Ceftazidime-avibactam and comparators against Pseudomonas aeruginosa isolates collected globally and in each geographical region between 2017–2020

Abstract

The objective of this study was to assess the distribution and antimicrobial susceptibility of P.aeruginosa isolates against ceftazidime-avibactam (CAZ-AVI) and a panel of comparator agents collected globally and in each region from 2017-2020 from the Antimicrobial Testing Leadership and Surveillance (ATLAS) program. Susceptibility and minimum inhibitory concentration (MIC) of all P. aeruginosa isolates were determined using broth microdilution methodology for according to the Clinical and Laboratory Standards Institute guidelines. Of the total 29,746 isolates of P. aeruginosa collected, 20.9% were multidrug resistant (MDR), 20.7% were extremely drug resistant (XDR), 8.4% were CAZ-AVI-resistant (CAZ-AVI-R), and 3.0% were MBL-positive. Amongst the MBL-positive isolates, the proportion of VIM-positive isolates was highest (77.8%). The highest proportion of MDR (25.5%), XDR (25.0%), MBL (5.7%), and CAZ-AVI-R (12.3%) isolates were in Latin America. Amongst the sources, the highest proportion of isolates were from respiratory sources (43.0%) and the majority of isolates were from non-ICU wards (71.2%). Overall, CAZ-AVI showed high susceptibility to all P. aeruginosa isolates (90.9%). However, MDR and XDR isolates were less susceptible to CAZ-AVI (≤60.7). Amongst the comparators, only colistin (99.1%) and amikacin (90.5%) showed good overall susceptibility to all isolates of P. aeruginosa. However, only colistin was active (≥98.3%) against all the resistant isolates. CAZ-AVI presents a potential treatment option against P. aeruginosa infections. However, active monitoring and surveillance, especially of the resistant phenotypes is warranted for effective treatment of infections caused by P. aeruginosa.