{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T19:14:06Z","timestamp":1784229246752,"version":"3.55.0"},"reference-count":21,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,3,4]],"date-time":"2026-03-04T00:00:00Z","timestamp":1772582400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:p>\n                    Extensively drug-resistant\n                    <jats:italic>Pseudomonas aeruginosa<\/jats:italic>\n                    (XDR-PA) present increasing incidence and limited therapeutic options, emerging as one of the serious public health threats worldwide. Here, we report a case of an elderly male patient with multiple primary diseases who developed a severe pneumonia following long-term bedrest due to an accidental tumble after cerebral infarction. In the meantime, plenty of Gram-negative bacilli were repeatedly detected in his sputum and rapidly spread into his blood. This strain was ultimately identified as New Delhi metallo-\u03b2-lactamase (NDM) positive XDR-PA. Subsequently, the patient was treated with a combination of ceftazidime-avibactam (2.5 g q8h) and high-dose aztreonam (2 g q6h) under close supervision on his hepatorenal function. No dose adjustment was made throughout the treatment course. After one week of therapy, the patient\u2019s symptoms were remarkably resolved, and finally discharged. This is the first evidence worldwide of successful treatment for severe pneumonia caused by NDM positive XDR-PA using this dose-dependent combination therapeutic regimen as far as we know. The accurate and timely results of carbapenemase typing and combined antimicrobial susceptibility testing support our bold attempt at this novel treatment regimen, ultimately making the patient recover with a favorable prognosis.\n                  <\/jats:p>","DOI":"10.3389\/fcimb.2026.1786251","type":"journal-article","created":{"date-parts":[[2026,3,4]],"date-time":"2026-03-04T06:57:54Z","timestamp":1772607474000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["High-dose aztreonam potentiates the combined antimicrobial activity of ceftazidime-avibactam against extensively drug-resistant New Delhi metallo-\u03b2-lactamase positive Pseudomonas aeruginosa in severe pneumonia treatment: the first global case report"],"prefix":"10.3389","volume":"16","author":[{"given":"Yifeng","family":"Liu","sequence":"first","affiliation":[{"name":"Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University","place":["Nanning, China"]},{"name":"Key Laboratory of Clinical Laboratory Medicine of Guangxi Medical University, Education Department of Guangxi Zhuang Autonomous Region","place":["Nanning, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cuiju","family":"Mo","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University","place":["Nanning, China"]},{"name":"Key Laboratory of Clinical Laboratory Medicine of Guangxi Medical University, Education Department of Guangxi Zhuang Autonomous Region","place":["Nanning, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meng","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University","place":["Nanning, China"]},{"name":"Key Laboratory of Clinical Laboratory Medicine of Guangxi Medical University, Education Department of Guangxi Zhuang Autonomous Region","place":["Nanning, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,3,4]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"153","DOI":"10.1016\/j.jgar.2018.01.014","article-title":"Early detection of a hypervirulent KPC-2-producing Pseudomonas aeruginosa ST235 in Brazil","volume":"12","author":"de Paula-Petroli","year":"2018","journal-title":"J. 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Drug Resist."},{"key":"B18","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2025.1618419","article-title":"Exploring the antibacterial potential of arthrocolins against extensively drug-resistant Pseudomonas aeruginosa: mechanistic insights into amino acid metabolism disruption","volume":"16","author":"Yang","year":"2025","journal-title":"Front. Microbiol."},{"key":"B19","doi-asserted-by":"publisher","first-page":"683","DOI":"10.1007\/s10096-020-04046-9","article-title":"Clinical and microbiological characteristics of adults with hospital-acquired pneumonia: a 10-year prospective observational study in China","volume":"40","author":"Yin","year":"2021","journal-title":"Eur. J. Clin. Microbiol. Infect. 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Resist."}],"container-title":["Frontiers in Cellular and Infection Microbiology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fcimb.2026.1786251\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,4]],"date-time":"2026-03-04T06:57:56Z","timestamp":1772607476000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fcimb.2026.1786251\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,4]]},"references-count":21,"alternative-id":["10.3389\/fcimb.2026.1786251"],"URL":"https:\/\/doi.org\/10.3389\/fcimb.2026.1786251","relation":{},"ISSN":["2235-2988"],"issn-type":[{"value":"2235-2988","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3,4]]},"article-number":"1786251"}}