In vitro activity of amoxicillin combined with oral cephalosporins against endocarditis-associated E. faecalis clinical isolates
Objectives: Aminopenicillin associated with parenteral cephalosporins provides synergistic activity against Enterococcus faecalis. Oral consolidation treatment is an option for infective endocarditis E. faecalis (EFIE), but optimal oral regimen remains under debate. We aimed to assess the in vitro a...
| Authors: | ; ; ; ; ; ; ; ; ; ; ; ; ; |
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| Format: | Article |
| Status: | Accepted version |
| Publication date: | 2026 |
| Country: | España |
| Institution: | Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya) |
| Repository: | Recercat. Dipósit de la Recerca de Catalunya |
| OAI Identifier: | oai:dnet:recercat____::7a5e0b1162eb7fb35aa4176bbe1fa2b2 |
| Online Access: | https://hdl.handle.net/2445/229583 |
| Access Level: | Embargoed access |
| Keyword: | Endocarditis Amoxicil·lina Malalties bacterianes Amoxicillin Bacterial diseases |
| _version_ | 1878742769649844224 |
|---|---|
| author | Luque Paz, David |
| author2 | Cañas, María Alexandra Cuervo Requena, Guillermo Espasa, Mateu Hernández Meneses, Marta Quintana, Eduard Falces Salvador, Carles Tolosana, José M. (José María) Vidal, Bàrbara Perissinotti, Andrés Llopis Pérez, Jaime Moreno Camacho, Ma. Asunción García de la Mària, Cristina Miró Meda, José M. (José María), 1956- |
| author2_role | author author author author author author author author author author author author author |
| author_browse | Cañas, María Alexandra Cuervo Requena, Guillermo Espasa, Mateu Falces Salvador, Carles García de la Mària, Cristina Hernández Meneses, Marta Llopis Pérez, Jaime Luque Paz, David Miró Meda, José M. (José María), 1956- Moreno Camacho, Ma. Asunción Perissinotti, Andrés Quintana, Eduard Tolosana, José M. (José María) Vidal, Bàrbara |
| author_facet | Luque Paz, David Cañas, María Alexandra Cuervo Requena, Guillermo Espasa, Mateu Hernández Meneses, Marta Quintana, Eduard Falces Salvador, Carles Tolosana, José M. (José María) Vidal, Bàrbara Perissinotti, Andrés Llopis Pérez, Jaime Moreno Camacho, Ma. Asunción García de la Mària, Cristina Miró Meda, José M. (José María), 1956- |
| author_role | author |
| collection | Recercat. Dipósit de la Recerca de Catalunya |
| description | Objectives: Aminopenicillin associated with parenteral cephalosporins provides synergistic activity against Enterococcus faecalis. Oral consolidation treatment is an option for infective endocarditis E. faecalis (EFIE), but optimal oral regimen remains under debate. We aimed to assess the in vitro activity of combinations based on amoxicillin plus an oral cephalosporin, namely, cephalexin or cefixime, against E. faecalis strains. Methods: MIC and MBC values were determined against 6 clinical isolates of endocarditis-associated E. faecalis. Time-kill (TK) experiments were performed using amoxicillin (½MIC) plus cephalexin or cefixime at different concentrations (Cmax, ½Cmax and Cmin). Comparator regimens were amoxicillin/cefazolin and amoxicillin/ceftriaxone. TK experiments were carried out at standard (∼5 × 105 cfu/mL) and high inoculum (∼108 cfu/mL). Results: Using amoxicillin combined with Cmax, ½Cmax or Cmin of oral cephalosporin at standard inoculum, synergy or additivity was observed in 66, 33 and 0% of E. faecalis isolates with adjunctive cephalexin; and in 83, 50 and 33% of isolates with adjunctive cefixime, respectively. In comparator regimens, synergy was found in all isolates at standard inoculum. At high inoculum, amoxicillin/cefixime at Cmax had similar efficacy to amoxicillin/ceftriaxone, showing synergy in 50% of E. faecalis isolates, while amoxicillin/cephalexin at Cmax and amoxicillin/cefazolin only achieved synergy in 17% of isolates. Conclusions: The combination of amoxicillin/cefixime exhibits synergy in most E. faecalis strains at standard inoculum. Cefixime could represent an interesting adjunctive therapy to amoxicillin for oral consolidation treatment of EFIE. |
| eu_rights_str_mv | embargoedAccess |
| format | article |
| id | ES_fbeffd2ecbb8f5b41fba1fbf09e29fa4 |
| institution | Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya) |
| instname_str | Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya) |
| network_acronym_str | ES |
| network_name_str | España |
| oai_identifier_str | oai:dnet:recercat____::7a5e0b1162eb7fb35aa4176bbe1fa2b2 |
| publishDate | 2026 |
| publishDateSort | 2026 |
| publisher | Oxford University Press |
| publisherStr | Oxford University Press |
| reponame_str | Recercat. Dipósit de la Recerca de Catalunya |
| spelling | In vitro activity of amoxicillin combined with oral cephalosporins against endocarditis-associated E. faecalis clinical isolates Luque Paz, David Cañas, María Alexandra Cuervo Requena, Guillermo Espasa, Mateu Hernández Meneses, Marta Quintana, Eduard Falces Salvador, Carles Tolosana, José M. (José María) Vidal, Bàrbara Perissinotti, Andrés Llopis Pérez, Jaime Moreno Camacho, Ma. Asunción García de la Mària, Cristina Miró Meda, José M. (José María), 1956- Endocarditis Amoxicil·lina Malalties bacterianes Amoxicillin Bacterial diseases Objectives: Aminopenicillin associated with parenteral cephalosporins provides synergistic activity against Enterococcus faecalis. Oral consolidation treatment is an option for infective endocarditis E. faecalis (EFIE), but optimal oral regimen remains under debate. We aimed to assess the in vitro activity of combinations based on amoxicillin plus an oral cephalosporin, namely, cephalexin or cefixime, against E. faecalis strains. Methods: MIC and MBC values were determined against 6 clinical isolates of endocarditis-associated E. faecalis. Time-kill (TK) experiments were performed using amoxicillin (½MIC) plus cephalexin or cefixime at different concentrations (Cmax, ½Cmax and Cmin). Comparator regimens were amoxicillin/cefazolin and amoxicillin/ceftriaxone. TK experiments were carried out at standard (∼5 × 105 cfu/mL) and high inoculum (∼108 cfu/mL). Results: Using amoxicillin combined with Cmax, ½Cmax or Cmin of oral cephalosporin at standard inoculum, synergy or additivity was observed in 66, 33 and 0% of E. faecalis isolates with adjunctive cephalexin; and in 83, 50 and 33% of isolates with adjunctive cefixime, respectively. In comparator regimens, synergy was found in all isolates at standard inoculum. At high inoculum, amoxicillin/cefixime at Cmax had similar efficacy to amoxicillin/ceftriaxone, showing synergy in 50% of E. faecalis isolates, while amoxicillin/cephalexin at Cmax and amoxicillin/cefazolin only achieved synergy in 17% of isolates. Conclusions: The combination of amoxicillin/cefixime exhibits synergy in most E. faecalis strains at standard inoculum. Cefixime could represent an interesting adjunctive therapy to amoxicillin for oral consolidation treatment of EFIE. Oxford University Press https://hdl.handle.net/2445/229583 |
| spellingShingle | In vitro activity of amoxicillin combined with oral cephalosporins against endocarditis-associated E. faecalis clinical isolates Luque Paz, David Endocarditis Amoxicil·lina Malalties bacterianes Amoxicillin Bacterial diseases |
| status_str | acceptedVersion |
| title | In vitro activity of amoxicillin combined with oral cephalosporins against endocarditis-associated E. faecalis clinical isolates |
| title_full | In vitro activity of amoxicillin combined with oral cephalosporins against endocarditis-associated E. faecalis clinical isolates |
| title_fullStr | In vitro activity of amoxicillin combined with oral cephalosporins against endocarditis-associated E. faecalis clinical isolates |
| title_full_unstemmed | In vitro activity of amoxicillin combined with oral cephalosporins against endocarditis-associated E. faecalis clinical isolates |
| title_short | In vitro activity of amoxicillin combined with oral cephalosporins against endocarditis-associated E. faecalis clinical isolates |
| title_sort | In vitro activity of amoxicillin combined with oral cephalosporins against endocarditis-associated E. faecalis clinical isolates |
| topic | Endocarditis Amoxicil·lina Malalties bacterianes Amoxicillin Bacterial diseases |
| topic_facet | Endocarditis Amoxicil·lina Malalties bacterianes Amoxicillin Bacterial diseases |
| url | https://hdl.handle.net/2445/229583 |