title: Abnormalities of left colonic motility in ambulant nonconstipated patients with irritable bowel syndrome.
abstract: Our objective was to evaluate left colonic motility patterns recorded under physiological conditions during 24 hr in fully ambulant nonconstipated IBS patients compared to healthy controls. A 42-hr manometry of the left colon was performed in 11 nonconstipated IBS patients and 10 age- and sex-matched healthy volunteers. On day 1, a 6-channel, 10-cm interval, solid-state catheter was positioned. Frequency, amplitude, and motility index (MI) of segmenting pressure waves in the descending and sigmoid colon were calculated during the 24-hr study period on day 2. High-amplitude propagated contractions (HAPCs) were identified visually and their characteristics were calculated. In IBS patients a higher frequency of segmenting pressure waves was observed in the sigmoid colon compared to the descending colon (P = 0.006). In contrast, no regional differences were observed in controls. Awakening (P = 0.048) as well as having a meal (P = 0.024) was associated with a smaller increase of contraction frequency in the descending colon of IBS patients compared to controls. HAPCs occurred more frequently in IBS patients than in controls (P = 0.035). HAPCs in IBS patients reached a more distal colonic level and occurred more frequently in clusters. Defecation in IBS patients, but not in controls was always preceded by a cluster of HAPCs. In conclusion, left colonic segmenting pressure waves and HAPC characteristics are altered in nonconstipated IBS patients.
authors.affiliation: Gastrointestinal Research Unit, Department of Gastroenterology, University Medical Center Utrecht, The Netherlands.
authors.forename: C H M
authors.initials: CH
authors.lastname: Clemens
authors.forename: M
authors.initials: M
authors.lastname: Samsom
authors.forename: G P
authors.initials: GP
authors.lastname: Van Berge Henegouwen
authors.forename: A J P M
authors.initials: AJ
authors.lastname: Smout
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002940:Circadian Rhythm; D003106:Colon / Q000503:physiopathology*; D003109:Colonic Diseases, Functional / Q000503:physiopathology*; D003248:Constipation; D003672:Defecation / Q000502:physiology; D005260:Female; D005769:Gastrointestinal Motility / Q000502:physiology*; D006801:Humans; D015994:Incidence; D008297:Male; D008365:Manometry