Antimicrobial susceptibility of enterobacterales causing bloodstream infection in United States medical centres: comparison of aztreonam-avibactam with beta-lactams active against carbapenem-resistant enterobacterales

Abstract Background Bloodstream infection (BSI) is associated with poor outcomes especially when effective antimicrobial therapy and control of infection source are delayed. As the frequency of Enterobacterales producing metallo-β-lactamases (MBL) and/or OXA-48–like carbapenemases is increasing in s...

Full description

Saved in:
Bibliographic Details
Main Authors: Helio S. Sader, John H. Kimbrough, Rodrigo E. Mendes, Mariana Castanheira
Format: Article
Language:English
Published: BMC 2024-11-01
Series:BMC Infectious Diseases
Subjects:
Online Access:https://doi.org/10.1186/s12879-024-10133-5
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850061982234836992
author Helio S. Sader
John H. Kimbrough
Rodrigo E. Mendes
Mariana Castanheira
author_facet Helio S. Sader
John H. Kimbrough
Rodrigo E. Mendes
Mariana Castanheira
author_sort Helio S. Sader
collection DOAJ
description Abstract Background Bloodstream infection (BSI) is associated with poor outcomes especially when effective antimicrobial therapy and control of infection source are delayed. As the frequency of Enterobacterales producing metallo-β-lactamases (MBL) and/or OXA-48–like carbapenemases is increasing in some United States (US) medical centres, effective antimicrobials to treat the infections caused by these organisms are urgently needed. Aztreonam-avibactam is under clinical development for treatment of infections caused by Gram-negative bacteria, including MBL producers. Objectives To evaluate the antimicrobial susceptibility of Enterobacterales causing BSI in US medical centres and compare the activity of aztreonam-avibactam with ceftazidime-avibactam, meropenem-vaborbactam, imipenem-relebactam, cefiderocol, and other antimicrobials used to treat BSI. Methods 4,802 Enterobacterales were consecutively collected (1/patient) from 72 US medical centres in 2020–2022 and susceptibility tested by broth microdilution. Aztreonam-avibactam was tested with avibactam at a fixed concentration of 4 mg/L. A pharmacokinetic/pharmacodynamic susceptible breakpoint of ≤ 8 mg/L was applied for aztreonam-avibactam for comparison. Carbapenem-resistant Enterobacterales (CRE) isolates were tested for β-lactamase–encoding genes using Next-generation sequencing. Results Aztreonam-avibactam was highly active against Enterobacterales; only 2 isolates showed aztreonam-avibactam MICs > 8 mg/L: 1 meropenem-susceptible E. coli and 1 K. aerogenes (CRE). All carbapenemase producers and 98.0% of CRE were inhibited at an aztreonam-avibactam MIC of ≤ 8 mg/L. CRE susceptibility rates were 81.6% for ceftazidime-avibactam, 65.3% for meropenem-vaborbactam, 61.2% for imipenem-relebactam, and 87.8% for cefiderocol. Aztreonam-avibactam retained activity (MIC, ≤ 8 mg/L) against all (100.0%) meropenem-vaborbactam nonsusceptible (n = 17), 99.5% of imipenem-relebactam nonsusceptible (n = 206), and 90.0% of ceftazidime-avibactam nonsusceptible (n = 10) isolates. The most common carbapenemases were KPC-2/3 (57.1% of CREs), OXA-48–like (16.3%), and NDM (14.3%). A carbapenemase gene was not observed in 12.3% of CREs. Ceftazidime-avibactam and meropenem-vaborbactam were active against 100.0% of KPC producers, but ceftazidime-avibactam showed limited activity against MBL producers and meropenem-vaborbactam showed limited activity against OXA-48–like and MBL producers. The most active non–β-lactam comparators against CRE were gentamicin (49.0% susceptible) and amikacin (44.9% susceptible). Conclusions Aztreonam-avibactam demonstrated potent activity against a large collection of Enterobacterales isolated from patients with BSI in US hospitals, including CRE, MBL producers, and isolates resistant to recently approved β-lactamase inhibitor combinations.
format Article
id doaj-art-a98da34197b84688bdabda89653527cc
institution DOAJ
issn 1471-2334
language English
publishDate 2024-11-01
publisher BMC
record_format Article
series BMC Infectious Diseases
spelling doaj-art-a98da34197b84688bdabda89653527cc2025-08-20T02:50:03ZengBMCBMC Infectious Diseases1471-23342024-11-012411910.1186/s12879-024-10133-5Antimicrobial susceptibility of enterobacterales causing bloodstream infection in United States medical centres: comparison of aztreonam-avibactam with beta-lactams active against carbapenem-resistant enterobacteralesHelio S. Sader0John H. Kimbrough1Rodrigo E. Mendes2Mariana Castanheira3Element Iowa City (JMI Laboratories)Element Iowa City (JMI Laboratories)Element Iowa City (JMI Laboratories)Element Iowa City (JMI Laboratories)Abstract Background Bloodstream infection (BSI) is associated with poor outcomes especially when effective antimicrobial therapy and control of infection source are delayed. As the frequency of Enterobacterales producing metallo-β-lactamases (MBL) and/or OXA-48–like carbapenemases is increasing in some United States (US) medical centres, effective antimicrobials to treat the infections caused by these organisms are urgently needed. Aztreonam-avibactam is under clinical development for treatment of infections caused by Gram-negative bacteria, including MBL producers. Objectives To evaluate the antimicrobial susceptibility of Enterobacterales causing BSI in US medical centres and compare the activity of aztreonam-avibactam with ceftazidime-avibactam, meropenem-vaborbactam, imipenem-relebactam, cefiderocol, and other antimicrobials used to treat BSI. Methods 4,802 Enterobacterales were consecutively collected (1/patient) from 72 US medical centres in 2020–2022 and susceptibility tested by broth microdilution. Aztreonam-avibactam was tested with avibactam at a fixed concentration of 4 mg/L. A pharmacokinetic/pharmacodynamic susceptible breakpoint of ≤ 8 mg/L was applied for aztreonam-avibactam for comparison. Carbapenem-resistant Enterobacterales (CRE) isolates were tested for β-lactamase–encoding genes using Next-generation sequencing. Results Aztreonam-avibactam was highly active against Enterobacterales; only 2 isolates showed aztreonam-avibactam MICs > 8 mg/L: 1 meropenem-susceptible E. coli and 1 K. aerogenes (CRE). All carbapenemase producers and 98.0% of CRE were inhibited at an aztreonam-avibactam MIC of ≤ 8 mg/L. CRE susceptibility rates were 81.6% for ceftazidime-avibactam, 65.3% for meropenem-vaborbactam, 61.2% for imipenem-relebactam, and 87.8% for cefiderocol. Aztreonam-avibactam retained activity (MIC, ≤ 8 mg/L) against all (100.0%) meropenem-vaborbactam nonsusceptible (n = 17), 99.5% of imipenem-relebactam nonsusceptible (n = 206), and 90.0% of ceftazidime-avibactam nonsusceptible (n = 10) isolates. The most common carbapenemases were KPC-2/3 (57.1% of CREs), OXA-48–like (16.3%), and NDM (14.3%). A carbapenemase gene was not observed in 12.3% of CREs. Ceftazidime-avibactam and meropenem-vaborbactam were active against 100.0% of KPC producers, but ceftazidime-avibactam showed limited activity against MBL producers and meropenem-vaborbactam showed limited activity against OXA-48–like and MBL producers. The most active non–β-lactam comparators against CRE were gentamicin (49.0% susceptible) and amikacin (44.9% susceptible). Conclusions Aztreonam-avibactam demonstrated potent activity against a large collection of Enterobacterales isolated from patients with BSI in US hospitals, including CRE, MBL producers, and isolates resistant to recently approved β-lactamase inhibitor combinations.https://doi.org/10.1186/s12879-024-10133-5BacteraemiaMBLCeftazidime-avibactamCefiderocolEnterobacteralesBloodstream infection
spellingShingle Helio S. Sader
John H. Kimbrough
Rodrigo E. Mendes
Mariana Castanheira
Antimicrobial susceptibility of enterobacterales causing bloodstream infection in United States medical centres: comparison of aztreonam-avibactam with beta-lactams active against carbapenem-resistant enterobacterales
BMC Infectious Diseases
Bacteraemia
MBL
Ceftazidime-avibactam
Cefiderocol
Enterobacterales
Bloodstream infection
title Antimicrobial susceptibility of enterobacterales causing bloodstream infection in United States medical centres: comparison of aztreonam-avibactam with beta-lactams active against carbapenem-resistant enterobacterales
title_full Antimicrobial susceptibility of enterobacterales causing bloodstream infection in United States medical centres: comparison of aztreonam-avibactam with beta-lactams active against carbapenem-resistant enterobacterales
title_fullStr Antimicrobial susceptibility of enterobacterales causing bloodstream infection in United States medical centres: comparison of aztreonam-avibactam with beta-lactams active against carbapenem-resistant enterobacterales
title_full_unstemmed Antimicrobial susceptibility of enterobacterales causing bloodstream infection in United States medical centres: comparison of aztreonam-avibactam with beta-lactams active against carbapenem-resistant enterobacterales
title_short Antimicrobial susceptibility of enterobacterales causing bloodstream infection in United States medical centres: comparison of aztreonam-avibactam with beta-lactams active against carbapenem-resistant enterobacterales
title_sort antimicrobial susceptibility of enterobacterales causing bloodstream infection in united states medical centres comparison of aztreonam avibactam with beta lactams active against carbapenem resistant enterobacterales
topic Bacteraemia
MBL
Ceftazidime-avibactam
Cefiderocol
Enterobacterales
Bloodstream infection
url https://doi.org/10.1186/s12879-024-10133-5
work_keys_str_mv AT heliossader antimicrobialsusceptibilityofenterobacteralescausingbloodstreaminfectioninunitedstatesmedicalcentrescomparisonofaztreonamavibactamwithbetalactamsactiveagainstcarbapenemresistantenterobacterales
AT johnhkimbrough antimicrobialsusceptibilityofenterobacteralescausingbloodstreaminfectioninunitedstatesmedicalcentrescomparisonofaztreonamavibactamwithbetalactamsactiveagainstcarbapenemresistantenterobacterales
AT rodrigoemendes antimicrobialsusceptibilityofenterobacteralescausingbloodstreaminfectioninunitedstatesmedicalcentrescomparisonofaztreonamavibactamwithbetalactamsactiveagainstcarbapenemresistantenterobacterales
AT marianacastanheira antimicrobialsusceptibilityofenterobacteralescausingbloodstreaminfectioninunitedstatesmedicalcentrescomparisonofaztreonamavibactamwithbetalactamsactiveagainstcarbapenemresistantenterobacterales