{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T06:20:22Z","timestamp":1793859622307,"version":"4.6.1"},"reference-count":31,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,7,11]],"date-time":"2023-07-11T00:00:00Z","timestamp":1689033600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Shionogi &amp; Co., Ltd., Osaka, Japan","award":["491454339"],"award-info":[{"award-number":["491454339"]}]},{"DOI":"10.13039\/501100001659","name":"DFG","doi-asserted-by":"publisher","award":["491454339"],"award-info":[{"award-number":["491454339"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background: Cefiderocol is a novel siderophore cephalosporin with potent activity against multi-drug-resistant Gram-negative pathogens including carbapenem-resistant Acinetobacter baumannii (CRAB). Methods: The susceptibility of 313 non-duplicate CRAB isolates with defined carbapenem resistance mechanisms from a global collection to cefiderocol, ceftazidime, ceftazidime\/avibactam, ceftolozane\/tazobactam, ciprofloxacin, colistin, imipenem\/relebactam, meropenem, meropenem\/vaborbactam, minocycline, and piperacillin\/tazobactam was determined using the broth microdilution method. Isolates were obtained from various body sites from patients in 47 countries in five world regions between 2012 and 2016. The identification of carbapenem resistance mechanisms and assignment to A. baumannii international clonal lineages were based on whole genome sequencing. Results: Cefiderocol showed greater activity than comparator antimicrobials of the \u03b2-lactam class, including novel \u03b2-lactams combined with \u03b2-lactamase inhibitors, ciprofloxacin, and minocycline. Cefiderocol MIC50 and MIC90 values were 0.5 mg\/L and 4 mg\/L, respectively, while colistin had comparable activity with a higher MIC50 at 1 mg\/L and a lower MIC90 value of 2 mg\/L. Many isolates with elevated cefiderocol MICs \u2265 4 mg\/L represented A. baumannii international clone (IC) 1 and harbored a metallo-\u03b2-lactamase. Conclusions: While cefiderocol is a useful addition to the limited armamentarium of drugs targeting this problematic pathogen, a considerable part of CRAB isolates had elevated MIC values in a range of 4 -&gt; 32 mg\/L, including all isolates with a metallo-\u03b2-lactamase.<\/jats:p>","DOI":"10.3390\/antibiotics12071172","type":"journal-article","created":{"date-parts":[[2023,7,11]],"date-time":"2023-07-11T01:40:02Z","timestamp":1689039602000},"page":"1172","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["In Vitro Activity of Cefiderocol against a Global Collection of Carbapenem-Resistant Acinetobacter baumannii Isolates"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7732-4762","authenticated-orcid":false,"given":"Harald","family":"Seifert","sequence":"first","affiliation":[{"name":"Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50935 Cologne, Germany"},{"name":"German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, 38124 Braunschweig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carina","family":"M\u00fcller","sequence":"additional","affiliation":[{"name":"Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50935 Cologne, Germany"},{"name":"German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, 38124 Braunschweig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Danuta","family":"Stefanik","sequence":"additional","affiliation":[{"name":"Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50935 Cologne, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8677-9454","authenticated-orcid":false,"given":"Paul G.","family":"Higgins","sequence":"additional","affiliation":[{"name":"Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50935 Cologne, Germany"},{"name":"German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, 38124 Braunschweig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9756-7385","authenticated-orcid":false,"given":"Esther","family":"Wohlfarth","sequence":"additional","affiliation":[{"name":"Antiinfectives Intelligence GmbH, 51105 Cologne, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0613-925X","authenticated-orcid":false,"given":"Michael","family":"Kresken","sequence":"additional","affiliation":[{"name":"Antiinfectives Intelligence GmbH, 51105 Cologne, Germany"},{"name":"Rheinische Fachhochschule gGmbH, 50676 Cologne, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"538","DOI":"10.1128\/CMR.00058-07","article-title":"Acinetobacter baumannii: Emergence of a successful pathogen","volume":"21","author":"Peleg","year":"2008","journal-title":"Clin. 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