Interval colonoscopy following acute diverticulitis should not be discouraged yet: results from a retrospective cohort.

BACKGROUND Although included in some guidelines, the recommendation of interval colonoscopy after an acute diverticulitis (AD) episode has recently been questioned. In this study, we evaluated the incidence of colon cancer during the follow-up of an episode of AD. METHODS A retrospective review was carried out of patients with conservatively treated AD at our Institution (January 2011 to December 2018) with or without endoscopic study. Patients who had no colonoscopy performed were followed for two years. The demographic, clinical, radiological, follow-up and anatomopathological records were analysed. We determined CT scan validity for the differential diagnosis of CC and AD; sensibility, specificity, predictive values and likelihood ratios were calculated. Patients lost to follow-up and patients who had had colonoscopy in the previous three years were excluded. RESULTS This study included 285 patients with a mean age of 59 years. A total of 225 interval colonoscopies were performed and 60 patients without colonoscopy were followed up. There were 19 CC (6.7%) diagnosed, 14 with interval colonoscopy and 5 during follow-up; 8 (42.1%) happened in patients who had had an episode of uncomplicated AD. Although CT scan accuracy is high, 87.7%, positive and negative likelihood ratios were low, 4.67 and 0.64, respectively. CONCLUSIONS Interval colonoscopy should still be advisable after an episode of AD. The rationale for this statement is based on a non-negligible rate of hidden CC and an important uncertainty in the differential diagnosis.