An evaluation of six-year Stenotrophomonas maltophilia   infections in a university hospital

Background: Stenotrophomonas maltophilia is a Gram-negative bacillus and opportunistic emergent pathogen causing hospital-acquired infections (HAIs). Due to risk factors such as prolonged intensive care unit stay and invasive procedures, it has become one of the leading causes of HAIs.
Objective: The aim of this study was to evaluate the epidemiology of S.maltophilia infections over a six-year period at Düzce University Hospital, Turkey.
Methods: The incidence, clinical characteristics, antimicrobial susceptibility and outcomes of nosocomial S. maltophilia infections during this period were retrospectively analyzed.
Results: During the study period, 67 samples obtained from 61 patients were identified. Pneumonias (82%) were the most common HAIs, followed by bloodstream infections (10.5%), urinary tract infections (3%), skin and soft tissue infections (3%) and surgical site infection (1.5%). Admission to intensive care, hospitalization exceeding 30 days, and previous use of broad-spectrum antibiotics constituted risk factors. Resistance to cotrimoxazole (6%) was lower than that to levofloxacin (18%).
Conclusion: The most important risk factors for S.maltophilia infection in patients are previous exposure to antibiotics, prolonged hospitalization and invasive procedures such as mechanic ventilation. Discharging patients as early as possible with the rational use of antibiotics may be effective in reducing S. maltophilia infections and resistance rates.

Keywords
Stenotrophomonas maltophilia; hospital-acquired infections; epidemiology; risk factors.