Should a colonoscopy be offered routinely to patients with CT proven acute diverticulitis? A retrospective cohort study and meta-analysis of best available evidence

BACKGROUND: The current guidelines suggest that patients should undergo endoscopic evaluation of the colonic lumen after an episode of computed tomography (CT) proven acute diverticulitis to rule out malignancy. The usefulness of routine endoscopic evaluation of CT proven diverticulitis remains unknown. AIM: To establish whether routine colonoscopy should be offered to patients after an episode of diverticulitis. METHODS: We performed a retrospective study, comparing two groups: a diverticulitis group and a control group. The diverticulitis group consisted of patients undergoing a colonoscopy after an episode of diverticulitis. The control group consisted of asymptomatic patients undergoing a screening sigmoidoscopy. We also performed a systematic review and meta-analysis. We searched electronic data resources to identify all relevant studies. The primary outcome was the number of adenomas found, while the secondary outcomes were the number of cancers and polyps identified, and the adenoma risk. RESULTS: 68 and 1309 patients were included in the diverticulitis and control groups respectively. There was no difference in the risk of adenomas (5.9% vs 7.6%, P = 0.59), non-advanced adenomas (5.9% vs 6.9%, P = 0.75), advanced adenomas (0% vs 0.8%, P = 1), cancer (0% vs 0.15%, P = 1.00), and polyps (16.2% vs 14.2%, P = 0.65) between both groups. Meta-analysis of data from 4 retrospective observational studies, enrolling 4459 patients, showed no difference between the groups in terms of risk of adenomas (RD = -0.05, 95%CI: -0.11, 0.01, P = 0.10), non-advanced adenomas (RD = -0.02, 95%CI: -0.08, 0.04, P = 0.44), advanced adenomas (RD = -0.01, 95%CI: -0.04, 0.02, P = 0.36), cancer (RD = 0.01, 95%CI: -0.01, 0.03, P = 0.32), and polyps (RD = -0.05, 95%CI: -0.12, 0.02, P = 0.18). CONCLUSION: Routine colonoscopy may not be appropriate in patients with acute diverticulitis. High quality prospective studies are required for more robust conclusions.