CHRONIC DIARRHEA;

Objective: To determine the frequency of large bowel causes of chronic diarrhea in adult Pakistani patients. StudyDesign: Cross sectional study. Setting: Medical unit 1 at Combined Military Hospital Lahore, Pakistan. Duration: Six months (from 01-11-2007 to 30-4-2008). Subjects and Methods: Fifty adult patients with chronic diarrhea, irrespective of their gender were selected by nonprobability convenient sampling. Patients already diagnosed with diseases known to cause diarrhea and those with toxic mega colon wereexcluded from the study. All patients were subjected to fiberoptic colonoscopy and findings were recorded. Biopsies were taken fromsuspected lesions or from normal looking mucosa. Diagnosis was made with colonoscopic and histopathologic findings. Results: Thirty two(64%) patients had abnormal findings visible on colonoscopy. Histopathology was normal in 18 (36%). Twenty (40%) patients hadulcerative colitis, seventeen (34%) had IBS, five (10%) had CA colon and three (6%) patients had crohn’s disease. Other diagnosesincluded non specific colitis, tubulovillous adenoma and infection. Twenty three out of 24 patients (95%) who had blood in stools had avisible abnormality on colonoscopy whereas colonoscopy was positive in only 33% of patients who did not have blood in stools.Conclusion: Most causes of large gut chronic diarrhea can be identified by colonoscopy and biopsy. Colonoscopy has a very high yield inchronic diarrhea and should be recommended for its work up. Its yield is even higher in patients with bloody diarrhea.