Abstract
Introduction: This study aims to investigate the antibiotic resistance of the agents isolated from cerebrospinal fluid (CSF) samples of adult patients in our hospital for five years to contribute to surveillance data.
Materials and Methods: 121 CSF samples were included in the study between January 2015 and January 2020. Identification of isolates and determination of antibiotic susceptibility profile was performed according to EUCAST criteria with VITEK 2 (bioMérieux, France) automated system.
Results: Microorganisms (n=39) were isolated in 37 (30.6%) 121 cerebrospinal fluid cultures. The most frequently isolated agent is coagulase-negative staphylococci (CNS) by 30.8%. It is followed by Micrococcus spp (%15.4), Streptococcus pneumoniae (%10.3), Klebsiella pneumoniae (%10.3), Acinetobacter baumanii (%10.3), S. aureus (%5.1) and Corynebacterium spp (%5.1). 29 (74.4%) of the agents were isolated from hospitalized patients and 10 (25.6%) outpatients. Oxacillin resistance was found at 83.3% in CNS, and penicillin resistance was found at 25% in Streptococcus pneumoniae. Antibiotics to which K. pneumoniae and A.baumannii isolates are most sensitive are tigecycline and amikacin, respectively.
Conclusion: Different regions and patient populations might cause differences in isolated agents and antimicrobial susceptibility. Retrospective analysis of regional data will assist the clinician in treating patients diagnosed with meningitis, where empirical and agent-oriented therapy is vital.

Key words: Cerebrospinal fluid, antibiotic resistance, bacterial meningitis