We used the broth microdilution method to determine the MICs of
daptomycin and 13 comparator agents against 319
methicillin-susceptible Staphylococcus aureus isolates, 201 methicillin-resistant S. aureus (MRSA) isolates, and 183
coagulase-negative staphylococci (CoNS). Isolates were consecutively collected from
bloodstream infections in 39 Spanish medical centers during a 3-month period (March through May 2008). Among MRSA, 1 isolate with intermediate susceptibility to
vancomycin and 6 isolates resistant to
linezolid were found. Nonsusceptibility to
teicoplanin was detected in 3.9% of CoNS.
Daptomycin was highly active against the staphylococcal blood isolates tested-all were inhibited at the
daptomycin susceptibility breakpoint of < or = 1 microg/mL.
Daptomycin retained its activity against the isolates that were resistant to
teicoplanin or
linezolid, or that had reduced susceptibility to
vancomycin. These data suggest that
daptomycin could be useful for the treatment of
bloodstream infections caused by staphylococci.