Is routine colonoscopy necessary for patients who have an unequivocal computerised tomography diagnosis of acute...

To assess the incidence of underlying colorectal malignancy in patients admitted as an emergency with a CT diagnosis of acute diverticulitis and determine the need for routine follow up colonoscopy.

A retrospective study was performed on all patients who had been admitted to our surgical unit with CT diagnosed diverticulitis from September 2016 to September 2018 (n = 125).

11 patients (8.8%) required emergency resection with no underlying malignancy found. 76 patients (61%) had a follow up colonoscopy after being discharged. 4 patients were found to have an underlying colorectal malignancy, one of them suspected on CT and another an incidentally detected caecal polyp cancer. Therefore 3/87(3.4%) had an unexpected cancer diagnosis and all those in the diseased segment were within complicated diverticulitis.

Nowadays, multi-slice CT scanners are so good at giving an accurate assessment of colonic pathology. In our study, 96.6% of the patients with a CT diagnosis of acute diverticulitis had no underlying malignancy in the diseased segment with all the cancers within complicated diverticulitis. With such a low yield of underlying malignancy in uncomplicated diverticulitis, we question the need for routine follow up colonoscopy when there is no CT suspicion of malignancy in these patients.