title: Novel combinations of vancomycin plus ceftaroline or oxacillin against methicillin-resistant vancomycin-intermediate Staphylococcus aureus (VISA) and heterogeneous VISA.
abstract: We demonstrated a significant inverse correlation between vancomycin and beta-lactam susceptibilities in vancomycin-intermediate Staphylococcus aureus (VISA) and heterogeneous VISA (hVISA) isolates. Using time-kill assays, vancomycin plus oxacillin or ceftaroline was synergistic against 3 of 5 VISA and 1 of 5 hVISA isolates or 5 of 5 VISA and 4 of 5 hVISA isolates, respectively. Beta-lactam exposure reduced overall vancomycin-Bodipy (dipyrromethene boron difluoride [4,4-difluoro-4-bora-3a,4a-diaza-s-indacene] fluorescent dye) binding but may have improved vancomycin-cell wall interactions to improve vancomycin activity. Further research is warranted to elucidate the mechanism behind vancomycin and beta-lactam synergy.
authors: Anti-Infective Research Laboratory, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan, USA.
authors: B J
authors: BJ
authors: Werth
authors: C
authors: C
authors: Vidaillac
authors: K P
authors: KP
authors: Murray
authors: K L
authors: KL
authors: Newton
authors: G
authors: G
authors: Sakoulas
authors: P
authors: P
authors: Nonejuie
authors: J
authors: J
authors: Pogliano
authors: M J
authors: MJ
authors: Rybak
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001896:Boron Compounds; D002473:Cell Wall / Q000187:drug effects / Q000378:metabolism; D002511:Cephalosporins / Q000494:pharmacology*; D004338:Drug Combinations; D004357:Drug Synergism; D005456:Fluorescent Dyes; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development; D008826:Microbial Sensitivity Tests; D010068:Oxacillin / Q000494:pharmacology*; D014640:Vancomycin / Q000494:pharmacology*; D020713:Vancomycin Resistance / Q000187:drug effects; D000097583:Ceftaroline
chemical_list: D000900:Anti-Bacterial Agents; D001896:Boron Compounds; D002511:Cephalosporins; D004338:Drug Combinations; D005456:Fluorescent Dyes; D010068:Oxacillin; D014640:Vancomycin; D000097583:Ceftaroline; C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene