{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T11:16:23Z","timestamp":1788261383794,"version":"build-2803163510"},"reference-count":20,"publisher":"Oxford University Press (OUP)","issue":"10","license":[{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100019211","name":"AbbVie","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100019211","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Resistance to ceftazidime\/avibactam and meropenem\/vaborbactam has been increasing among carbapenem-resistant Enterobacterales (CRE) in US hospitals recently. We evaluated the activity of aztreonam\/avibactam and comparators against isolates that were not susceptible to ceftazidime\/avibactam and\/or meropenem\/vaborbactam and against MBL-producing Enterobacterales.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A total of 80\u200a927 Enterobacterales isolates were consecutively collected (one per patient) in 2016\u20132024 from 103 US medical centres and susceptibility tested by broth microdilution in a monitoring laboratory. Among those, 194 (0.24%) were not susceptible to ceftazidime\/avibactam or meropenem\/vaborbactam, 115 (0.14%) were not susceptible to both ceftazidime\/avibactam and meropenem\/vaborbactam, and 832 (1.0%) isolates were carbapenem resistant. These isolates were screened for carbapenemase (CBase) genes by WGS.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Aztreonam\/avibactam was active against 91.9% of ceftazidime\/avibactam\u2013non-susceptible isolates (n\u200a=\u200a160), 94.0% of meropenem\/vaborbactam\u2013non-susceptible isolates (n\u200a=\u200a149), 98.1% of CRE and 98.4% of MBL producers (n\u200a=\u200a125). Cefiderocol retained activity against 78.8% of ceftazidime\/avibactam\u2013non-susceptible isolates, 83.2% of meropenem\/vaborbactam\u2013non-susceptible isolates, 94.7% of CRE and 82.1% of MBL producers. A CBase was identified in 159 (82.0%) of isolates not susceptible to ceftazidime\/avibactam or meropenem\/vaborbactam and in 683 (80.1%) of CREs. NDM (n\u200a=\u200a114; 58.8% of isolates) was the most common CBase type among isolates not susceptible to ceftazidime\/avibactam or meropenem\/vaborbactam. Notably, an MBL was identified in 36.1% (73\/202) of CRE collected in 2023\u20132024.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Aztreonam\/avibactam demonstrated potent activity against isolates not susceptible to ceftazidime\/avibactam and\/or meropenem\/vaborbactam as well as against CRE isolates, including MBL producers. The activities of other \u03b2-lactamase inhibitor combinations and cefiderocol were adversely affected by the alarming increase of MBL producers in some US hospitals.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/jac\/dkag308","type":"journal-article","created":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T11:46:38Z","timestamp":1787226398000},"source":"Crossref","is-referenced-by-count":0,"title":["Antimicrobial activity of aztreonam\/avibactam and molecular characterization of Enterobacterales not susceptible to ceftazidime\/avibactam and\/or meropenem\/vaborbactam from US medical centres (2016\u20132024)"],"prefix":"10.1093","volume":"81","author":[{"given":"Helio S","family":"Sader","sequence":"first","affiliation":[{"name":"Element Iowa City (JMI Laboratories) , North Liberty, IA ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Krisztina M","family":"Papp-Wallace","sequence":"additional","affiliation":[{"name":"Element Iowa City (JMI Laboratories) , North Liberty, IA ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John H","family":"Kimbrough","sequence":"additional","affiliation":[{"name":"Element Iowa City (JMI Laboratories) , North Liberty, IA ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dmitri","family":"Debabov","sequence":"additional","affiliation":[{"name":"AbbVie , North Chicago, IL ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rodrigo E","family":"Mendes","sequence":"additional","affiliation":[{"name":"Element Iowa City (JMI Laboratories) , North Liberty, IA ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mariana","family":"Castanheira","sequence":"additional","affiliation":[{"name":"Element Iowa City (JMI Laboratories) , North Liberty, IA 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