In June 1987, the Antimicrobial Susceptibility Testing Subcommittee of the National Committee for Clinical Laboratory Standards (NCCLS) established a fastidious-organism working group expressly for the purpose of addressing issues related to in vitro susceptibility tests with aerobic or microaerophilic bacteria that do not grow well on unsupplemented Mueller-Hinton (MH) media. The fastidious-or...

The effects of inocula and media on the activities of ampicillin, penicillin, chloramphenicol and co-trimoxazole against Haemophilus influenzae were examined in vitro. Two inocula and four media were tested by the disk diffusion, broth dilution, and agar dilution methods. Chloramphenicol activity versus H. influenzae was least affected by changes in inocula and media, whereas co-trimoxazole was...

Seven commonly used antimicrobial susceptibility testing methods were used to test the susceptibility of 150 isolates of Pseudomonas aeruginosa against gentamicin, tobramycin, amikacin, carbenicillin, and piperacillin. Results were compared with respect to the susceptibility characteristics of the population of isolates as defined by each method. Conventional methods included agar disk diffusio...

background and objective: reports on mrsa strains are increasing worldwide. the aim of this study was to find the prevalence of mrsa strains isolated from clinical specimens and to evaluate their resistance profile. additionally we compared the phenotypic and genotypic methods for detection of methicillin resistance. materials and methods: in this cross-sectional study, a total of 41 isolates o...

background and objectives:increased antibiotic resistance as a result of using antimicrobial drugs and also their various adverse effects has caused that in recent years, investigation of medicinal plants beconsidered for discovering new medicinal resources against bacterial infections. this study was performed with the objective of determining the antimicrobial activity of aqueous and ethanoli...

Tiamulin is a pleuromutilin derivative used in veterinary practice for the control and specific therapy of infections in swine. This report summarizes studies to establish standardized susceptibility testing methods, interpretive criteria, and reagent details for use in veterinary methods recently developed by the National Committee for Clinical Laboratory Standards (NCCLS) (standards M31-A and...

This solithromycin quality control study was performed to establish quality control (QC) ranges for the N. gonorrhoeae ATCC 49226 control strain for MIC agar dilution testing (AD) and zones by disk diffusion testing (DD). The following ranges were established: AD, 0.03 to 0.25 μg/ml, and DD, 33 to 43 mm. In January 2015, the CLSI Subcommittee on Antimicrobial Susceptibility Testing approved the...

This study evaluated the antimicrobial activity of Ficus exasperata and compared the efficacy of ethanol and hexane extracts on five microbial isolates. To ascertain the set objective, after extraction with ethanol and hexane, the disk and well diffusion agar methods were employed to investigate the antimicrobial activity of the extracts and its minimum inhibitory and bactericidal concentration...

Measurements of aminoglycosides by an agar disk diffusion assay are inhibited by heparin in a dose-dependent way. When assayed by a homogeneous immunoassay, this was only evident for tobramycin. This indicates that specimens for aminoglycoside measurement should not be obtained in heparinized tubes. When heparin is used clinically as an anticoagulant, the amount in blood does not reach levels t...

Fosfomycin may be a treatment option for multiresistant Gram-negative bacteria. This study compared susceptibility methods using 94 multiresistant clinical isolates. With agar dilution (AD), susceptibilities were 81%, 7%, 96%, and 100% (CLSI) and 0%, 0%, 96%, and 30% (EUCAST), respectively, for Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterobacter spp. Categor...