Little is known concerning colonic motility and almost nothing is known concerning propulsive activity in pathological conditions characterized by diarrhea of both inflammatory and non-inflammatory origin.

The purpose of the present study was to investigate colonic propulsive activity in ulcerative colitis and diarrhea-predominant irritable bowel syndrome (IBS) patients.

Seven patients with active, moderate ulcerative colitis and nine diarrhea-predominant IBS patients entered the study. Sixteen healthy volunteers were recruited as a control group. In all subjects, 24-h colonic motility was recorded by a colonoscopically positioned manometric catheter. Both high- (mass movements) and low-amplitude propagated contractions were analyzed.

High-amplitude propagated contractions were significantly increased in ulcerative colitis with respect to controls; no significant differences were found with respect to IBS patients, and between IBS and controls. Concerning amplitude, no significant difference was found between groups, although IBS patients approached the statistical difference with respect to controls. Low-amplitude propagated contractions were significantly increased in ulcerative colitis with respect to controls; no significant differences were found compared with IBS patients. The latter, however, displayed a trend toward an increase with respect to controls that approached but did not reach statistical significance.

Both inflammatory and non-inflammatory diarrheal conditions are characterized by an overall increase of colonic propulsive activity. This observation may be useful for a better understanding of the pathophysiologic mechanisms of these disorders.