Disk diffusion versus broth microdilution susceptibility testing of XXXX and @entity6729 using seven oral antimicrobial agents: application of updated susceptibility guidelines of the National Committee for Clinical Laboratory Standards.

@entity2261 @entity115 @entity5504 @entity6727 @entity2929 @entity42285 @entity798 @entity6728 @entity9127 @entity10188 @entity869 @entity6729
Susceptibility testing of @entity6728 and @entity6729 is medium and inoculum dependent. Seven oral agents, @entity869 , @entity115 - @entity798 , @entity5504 , @entity42285 , @entity9127 , @entity6727 , and @entity2929 , were tested against 400 beta-lactamase-positive and -negative clinically significant respiratory strains of @entity6728 and 100 strains of @entity6729 . Sources of the strains included teaching and regional hospitals and a private laboratory. All strains were tested by broth microdilution and disk diffusion in haemophilus test medium for @entity6728 and agar for @entity6729 . Appropriate National Committee for Clinical Laboratory Standards (NCCLS) standards were followed. For @entity6728 , by disk diffusion and broth microdilution, respectively, 27 and 27% of strains were resistant to @entity869 , 37 and 5% were resistant to @entity2929 , 3 and 0.5% were resistant to @entity5504 , 2 and 0.5% were resistant to loracarbef, and 0% were resistant to @entity9127 , @entity6727 , and @entity10188 . beta-Lactamase-negative @entity869 -resistant strains were not observed. Of @entity6729 strains, 56% were resistant to @entity869 by disk diffusion and 95% were resistant by broth microdilution. This species was susceptible to all other agents tested by either method. The disagreements between disk diffusion results and MICs for @entity5504 , @entity869 , @entity2261 , and loracarbef that occurred with use of the 1990 NCCLS tables were resolved when the 1992 NCCLS tables were used.
