avibactam and Sepsis

To assess the impact of carbapenem resistance on mortality in Klebsiella pneumoniae bloodstream infection (BSI) in the era of novel β-lactam/β-lactamase inhibitor combinations.. Retrospective study of patients with K. pneumoniae BSI between January and August 2020 in 16 centres (CARBANEW study within the MULTI-SITA project).. Overall, 426 patients were included: 107/426 (25%) had carbapenem-resistant K. pneumoniae (CR-Kp) BSI and 319/426 (75%) had carbapenem-susceptible K. pneumoniae (CS-Kp) BSI. Crude cumulative 30 day mortality was 33.8% and 20.7% in patients with, respectively, CR-Kp BSI and CS-Kp BSI (P = 0.027). Carbapenemase production or carbapenemase-encoding genes were detected in 84/98 tested CR-Kp isolates (85.7%), mainly KPC (78/84; 92.9%). Ceftazidime/avibactam was the most frequently used appropriate therapy for CR-Kp BSI (80/107; 74.7%). In multivariable analyses, variables showing an unfavourable association with mortality after correction for multiple testing were age-adjusted Charlson comorbidity index (HR 1.20; 95% CI 1.10-1.31, P < 0.001) and Pitt score (HR 1.33; 95% CI 1.15-1.55, P < 0.001), but not carbapenem resistance (HR 1.28, 95% CI 0.74-2.22, P = 0.410). In a propensity score-matched analysis, there was no difference in mortality between patients appropriately treated with ceftazidime/avibactam for CR-Kp BSI and patients appropriately treated with other agents (mainly meropenem monotherapy or piperacillin/tazobactam monotherapy) for CS-Kp BSI (HR 1.07; 95% CI 0.50-2.29, P = 0.866).. Our results suggest that the increased mortality in CR-Kp BSI compared with CS-Kp BSI is not (or no longer) dependent on the type of therapy in areas where ceftazidime/avibactam-susceptible KPC-producing isolates are the most prevalent type of CR-Kp.

Topics: Anti-Bacterial Agents; Azabicyclo Compounds; Bacteremia; Bacterial Proteins; beta-Lactamase Inhibitors; beta-Lactamases; Carbapenems; Ceftazidime; Disease Susceptibility; Drug Combinations; Humans; Klebsiella Infections; Klebsiella pneumoniae; Retrospective Studies; Sepsis

The aim of this work was to investigate the activity of ceftazidime-avibactam (CZA) and aztreonam-avibactam (AZA) against bloodstream infections caused by carbapenem-resistant organisms (CROs).. The

Topics: Anti-Bacterial Agents; Azabicyclo Compounds; Aztreonam; beta-Lactamases; Carbapenems; Ceftazidime; Drug Combinations; Humans; Microbial Sensitivity Tests; Sepsis

Topics: Anti-Bacterial Agents; Azabicyclo Compounds; Aztreonam; beta-Lactamases; Ceftazidime; Drug Combinations; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Nebulizers and Vaporizers; Powders; Sepsis

We evaluated the efficacy of NXL104, a novel β-lactamase inhibitor, in combination with ceftazidime (CAZ) in two murine infection models (septicemia and thigh infection). We chose two KPC-producing Klebsiella pneumoniae strains (VA-361 and VA-406) showing MICs of CAZ of ≥256 μg/ml. Septicemia was induced by the intraperitoneal injection of KPC-producing K. pneumoniae followed 30 min later by a single subcutaneous treatment with CAZ alone or CAZ-NXL104 in ratios of 2:1, 4:1, 8:1, and 16:1. In this model, the median effective doses for 50% (ED(50)) of the animals for CAZ alone versus VA-361 and VA-406 were 1,578 and 709 mg/kg of body weight, respectively. When combined with NXL104 at 2:1, 4:1, 8:1, and 16:1 ratios, the CAZ ED(50)s for VA-361 and VA-406 were reduced to 8.1 and 3.5 mg/kg, 15.1 and 3.8 mg/kg, 16.9 and 7.2 mg/kg, and 29.5 and 12.1 mg/kg, respectively. For thigh infection, neutropenia was induced by the intraperitoneal injection of cyclophosphamide at days -4 and -1 preinfection. Infection was established by the intramuscular injection of KPC-producing K. pneumoniae into the right thigh. Mice were treated 1.5 h postinfection with either CAZ alone or CAZ-NXL104 at constant ratios of 4:1. When thighs were removed at 24 h postinfection, a >2-log CFU reduction was observed for mice treated with CAZ-NXL104 at doses of ≥128:32 mg/kg. In contrast, CAZ doses of ≥1,024 mg/kg were unable to reduce the numbers of CFU. Despite resistance to CAZ and possessing a complex β-lactamase background, NXL104 combined with CAZ proved to be very effective in murine models of infection due to contemporary highly resistant KPC-producing K. pneumoniae isolates.

Topics: Animals; Anti-Bacterial Agents; Azabicyclo Compounds; Ceftazidime; Disease Models, Animal; Female; Klebsiella Infections; Klebsiella pneumoniae; Mice; Microbial Sensitivity Tests; Sepsis