Objective: Non-fermentative gram- negative bacteria are detected as agents of serious nosocomial infections. The aim of this study is to determine the distribution of nonfermentative gram-negative bacteria isolated from blood cultures and their antibiotic susceptibility rates.

Material and Methods: In our study, susceptibilities to various antibiotics of 134 Acinetobacter baumannii, 77 Pseudomonas aeruginosa, 9 Stenotrophomonas maltophilia and 2 Burkholderia cepacia strains, which were isolated from blood cultures between January 2010 and December 2016, were retrospectively evaluated. Identification and antimicrobial susceptibilities of the detected bacteria were carried out using the VITEK 2 (bioMérieux, France) automated system. Test results between 2010 and 2015 were evaluated according to the CLSI (Clinical and Laboratory Standards Institute) criteria. However in 2016, they were evaluated according to EUCAST (European Committee on Antimicrobial Susceptibility Testing) criteria.

Results: The highest susceptibility rates of A. baumannii strains isolated were determined for colistin (97%). The highest susceptibility rates of P. aeruginosa strains were determined for colistin (97.4%), gentamicin (90.9%) and ceftazidime (88.3%) Colistin was determined as the most effective antibiotic against A. baumannii and P. aeruginosa strains.

Conclusion: For these infections with high morbidity and mortality, similar susceptibility studies should be performed at certain intervals at every center and the results of blood cultures should be reported to the clinics rapidly.