In vitro activity of ceftobiprole and dalbavancin against a collection of coagulase-negative staphylococci isolates from clinical samples with reduced susceptibility to daptomycin and/or resistant to linezolid or glycopeptides

Abstract

Introduction

The aim was to investigate the in vitro activity of ceftobiprole and dalbavancin against a collection of coagulase-negative staphylococci (CoNS) isolates with reduced susceptibility to daptomycin or resistant to linezolid and/or glycopeptides.

Methods

A total of 228 CoNS were tested using the Vitek-2 AST-626 cards (bioMérieux) and MIC of daptomycin, linezolid, vancomycin and teicoplanin were confirmed by Etest Strips (bioMérieux). Susceptibility testing for ceftobiprole and dalbavancin were performed by CLSI broth microdilution methodology. Results were interpreted according to 2021 EUCAST clinical breakpoints.

Results

Ceftobiprole and dalbavancin were active against 96.0% and 93.0% of CoNS, respectively, MIC₉₀ were 2 and 0.125 mg/L. MICs of ceptobiprole were higher against S. hominis and S. haemolyticus (MIC₉₀ 4 mg/L). Dalbavancin exhibited higher MICs against S. haemolyticus and CoNS with reduced susceptibility to daptomycin and resistant to teicoplanin.

Conclusion

Ceftobiprole and dalbavancin demonstrated a high in vitro activity against our collection of CoNS isolates.

Resumen

Introducción

El objetivo fue evaluar la actividad in vitro de dalbavancina y ceftobiprol frente a estafilococos coagulasa negativos (ECN) con sensibilidad disminuida a daptomicina y/o resistentes a linezolid o glucopéptidos.

Métodos

Se testó la sensibilidad de 228 ECN con tarjetas VITEK®2 AST-626 (bioMérieux) y las CMI de daptomicina, linezolid, vancomicina y teicoplanina fueron confirmadas con tiras Etest® (bioMérieux). El ensayo de sensibilidad frente a ceftobiprol y dalbavancina se realizó mediante microdilución en caldo (metodología CLSI). Los resultados se interpretaron siguiendo los puntos de corte de EUCAST 2021.

Resultados

Ceftobiprol y dalbavancina fueron activos en el 96,0 y 93% de ECN, las CMI₉₀ fueron 2 y 0,125 mg/L, respectivamente. Las CMI de ceftobiprol fueron superiores en Staphylococcus hominis y Staphylococcus haemolyticus (CMI₉₀ 4 mg/L). Dalbavancina exhibió mayores CMI en S. haemolyticus y en ECN con sensibilidad disminuida a daptomicina o resistentes a teicoplanina.

Conclusión

Ceftobiprol y dalbavancina han demostrado una potente actividad in vitro frente a esta colección de ECN.