Comparing the Colonic Transit Time in Constipation Predominant Irritable Bowl Syndrome and Functional Constipation

Functional constipation (FC) and constipation-predominant irritable bowl syndrome (CIBS)are two main subtypes of constipation that can be distinguished by the Rome II criteria. Measuring colonic transit time (CTT) is an easy and cost effective way to evaluate constipation. This study was conducted to compare the CTT in patients with FC and CIBS.Those patients who referred to our hospital with complaint of chronic constipation were studied and those with no organic disease were included in this study. Using the Rome II criteria, they were then categorized as having FC or C-IBS. All patients ingested 10 radioopaque markers daily for six days. A plain abdominal x-ray was taken on the seventh day. Markers in the right and left hemicolon and rectosigmoid were counted and the total and segmental transit times were calculated and reported in hours.A total of 45 patients with FC and 45 with C-IBS were enrolled into this study. The total CTT was normal in 42% of those with FC and in 55% of those with C-IBS. The mean total CTT was not significantly different between the two studied groups. Nonetheless, the mean rectosigmoid transit time of patients with FC was significantly higher than those with C-IBS (p=0.008). There was no significant difference between the right and left hemicolon transit time.Although the CTT of patients with FC might be higher than those with C-IBS, it seems that applying the Rome II criteria to distinguish these two groups does not affect the selection of treatment strategy.