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PubMed · 8815109

Selective isolation of vancomycin-resistant enterococci.

K G van Horn·C A Gedris·K M Rodney
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Abstract

Broth formulations of two media selective for enterococci, Enterococcel, M-Enterococcosel broths were supplemented with 6 micrograms of vancomycin per ml and evaluated for isolation of vancomycin-resistant enterococci (VRE). Each broth was challenged with various concentrations of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and vancomycin-susceptible and vancomycin-resistant enterococci and with 193 perianal specimens obtained from patients at risk in our institution for VRE colonization. Both the Enterococcosel and M-Enterococcus broths with vancomycin detected as few as 1 to 9 CFU of VRE while inhibiting growth of the other organisms tested. Enterococcus faecium organisms (MIC, > 256 micrograms/ml) were recovered from 66 perianal swab cultures in the enterococcosel-vancomycin broth, and VRE were recovered from 62 perianal swab cultures in the M-Enterococcus-vancomycin broth. Enterococcosel-vancomycin broth detected VRE in perianal specimens 48 h earlier than did M-Enterococcus-vancomycin broth. Enterococcosel broth with 6 micrograms of vancomycin per ml can be used for the rapid and selective isolation of VRE from surveillance specimens.

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Anti-Bacterial AgentsBacteriological TechniquesCross InfectionCulture MediaDrug Resistance, MicrobialEnterococcusGram-Positive Bacterial InfectionsHumansVancomycinComparative StudyJournal Article

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K G van Horn, C A Gedris, K M Rodney. 1996. Selective isolation of vancomycin-resistant enterococci.. https://doi.org/10.1128/jcm.34.4.924-927.1996

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