A Systematic Review of Pericolic Extraluminal Air in Left-Sided Acute Colonic Diverticulitis

BACKGROUND: Although approximately 15% of all patients with acute colonic diverticulitis have pericolic extraluminal air found on computed tomography (CT), studies on the natural course and treatment of these patients are scarce. It is not clear whether these patients behave as mild uncomplicated diverticulitis or as severe diverticulitis needing more aggressive treatment. Consequently, there is no consensus about the treatment, guidelines do not discuss this group of patients, and physicians treat these patients based on their own experiences and opinion. An evidence-based approach is needed to prevent overtreatment or undertreatment in patients with pericolic extraluminal air. METHODS: PubMed and EMBASE databases were searched for all studies reporting clinical outcomes of the initial diverticulitis episode of CT-proven left-sided colonic diverticulitis. Primary outcome measures were the need for emergency surgery and percutaneous abscess drainage. RESULTS: A total of eight studies with 251 patients with pericolic extraluminal air were included. Rates of emergency surgery in isolated patients with pericolic extraluminal air were reported in six studies, yielding a pooled rate of 6% (95% confidence interval CI 3%-12%). In three studies reporting a combined total of only 56 patients, no patient underwent percutaneous abscess drainage. The long-term (6 mo) need for surgery was 38% in one study, although reasons for surgery were lacking. CONCLUSION: An initial 94% success rate of non-operative treatment in left-sided colonic diverticulitis patients with pericolic extraluminal air seems to justify a conservative approach including antibiotic agents. Low-quality evidence indicates the need for surgery in up to 38% in the medium-long term.