Clinical glycopeptide-intermediate staphylococci tested against arbekacin, daptomycin, and tigecycline.
We examined the activity of arbekacin, daptomycin, tigecycline, and vancomycin against various Staphylococci isolates with glycopeptide-intermediate (n = 25) and heterogeneous susceptibilities (n = 22) (GISS and hGISS). The minimum inhibitory concentrations (MIC) of each antimicrobial was evaluated in time-kill experiments by using 4 randomly selected GISS isolates tested at 2 and 4 times their respective MIC. The MIC(90) microg/mL ranges for arbekacin, daptomycin, tigecycline, and vancomycin were 2 (0.25-4), 1 (0.0625-2), 0.5 (0.0625-2), and 8 (4-8), respectively. Time kill at 2 times the MIC demonstrated a mean log(10) colony forming units (CFU)/mL change of -2.98 +/- 0.708, -3.6 +/- 0.509, -2.48 +/- 0.647, and +1.14 +/- 0.1 arbekacin, daptomycin, tigecycline, and vancomycin, respectively. At 4 times the MIC, significant activity for all compounds was noted with a log(10) CFU/mL decrease range from 3.68 to 2.74 +/- 0.66. Overall, all the antimicrobials tested (with the exception of vancomycin) exhibited significant in vitro activity against GISS. These compounds may offer therapeutic options for the treatment of GISS.
Anti-Infective Research Laboratory, Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy and Health Sciences, Detroit, MI, USA.
Kerry L
KL
LaPlante
Michael J
MJ
Rybak
D000617:Aminoglycosides / Q000494:pharmacology*; D000704:Analysis of Variance; D000900:Anti-Bacterial Agents; D017576:Daptomycin / Q000494:pharmacology; D003982:Dibekacin / Q000031:analogs & derivatives* / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008911:Minocycline / Q000031:analogs & derivatives* / Q000494:pharmacology; D011336:Probability; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D013210:Staphylococcus / Q000145:classification* / Q000187:drug effects*; D000078304:Tigecycline; D014640:Vancomycin / Q000494:pharmacology
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D003982:Dibekacin; D014640:Vancomycin; D000078304:Tigecycline; D008911:Minocycline; C031986:arbekacin; D017576:Daptomycin