Figure 1. Etest (AB Biodisk, Solna) vancomycin susceptibility–testing strip on sheep-blood agar inoculated with vancomycin-dependent enterococci (VDE). VDE strain can only grow contiguous to the end of the strip with the highest concentrations of vancomycin. Isolated colonies are also growing far from the strip; they represent revertants to vancomycin independence.
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