Op-2 the Diagnostic Value of Radiological Colonic Transit Study Compared with High-resolution Colonic Manometry.

BACKGROUND Chronic constipation is one of the most common chronic disease in children. Most of cases are functional, however some has problem of organic myopathic or neuropathic colon. Colonic transit study with oro-anal transit markers is the basic diagnostic tool for colonic dysmotility in clinical practice, colonic manometry is the recommended investigation in the next step. Nevertheless, the colonic manometry is considered more invasive, expensive and also unavailable in many countries. The aim of this study is to assess the diagnostic value of conventional method as colonic transit study compared with the novel high-resolution colonic manometry in diagnose colonic abnormalities. METHODS Fifty constipated children in Great Ormond Street hospital were retrospectively reviewed in demographic data and investigation result. The diagnosis of constipation was based on history and physical examination which followed Rome III criteria. All of enrolled patients received colonic manometry investigation before colonic transit study in order to reduce the bias. For colonic transit protocol, patients had to ingest a 10-markers capsule on 3 consecutive days and an abdominal x-ray was obtained on day 4. The cut-off values for abnormal segmental and total colonic transit time(CTT) were based on Arhan et al publication. RESULTS Fifty constipated children with the mean age of 9.77 years (1.15-17.32) were included. Of all, 39(78%) patients had colonic abnormality detected by colonic manometry while 38(76%) patients had abnormal CTT.The sensitivity, specificity, and positive predictive value(PPV) of colonic transit study for abnormal total CTT were 46.2%, 72.7% and 85.7%, respectively. In aspect of abnormal segmental CTT, the sensitivity, specificity and PPV of right colon are 66.7%, 63.6% and 20%; left colon are 16.7%, 72.7% and 7.69%; and rectosigmoid colon are 29.4%, 68.8% and 66.7%, respectively. CONCLUSIONS Colonic transit study seemed to have satisfied posttest probability to diagnose total colonic abnormality. However, for segmental CTT, this test might be invalid and the consideration to use as predictor of segmental abnormality was not recommended.