Hospital Infections by Stenotrophomonas maltophilia: Results in Five Years of Multicentric Study

Background: Stenotrophomonas maltophilia is an emerging pathogen responsible for high morbidity and mortality rates. Hospital infections caused by this bacteria, especially in intensive care centers, are concerning for the health system, given that the microorganism is multidrug resistant to most antimicrobials available. Objective: Therefore, the present study is built from an analysis of the variables related to nosocomial infections caused by S. maltophilia in hospitals in Brazil, to display points of major concern. Methods: We used the data collected by the Infection Prevention and Control Service to clarify the incidence rate of Stenotrophomonas maltophilia in Brazilian hospitals as well as the gross lethality of these infections and the profiles of infected patients. We collected and analyzed epidemiological data from 10 hospitals in Brazil for the period July 2014 to June 2019 according to the CDC NHSN protocol. Results: In 5 years, 93 Stenotrophomonas maltophilia infections were diagnosed in the hospitals analyzed. Overall, 61 occurred in men (66%) and 32 occurred in women (34%). Furthermore, 47 cases (51%) occurred in adult ICUs; 19 cases (20%) followed zascular surgery; 9 (10%) cases occurred in the neonatal ICU; 7 (8%) cases were from the medical clinic; and 11 (12%) were from other clinics. The incidence rate was 1.2 cases for 10,000 hospitalizations, ranging from 0.0 to 2.8 (Fig. 1). Patients’ ages ranged from 0 to 90 years, with a mean of 55 years (SD, 26 years) and a median of 64 years. Time between admission and diagnosis of infection was 1 to 102 days, with a mean of 24 days (SD, 21 days) and a median of 17 days. The gross lethality for S. maltophilia infection was 43 of 93 (46%) (95% CI, 35.8%–56.9%). The frequencies of specific infections were as follows (Fig. 2): pneumonia, 26 (28%); tracheobronchitism, 22 (24%); primary bloodstream infection, 18 (19%); skin and soft-tissue infection, 13 (14%); local infection, 7 (8%); vascular access infection, 3 (3%); urinary tract infection, 2 (2%); gastrointestinal infection, 1 (1%); and eye, nose, throat, and mouth infections, 1 (1%). Conclusions:Stenotrophomonas maltophilia infection is a rare and highly lethal event that usually occurs after 2 weeks of hospitalization. The most affected region is the respiratory tract, with a higher incidence in patients aged >60 years or in the ICU. Early and accurate investigations of multiresistant microorganisms in a hospital setting are needed to reduce patient morbidity and mortality. Funding: None Disclosures: None