Antibiotic Resistance Profile of Stenotrophomonas maltophilia Infections with Limited Antibiotic Options

Objective: Stenotrophomonas maltophilia is an opportunistic pathogen that frequently causes nosocomial infections in recent years. It is generally isolated from respiratory tract samples, blood, urine and drainage materials. Due to multiple antibiotic resistance, a limited number of antibiotics are used in the treatment of these infections. The aim of this study is to investigate the antibiotic resistance status and risk factors in isolated S. maltophilia strains. Method: Diversity and antibiotic susceptibility levels of S. maltophilia strains isolated from various clinical samples between January 2018 and June 2020 were examined using conventional methods and VITEK2 automated system. Demographic and diagnostic data of the patients were retrieved from the hospital’s data base to identify the risk factors of infection. Results: Of the 300 strains examined, 46% were isolated from intensive care units, 35.3% from patients hospitalized in other clinics, and 18.7% from outpatient clinic patients. It was observed that 64 (21.3%) of 300 patients were immunosuppressed. Trimethoprim-sulfamethoxazole resistance was 1.3% and levofloxacin resistance was 0.7%. Conclusion: Resistance rates were found to be lower than the literature data in the study. It was concluded that hospitalization in the intensive care unit and immunosuppression are important risk factors for S. maltophilia infections.