In Vitro-In Vivo Discordance with Humanized Piperacillin-Tazobactam Exposures against Piperacillin-Tazobactam- Resistant/Pan-beta-Lactam-Susceptible Klebsiella pneumoniae Strains

摘要

Recent findings have identified Klebsiella pneumoniae strains that are pan-beta-lactam susceptible (PBL-S) but piperacillin-tazobactam resistant (TZP-R) in vitro. We assessed the efficacy of a humanized exposure of piperacillin-tazobactam (TZP) against 12 TZP-R/PBL-S K. pneumoniae isolates in an immunocompromised murine lung infection model. Discordance between the in vitro resistance profile and the in vivo efficacy of human-simulated TZP exposures against this phenotypic profile was observed. Additional studies are required to define the clinical implications of these TZP-R/PBL-S strains.