Although recent studies have suggested that some antibacterial agents have good activity against the rapidly growing mycobacteria Mycobacterium fortuitum and Mycobacterium chelonei, an easily applicable method for susceptibility testing of clinical isolates is not yet available. We evaluated a disk diffusion method with Mueller-Hinton agar and 48-h readings with 59 strains of M. fortuitum and 1...

The activity of antimicrobial agents against Fusobacterium species has been reported as variable in the literature. For some strains, the inconsistency arises from difficulty in determining the endpoint of growth in agar dilution susceptibility tests. Certain strains persist as a subtle haze beyond the levels of antibiotic that permit conventional colonial growth. We have determined by light an...

There are currently no standardized phenotypic methods for the screening and detection of AmpC enzymes. This study aimed to evaluate different methods to detect AmpC enzymes in Escherichia coli, Klebsiella spp., and Proteus spp., comparing the results from two disk-based methods and an agar dilution method. AmpC activity was determined for 255 clinical isolates by use of a three-dimensional enz...

MICs of isoniazid, rifampin, ethionamide, streptomycin, amikacin, kanamycin, and capreomycin were determined for Mycobacterium avium complex strains by two methods: broth dilution in 7H12 medium radiometrically and agar dilution on 7H10 agar plates. The broth-determined MICs of all drugs with the exception of isoniazid were two to eight times lower than the agar-determined MICs for most of the ...

Semiautomated rapid broth elution (Autobac Multi-Test System; General Diagnostics, Div. Warner-Lambert Co., Morris Plains, N.J.) and disk diffusion tests were compared with an agar dilution breakpoint method to determine the antibiotic susceptibility of 147 methicillin-resistant Staphylococcus aureus isolates from our hospital. Although the disk diffusion method, in general, correlated well wit...

OBJECTIVE The main objective of this study was to comparatively evaluate the performance of M.I.C.E. and Etest methodologies to that of agar dilution for determining the antimicrobial susceptibility profile of oxacillin-resistant Staphylococcus spp. METHODS A total of 100 oxacillin-resistant Staphylococcus spp. isolates were collected from hospitalized patients at a teaching hospital. Antimic...

Norfloxacin, a new quinoline derivative, was studied in vitro, and determinations of agar dilution minimal inhibitory concentrations (MICs) and broth dilution MICs and MBCs were made. Nalidixic acid and cinoxacin were used as comparative agents. Norfloxacin was found to be extremely active against all strains tested of Escherichia coli, Klebsiella spp., Proteus mirabilis, indole-positive Proteu...

Gonococcal (GC) agar supplemented with glucose and glutamine was found to be superior to Eugonagar and Trypticase soy agar in demonstrating the hemin requirement of 23 strains of Haemophilus ducreyi by the satellite growth test. The porphyrin test confirmed the requirement for exogenous hematin. With the agar dilution technique, using supplemented GC agar, the hemin concentration required to in...