Investigation of extended spectrum beta lactamases in e.coli and klebsiella spp. strains by 3 different methods

Investigation of expanded-spectrum beta-lactamases in E. coli K. pneumoniae strains by different methods Objective: Combined Disc Method, Double Disc Synergy Method and Three Disc Dimensional Testing Methods Materials and Methods: Three methods were applied to 125 E. coli and 25 K. pneumoniae strains isolated from patients. Strains were identified at the species level by conventional methods. ESBL production by double disc synergy method was 85 (68.00%) for 125 E. coli isolates and 9 (76.00%) for 25 K. pneumoniae isolates, 105 (84%, 125 isolates for E. coli with three-dimensional test). 00) 17 (68.00%) of 25 isolates for K. pneumoniae, 77 (61.60%) of 125 isolates for E. coli and 17 (68.00%) for K. pneumoniae were detected by combined disc diffusion method. . Detection of ESBL by phenotypic methods due to different resistance genes in Enterobacteriaceae strains often leads to wrong results. In our study, the three-dimensional test for E. coli isolates and the double disc synergy method for K. pneumoniae isolates were found to be the highest ESBL detection methods. According to the results of our study, it is suggested that molecular and phenotypic tests should be combined. The most effective method to investigate ESBL in centers that do not meet the requirements of E. coli for the three-dimensional test, K. pneumoniae double disc synergy test should be applied.