohn's disease: A systematic review and meta-analysis.

Abstract

The optimal timing for seton removal in perianal fistulizing Crohn's disease (PFCD) remains unclear. Therefore, we examined the range of reported timing strategies and their association with clinical outcomes. We systematically searched PubMed, Web of Science, Cochrane Library and Ichushi-Web for studies published from January 1990 to June 2025. Eligible studies included adult patients with PFCD who underwent seton placement and reported removal timing and clinical outcomes. Healing and recurrence rates were pooled using a random effects model. Subgroup analyses evaluated seton removal timing (<34 vs. ≥34 weeks) and biologic and antibiotic usage. Overall, nine studies were included (nine observational studies). The pooled healing rate was 57% (95% confidence interval [CI], 40-73%), and the pooled recurrence rate was 31% (95% CI, 15-53%), both with substantial heterogeneity (I² > 80%). Short-term removal (<34 weeks) achieved a healing rate of 69% (95% CI, 56-79%) vs. 46% (95% CI, 22-72%) for long-term removal (≥34 weeks) (p = 0.03). A significant correlation was found between seton removal timing and healing rate (r = -0.70, p = 0.03). The recurrence incidence was 12.7 (95% CI, 4.7-34.3) in the short-term group and 3.9 (95% CI, 0.7-21.4) in the long-term group (p = 0.09). An association between seton removal timing and fistula healing was observed without a corresponding increase in recurrence. These findings should be interpreted cautiously because removal timing may reflect disease severity and treatment response rather than a causal effect.