2026-04-17T16:04:39Zhttps://recercat.cat/oai/request

oai:recercat.cat:2072/4713282024-11-04T06:40:39Zcom_2072_98col_2072_378192

00925njm 22002777a 4500 dc Montero, María M. author Domene-Ochoa, Sandra author López-Causapé, Carla author Luque, Sonia author Sorlí, Luisa author Campillo, Núria author Padilla León, Eduardo author Prim, Núria author Ferrer-Alapont, Lorena author Angulo-Brunet, Ariadna author Grau, Santiago author Oliver, Antonio author Horcajada, Juan Pablo author Universitat Autònoma de Barcelona author 2021 Ceftolozane/tazobactam (C/T) has emerged as a potential agent for the treatment of extensively drug-resistant (XDR) Pseudomonas aeruginosa infections. As it is a time-dependent antimicrobial, prolonged infusion may help achieve pharmacokinetic/pharmacodynamic (PK/PD) targets. To compare alternative steady-state concentrations (Css) of C/T in continuous infusion (CI) against three XDR P. aeruginosa ST175 isolates with C/T minimum inhibitory concentration (MIC) values of 2 to 16 mg/L in a hollow-fiber infection model (HFIM). Duplicate 10-day HFIM assays were performed to evaluate Css of C/T in CI: one compared 20 and 45 mg/L against the C/T-susceptible isolate while the other compared 45 and 80 mg/L against the two C/T-non-susceptible isolates. C/T resistance emerged when C/T-susceptible isolate was treated with C/T in CI at a Css of 20 mg/L; which showed a deletion in the gene encoding AmpC β-lactamase. The higher dosing regimen (80 mg/L) showed a slight advantage in effectiveness. The higher dosing regimen has the greatest bactericidal effect, regardless of C/T MIC. Exposure to the suboptimal Css of 20 mg/L led to the emergence of C/T resistance in the susceptible isolate. Antimicrobial regimens should be optimized through C/T levels monitoring and dose adjustments to improve clinical management. http://hdl.handle.net/2072/471328 Antimicrobials Bacteria Impact of ceftolozane/tazobactam concentrations in continuous infusion against extensively drug-resistant Pseudomonas aeruginosa isolates in a hollow-fiber infection model