Abstract
Objective: The aim of this study was to determine the enterococci species and antimicrobial resistance rates of enteroccus strains isolated from blood cultures of inpatients.
Materials and Methods: One hundred five Enterococcus spp. strains isolated from blood cultures sent from clinics at Osmaniye State Hospital Microbiology Laboratory between January 2011-December 2013 were included. The isolates were identified by conventional methods and Vitek 2 automated system. Antibiotic susceptibility tests were performed by disk-diffusion method and E-test. Statistical analysis was performed using chi-square test.
Results: Enterococcus spp. strains evaluated, 54(51.4%) were identified as E.faecalis and 51(48.6%) as E.faecium. General Intensive Care Unit(GICU) is the section where most frequently isolated species of both enterococci. Other clinics were Dialysis unit, and Internal Medicine clinics. E.faecium strains were found to be resistant to ampicillin, erythromycin, ciprofloxacin. Resistance rates of E.faecalis strains against ampicillin, erythromycin, ciprofloxacin were 47%, 70.5%, 11.8%, respectively. High-level resistance to gentamicin and streptomycin were determined in 55.6%, 83.3% of E.faecium strains and in 23.5%, 11.8% of E.faecalis strains, respectively (p≤0.05). Two of E.faecium strains and 1 of E.faecalis from GICU were found to be resistant to teicoplanin and vancomycin. Linezolid was found most effective drug and resistance wasn’t determined in none of the strains.
Conclusions: Three vancomycin and teicoplanin resistant strains isolated from blood cultures in our hospital show that the isolates mentioned above may cause significant problems in the future. In addition, linezolid may be a good alternative for the treatment of the resistant enterococcal infections in our hospital.

Key words: Blood culture, Enterococcus facium, Enterococcus faecalis, antibiotic susceptibility, E-test, disk diffusion