Investigation of Fosfomycin Susceptibility in Extended Spectrum Beta-Lactamase Producing Enteric Bacteria by Disk Diffusion, Automated System and Agar Dil ütion Kit

In this study, it was aimed to evaluate the utility of disk diffusion, agar dilution kit and automated MicroScan methods (Beckman Coulter, Brea, CA, ABD) for fosfomycin susceptibility of ESBL-producing enteric bacteria. The study included 120 ESBL positive isolates of enteric bacteria (89 Escherichia coli, 31 Klebsiella pneumoniae) cultivated from the samples sent to the Microbiology Laboratory of the Mersin University Medical Faculty of Medicine Hospital between May 2019 and November 2019. Fosfomycin susceptibilities of the isolates included in the study were tested by disk diffusion, automated MicroScan and the commercial agar dilution kit. In the study, 37 (30.8%) of 120 isolates were determined as resistant to fosfomycin by disk diffusion method and six (5%) of the isolates were found to be resistant to fosfomycin with the MicroScan automatized system. With the agar dilution kit, 11 (9.1%) of 120 isolates were found to be resistant as the minimum inhibitory concentration (MIC) values were > 32 µg/ml. Fosfomycin resistance was significantly higher in K.pneumoniae isolates than E.coli isolates by agar dilution method (p= 0.006). Ertapenem resistance was detected in seven of 120 isolates. All seven isolates that were resistant to ertapenem were susceptible to fosfomycin by agar dilution method. All three isolates, which were found resistant to colistin, were susceptible to fosfomycin by agar dilution method. In the study, the categorical agreement of the disk diffusion a...
Source: Mikrobiyoloji Bulteni - Category: Microbiology Authors: Source Type: research