The determination of resistance to ertapenem and other antibiotics with ESBL product of Enterobacteriaceae isolated from urine samples

Objective: Enterobacteriaceae is the most frequently isolated bacteria in urinary system infections. This study investigated the antibiotic susceptibility including ertapenem and extended-spectrum beta-lactamase production of bacteria belons to Enterobacteriaceae isolated from the urinary culture. Methods: Enterobacteriaceae strains, identified by using conventional methods in our laboratory between January 2012 and March 2012, were included the study. The antibiotic susceptibilities were investigated with the KirbyBauer disc diffusion method and the ESBL productions were examined with the double-disc synergy method in accordance with the suggestions of Clinical and Laboratory Standards Institute. Results: In the study, a total of 148 strains were isolated (117 E.coli, 23 Klebsiella spp. and 4 Proteus spp. and 4 Enterobacter spp.). While 26 of E.coli strains (22%), and 8 of Klebsiella spp. strains (35%) were considered ESBL positive, no ESBL production was determined for Proteus spp. and Enterobacter spp. strains. All the isolated strains were found to be susceptible to ertapenem and meropenem. Amikacin, piperacillin-tazobactam and cefoxitin were determined to be other antibiotics with the greatest effect on Enterobacteriaceae species. Conclusion: Ertapenem was observed to be alternative in the treatment of Enterobacteriaceae isolated from the urinary culture. Carbapenems in particular, amikacin, piperacillin-tazobactam and cefoxitin were found to be the most effective antibiotics in the treatment of this infection.