The role of colonoscopy and CT colonography in patients presenting with symptoms of constipation

OBJECTIVE

There is controversy whether constipation as a primary presenting complaint is an indication for diagnostic colonoscopy. CT colonography (CTC) is a less invasive and more acceptable alternative. We compared the completion and sensitivity of colonoscopy with CTC in patients who presented with the primary symptom of constipation.

METHODS

A retrospective study was conducted which examined the first 100 colonoscopies and 100 CTCs carried out for the primary symptom of constipation from June 2012 to December 2013. The primary outcome measure was failure rate of the investigations. Secondary outcomes included reasons for failure and comparison of cost effectiveness between the two modalities.

RESULTS

A total of 200 patients were included in this study. Of these, the first consecutive 100 colonoscopies and 100 CTCs were included. One colonic cancer was detected in each of the CTC and the colonoscopy arm, respectively. 37 (37%) attempted colonoscopies were incomplete examinations. The most common reasons were discomfort (51.4%) and poor bowel preparation (27%). There was no failure of CTC. For 100 patients, CTC as a primary investigation was a more cost-effective investigation (p ≤ 0.01) costing £55,016 as compared with colonoscopy costing £73,666.

CONCLUSION

There is an unacceptably high failure rate of colonoscopy in patients who presented with the primary symptom of constipation. Hence, we propose that CTC may be an acceptable first-line investigation with a further colonoscopy/flexible sigmoidoscopy if lesions are detected. Advances in knowledge: First study to examine the use of CTC in patients with constipation.