Tentative interpretive criteria for the diffusion susceptibility test using 30-microgram netilmicin disks.
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).
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004058:Diffusion; D005839:Gentamicins / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests / Q000295:instrumentation; D009428:Netilmicin / Q000494:pharmacology*; D011549:Pseudomonas / Q000187:drug effects
D000900:Anti-Bacterial Agents; D005839:Gentamicins; D009428:Netilmicin