Gut transit time after ileal pouch-anal anastomosis using a radiopaque marker.

Purpose: The aim of this study was to determine the contribution of gastrointestinal motility to bowel function and the pathogenesis of pouchitis after ileal pouch-anal anastomosis.

Methods: Gastrointestinal transit time was assessed by a radiopaque marker technique in 32 patients with ulcerative colitis.

Results: Small intestinal transit time and pouch emptying time were 4.1 +/- 2 hours and 4.1 +/- 2.5 hours, respectively. There was no significant difference in pouch emptying time between patients with and without pouchitis. When only patients with acute pouchitis that responded to metronidazole were analyzed, there was a trend toward a prolonged pouch emptying time compared with those without pouchitis (P = 0.095). Whole gut transit time was inversely correlated with 24-hour stool frequency in patients without pouchitis (r = -0.63, P < 0.005). In the analysis of regional transit time, only small intestinal transit time was inversely correlated with 24-hour stool frequency (r = -0.472, P < 0.05). Significant prolongation of small intestinal transit time was demonstrated in patients over a period of 41 months (the median time) after ileostomy closure compared with those whose pouches had been functioning for 6 to 41 months (5.4 +/- 1.7 hours vs. 3.1 +/- 1.3 hours, P < 0.005).

Conclusions: There was an association between small intestinal motility and bowel frequency. Further investigation is necessary in the pathogenesis of acute pouchitis regarding the relationship between delayed pouch emptying and subsequent development of mucosal inflammation.