Seven-year evaluation of Stenotrophomonas maltophilia bacteremia in a university-affiliated hospital

Abstract

Introduction: Stenotrophomonas maltophilia is the only opportunistic human pathogen in the genus Stenotrophomonas. These bacteria can be isolated from healthcare settings, possibly resulting in bacterial colonization of medical devices, which cause nosocomial infections. S. maltophilia bacteremia results in high mortality and morbidity. This study aimed to determine the outcomes of S. maltophilia bacteremia and its associated mortality risk factors. Methodology: This was a retrospective study conducted at the University of Medical Sciences, Bakirkoy Dr. Sadi Konuk Training and Research Hospital (Istanbul, Turkey) from December 2015 to December 2022. Medical records, demographic information, clinical conditions, laboratory data, antimicrobial susceptibility, and clinical outcomes were retrospectively analyzed for the period between December 2015 and December 2022. Results: Data from 87 patients (median age 61 years) with bacteremia were included in this study. The most common underlying conditions were diabetes mellitus (DM; 32.2%), hypertension (29.9%), and malignancies (19.5%). The most common sources of bacteremia were central venous catheters (CVCs; 44%), primary blood infection (32%), respiratory tract infection (20.7%), and wound site/abscess infection (2.3%). Seventy-eight percent of the patients were admitted to the intensive care unit (ICU) when bacteremia was detected. The 28-day mortality rate was 55%. The mortality rate was significantly higher in the ICU (p < 0.001). Elevated values of procalcitonin and C-reactive protein, and the presence of CVC were significant risk factors for mortality in those with S. maltophilia bacteremia. Conclusions: S. maltophilia bacteremia should be carefully monitored in patients with CVCs. Timely removal of CVCs can result in decreased mortality.

Keywords

• Stenotrophomonas maltophilia
• bacteremia
• mortality
• risk factors