Grant: CAG/CCFC/CIHR Summer Studentship for Research in Gastroenterology

BACKGROUND: Irritable bowel syndrome (IBS) is a common functional bowel disorder, characterized by abdominal pain, discomfort, bloating and altered bowel function in the form of constipation or diarrhea. IBS can have a profound effect on quality of life and contributes to work absenteeism and impaired ability to enjoy daily activity. IBS has been associated with a disruption of the gut-brain axis and abnormal immune activation in the colonic mucosa. Since there are no symptoms specific for IBS, its diagnosis requires that patients present with certain symptoms (eg Rome III diagnostic criteria) and no relevant abnormalities on examination or investigation. However, recent research suggests that biochemical, microbial, inflammatory and immunological changes in the colon may play a role in the pathogenesis of IBS. METHODS: In a prospective pilot study, patients recruited will be undergoing colonoscopy for lower gastrointestinal (GI) symptoms including diarrhea, constipation and abdominal pain. Symptoms would be characterized using the 'Rome III' criteria. Patients undergoing colonoscopy will undergo other tests, including biopsies to assess colonic inflammation, stool analysis to evaluate colonic flora, blood tests, autonomic neural testing and GI symptom evaluation. DATA ANALYSIS: We will identify patients with and without inflammation and determine whether they differ with respect to type and severity of symptoms, their psychological state their brain-gut axis. APPLICATIONS: We aim to elucidate immunological, autonomic neural and psychological mechanisms associated with the generation of IBS-like symptoms. We will, thereby, elucidate further the pathophysiology of IBS-like symptoms to supplement traditional symptom-related diagnostic criteria with objective physical tests. The long-term goal is to develop reliable diagnostic and symptom assessment tools for IBS as a basis for developing and testing novel treatments for this common disorder.