Outcome of surgical treatment for fistula in ano in Crohn's disease

Background: Recurrence rates and long-term functional outcome after surgical treatment of anal fistula in Crohn's disease were assessed.

Methods: A consecutive series of patients was treated for Crohn's fistula in ano; those without proctitis or active sepsis underwent surgery. Sex, seton usage, infliximab, previous fistula surgery, history of segmental resection and smoking were examined as risk factors for recurrence. Continence was assessed by Vaizey scale and a colorectal Functional outcome questionnaire. Results were compared with institutional data for cryptoglandular fistulas.

Results: Sixty-one patients were included, with a median follow-up of 79 (range 13-140) months. Twenty-four patients were treated with a seton, 28 by fistulotomy and nine by mucosal advancement. For low fistulas, fistulotomy was used more frequently than the seton, whereas seton drainage was used for most higher fistulas. Recurrence occurred in five of 28 and five of nine patients after fistulotomy and advancement respectively. Soiling was reported by half of the patients treated by seton versus two-thirds and three-quarters of those treated by fistulotomy and advancement respectively. Functional outcomes were worse for all patient groups than for cryptoglandular fistulas. No risk factor was significant.

Conclusion: Surgical outcome for high or complex Crohn's fistula in ano remains disappointing, and recurrence is unpredictable.