Meta-analysis of the role of colonoscopy after an episode of left-sided acute diverticulitis

Abstract

Background Routine colonoscopy was traditionally recommended after acute diverticulitis to exclude coexistent malignancy. Improved CT imaging may make routine colonoscopy less required over time but most guidelines still recommend it. The aim of this review was to assess the role of colonoscopy in patients with CT‐proven acute diverticulitis. Methods PubMed and Embase were searched for studies reporting the prevalence of advanced colorectal neoplasia (ACN) or colorectal carcinoma in patients who underwent colonoscopy within 1 year after CT‐proven left‐sided acute diverticulitis. The prevalence was pooled using a random‐effects model and, if possible, compared with that among asymptomatic controls. Results Seventeen studies with 3296 patients were included. The pooled prevalence of ACN was 6·9 (95 per cent c.i. 5·0 to 9·4) per cent and that of colorectal carcinoma was 2·1 (1·5 to 3·1) per cent. Only two studies reported a comparison with asymptomatic controls, showing comparable risks (risk ratio 1·80, 95 per cent c.i. 0·66 to 4·96). In subgroup analysis of patients with uncomplicated acute diverticulitis, the prevalence of colorectal carcinoma was only 0·5 (0·2 to 1·2) per cent. Conclusion Routine colonoscopy may be omitted in patients with uncomplicated diverticulitis if CT imaging is otherwise clear. Patients with complicated disease or ongoing symptoms should undergo colonoscopy.

European Society of Coloproctology: guidelines for the management of diverticular disease of the colon

“…Many primarily retrospective studies have investigated detection rates for CRC with colonoscopy after acute diverticulitis (Data S1, 1.5). However, meta-analyses of data have been troubled by the heterogeneity of the studies, the lack of a valid reference population, inconsistent reporting of CT verification of the diverticulitis episode, inconsistent definitions of uncomplicated and complicated diverticulitis and the lack of information about ongoing symptoms in the included patients [53][54][55][56][57]. Routine colonoscopy after an episode of conservatively treated complicated diverticulitis is generally accepted, as the prevalence of CRC is between 7.9% and 10.8% in this group [53,55,56].…”

“…For patients with CT verified uncomplicated diverticulitis, the two most recent meta-analyses have calculated a prevalence of CRC of 0.5% and 1.2% respectively due to the inclusion of different studies [55,56]. Furthermore, in the meta-analyses different reference populations are used leading to different conclusions.…”

“…Screening probably overestimates the prevalence of CRC in asymptomatic patients, as participation rates are usually far below 50% and symptomatic and high-risk patients probably are more likely to attend. Also, incidence rates for CRC have been used to estimate the prevalence of undiagnosed CRC in the population [55,61], which has the weakness that it is uncertain how long the CRC existed before diagnosis.…”

Author response to Comment on: Meta-analysis of the role of colonoscopy after an episode of left-sided acute diverticulitis

“…We found a 0·5 (95 per cent c.i. 0·2 to 1·2) per cent prevalence in patients with CT‐proven, left‐sided and uncomplicated (Hinchey 1a) diverticulitis who underwent colonoscopy. The meta‐analysis of Meyer et al .…”

This month on Twitter

“…In response to the meta‐analysis by Rottier et al . on the role of colonoscopy after an episode of left‐sided acute diverticulitis, @juliomayol tweeted a poll in which 56 per cent of respondents said they scope selectively in this situation. Richard Brady (@researchactive) called Larsen et al .…”