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Use of the E test for methicillin sensitivity testing.

G E Bignardi·U Riley·C S Easmon
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Abstract

Performance of the E test for methicillin sensitivity testing was investigated using 21 methicillin-resistant and 28 methicillin-sensitive staphylococci. Thirty of the strains had previously given equivocal results with a strip diffusion method. The E test performed well with Mueller-Hinton agar plates incubated at 30 degrees C for 24 h but only after supplementation with 5% NaCl. Testing on agar without salt was necessary for the recognition of methicillin resistance in one strain. We recommend a breakpoint of 4 mg/L and heavy inocula. The E test can be controlled by testing a control strain on the same plate.

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Culture MediaDiffusionMethicillin ResistanceMicrobial Sensitivity TestsReagent StripsStaphylococcus aureusbeta-LactamasesJournal Article

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G E Bignardi, U Riley, C S Easmon. 1993. Use of the E test for methicillin sensitivity testing.. https://doi.org/10.1093/jac%2F32.1.37

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