Abstract
BACKGROUND: This study reports the global trends of antimicrobial susceptibility to ceftaroline and ceftazidime-avibactam using data from the Antimicrobial Testing Leadership and Surveillance (ATLAS) program between 2012 and 2016. METHODS: For the 2012-2016 ATLAS program, 205 medical centers located in Africa-Middle East (n = 12), Asia-Pacific (n = 32), Europe (n = 94), Latin America (n = 26), North America (n = 31), and Oceania (n = 10) consecutively collected the clinical isolates. The minimum inhibitory concentrations (MICs) and in vitro susceptibilities to ceftaroline and ceftazidime-avibactam were assessed using the Clinical and Laboratory Standards Institute (CLSI) 2019and European Committee on Antimicrobial Susceptibility Testing (EUCAST) 2019 guidelines. RESULTS: Between 2012 and 2016, 176,345 isolates were collected from around the globe and included in the analysis. Regarding Gram-negative bacteria, ceftazidime-avibactam demonstrated high susceptibility (> 90%) against Enterobacteriaceae and Pseudomonas aeruginosa, with increased antimicrobial activity observed from the addition of avibactam (4 mg/L) to ceftazidime. Regarding Gram-positive bacteria, ceftaroline showed > 90% susceptibility against Staphylococcus aureus, Streptococcus pneumoniae, α-and β-hemolytic Streptococcus. The antimicrobial susceptibilities to ceftaroline and ceftazidime-avibactam were mostly stable from 2012 to 2016, but the susceptibilities to ceftazidime-avibactam to carbapenem-resistant (CR) Klebsiella pneumonia (88.4-81.6%) and to CR-P. aeruginosa (89.6-72.7%) decreased over time. In terms of regional difference, the susceptibilities of methicillin-resistant S. aureus to ceftaroline in Asia and of CR-K. pneumonia to ceftazidime-avibactam in Asia/Africa-Middle East were lower compared with other regions, while the susceptibility of CR-P. aeruginosa to ceftazidime-avibactam in North America was higher. CONCLUSION: The addition of avibactam improves the activity of ceftazidime against Enterobacteriaceae and P. aeruginosa. The global antimicrobial susceptibilities to ceftaroline and ceftazidime-avibactam were, in general, stable from 2012 to 2016, but a marked reduction in the susceptibilities of specific species and CR-P. aeruginosa to ceftazidime-avibactam was observed.