Incidence of ESBLs and carbapenemases among Enterobacterales and carbapenemases in Pseudomonas aeruginosa isolates collected globally: results from ATLAS 2017–2019

OBJECTIVES: To assess the global and regional distribution of ESBLs in Enterobacterales and carbapenemases in Enterobacterales and Pseudomonas aeruginosa. METHODS: Antimicrobial susceptibility of isolates collected from ATLAS (2017–2019) was determined per CLSI guidelines. Enterobacterales exhibiting meropenem MICs ≥2 mg/L and/or ceftazidime/avibactam and/or aztreonam/avibactam MICs ≥16 mg/L, Escherichia coli and Klebsiella pneumoniae with aztreonam and/or ceftazidime MICs ≥2 mg/L, and P. aeruginosa with meropenem MICs ≥4 mg/L were screened for β-lactamases by PCR and sequencing. RESULTS: Globally, ESBL-positive E. coli (23.7%, 4750/20047) and K. pneumoniae (35.1%, 6055/17229) carried predominantly the CTX-M-15 variant (E. coli: 53.9%; K. pneumoniae: 80.0%) with highest incidence in Africa/Middle East (AfME). Among carbapenem-resistant (CR) E. coli (1.1%, 217/20047) and Enterobacter cloacae (3.8%, 259/6866), NDMs were predominant (E. coli in AfME: 62.5%; E. cloacae in Asia Pacific: 59.7%). CR K. pneumoniae (13.3%, 2299/17 229) and P. aeruginosa (20.3%, 4187/20 643) carried predominantly KPC (30.9%) and VIM (14.7%), respectively, with highest frequency in Latin America. Among ESBL-positive Enterobacterales, susceptibility to ceftazidime/avibactam (>90.0%) and amikacin (>85.0%) was higher than to piperacillin/tazobactam (>45.0%) and ciprofloxacin (>7.4%). In CR Enterobacterales, susceptibility to amikacin (>54.0%) and ceftazidime/avibactam (>31.0%) was higher than to ciprofloxacin (>2.7%) and piperacillin/tazobactam (>0.5%). CR P. aeruginosa similarly demonstrated higher susceptibility to amikacin (63.4%) and ceftazidime/avibactam (61.9%) than to ciprofloxacin (26.2%) and piperacillin/tazobactam (25.3%). CONCLUSIONS: Varied distribution of resistance genotypes across regions among ESBL-positive Enterobacterales and CR Enterobacterales and P. aeruginosa provide crucial insights on major resistance mechanisms and trends observed in recent years. Continued surveillance is warranted for monitoring global dissemination and resistance.