The activities of ampicillin, ampicillin-sulbactam, amoxicillin, amoxicillin-clavulanic acid, ticarcillin, ticarcillin-clavulanic acid, piperacillin, piperacillin-tazobactam, aztreonam, and aztreonam-clavulanic against Stenotrophomonas maltophilia strains for which the MICs of penicillins and commercially available b-lactam– b-lactamase inhibitor combinations were higher than the breakpoints us...

Brucella broth without supplementation is the recommended medium for broth microdilution susceptibility tests of Brucella abortus, B. melitensis, and B. suis. Based on an eight-laboratory collaborative study using a pH-adjusted modification of this medium, we propose MIC quality control ranges for three control strains against 10 antimicrobials that are potentially efficacious for treating infe...

A multilaboratory study was undertaken to determine the accuracy of the current National Committee for Clinical Laboratory Standards (NCCLS) oxacillin breakpoints for broth microdilution and disk diffusion testing of coagulase-negative staphylococci (CoNS) by using a PCR assay for mecA as the reference method. Fifty well-characterized strains of CoNS were tested for oxacillin susceptibility by ...

Rosa damascena is referred to as the queen of roses due its ornamental, flavoring, and perfuming uses, along with recognized use in therapy. This study aimed investigate total phenols flavonoids contents, phenolic compounds, antioxidant antibacterial properties hydroethanolic extract from flowers, collected Middle Atlas Morocco (Khenifra). The were assessed using gallic acid quercetin standards...

For broth microdilution susceptibility tests of Francisella tularensis, Mueller-Hinton broth with 2% Isovitalex is recommended. Using that medium, we studied three standard control strains tested with nine antimicrobial agents potentially efficacious for treating tularemia. An eight-laboratory collaborative study generated the data needed to propose appropriate MIC control limits.

The in vitro inhibitory activity of trimethoprim-sulfamethoxazole is inversely related to the amount of thymine and thymidine in the test medium; manufacturers must adequately control their media to avoid spurious antimicrobial susceptibility results. No differences were observed when commercial Mueller-Hinton broth and agar were compared with a semisynthetic broth medium by the use of microdil...

With rapid emergence of multidrug-resistant bacteria, there is often a need to perform susceptibility testing for less commonly used or newer antimicrobial agents. Such testing can often be performed only by using labor-intensive, manual dilution methods and lies outside the capacity of most clinical labs, necessitating reference laboratory testing and thereby delaying the availability of susce...