{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T15:51:34Z","timestamp":1791820294799,"version":"4.3.4"},"reference-count":36,"publisher":"Oxford University Press (OUP)","issue":"2","license":[{"start":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T00:00:00Z","timestamp":1773792000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,2]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Ceftolozane-tazobactam and ceftazidime-avibactam are considered first-line treatment for multidrug-resistant (MDR) and\/or difficult-to-treat resistant (DTR) Pseudomonas aeruginosa infections. Conflicting results in terms of clinical outcome and resistance development emerged from real-world comparative studies. We performed a systematic review with meta-analysis to compare ceftolozane-tazobactam and ceftazidime-avibactam in the treatment of MDR\/DTR P. aeruginosa infections.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Two authors independently searched PubMed-MEDLINE and Scopus databases from inception to 18 November 2025 to retrieve studies comparing ceftolozane-tazobactam versus ceftazidime-avibactam in the management of MDR\/DTR P. aeruginosa infections. Clinical cure was set as the primary outcome, whereas 90-day resistance development, microbiological failure, and the 30-day mortality rate were set as the secondary outcomes. Meta-analysis was performed by pooling the odds ratios (ORs) retrieved from studies providing adjustment for confounders by means of a random-effects model with the inverse variance method. The risk of bias in the included studies was independently assessed using the RoB 2.0 and the ROBINS-I tools.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among a total of 1193 articles screened, 6 observational studies were retrieved and included (n = 1161; 644 receiving ceftolozane-tazobactam vs 517 receiving ceftazidime-avibactam). Ceftolozane-tazobactam showed a higher clinical cure rate than ceftazidime-avibactam (n = 4; OR, 1.82 [95% confidence interval, 1.10\u20132.99]; I2 = 25.3%). No difference emerged in terms of microbiological failure (n = 2; OR, 0.66 [95% confidence interval, .36\u20131.19]; I2 = 21.9%), 90-day resistance development (n = 3; OR, 1.11 [.51\u20132.42]; I2 = 50.0%), or 30-day mortality rate (n = 4; OR, 1.00 [.89\u20131.12]; I2 = 0.0%).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Our meta-analysis showed that, after appropriate adjustment for confounders, ceftolozane-tazobactam could grant a higher clinical cure rate than ceftazidime-avibactam in the treatment of MDR\/DTR P. aeruginosa infections.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/cid\/ciag194","type":"journal-article","created":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T00:01:57Z","timestamp":1773792117000},"page":"e270-e281","source":"Crossref","is-referenced-by-count":5,"title":["Comparison of Ceftolozane-Tazobactam and Ceftazidime-Avibactam in the Treatment of Multidrug-Resistant\/Difficult-to-Treat Resistant\n                    <i>Pseudomonas aeruginosa<\/i>\n                    Infections: A Systematic Review and Meta-analysis"],"prefix":"10.1093","volume":"83","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3018-3779","authenticated-orcid":false,"given":"Milo","family":"Gatti","sequence":"first","affiliation":[{"name":"Department of Medical and Surgical Sciences, Alma Mater Studiorum, University of Bologna , Bologna ,","place":["Italy"]},{"name":"Clinical Pharmacology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna , Bologna ,","place":["Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-6856-8936","authenticated-orcid":false,"given":"Riccardo","family":"De Paola","sequence":"additional","affiliation":[{"name":"Clinical Pharmacology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna , Bologna ,","place":["Italy"]},{"name":"Specialisation School of Clinical Pharmacology and Toxicology, Alma Mater Studiorum, University of Bologna , Bologna ,","place":["Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-8784-9070","authenticated-orcid":false,"given":"Beatrice","family":"Giorgi","sequence":"additional","affiliation":[{"name":"Clinical Pharmacology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna , Bologna ,","place":["Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6966-7167","authenticated-orcid":false,"given":"Federico","family":"Pea","sequence":"additional","affiliation":[{"name":"Department of Medical and Surgical Sciences, Alma Mater Studiorum, University of Bologna , Bologna ,","place":["Italy"]},{"name":"Clinical Pharmacology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna , Bologna ,","place":["Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,3,18]]},"reference":[{"key":"2026101211315431200_ciag194-B1","doi-asserted-by":"crossref","first-page":"e00031-19","DOI":"10.1128\/CMR.00031-19","article-title":"Epidemiology and treatment of multidrug-resistant and extensively drug-resistant Pseudomonas aeruginosa infections","volume":"32","author":"Horcajada","year":"2019","journal-title":"Clin Microbiol Rev"},{"key":"2026101211315431200_ciag194-B2","doi-asserted-by":"crossref","first-page":"e00233-24","DOI":"10.1128\/cmr.00233-24","article-title":"Current and future options for the treatment of serious infections due to carbapenem-resistant Pseudomonas aeruginosa","volume":"38","author":"Horcajada","year":"2025","journal-title":"Clin Microbiol Rev"},{"key":"2026101211315431200_ciag194-B3","doi-asserted-by":"crossref","first-page":"1797","DOI":"10.1016\/j.cmi.2025.08.018","article-title":"How do I manage difficult-to-treat Pseudomonas aeruginosa infections? Key questions for today's clinicians","volume":"31","author":"Horcajada","year":"2025","journal-title":"Clin Microbiol Infect"},{"key":"2026101211315431200_ciag194-B4","doi-asserted-by":"crossref","first-page":"268","DOI":"10.1111\/j.1469-0691.2011.03570.x","article-title":"Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria: an international expert proposal for interim standard definitions for acquired resistance","volume":"18","author":"Magiorakos","year":"2012","journal-title":"Clin Microbiol Infect"},{"key":"2026101211315431200_ciag194-B5","doi-asserted-by":"crossref","first-page":"1803","DOI":"10.1093\/cid\/ciy378","article-title":"Difficult-to-treat resistance in gram-negative bacteremia at 173 US hospitals: retrospective cohort analysis of prevalence, predictors, and outcome of resistance to all first-line agents","volume":"67","author":"Kadri","year":"2018","journal-title":"Clin Infect Dis"},{"key":"2026101211315431200_ciag194-B6","doi-asserted-by":"crossref","first-page":"564","DOI":"10.1097\/QCO.0000000000000966","article-title":"MDR\/XDR\/PDR or DTR? 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