Alteration in intestinal permeability after ileal pouch-anal anastomosis

The physiologic changes that occur when the small bowel is used as a reservoir, as in the ileal pouch-anal anastomosis, are poorly understood. Alterations in bowel permeability, which may lead to bacterial translocation that could result in illness or dysfunction of the pouch, may be one such consequence of the pouch procedure.

Whole-bowel permeability was evaluated in patients with and without the pouch through the use of an orally consumed nonmetabolizable sugar clearance technique. Patients in whom the ileal pouch-anal anastomosis was performed for ulcerative colitis (17 patients) and patients with familial polyposis (7 patients) were compared with normal healthy volunteers (10 patients) and patients with ulcerative colitis with and without curative colectomy and ileostomy (6 and 5 patients, respectively).

Measured by this technique, no differences were noted in bowel permeability between the volunteers and patients with ulcerative colitis, even after colectomy and ileostomy (1.7 +/- 0.4 in normal healthy volunteers, 1.8 +/- 0.5 in patients with ulcerative colitis without stoma, and 1.4 +/- 0.2 in patients with ulcerative colitis with ileostomy). The group of patients with an ileal reservoir, however, had a significantly increased index of measured bowel permeability (3.5 +/- 0.5 in patients with ulcerative colitis and 5.1 +/- 0.7 in patients with familial polyposis; P < 0.05 by analysis of variance compared with normal healthy volunteers and patients with ulcerative colitis with or without ileostomy).

The exact site, cause, and consequence of this possible alteration of bowel permeability are unclear but appear to be related to the presence of the pouch and are not caused by the underlying pathologic diagnosis.