Diagnostic value of terminal ileum intubation during colonoscopy

Since the diagnostic value of ileoscopy is not well documented, it is uncertain if terminal ileum intubation should be performed routinely in patients undergoing colonoscopy. We aimed to assess the diagnostic yield of terminal ileum intubation during colonoscopy according to indications for colonoscopy.

We routinely performed terminal ileum intubation in subjects who underwent colonoscopy at Ajou University Hospital between 1 January 2005 and 31 December 2005. Demographic data, indications for colonoscopy, endoscopic, and histopathologic findings of the terminal ileum were assessed.

A total of 3921 subjects underwent colonoscopy. The terminal ileum was successfully intubated in 3417 cases (87.1%). Macroscopic abnormality on terminal ileum was present in 125 cases (3.7%), and biopsies were taken for all of them. Clinically significant histopathology was observed in 11 cases, giving a 0.3% diagnostic yield in all ileoscopies. Seven out of 11 cases were diagnosed as Crohn's disease. The rate of diagnostic yield was 1.8% in patients with right lower quadrant (RLQ) abdominal pain and 0.4% in patients with diarrhea. This rate in cases with RLQ pain was significantly greater compared with the indications for medical check-ups.

Terminal ileum intubation during colonoscopy identifies significant pathology in 1.8% of cases who have RLQ abdominal pain, suggesting diagnostic value in this setting. However, its diagnostic yield is very low in other indications for colonoscopy. Thus the decision to perform ileoscopy or not during colonoscopy needs to be made on a case-by-case basis.