{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T20:18:16Z","timestamp":1773778696292,"version":"3.50.1"},"reference-count":26,"publisher":"Oxford University Press (OUP)","issue":"4","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:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,3,4]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>Oral second- and third-generation cephalosporins are increasingly used as transitional therapy for Escherichia coli bloodstream infection, particularly in patients with resistance and intolerance to first-line agents. However, many automated antimicrobial susceptibility testing (AST) systems only assess parenteral cephalosporins, potentially delaying transitions of care. Limited data exist on the correlation and surrogacy between parenteral and oral cephalosporin AST. We aimed to determine whether AST for parenteral cefazolin, ceftriaxone or cefotaxime can serve as surrogates to predict susceptibility for oral cephalosporins.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>E. coli blood isolates susceptible to parenteral third-generation cephalosporins were consecutively collected from unique patients from two health systems in Phoenix, AZ, USA from January 2021 to 2023. Broth microdilution was performed according to CLSI. Categorical agreement (CA) rates were calculated using cefazolin, ceftriaxone, or cefotaxime as the surrogate antibiotic for oral cephalosporins (cefuroxime, cefaclor, cefprozil, cefdinir, cefpodoxime, cefixime). Discrepancies were classified as minor errors (mE), major errors (ME), or very major errors (VME) per CLSI.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among 200 isolates, susceptibility to cefazolin at MIC \u22642\u2005mg\/L, cefazolin at MIC \u226416\u2005mg\/L, ceftriaxone and cefotaxime at MIC \u22641\u2005mg\/L were 43%, 91.5% and 100%, respectively. Cefazolin MIC \u22642\u2005mg\/L provided high CA across oral cephalosporins but excessive mE (25%\u201337%) and ME (20%\u201340%) rates. Ceftriaxone and cefotaxime achieved 100% CA for oral third-generation cephalosporins with mE rates within acceptable limits; however, CA was suboptimal for oral second-generation agents (83%\u201388%). No surrogate antibiotic met acceptable CLSI criteria due to lack of CA, however, ceftriaxone\/cefotaxime achieved acceptable limits in CA, mE, ME and VME.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Prediction of oral second-generation cephalosporins may warrant cefazolin MIC \u22642\u2005mg\/L, despite limitations regarding false resistance and susceptibility discordant. Ceftriaxone\/cefotaxime demonstrates a more reliable surrogate for predicting oral third-generation cephalosporins susceptibility. Future investigations are necessary to clinically corroborate these findings.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/jac\/dkag093","type":"journal-article","created":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T17:10:52Z","timestamp":1773767452000},"source":"Crossref","is-referenced-by-count":0,"title":["Predicting oral cephalosporin susceptibility in\n                    <i>Escherichia coli<\/i>\n                    blood isolates using parenteral cephalosporin susceptibility testing"],"prefix":"10.1093","volume":"81","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-2338-5491","authenticated-orcid":false,"given":"Tho H","family":"Pham","sequence":"first","affiliation":[{"name":"University of Arizona R. Ken Coit College of Pharmacy Department of Pharmacy Practice, , Phoenix, AZ ,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kyle C","family":"Molina","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, Scripps Health , San Diego, CA ,","place":["USA"]},{"name":"Department of Emergency Medicine, University of Colorado School of Medicine , Aurora, CO ,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8028-3554","authenticated-orcid":false,"given":"Vanthida","family":"Huang","sequence":"additional","affiliation":[{"name":"Midwestern University College of Pharmacy-Glendale Campus Department of Pharmacy Practice, , Glendale, AZ 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