Susceptibility Trends Of Ceftolozane/Tazobactam And Comparators When Tested Against Us Gram-Negative Bacterial Surveillance Isolates (2012?2018)

Ceftolozane/tazobactam is an antipseudomonal cephalosporin combined with a,B-lactamase inhibitor. Ceftolozane/tazobactam has been approved in >60 countries for treating complicated urinary tract infections, acute pyelonephritis, complicated intra-abdominal infections (with metronidazole), and hospital-acquired pneumonia, including ventilator-associated pneumonia in adults. We analyzed susceptibilities for 35,882 gram-negative isolates collected from patients in 35 US medical centers from 2012 to 2018. The rate of multi-drug resistant Enterobacterales was stable (9.5%?10.1%), while the P. aeruginosa multi-drug resistance rate increased from 15.5% in 2012 to 22.9% in 2018. The carbapenem-resistant Enterobacterales rates varied from 0.9% to 2.2% and extended-spectrum ,B-lactamase phenotypes increased from 10.5% to 16.8%. The most active drugs against P. aeruginosa were ceftolozane/tazobactam (95.8%?97.5% susceptible) and amikacin (93.9%?98.0%); against Enterobacterales, amikacin (97.9%?98.8%), meropenem (97.7%?98.8%), and ceftolozane/tazobactam (93.3%?95.6%) were the most active. These data suggest that ceftolozane/tazobactam has effective in vitro activity against organisms causing serious gram-negative infections.? 2021 Elsevier Inc. All rights reserved.