{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T16:26:20Z","timestamp":1788452780960,"version":"build-2803163510"},"reference-count":43,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,3,1]],"date-time":"2023-03-01T00:00:00Z","timestamp":1677628800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The continuous spread of carbapenem-resistant Klebsiella pneumoniae (CP-Kp) strains presents a severe challenge to the healthcare system due to limited therapeutic options and high mortality. Since its availability, ceftazidime\/avibactam (C\/A) has become a first-line option against KPC-Kp, but C\/A-resistant strains have been reported increasingly, especially with pneumonia or prior suboptimal blood exposure to C\/A treatment. A retrospective, observational study was conducted with all patients admitted to the Intensive Care Unit (ICU) dedicated to COVID-19 patients at the City of Health &amp; Sciences in Turin, between 1 May 2021 and 31 January 2022, with the primary endpoint to study strains with resistance to C\/A, and secondly to describe the characteristics of this population, with or without previous exposure to C\/A. Seventeen patients with colonization or invasive infection due to Klebsiella pneumoniae, C\/A resistance, and susceptibility to meropenem (MIC = 2 \u00b5g\/L) were included; the blaKPC genotype was detected in all isolates revealing D179Y mutation in the blaKPC-2 (blaKPC-33) gene. Cluster analysis showed that 16 out of the 17 C\/A-resistant KPC-Kp isolates belonged to a single clone. Thirteen strains (76.5%) were isolated in a 60-day period. Only some patients had a previous infection with non-mutant KPC at other sites (5; 29.4%). Eight patients (47.1%) underwent previous large-spectrum antibiotic treatment, and four patients (23.5%) had prior treatment with C\/A. The secondary spread of the D179Y mutation in the blaKPC-2 during the COVID-19 pandemic needs to be addressed constantly by an interdisciplinary interaction between microbiologists, infection control personnel, clinicians, and infectious diseases consultants to properly diagnose and treat patients.<\/jats:p>","DOI":"10.3390\/ijms24054767","type":"journal-article","created":{"date-parts":[[2023,3,2]],"date-time":"2023-03-02T03:29:00Z","timestamp":1677727740000},"page":"4767","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Ceftazidime-Avibactam (C\/A) Resistant, Meropenem Sensitive KPC-Producing Klebsiella pneumoniae in ICU Setting: We Are What We Are Treated with?"],"prefix":"10.3390","volume":"24","author":[{"given":"Silvia","family":"Corcione","sequence":"first","affiliation":[{"name":"Department of Medical Sciences, Infectious Diseases, University of Turin, 10124 Turin, Italy"},{"name":"School of Medicine, Tufts University School of Medicine, Boston, MA 02111, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6524-0481","authenticated-orcid":false,"given":"Ilaria","family":"De Benedetto","sequence":"additional","affiliation":[{"name":"Department of Medical Sciences, Infectious Diseases, University of Turin, 10124 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nour","family":"Shbaklo","sequence":"additional","affiliation":[{"name":"Department of Medical Sciences, Infectious Diseases, University of Turin, 10124 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giulia","family":"Torsello","sequence":"additional","affiliation":[{"name":"Department of Anesthesia, Intensive Care and Emergency\u2014\u2018Citt\u00e0 della Salute e della Scienza\u2019 Hospital, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3865-9519","authenticated-orcid":false,"given":"Tommaso","family":"Lupia","sequence":"additional","affiliation":[{"name":"Infectious Diseases Unit, Cardinal Massaia Hospital, 14100 Asti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8180-5075","authenticated-orcid":false,"given":"Gabriele","family":"Bianco","sequence":"additional","affiliation":[{"name":"Microbiology and Virology Unit, University Hospital Citt\u00e0 della Salute e della Scienza di Torino, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rossana","family":"Cavallo","sequence":"additional","affiliation":[{"name":"Microbiology and Virology Unit, University Hospital Citt\u00e0 della Salute e della Scienza di Torino, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7059-0622","authenticated-orcid":false,"given":"Luca","family":"Brazzi","sequence":"additional","affiliation":[{"name":"Department of Anesthesia, Intensive Care and Emergency\u2014\u2018Citt\u00e0 della Salute e della Scienza\u2019 Hospital, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9341-965X","authenticated-orcid":false,"given":"Giorgia","family":"Montrucchio","sequence":"additional","affiliation":[{"name":"Department of Anesthesia, Intensive Care and Emergency\u2014\u2018Citt\u00e0 della Salute e della Scienza\u2019 Hospital, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8338-0130","authenticated-orcid":false,"given":"Francesco Giuseppe","family":"De Rosa","sequence":"additional","affiliation":[{"name":"Department of Medical Sciences, Infectious Diseases, University of Turin, 10124 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"S28","DOI":"10.1093\/infdis\/jiw282","article-title":"The Epidemiology of Carbapenem-Resistant Enterobacteriaceae: The Impact and Evolution of a Global Menace","volume":"215","author":"Logan","year":"2017","journal-title":"J. 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