Surgery for fistula-in-ano in a specialist colorectal unit: a critical appraisal

Several techniques have been described for the management of fistula-in-ano, but all carry their own risks of recurrence and incontinence. We conducted a prospective study to assess type of presentation, treatment strategy and outcome over a 5-year period.

Between 1st January 2005 and 31st March 2011,247 patients presenting with anal fistulas were treated at the University Hospital Tor Vergata and were included in the present prospective study. Mean age was 47 years (range 16-76 years); minimum follow-up period was 6 months (mean 40, range 6-74 months).Patients were treated using 4 operative approaches: fistulotomy, fistulectomy, seton placement and rectal advancement flap. Data analyzed included: age, gender, type of fistula, operative intervention, healing rate, postoperative complications, reinterventions and recurrence.

Etiologies of fistulas were cryptoglandular (n = 218), Crohn's disease (n = 26) and Ulcerative Colitis (n = 3). Fistulae were classified as simple -intersphincteric 57 (23%), low transphincteric 28 (11%) and complex -high transphicteric 122 (49%), suprasphincteric 2 (0.8%), extrasphinteric 2 (0.8%), recto-vaginal 7 (2.8%) Crohn 26 (10%) and UC 3 (1.2%).The most common surgical procedure was the placement of seton (62%), usually applied in case of complex fistulae and Crohn's patients.Eighty-five patients (34%) underwent fistulotomy, mainly for intersphincteric and mid/low transphincteric tracts. Crohn's patients were submitted to placement of one or more loose setons.The main treatment successfully eradicated the primary fistula tract in 151/247 patients (61%). Three cases of major incontinence (1.3%) were detected during the follow-up period; Furthermore, three patients complained minor incontinence that was successfully treated by biofeedback and permacol injection into the internal anal sphincter.

This prospective audit demonstrates an high proportion of complex anal fistulae treated by seton placement that was the most common surgical technique adopted to treat our patients as a first line. Nevertheless, a good outcome was achieved in the majority of patients with a limited rate of faecal incontinence (6/247 = 2.4%). New technologies provide promising alternatives to traditional methods of management particularly in case of complex fistulas. There is, however, a real need for high-quality randomized control trials to evaluate the different surgical and non surgical treatment options.