CT diagnosed acute diverticulitis: is the cost for subsequent colonoscopy to exclude associated carcinoma justified?

Aim: The role of large bowel investigations to exclude colorectal carcinoma after CT-confirmed acute diverticulitis remains unclear. A recent systematic review reported the lack of data to support routine colonoscopy in this cohort of patients.
Method: Patients with a discharge diagnosis of diverticulosis (ICD K57) were retrospectively identified by review of hospital records between August 2011 and January 2010. The radiology records were then searched to identify patients who had CT-confirmed acute diverticulitis.Subsequent colonoscopy, radiology and pathology records were reviewed to identify patients with colorectal polyps and carcinoma.
Results: One thousand patients’ records were reviewed, and 94 patients had CT-confirmed acute diverticulitis. There were 49 males and 45 females with mean age of 61 (range 19–92). Forty-four(46.8%) patients had subsequent follow-up colonoscopy. Ten (22.7%) colonoscopies successfully reached the caecum. The remainder of colonoscopies were limited by difficult sigmoid colon intubation. Hyperplastic polyps, low-grade adenomas and carcinomas were detected in 4 (9%), 4 (9%),0 (0%) patients respectively.
Conclusion: This study showed that follow-up colonoscopy had low diagnostic yield for malignan tpolyps in the presence of a confident diagnosis of acute diverticulitis on CT. These findings will have important implications for rationalisation of resources for this cohort of patients