Highly Reproducible Bactericidal Activity Test Results by Using a Modified National Committee for Clinical Laboratory Standards Broth Macrodilution Technique

Highly reproducible bactericidal activity test results by using a modified National Committee for Clinical Laboratory Standards broth macrodilution technique.

Bactericidal testing historically has exhibited variable reproducibility, even when prior standardized methods were employed. Several modifications to the National Committee for Clinical Laboratory Standards (NCCLS) broth macrodilution method are proposed to improve reproducibility. Recommended changes from the approved NCCLS guidelines (M21-A and M26-A) include omitting serum supplementation o...

Comparison of Etest and National Committee for Clinical Laboratory Standards broth macrodilution method for antifungal susceptibility testing: enhanced ability to detect amphotericin B-resistant Candida isolates.

The National Committee for Clinical Laboratory Standards (NCCLS) proposed macrobroth reference method (M27P) for susceptibility testing of yeasts is technically difficult. We evaluated Etest, a simple agar-based MIC methodology, as a possible alternative. In studies of six yeast quality control strains, Etest yielded results identical to those obtained by the NCCLS reference method for both amp...

Antimicrobial susceptibility testing of Bacillus anthracis: comparison of results obtained by using the National Committee for Clinical Laboratory Standards broth microdilution reference and Etest agar gradient diffusion methods.

We determined the patterns of antimicrobial susceptibility of 65 isolates of Bacillus anthracis (50 historical and 15 recent U.S. clinical isolates) to nine antimicrobial agents using the National Committee for Clinical Laboratory Standards (NCCLS) broth microdilution reference method. The results for the 50 historical B. anthracis isolates obtained by the broth microdilution method were compar...

Effects of reduced cation supplement recommendations (National Committee for Clinical Laboratory Standards) on daptomycin antistaphylococcal activity.

Antifungal susceptibility testing using the E test: comparison with the broth macrodilution technique.

The National Committee for Clinical Laboratory Standards reference broth macrodilution method for antifungal susceptibility testing was compared with the E test by testing 86 clinical isolates of Candida spp. and Cryptococcus neoformans. The MIC agreement rates for the two methods for Candida spp. were 73-89% within +/-1 doubling dilution and 87-100% within +/-2 dilutions. For C. neoformans, ag...