L'anastomose iléo-anale dans la rectocolite ulcéro-hémorragique et la polypose adénomateuse familiale : faut-il faire une mucosectomie endo-anale de principe ?

The aim of this study was to assess the clinical outcome after ileal pouch-anal anastomosis with mucosectomy for ulcerative colitis and for familial adenomatous polyposis, and to characterize the histology of the stripped endoanal mucosa with particular reference to the ulcerative colitis activity, adenomatous polyps and dysplasia. Twenty-eight patients were operated, 16 for ulcerative colitis (group I) and 12 for familial adenomatous polyposis (group II). In group I, there were no intraoperative complications, but mucosectomy was tedious in 10 patients (62 %) and the anastomosis was performed under some degree of tension in 10 patients (62 %). In group II, there was a direct injury of the internal sphincter by a posterior tear during the mucosal stripping in one case. Mucosectomy was easy to perform in 8 patients (67 %) and 10 anastomoses (84 %) were performed under tension. In both groups, there were no postoperative complications related to the mucosectomy or to the anastomosis itself. Functional results were good, with a normal continence in 80 % of ulcerative colitis patients and 92 % of familial adenomatous polyposis patients. Review of histological sections of the stripped anal mucosa in group I showed chronic active ulcerative colitis in 8 patients (50 %), chronic non-active ulcerative colitis in 4 (25 %) and quiescent ulcerative colitis in 4 (25 %). There was only one case of moderate dysplasia in a patient with a Dukes A carcinoma. In group II, anal mucosa showed micropolyps in all cases with mild dysplasia in 3 cases (25 %) and moderate dysplasia in 9 (75 %). In conclusion, a careful mucosectomy does not affect the surgical outcome and the functional results of ileal pouchanal anastomosis. Since removal of the disease is more complete, the anal mucosa should always be removed down to the level of the dentate line in restorative proctocolectomy for ulcerative colitis and for familial adenomatous polyposis