Publications by authors named "L Massias"

The combination of aztreonam (ATM) and avibactam (AVI) is an attractive option to treat infections caused by extended spectrum β-lactamase plus NDM-1-producing . Since ATM activity was shown to be severely impacted by an increase in the inoculum size , we wondered whether ATM-AVI activity could be impaired in high-inoculum infections. We analyzed the impact of the inoculum size on ATM-AVI activity and in a murine model of peritonitis due to susceptible CFT073-pTOPO and its isogenic derivatives producing NDM-1 ( CFT073-NDM1) and CTX-M-15 plus NDM-1 ( CFT073-CTXM15-NDM1).

View Article and Find Full Text PDF

Cefiderocol (FDC) is a siderophore cephalosporin now recognized as a new weapon in the treatment of difficult-to-treat-resistant (DTR) Gram-negative pathogens, including carbapenemase-producing enterobacterales and non-fermentative Gram-negative bacilli (GNB). This article reports our experience with an FDC-based regimen in the treatment of 16 extremely severe patients (invasive mechanical ventilation, 15/16; extracorporeal membrane oxygenation, 9/16; and renal replacement therapy, 8/16) infected with DTR GNB. Our case series provides detailed insight into the pharmacokinetic profile and the microbiological data in real-life conditions.

View Article and Find Full Text PDF

Background: Optimal treatment of carbapenemase-producing Enterobacterales (CPE) bone infections is poorly defined. This study evaluated the efficacy of the novel beta-lactam-beta-lactamase inhibitor-ceftazidime-avibactam (CAZ-AVI)-with different antibiotic combinations in an experimental model of CPE osteomyelitis.

Methods: KPC-99YC is a clinical strain of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae with intermediate susceptibility to meropenem (MIC 4 mg/L), gentamicin (MIC 0.

View Article and Find Full Text PDF
Article Synopsis
  • There is a need for alternative treatments against NDM-1-producing E. coli, as existing antibiotics like colistin and fosfomycin often lead to resistant mutations when used alone.
  • In experiments with modified E. coli strains, the combination of colistin and fosfomycin showed effective in vitro and reduced mortality and bacterial loads in an animal model, although fosfomycin-resistant mutants still emerged in some cases.
  • Overall, while combining these two antibiotics is a promising option for treating NDM-1 E. coli infections, it does not completely prevent resistance in colistin-resistant strains.
View Article and Find Full Text PDF