The Utility of Routine Interval Colonoscopy after an Episode of Acute Diverticulitis

A BSTRACT Introduction: The incidence of diverticulitis is rising, and increasingly younger patients are affected. It is not always possible to exclude an underlying malignancy even on contrast enhanced CT. Therefore, there is a role for interval colonoscopy, however, guidelines about the optimal strategy for this are conflicting. We set out to explore the utility of routine interval colonoscopy in patients with diverticulitis. Methods: A single-centre retrospective study between 2018-2023 of all patients with CT-proven diverticulitis who underwent interval colonoscopy was undertaken. The primary outcome was the incidence of colorectal cancer. Secondary outcomes were the incidence of advanced adenomas and discordance between the location of pathology on CT and colonoscopy. Results: 123 patients were included. Most had sigmoid diverticulitis (66.7%) and Hinchey 1a disease (83.7%). Based on CT scans It was not possible to exclude an underlying malignancy in 21 cases. Most patients had a normal colonoscopy (82%) and no patients had colorectal cancer. One patient had an advanced adenoma and there was significant discordance in the location of pathology between CT and colonoscopy in four patients. Colonoscopy was affected by pain, suboptimal bowel preparation and difficulties traversing fixed segments of bowel. The total cost of colonoscopy was £140,466. Conclusion: An association between diverticulitis and malignancy has not been demonstrated. In patients with uncomplicated diverticulitis who have few risk factors for cancer there is minimal benefit from routine interval colonoscopy. A patient tailored approach should be taken – this would reduce the burden on waiting lists and finances. Further follow-up trials are necessary to establish evidence-based guidelines.