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Published on: September 9, 2015
German Multicenter Study Analyzing Antimicrobial Activity of Ceftazidime-Avibactam of Clinical Meropenem-Resistant
Jana Manzke1, Raphael Stauf1, Bernd Neumann1
1Institute of Clinical Hygiene, Medical Microbiology and Infectiology, Paracelsus Medical University, Klinikum Nürnberg, 90419 Nuremberg, Germany.
Abstract:
Multidrug resistance is an emerging healthcare issue, especially concerning Pseudomonas aeruginosa. In this multicenter study, P. aeruginosa isolates with resistance against meropenem detected by routine methods were collected and tested for carbapenemase production and susceptibility against ceftazidime-avibactam. Meropenem-resistant isolates of P. aeruginosa from various clinical materials were collected at 11 tertiary care hospitals in Germany from 2017−2019. Minimum inhibitory concentrations (MICs) were determined via microdilution plates (MICRONAUT-S) of ceftazidime-avibactam and meropenem at each center. Detection of the presence of carbapenemases was performed by PCR or immunochromatography. For meropenem-resistant isolates (n = 448), the MIC range of ceftazidime-avibactam was 0.25−128 mg/L, MIC90 was 128 mg/L and MIC50 was 16 mg/L. According to EUCAST clinical breakpoints, 213 of all meropenem-resistant P. aeruginosa isolates were categorized as susceptible (47.5%) to ceftazidime-avibactam. Metallo-β-lactamases (MBL) could be detected in 122 isolates (27.3%). The MIC range of ceftazidime-avibactam in MBL-positive isolates was 4−128 mg/L, MIC90 was >128 mg/L and MIC50 was 32 mg/L. There was strong variation in the prevalence of MBL-positive isolates among centers. Our in vitro results support ceftazidime-avibactam as a treatment option against infections caused by meropenem-resistant, MBL-negative P. aeruginosa.
Insights
Ceftazidime-avibactam shows promise against meropenem-resistant Pseudomonas aeruginosa, particularly in isolates lacking metallo-β-lactamases (MBL). This study evaluated its efficacy in a multicenter German study.
Area of Science:
- Clinical microbiology
- Infectious diseases
- Antimicrobial resistance
Background:
- Multidrug resistance in Pseudomonas aeruginosa is a growing global health concern.
- Meropenem resistance in P. aeruginosa necessitates alternative treatment strategies.
Purpose of the Study:
- To assess the in vitro activity of ceftazidime-avibactam against meropenem-resistant Pseudomonas aeruginosa isolates.
- To determine the prevalence of carbapenemase production, specifically metallo-β-lactamases (MBL), in these resistant isolates.
Main Methods:
- A multicenter study collected 448 meropenem-resistant P. aeruginosa isolates from 11 German hospitals (2017-2019).
- Minimum inhibitory concentrations (MICs) for ceftazidime-avibactam and meropenem were determined using microdilution.
- Carbapenemase presence was identified via PCR or immunochromatography.
Main Results:
- 47.5% (213/448) of meropenem-resistant isolates were susceptible to ceftazidime-avibactam (MIC50=16 mg/L, MIC90=128 mg/L).
- Metallo-β-lactamases (MBL) were detected in 27.3% (122/448) of isolates.
- Ceftazidime-avibactam demonstrated significant activity against MBL-negative meropenem-resistant P. aeruginosa.
Conclusions:
- Ceftazidime-avibactam is a potential therapeutic option for infections caused by meropenem-resistant P. aeruginosa, especially when MBLs are absent.
- The study highlights the variability in MBL prevalence across different clinical centers.
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