Colonic regular contractile frequency patterns in irritable bowel syndrome: the 'spastic colon' revisited

Background Irritable bowel syndrome is a frequent gastrointestinal disorder of which the pathophysiological basis is still not completely understood. Among the various proposed mechanisms, colonic motility may play a role, at least in a subset of patients. Aims To investigate the regular colonic contractile patterns in patients with irritable bowel syndrome. Our working hypothesis was that an increase of these patterns in such condition might represent a motility equivalent of the so-called 'spastic colon'. Patients and methods Twelve patients of both genders were investigated by means of 24 h colonic manometry, and the results were compared to those from 20 healthy controls. Regular contractile patterns (with frequencies ranging from 2 to 8 per min) were calculated for the entire recording period and in single colonic segments. Results Overall, colonic frequency patterns were significantly more frequent in patients than controls (12.6% vs 6.4% of the total contractile activity, P < 0.001); in both groups, the 3 cycles/min frequency was predominant, especially in the sigmoid colon. More than 40% patients displayed a correlation between abdominal pain and occurrence of regular contractile frequencies. Conclusions Abnormal colonic motility may play some role in the pathogenesis of symptoms related to irritable bowel syndrome, with an excess of regular contractile activity related to the so-called 'spastic colon'. (C) 2004 Lippincott Williams Wilkins.