The Burden of Bloodstream Infections due to Stenotrophomonas Maltophilia in the United States: A Large, Retrospective Database Study

Bin Cai; Glenn Tillotson; Darrin Benjumea; Patrick Callahan; Roger Echols

doi:10.1093/ofid/ofaa141

The Burden of Bloodstream Infections due to Stenotrophomonas Maltophilia in the United States: A Large, Retrospective Database Study

Open Forum Infect Dis. 2020 Apr 22;7(5):ofaa141. doi: 10.1093/ofid/ofaa141. eCollection 2020 May.

Authors

Bin Cai¹, Glenn Tillotson², Darrin Benjumea³, Patrick Callahan³, Roger Echols⁴

Affiliations

¹ Shionogi Inc., Florham Park, New Jersey, USA.
² GST Micro, Richmond, Virginia, USA.
³ Genesis Research LLC, Hoboken, New Jersey, USA.
⁴ Infectious Disease Drug Development Consulting LLC, Easton, Connecticut, USA.

Abstract

Background: Stenotrophomonas maltophilia is an opportunistic pathogen observed in both nosocomial and community-onset infections. S. maltophilia is intrinsically resistant to many currently available broad-spectrum antibiotics and is often not included in antimicrobial resistance surveillance studies or stewardship programs' guidelines.

Methods: A retrospective cohort study of patients with S. maltophilia bloodstream infection (BSI) in the United States was conducted using the 2010-2015 US Premier Healthcare Database. This study described patient characteristics, infection characteristics, antibiotic treatment, and discharge status.

Results: S. maltophilia was the most common carbapenem-resistant, gram-negative pathogen causing BSIs in this database. Of 486 unique patients with S. maltophilia BSI, 44.6% were assessed as community-onset, 95% of cultures were susceptible to trimethoprim-sulfamethoxazole (TMP-SMX), and 84% were susceptible to fluoroquinolones; 39.1% of patients received a potentially effective antibiotic (fluoroquinolone, doxycycline, ceftazidime, minocycline, or TMP-SMX) during the empiric treatment period (≤3 days post-index culture date), whereas 85.8% received a potential effective antibiotics during the definitive treatment period. The most common antibiotic received as definitive treatment was levofloxacin (48.9%). TMP-SMX was used infrequently empirically (10.5%) and in 38.3% during the definitive period. Compared with BSIs caused by other carbapenem-resistant gram-negative pathogens, S. maltophilia BSIs were more likely to be community-onset, and were more likely to be discharged to home and to have a lower mortality rate.

Conclusions: This study demonstrated that patients at risk for S. maltophilia BSI are highly variable and that standard of care is not clearly defined, leading to questions regarding the appropriateness of antibiotic treatment among patients. Further efforts are needed to better recognize and treat S. maltophilia BSI.

Keywords: Stenotrophomonas maltophilia; antibiotic treatment; bloodstream infection; carbapenem-resistant.