{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:58:42Z","timestamp":1760144322730,"version":"build-2065373602"},"reference-count":31,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,4,9]],"date-time":"2024-04-09T00:00:00Z","timestamp":1712620800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004587","name":"Spanish Ministry of Health, Instituto de Salud Carlos III, Spain","doi-asserted-by":"publisher","award":["PI19\/00965","CB21\/13\/00043"],"award-info":[{"award-number":["PI19\/00965","CB21\/13\/00043"]}],"id":[{"id":"10.13039\/501100004587","id-type":"DOI","asserted-by":"publisher"}]},{"name":"CIBERINFEC, Centro de Investigaci\u00f3n Biom\u00e9dica en Red en Enfermedades Infecciosas","award":["PI19\/00965","CB21\/13\/00043"],"award-info":[{"award-number":["PI19\/00965","CB21\/13\/00043"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background: As the anti-biofilm pharmacokinetic\/pharmacodynamic (PK\/PD) properties of antibiotics are not well-defined, we have evaluated the PK\/PD indices for different regimens of ceftazidime (CAZ; with\/without colistin) against Pseudomonas aeruginosa biofilm. Methods: We have used the Center for Disease Control and Prevention Biofilm Reactor with two susceptible (PAO1 and HUB-PAS) and one resistant (HUB-XDR) strains of P. aeruginosa. The regimens were CAZ monotherapies (mimicking a human dose of 2 g\/8 h, CAZ-IB; 6 g\/daily as continuous infusion at 50 mg\/L, CAZ-CI50; and 9 g\/daily at 70 mg\/L, CAZ-CI70) and CAZ-colistin combinations. Efficacy was correlated with the CAZ PK\/PD parameters. Results: CAZ-CI70 was the most effective monotherapy against CAZ-susceptible strains (\u0394log CFU\/mL 54\u20130 h = \u22124.15 \u00b1 0.59 and \u22123.05 \u00b1 0.5 for HUB-PAS and PAO1, respectively; p \u2264 0.007 vs. other monotherapies), and adding colistin improved the efficacy over CAZ monotherapy. CAZ monotherapies were ineffective against the HUB-XDR strain, and CAZ-CI50 plus colistin achieved higher efficacy than CAZ-IB with colistin. The PK\/PD index that correlated best with anti-biofilm efficacy was fAUC0\u201324h\/MIC (r2 = 0.78). Conclusions: CAZ exhibited dose-dependent anti-biofilm killing against P. aeruginosa, which was better explained by the fAUC0\u201324h\/MIC index. CAZ-CI provided benefits compared to CAZ-IB, particularly when using higher doses and together with colistin. CAZ monotherapies were ineffective against the CAZ-resistant strain, independently of the optimized strategy and only CAZ-CI plus colistin appeared useful for clinical practice.<\/jats:p>","DOI":"10.3390\/antibiotics13040344","type":"journal-article","created":{"date-parts":[[2024,4,9]],"date-time":"2024-04-09T08:55:12Z","timestamp":1712652912000},"page":"344","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Comparative Efficacy of Continuous Ceftazidime Infusion vs. Intermittent Bolus against In Vitro Ceftazidime-Susceptible and -Resistant Pseudomonas aeruginosa Biofilm"],"prefix":"10.3390","volume":"13","author":[{"given":"Cristina","family":"El Haj","sequence":"first","affiliation":[{"name":"Infectious Diseases Service, Laboratory of Experimental Infection, Hospital Universitari de Bellvitge and Bellvitge Biomedical Research Institute, Universitat de Barcelona, 08907 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eug\u00e8nia","family":"Agust\u00ed","sequence":"additional","affiliation":[{"name":"Infectious Diseases Service, Laboratory of Experimental Infection, Hospital Universitari de Bellvitge and Bellvitge Biomedical Research Institute, Universitat de Barcelona, 08907 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eva","family":"Benavent","sequence":"additional","affiliation":[{"name":"Infectious Diseases Service, Laboratory of Experimental Infection, Hospital Universitari de Bellvitge and Bellvitge Biomedical Research Institute, Universitat de Barcelona, 08907 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0649-3785","authenticated-orcid":false,"given":"Laura","family":"Soldevila-Boixader","sequence":"additional","affiliation":[{"name":"Infectious Diseases Service, Laboratory of Experimental Infection, Hospital Universitari de Bellvitge and Bellvitge Biomedical Research Institute, Universitat de Barcelona, 08907 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ra\u00fcl","family":"Rigo-Bonnin","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory, Hospital Universitari de Bellvitge and Bellvitge Biomedical Research Institute, Universitat de Barcelona, 08907 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fe","family":"Tubau","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Hospital Universitari de Bellvitge and CIBERES-Instituto de Salud Carlos III, 08907 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Benjam\u00edn","family":"Torrej\u00f3n","sequence":"additional","affiliation":[{"name":"Centres Cient\u00edfics i Tecnol\u00f2gics, Universitat de Barcelona, 08907 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8971-3167","authenticated-orcid":false,"given":"Jaime","family":"Esteban","sequence":"additional","affiliation":[{"name":"Department of Clinical Microbiology, IIS-Fundaci\u00f3n Jim\u00e9nez D\u00edaz, Universidad Aut\u00f3noma de Madrid, 28040 Madrid, Spain"},{"name":"Centro de Investigaci\u00f3n Biom\u00e9dica en Red en Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, 28029 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Oscar","family":"Murillo","sequence":"additional","affiliation":[{"name":"Infectious Diseases Service, Laboratory of Experimental Infection, Hospital Universitari de Bellvitge and Bellvitge Biomedical Research Institute, Universitat de Barcelona, 08907 Barcelona, Spain"},{"name":"Centro de Investigaci\u00f3n Biom\u00e9dica en Red en Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, 28029 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"204","DOI":"10.1038\/sj.clpt.6100247","article-title":"The Challenge of Treating Biofilm-Associated Bacterial Infections","volume":"82","author":"Patel","year":"2007","journal-title":"Clin. 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