The effect of hypoxic conditions on the in vitro efficacy of amphotericin B and posaconazole against Mucorales was evaluated by defining MICs with Etest and broth microdilution and identifying minimal fungicidal concentrations (MFCs). With Etest, oxygen-dependent changes were detected, while the MIC and the MFC determined with broth microdilution remained unaltered with reduced oxygen levels. T...

Two hundred and fifty tracheal aspirates were subjected to direct antimicrobial susceptibility testing by disk diffusion, Etest and inoculation on antibiotic-enriched MacConkey agar plates. Results were compared with those obtained using an automated system on microorganisms recovered from standard quantitative culture. A total of 255 microorganisms were isolated from 194 positive samples by th...

We performed Etest and broth microdilution (BMD) susceptibility testing of caspofungin, micafungin and anidulafungin against 67 clinical isolates of Aspergillus spp. and 10 Fusarium spp. Minimal effective concentrations (MECs) by BMD were read after 24 h of incubation at 35 degrees C and Etest MICs were read at 24 and 48 h. MECs < or =0.25 mg/l were obtained with caspofungin for all Aspergillus...

Inhaled administration of tobramycin assures high concentrations in cystic fibrotic lungs, improving the therapeutic ratio over that of parenteral tobramycin levels, particularly against Pseudomonas aeruginosa. Conventional Clinical and Laboratory Standards Institute (CLSI; formerly National Committee for Clinical Laboratory Standards) breakpoints only consider parenteral levels and do not take...

OBJECTIVE Iso-Sensitest agar (ISA), which is recommended by the BSAC for routine susceptibility testing of staphylococci and enterococci, contains insufficient calcium for testing daptomycin. Isotonic agar supplemented with 50 mg/L calcium has been advocated, but is not routinely available in many laboratories. We evaluated a daptomycin Etest that incorporates a constant level of calcium throug...

The caspofungin susceptibilities of 28 Candida sp. clinical isolates, including 8 caspofungin-resistant isolates characterized by mutations in the Fks1 protein, were determined by the Etest in RPMI and AM3 media. Good discrimination between wild-type and mutant isolates was obtained. These results suggest that the Etest is valuable for the detection of caspofungin resistance in Candida spp.

MICs of daptomycin, linezolid, and vancomycin against 212 isolates, including Listeria monocytogenes and Pediococcus, Leuconostoc, Rhodococcus, and Nocardia spp., were determined by the broth microdilution method; daptomycin MICs were also determined by the Etest. Except with those for Leuconostoc spp., daptomycin Etest MICs showed >90% agreement with MICs obtained by the broth microdilution me...

MICs of antibiotics against Bilophila wadsworthia isolates were measured by agar and broth microdilution with pyruvic acid and by Etest. The inoculum size influenced greatly agar dilution. Despite discrepancies in MICs depending on the measurement method used, clindamycin consistently showed potent activity. Broth microdilution and Etest appear to be candidates for laboratory susceptibility tes...

Vancomycin and daptomycin MICs from 161 isolates of methicillin-resistant Staphylococcus aureus (MRSA) were compared using commercial and in-house broth microdilution, Etest, and common automated methods. Vancomycin Etest MICs were higher than those of other methods, whereas the MICs for daptomycin testing were comparable. Vancomycin MICs vary depending on the testing methodology.

Glycopeptide-intermediate Staphylococcus aureus (GISA) and, in particular, heterogeneous GISA (hGISA) are difficult to detect by standard MIC methods, and thus, an accurate detection method for clinical practice and surveillances is needed. Two prototype Etest strips designed for hGISA/GISA resistance detection (GRD) were evaluated using a worldwide collection of hGISA/GISA strains covering the...