Chronic anastomotic sinus after low anterior resection: when can the defunctioning stoma be reversed?

Aim Anastomotic leakage after low anterior resection may incompletely resolve, resulting in sinus tracts that persist on repeated contrast studies. This case series evaluated the factors that may contribute to sinus healing or to safe reversal of the defunctioning ileostomy. Method All patients (n = 8) who developed an anastomotic sinus after low anterior resection over an 8-year period were identified from a prospective database. Results All patients had been treated with low anterior resections with defunctioning stomas for rectal carcinoma [median follow up 43.5 (13-84) months]. Two patients with an unhealed subclinical leak had the stoma reversed successfully. Of the six patients with clinical leakage, two healed spontaneously, one healed after application of fibrin glue, one developed an anastomotic stricture that was successfully treated by dilatation with subsequent stoma reversal, and one developed recurrent cancer and was not reversed. One patient underwent reversal, despite persistence of the sinus, followed by rectal perforation requiring laparotomy and faecal diversion. Bowel function was satisfactory where the sinus healed spontaneously, but poor where reversal was carried out without sinus healing. Conclusion Tracks that persist for longer than 1 year are unlikely to heal, but the stoma can be reversed if there had been a subclinical leak previously. A persistent anastomotic sinus leading to a cavity may not be suitable for stoma closure.