Objective: The aim of this study is to identify nonfermentative gram negative bacteria isolated in Intensive Care Unit patients and antibiotic resistance patterns of these agents. The aim of this study is retrospective evaluation of the frequency of isolation and antimicrobial resistance patterns of 474 nonfermentative gram negative bacteria isolated from clinical materials sent from patients hospitalized in the Intensive Care Units of Ondokuz Mayıs University Medical Faculty Hospital, between January 2014 and December 2015.

Material and Method: Identification and antimicrobial susceptibility of the bacteria were performed in Vitek MS and Vitek2 Compact systems, respectively.

Results: The most frequently isolated bacteria in clinical specimens sent from Intensive Care Units was Acinetobacter spp. (69.83%) followed by Pseudomonas aeruginosa (25.52%) and Stenotrophomonas maltophilia (4.64%). Bacteria were most frequently isolated from tracheal aspirates (40.71%). Acinetobacter spp. and P. aeruginosa isolates have the highest susceptibility to colistin, and susceptibility of S. maltophilia isolates to trimethoprim/ sulfamethoxazol (SXT) was determined as 95.4%.

Conclusion: Effective infection control measures and active survelliance are important measures for prevention of infections in intensive care units.