Hinchey Ia acute diverticulitis with isolated pericolic air on CT imaging; to operate or not? A systematic review

BACKGROUND: Colonic diverticulitis is one of the most common gastrointestinal pathologies and its prevalence increases with the aging of the population in Western countries. Approximately 15% of patients with Hinchey Ia acute diverticulitis present with concomitant isolated pericolic air bubbles that denote intestinal perforation and thus prompting a more "aggressive" treatment attitude, including emergency surgery, despite the absence of evidence-based indications. This study is trying to delineate whether this approach is justified or whether a conservative treatment would suffice for this group of patients. MATERIALS AND METHODS: PubMed and Cochrane CENTRAL databases were systematically searched in order to identify all studies that reported the need for emergency surgery and for percutaneous drainage in patients presenting with Hinchey Ia colonic diverticulitis with extraluminal pericolic gas on CT imaging who were initially treated conservatively. The last database search was performed on November 29, 2019 and no language or study type restriction criteria were applied. The Newcastle-Ottawa scale was used to assess the risk of bias of selected studies. RESULTS: Nine observational cohort studies with 411 patients reported the need for emergency surgery, with a pooled rate of 5.1%. Among these studies, four studies comprising 165 patients reported the need for percutaneous drainage separately with a pooled rate of 1.2%. CONCLUSION: Non-operative management of Hinchey Ia acute diverticulitis with isolated pericolic air is feasible and safe with a success rate of 94.9%. Abscess formation requiring percutaneous drainage is present in only 1.2% of patients, thus rendering the conservative initial treatment of these patients justified. Nevertheless, low quality of included studies indicates further research to validate the outcomes of this review.