Efficacy of antimicrobial therapy in patients with uncomplicated acute colonic diverticulitis: an updated systematic review and meta-analysis.

The need for antimicrobial therapy for uncomplicated acute diverticulitis of the colon remains controversial. We conducted a systematic review of the efficacy of antimicrobial agents against this disease, including new randomized controlled trials (RCTs) reported in recent years, and evaluated their efficacy using a meta-analytic approach. RCTs were searched using PubMed, EMBASE, Google Scholar, Cochrane Library, Ichushi-Web, and eight registries. Keywords were 'colonic diverticulitis', 'diverticulitis', 'antimicrobial agents', ''antibiotics, 'complication', 'abscess', 'gastrointestinal perforation', 'gastrointestinal obstruction', 'diverticular hemorrhage', and 'fistula'. Studies with antimicrobial treatment in the intervention group and placebo or no treatment in the control group were selected by multiple reviewers using uniform inclusion criteria, and data were extracted. Prevention of any complication was assessed as the primary outcome, and efficacy was expressed as risk ratio (RR) and risk difference (RD). A meta-analysis was performed using 5 RCTs of the 21 studies that were eligible for scrutiny in the initial search and which qualified for final inclusion. Three of these studies were not included in the previous meta-analysis. Subjects included 1039 in the intervention group and 1040 in the control group. Pooled RR = 0.86 (95% confidence interval, 0.58-1.28) and pooled RD = -0.01 (-0.03 to 0.01) for the effect of antimicrobial agents in reducing any complications. Recurrences, readmissions, and surgical interventions did not significantly show the efficacies of using antimicrobial agents. A meta-analysis of recently reported RCTs did not provide evidence that antimicrobial therapy improves clinical outcomes in uncomplicated acute diverticulitis of the colon.