Development of EUCAST disk diffusion method for susceptibility testing of the Bacteroides fragilis group isolates

摘要: With the emergence of antibiotic resistance among Bacteroides fragilis group isolates need susceptibility testing in routine laboratories is increasing. The aims present study were to evaluate disk diffusion method for case different clinical spp by comparing zone diameter results with MICs obtained earlier during an Europe-wide surveillance, and propose breakpoints, which correlate EUCAST MIC breakpoints. We tested 381 B. fragilis amoxicillin/clavulanic acid, cefoxitin, clindamycin, imipenem, metronidazole, moxifloxacin, piperacillin/tazobactam, tigecycline agar dilution previously. inhibition zones same antibiotics including meropenem disc determined on Brucella blood supplemented haemin vitamin K1. Plates incubated at 37 °C anaerobic atmosphere 24 h. diameters read 100% inhibition. In discrepant gradient test compared plate. found a good agreement between moxifloxacin tigecyclin. also separated clearly isolates, can be considered wild-type isolates. acid piperacillin/tazobactam intermediate susceptible according determination, overlap determination. Isolates <23 mm <25 mm should retested determination method. 10 μg clindamycin resistant population strains. cefoxitin only could <17 mm, overlap. conclusion, we suggest that option most relevant laboratories.