Long-term outcomes after seton placement for perianal fistulas with and without Crohn's disease

Perianal sepsis in Crohn's disease (CD) fistulas is managed with antibiotics and surgical drainage; a noncutting seton is used for an identified transsphincteric fistula tract. The optimal management following seton placement for initial control of perianal sepsis remains to be determined. Our main aim was to assess the success rates of curative surgery, seton removal or long-term indwelling seton in patients with and without CD.

This was a retrospective cohort of consecutive patients with a perianal fistula treated with a noncutting seton between 2010 and 2019, including 83 CD patients and 94 patients without CD. Initial control of symptomatic perianal infection with a seton and subsequent healing and reintervention rates were compared between the three postseton management strategies.

A total of 177 patients, 61% male and 83.1% with complex fistulas, were followed for a median of 23 months (interquartile range 11-40 months). Immunomodulatory treatment was used in 90.4% of CD patients after seton placement. Good initial control of perianal infection was achieved with a seton in CD and non-CD patients, at 92.9% and 96.7%, respectively (p = 0.11). Overall fistula healing or control for CD and non-CD patients was, respectively, 64% and 86% (p = 0.1) after curative surgery, 49% and 71% after seton removal (p = 0.21) and 58% and 50% with long-term seton placement (p = 0.72). Overall reintervention for recurrence was 83% in CD versus 53.1% in non-CD patients during the follow-up period (p = 0.002).

Definitive surgery was possible in only a minority of CD patients. Long-term seton management was an effective option in patients with CD with acceptable improvement and recurrence rates.