{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T04:56:04Z","timestamp":1788929764862,"version":"build-2803163510"},"reference-count":24,"publisher":"Oxford University Press (OUP)","issue":"12","license":[{"start":{"date-parts":[[2018,11,19]],"date-time":"2018-11-19T00:00:00Z","timestamp":1542585600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000060","name":"the National Institute of Allergy and Infectious Diseases","doi-asserted-by":"crossref","award":["T32 AI007613"],"award-info":[{"award-number":["T32 AI007613"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100000060","name":"the National Institute of Allergy and Infectious Diseases","doi-asserted-by":"crossref","award":["AI114994"],"award-info":[{"award-number":["AI114994"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100006108","name":"the National Center for Advancing Translational Sciences","doi-asserted-by":"crossref","award":["UL1 TR000457"],"award-info":[{"award-number":["UL1 TR000457"]}],"id":[{"id":"10.13039\/100006108","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2018,12,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Piperacillin-tazobactam-nonsusceptible (TZP-NS) Enterobacteriaceae are typically also resistant to ceftriaxone. We recently encountered bacteremias due to Escherichia coli (Ec) and Klebsiella pneumoniae (Kp) that were TZP-NS but ceftriaxone-susceptible (CRO-S).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We reviewed all Ec and Kp bacteremias from 2011 to 2015 at our center and assessed the prevalence, antimicrobial susceptibilities, genetic profiles, patient characteristics, treatments, and outcomes of TZP-NS\/CRO-S infections. We identified risk factors for TZP-NS\/CRO-S infections compared with Ec and Kp bacteremias that were TZP-S and CRO-S (Control Group 1) and compared outcomes of patients with TZP-NS\/CRO-S bacteremias, Control Group 1, and patients bacteremic with extended-spectrum \u03b2-lactamase (ESBL)\u2013producing Ec and Kp.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>There were 1857 Ec and Kp bacteremia episodes, of which 78 (4.2%) were TZP-NS\/CRO-S (Ec: 50\/1227 [4.1%]; Kp: 28\/630 [4.4%]). All TZP-NS\/CRO-S isolates were also ampicillin-sulbactam-NS. Of 32 TZP-NS\/CRO-S isolates that were sequenced, 28 (88%) harbored blaTEM-1 or blaSHV-1, none had an ESBL or AmpC \u03b2-lactamase gene, and many sequence types were represented. Independent risk factors for TZP-NS\/CRO-S bacteremia were exposure to \u03b2-lactam\/\u03b2-lactamase inhibitors (BL\/BLIs; adjusted odds ratio [aOR], 5.5; P &amp;lt; .001) and cephalosporins (aOR, 3.0; P = .04). Thirty-day mortality after TZP-NS\/CRO-S bacteremia was 25%, which was similar to control groups and was similar in patients treated empirically with BL\/BLIs compared with those treated with cephalosporins or carbapenems. Targeted therapy with cephalosporins did not yield a higher 30-day mortality rate than carbapenem therapy.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>TZP-NS\/CRO-S Ec and Kp are emerging causes of bacteremia, and further research is needed to better understand the epidemiology, resistance mechanisms, and clinical impact of these strains.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ofid\/ofy300","type":"journal-article","created":{"date-parts":[[2018,11,19]],"date-time":"2018-11-19T16:02:53Z","timestamp":1542643373000},"source":"Crossref","is-referenced-by-count":21,"title":["Epidemiology of Bloodstream Infections Caused by Escherichia coli and Klebsiella pneumoniae That Are Piperacillin-Tazobactam-Nonsusceptible but Ceftriaxone-Susceptible"],"prefix":"10.1093","volume":"5","author":[{"given":"Thomas M","family":"Baker","sequence":"first","affiliation":[{"name":"Division of Infectious Diseases, Weill Cornell Medicine, New York, New York"},{"name":"Clinical Immunology, Janssen Research & Development, Spring House, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wesley","family":"Rogers","sequence":"additional","affiliation":[{"name":"Department of Medicine, Weill Cornell Medicine, New York, New York"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kalyan D","family":"Chavda","sequence":"additional","affiliation":[{"name":"Public Health Research Institute, Rutgers New Jersey Medical School, Newark, New Jersey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lars F","family":"Westblade","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Weill Cornell Medicine, New York, New York"},{"name":"Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, New York"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephen G","family":"Jenkins","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Weill Cornell Medicine, New York, New York"},{"name":"Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, New York"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David P","family":"Nicolau","sequence":"additional","affiliation":[{"name":"Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, Connecticut"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barry N","family":"Kreiswirth","sequence":"additional","affiliation":[{"name":"Public Health Research Institute, Rutgers New Jersey Medical School, Newark, New Jersey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David P","family":"Calfee","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Weill Cornell Medicine, New York, 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