Impact of an Antimicrobial Stewardship Program on the Incidence of Carbapenem Resistant Gram-Negative Bacilli: An Interrupted Time-Series Analysis.

Carbapenem-resistant Gram-negative bacilli (CR-GNB) are a critical public health threat, and carbapenem use contributes to their spread. Antimicrobial stewardship programs (ASPs) have proven successful in reducing antimicrobial use. However, evidence on the impact of carbapenem resistance remains unclear. We evaluated the impact of a multifaceted ASP on carbapenem use and incidence of CR-GNB in a high-endemic hospital. An interrupted time-series analysis was conducted one year before and two years after starting the ASP to assess carbapenem consumption, CR-GNB incidence, death rates of sentinel events, and other variables potentially related to CR-GNB incidence. An intense reduction in carbapenem consumption occurred after starting the intervention and was sustained two years later (relative effect -83.51%; 95% CI -87.23 to -79.79). The incidence density of CR-GNB decreased by -0.915 cases per 1000 occupied bed days (95% CI -1.743 to -0.087). This effect was especially marked in CR-Klebsiella pneumoniae and CR-Escherichia coli, reversing the pre-intervention upward trend and leading to a relative reduction of -91.15% (95% CI -105.53 to -76.76) and -89.93% (95% CI -107.03 to -72.83), respectively, two years after starting the program. Death rates did not change. This ASP contributed to decreasing CR-GNB incidence through a sustained reduction in antibiotic use without increasing mortality rates.

Impact of the PROVAUR stewardship programme on linezolid resistance in a tertiary university hospital: a before-and-after interventional study.

BACKGROUND: There is little evidence of the impact of antimicrobial stewardship programmes on antimicrobial resistance. OBJECTIVES: To study the efficacy and safety of a package of educational and interventional measures to optimize linezolid use and its impact on bacterial resistance. METHODS: A quasi-experimental study was designed and carried out before and after implementation of a stewardship programme in hospitalized patients with Gram-positive infections treated with linezolid. RESULTS: The intervention reduced linezolid consumption by 76%. The risk of linezolid-resistant CoNS isolates (OR = 0.37; 95% CI = 0.27-0.49; P < 0.001) and Enterococcus faecalis (OR = 0.44; 95% CI = 0.21-0.90; P = 0.03) during the intervention period was lower than in the pre-intervention period. CONCLUSIONS: A programme to optimize linezolid use can contribute to reducing the resistance rate of CoNS and E. faecalis to this antibiotic.