Effect of aminoglycoside and beta-lactam combination therapy versus beta-lactam monotherapy on the emergence of antimicrobial resistance: a meta-analysis of randomized, controlled trials.
BACKGROUND
The addition of an aminoglycoside to a beta -lactam therapy regimen has been suggested to have a beneficial effect in delaying or preventing the development of antimicrobial resistance. We studied the effect of aminoglycoside/ beta -lactam combination therapy versus beta-lactam monotherapy on the emergence of resistance.


METHODS
We performed a meta-analysis of randomized, controlled trials (RCTs) that compared aminoglycoside/ beta-lactam combination therapy with beta-lactam monotherapy and that reported data regarding the emergence of resistance (primary outcome) and/or development of superinfection, treatment failure, treatment failure attributable to emergence of resistance, treatment failure attributable to superinfection, all-cause mortality during treatment, and mortality due to infection. Data for this meta-analysis were identified from the PubMed database, Current Contents database, Cochrane central register of controlled trials, and references in relevant articles.


RESULTS
A total of 8 RCTs were included in the analysis. Beta -lactam monotherapy was not associated with a greater emergence of resistance than was the aminoglycoside/ beta-lactam combination (odds ratio [OR], 0.90; 95% confidence interval [CI], 0.56-1.47). Actually, beta -lactam monotherapy was associated with fewer superinfections (OR, 0.62; 95% CI, 0.42-0.93) and fewer treatment failures (OR, 0.62; 95% CI, 0.38-1.01). Rates of treatment failure attributable to emergence of resistance (OR, 3.09; 95% CI, 0.75-12.82), treatment failure attributable to superinfection (OR, 0.60; 95% CI, 0.33-1.10), all-cause mortality during treatment (OR, 0.70; 95% CI, 0.40-1.25), and mortality due to infection (OR, 0.74; 95% CI, 0.46-1.21) did not differ significantly between the 2 regimens.


CONCLUSIONS
Compared with beta-lactam monotherapy, the aminoglycoside/ beta-lactam combination was not associated with a beneficial effect on the development of antimicrobial resistance among initially antimicrobial-susceptible isolates.
Bliziotis
Ioannis A
IA
Alfa Institute of Biomedical Sciences, Henry Dunant Hospital, Athens, Greece.
Samonis
George
G
Vardakas
Konstantinos Z
KZ
Chrysanthopoulou
Stavroula
S
Falagas
Matthew E
ME
D000617:Aminoglycosides / Q000008:administration & dosage / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D001424:Bacterial Infections / Q000188:drug therapy / Q000401:mortality; D024881:Drug Resistance, Bacterial; D004359:Drug Therapy, Combination; D006801:Humans; D016017:Odds Ratio; D016032:Randomized Controlled Trials as Topic; D015163:Superinfection; D017211:Treatment Failure; D047090:beta-Lactams / Q000008:administration & dosage / Q000494:pharmacology*
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D047090:beta-Lactams