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Tentative interpretive criteria for the diffusion susceptibility test using 30-microgram netilmicin disks.

R N Jones·A L Barry·C Thornsberry
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Abstract

The disk diffusion inhibitory zone diameters for 10-microgram and 30-microgram netilmicin disks were correlated with minimum inhibitory concentrations against 471 clinical strains tested in cation-supplemented Mueller-Hinton broth. Regression line and error-rate bounded analysis favored the use of 30-microgram netilmicin disks utilizing zone size breakpoints of greater than or equal to 17 mm to indicate susceptibility (less than or equal to 8 microgram/ml) and less than or equal to 13 mm to indicate resistance (greater than 32 microgram/ml). Significant minor interpretive errors may be expected when testing populations of Pseudomonas that have netilmicin minimum inhibitory concentrations near the intermediate range (16 microgram/ml).

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Anti-Bacterial AgentsDiffusionGentamicinsMicrobial Sensitivity TestsNetilmicinPseudomonasJournal Article

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R N Jones, A L Barry, C Thornsberry. 1980. Tentative interpretive criteria for the diffusion susceptibility test using 30-microgram netilmicin disks.. https://doi.org/10.1128/aac.18.3.487

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