Many of you may misdiagnosed it as a vancomycin resistant enterococci (VRE). But, the special feature of this enterococcal isolate is vancomycin dependence i.e., the isolate can grow well when the presence of vancomycin and hence the isolate is called as, vancomycin-dependent enterococci (VDE). Carefully note the increased growth of enterococci with increasing concentration of vancomycin (image 3) and absence of growth in rest of the region of lawn made i.e., far away form vancomycin. Not only do these bacteria acquire the ability to utilize vancomycin for cell wall synthesis, but they also have the ability to revert to their resistant phenotypes when the drug is withdrawn. Interestingly, thus far these organisms are more of a curiosity than a significant clinical pathogen. Nevertheless, the outbreak of VDE at Johns Hopkins University in 1999 suggests that these bacteria do have potential for creating another layer of iatrogenic infectious disease complexity.
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