Evaluation of the Vitek GPS-TA card for laboratory detection of high-level gentamicin and streptomycin resistance in enterococci.
The Vitek GPS-TA card (Vitek Systems, Hazelwood, Mo.) was compared with single-concentration broth microdilution and disk diffusion methods using high-content disks for the detection of high-level resistance to gentamicin and streptomycin in 99 isolates of enterococci (81 Enterococcus faecalis isolates and 18 Enterococcus faecium isolates). The GPS-TA card accurately detected high-level resistance to gentamicin, but not streptomycin, in E. faecalis. When streptomycin is being considered for therapy, either disk diffusion or time-kill studies should be used to confirm susceptible results obtained by Vitek testing. Additional studies are needed to determine the best method for testing E. faecium isolates.
Metchock
B
B
Department of Pathology, Emory University School of Medicine, Atlanta, Georgia.
McGowan
J E
JE
D004352:Drug Resistance, Microbial; D013293:Enterococcus faecalis / Q000187:drug effects* / Q000302:isolation & purification; D016984:Enterococcus faecium / Q000187:drug effects* / Q000302:isolation & purification; D005839:Gentamicins / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D013307:Streptomycin / Q000494:pharmacology*
D005839:Gentamicins; D013307:Streptomycin