{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T01:45:04Z","timestamp":1774316704239,"version":"3.50.1"},"reference-count":28,"publisher":"Oxford University Press (OUP)","issue":"10","license":[{"start":{"date-parts":[[2025,8,6]],"date-time":"2025-08-06T00:00:00Z","timestamp":1754438400000},"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":[[2025,10,3]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Objectives<\/jats:title>\n                  <jats:p>Enterococcus faecium, a significant hospital associated pathogen, poses substantial treatment challenges. While combinations of ampicillin with cephalosporins are first-line therapies to treat Enterococcus faecalis high-mortality-rates infections, their efficacy against ampicillin-susceptible E. faecium (ASEfm) is less clear. This study evaluates the effectiveness of combining ampicillin with ceftriaxone or ceftaroline against ASEfm strains.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>Ten ASEfm bloodstream isolates from complicated infections were analyzed. Susceptibility to several antibiotics, including ceftriaxone, ceftaroline, and cefotaxime, was determined using standard methods. Time-kill assays were conducted to assess the synergistic and additive effects of ampicillin in combination with ceftriaxone or ceftaroline.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>Time-kill studies revealed that ampicillin combined with ceftaroline demonstrated synergistic and\/or additive effects in 7 out of 10 strains analyzed. In contrast, ampicillin combined with ceftriaxone showed less pronounced synergy, with only 3 out of 10 strains exhibiting synergistic and\/or additive effects.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>Our findings indicate that ampicillin combined with ceftaroline, or ceftriaxone provides synergistic activity against some but not all ASEfm clinical isolates. The observed synergy suggests that these combinations could offer a potential therapeutic option for challenging ASEfm infections.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/jac\/dkaf226","type":"journal-article","created":{"date-parts":[[2025,8,12]],"date-time":"2025-08-12T17:44:35Z","timestamp":1755020675000},"page":"2622-2629","source":"Crossref","is-referenced-by-count":4,"title":["Is ampicillin plus cephalosporins a therapeutic option for Ampicillin-Susceptible <i>Enterococcus faecium<\/i>?"],"prefix":"10.1093","volume":"80","author":[{"given":"Paula","family":"Bierge","sequence":"first","affiliation":[{"name":"Laboratori de Recerca en Microbiologia i Malalties Infeccioses, Hospital Universitari Parc Taul\u00ed, Institut d\u2019Investigaci\u00f3 i Innovaci\u00f3 Parc Taul\u00ed (I3PT-CERCA), Universitat Aut\u00f2noma de Barcelona , Sabadell ,","place":["Spain"]},{"name":"Institut de Biotecnologia i Biomedicina, Universitat Aut\u00f2noma de Barcelona , Cerdanyola del Vall\u00e8s ,","place":["Spain"]}]},{"given":"Inmaculada","family":"G\u00f3mez-S\u00e1nchez","sequence":"additional","affiliation":[{"name":"Laboratori de Recerca en Microbiologia i Malalties Infeccioses, Hospital Universitari Parc Taul\u00ed, Institut d\u2019Investigaci\u00f3 i Innovaci\u00f3 Parc Taul\u00ed (I3PT-CERCA), Universitat Aut\u00f2noma de Barcelona , Sabadell ,","place":["Spain"]},{"name":"Institut de Biotecnologia i Biomedicina, Universitat Aut\u00f2noma de Barcelona , Cerdanyola del Vall\u00e8s ,","place":["Spain"]}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0585-9469","authenticated-orcid":false,"given":"Cristina","family":"Garcia de la M\u00e0ria","sequence":"additional","affiliation":[{"name":"Departament de Microbiologia, Hospital Clinic-IDIBAPS, Universitat de Barcelona , Barcelona ,","place":["Spain"]}]},{"given":"Miquel","family":"S\u00e1nchez-Osuna","sequence":"additional","affiliation":[{"name":"Laboratori de Recerca en Microbiologia i Malalties Infeccioses, Hospital Universitari Parc Taul\u00ed, Institut d\u2019Investigaci\u00f3 i Innovaci\u00f3 Parc Taul\u00ed (I3PT-CERCA), Universitat Aut\u00f2noma de Barcelona , Sabadell ,","place":["Spain"]},{"name":"Institut de Biotecnologia i Biomedicina, Universitat Aut\u00f2noma de Barcelona , Cerdanyola del Vall\u00e8s ,","place":["Spain"]}]},{"given":"Silvia","family":"Capilla","sequence":"additional","affiliation":[{"name":"Departament de Microbiologia. Laboratoris Cl\u00ednics-UDIAT, Hospital Universitari Parc Taul\u00ed, Institut d\u2019Investigaci\u00f3 i Innovaci\u00f3 Parc Taul\u00ed (I3PT-CERCA), Universitat Aut\u00f2noma de Barcelona , Sabadell ,","place":["Spain"]}]},{"given":"Antonio","family":"Casabella","sequence":"additional","affiliation":[{"name":"Departament de Microbiologia. Laboratoris Cl\u00ednics-UDIAT, Hospital Universitari Parc Taul\u00ed, Institut d\u2019Investigaci\u00f3 i Innovaci\u00f3 Parc Taul\u00ed (I3PT-CERCA), Universitat Aut\u00f2noma de Barcelona , Sabadell ,","place":["Spain"]}]},{"given":"Mateu","family":"Espasa","sequence":"additional","affiliation":[{"name":"Departament de Microbiologia. Laboratoris Cl\u00ednics-UDIAT, Hospital Universitari Parc Taul\u00ed, Institut d\u2019Investigaci\u00f3 i Innovaci\u00f3 Parc Taul\u00ed (I3PT-CERCA), Universitat Aut\u00f2noma de Barcelona , Sabadell ,","place":["Spain"]}]},{"given":"Carla","family":"Novais","sequence":"additional","affiliation":[{"name":"UCIBIO- Unidade de Ci\u00eancias Biomoleculares Aplicadas, Faculdade de Farm\u00e1cia, Universidade do Porto , Porto ,","place":["Portugal"]},{"name":"Laborat\u00f3rio Associado i4HB\u2014Instituto para a Sa\u00fade e a Bioeconomia, Faculdade de Farm\u00e1cia, Universidade do Porto , Porto ,","place":["Portugal"]}]},{"given":"Jose M","family":"Mir\u00f3","sequence":"additional","affiliation":[{"name":"Departament de Microbiologia, Hospital Clinic-IDIBAPS, Universitat de Barcelona , Barcelona ,","place":["Spain"]}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3561-630X","authenticated-orcid":false,"given":"Oscar Q","family":"Pich","sequence":"additional","affiliation":[{"name":"Laboratori de Recerca en Microbiologia i Malalties Infeccioses, Hospital Universitari Parc Taul\u00ed, Institut d\u2019Investigaci\u00f3 i Innovaci\u00f3 Parc Taul\u00ed (I3PT-CERCA), Universitat Aut\u00f2noma de Barcelona , Sabadell ,","place":["Spain"]},{"name":"Institut de Biotecnologia i Biomedicina, Universitat Aut\u00f2noma de Barcelona , Cerdanyola del Vall\u00e8s ,","place":["Spain"]}]},{"given":"Oriol","family":"Gasch","sequence":"additional","affiliation":[{"name":"Servei de Malalties Infeccioses, Hospital Universitari Parc Taul\u00ed, Institut d\u2019Investigaci\u00f3 i Innovaci\u00f3 Parc Taul\u00ed (I3PT-CERCA), Universitat Aut\u00f2noma de Barcelona , Sabadell ,","place":["Spain"]}]}],"member":"286","published-online":{"date-parts":[[2025,8,6]]},"reference":[{"key":"2025100314254153900_dkaf226-B1","doi-asserted-by":"publisher","first-page":"266","DOI":"10.1038\/nrmicro2761","article-title":"The rise of the Enterococcus: beyond vancomycin resistance","volume":"10","author":"Arias","year":"2012","journal-title":"Nat Rev Microbiol"},{"key":"2025100314254153900_dkaf226-B2","author":"World Health Organization"},{"key":"2025100314254153900_dkaf226-B3","doi-asserted-by":"publisher","first-page":"1221","DOI":"10.1586\/14787210.2014.956092","article-title":"Mechanisms of antibiotic resistance in enterococci","volume":"12","author":"Miller","year":"2014","journal-title":"Expert Rev Anti Infect Ther"},{"key":"2025100314254153900_dkaf226-B4","doi-asserted-by":"publisher","first-page":"173","DOI":"10.1161\/01.cir.10.2.173","article-title":"Antibiotic therapy of bacterial endocarditis. 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