Induction of daptomycin heterogeneous susceptibility in Staphylococcus aureus by exposure to vancomycin

We studied vancomycin and daptomycin susceptibility in methicillin-resistant Staphylococcus aureus from patients exposed to vancomycin, glycopeptide-intermediate S. aureus, and S. aureus passaged in vancomycin-containing medium. A correlation between vancomycin and daptomycin heteroresistance was noted in some strains, suggesting that exposure of S. aureus to vancomycin may affect susceptibility to daptomycin.