Recently, multi-drug resistant nosocomial pathogens have become an important problem in hospitals. The most frequently isolated Gram negative bacilli from blood specimens are Escherichia coli, Klebsiella pneumoniae and Enterobacter species. In this study 80 E. coli, 45 K. pneumoniae and 25 Enterobacter spp. blood isolates of hospitalized patients which were sent to our laboratory between January 2004 and January 2005 were examined for their susceptibilities to some antimicrobial agents by Kirby-Bauer disk diffusion method according to NCCLS standards.

While the most effective antibiotic against all tested bacteria was imipenem, the less effective one was amoxicillin/clavulanic acid. Although the resistance patterns of all bacteria were similar, higher resistance rates were determined among K. spneumoniae and Enterobacter strains especially against ceftazidime, and cefoxitin.