Risk Factors and Clinical Characteristics of Stenotrophomonas Maltophilia Infections in Neonates

Background: The aim of this study was to review the risk factors and clinical, bacteriological, and epidemiological characteristics of Stenotrophomonas maltophilia infections in our neonatal intensive care unit.

Methods: A retrospective matched case-control study was performed by comparing 23 cases of S maltophilia with 45 controls to identify the potential risk factors. To identify the case patients, the admission and medical records of patients in the neonatal intensive care unit and records from the Microbiology Department were reviewed between 2003 and 2008.

Results: Sepsis in two neonates (9%), conjunctivitis in two neonates (9%), and ventilator-associated pneumonia in 19 (82%) neonates were determined. Invasive-procedures, exposure to aminoglycoside and carbapenem, total parenteral nutrition, histamine 2 blockers, exposure to steroids, cholestasis, and duration of hospitalization were significantly associated with S maltophilia infections (p<0.05). On multivariate analysis, invasive procedures (odds ratio, 18.81) and duration of hospitalization (odds ratio, 1.06) were determined to be the risk factors for S maltophilia infection. The most active antimicrobial agent was trimethoprim/sulfamethoxazole (87%) for S maltophilia infection, and the mortality rate was 17%.

Conclusions: Neonatologists should avoid from unnecessary invasive procedures and broad-spectrum antibiotics to reduce S maltophilia infections. Invasive procedures should be finished in the shortest time possible. Agent/factor-specific antibacterial treatment should be administered. Patients being discharged as early as possible will also reduce infection frequency. Stenotrophomonas maltophilia should be considered in patients with high Stenotrophomonas infection risk factors.