Evaluation of ceftolozane-tazobactam susceptibility on a French nationwide collection of Enterobacterales

•88% of Enterobacteralesresistant to 3rdgeneration cephalosporins (3GC) remained susceptible to ceftolozane-tazobactam•Among ESBL producers, susceptibility to ceftolozane-tazobactam varies from 93% to only 13% for CTX-M and SHV-ESBL producers, respectively•In France, 95.6% of enterobacterial isolates responsible for infections (except urinary tract infections) collected prospectively were susceptible to ceftolozane-tazobactam•Etest® led to an underestimation of the ceftolozane-tazobactam MIC compared to a commercial broth microdilution method used as reference but the categorization agreement remained high (99%).