Fluoroquinolones versus beta lactams for complicated intra-abdominal infections: a meta-analysis of RCTs

Author(s):
Michail Mavros; Nikoletta Theochari; Konstantinos Economopoulos; Jack Sava

Background:

Intra-abdominal infections requiring surgical or percutaneous intervention are common and confer significant morbidity, mortality, and cost. In addition to source control, appropriate broad-spectrum antibiotic coverage is essential. According to the 2017 Surgical Infection Society guidelines, empiric coverage should be based on either a beta lactam-based or a fluoroquinolone-based regimen.

Hypothesis:

Fluoroquinolone-based regimens are as effective as beta lactam-based regimens for the treatment of patients with complicated intra-abdominal infections (cIAIs).

Methods:

A systematic review and meta-analysis of randomized controlled trials was performed using the PRISMA guidelines. We assessed trials comparing a fluoroquinolone-based regimen to a beta lactam-based regimen as an adjunct to operative or percutaneous intervention. Primary outcomes were effectiveness in the clinically evaluable (CE) population and mortality, and secondary outcomes were effectiveness in the intention-to-treat (ITT) and microbiologically evaluable (ME) population and safety. Subgroup analyses were performed based on the specific antimicrobials, the type of infection, the isolated pathogens, and the trial quality. Calculation of pooled risk ratios (RR) and 95% confidence intervals (CI) was performed using the DerSimonian-Laird random-effects model.

Results:

A total of 632 studies were identified, of which 9 (5090 patients) were included in the meta-analysis. Fluoroquinolone-based regimes included moxifloxacin (4 studies), ciprofloxacin/metronidazole (3 studies), and alartrofloxacin or clinafloxacin (1 study each). Beta lactam-based regimens included carbapenems (4 studies), ceftriaxone/metronidazole (3 studies), or piperacillin/tazobactam (2 studies). Duration of antimicrobials ranged from 5 to 14 days. Overall, there was no difference in effectiveness in the CE [risk ratio (RR) 0.99, 95% CI 0.96–1.03)], ITT (RR 0.98 [0.95–1.02]) or ME population (RR 0.98 [0.95-1.01]); mortality (RR 1.06 [0.79–1.42]), and safety profile (related adverse events RR 1.03 [0.77–1.37]) were also similar. On subset analysis, moxifloxacin was less effective than beta lactams in the CE (RR 0.96 [0.93–0.99]), ITT, and ME population (figure 1).

Conclusions:

Although overall fluoroquinolone-based and beta lactam-based regimens appear equally effective and safe for the treatment of patients with complicated intra-abdominal infections, limited data suggests inferior results with moxifloxacin. Selection of empiric coverage at individual institutions should be based on local bacterial epidemiology and patterns of resistance, as well as stewardship protocols.