Unraveling the complexity of Stenotrophomonas maltophilia – a comprehensive review of current knowledge

Abstract

Abstract Stenotrophomonas maltophilia is a Gram-negative (G−) opportunistic pathogen, prevalent and concerning for susceptible patients. It primarily causes nosocomial and some community-acquired respiratory and bloodstream infections. Reservoirs include water, plant rhizospheres, food, and animals. Virulence factors include motility, biofilm formation, and quorum sensing, with ongoing research on these mechanisms. A major concern is its multidrug resistance to antimicrobial agents like trimethoprim-sulfamethoxazole (TMP-SMX), β-lactams, macrolides, fluoroquinolones, aminoglycosides, chloramphenicol, tetracyclines, and polymyxins. Effective treatments include TMP-SMX, quinolones, penicillins, and penicillins with β-lactamase inhibitors. Rapid diagnosis is crucial for successful treatment, leading to the development of new detection methods such as selective steno medium agar (SMA) and molecular techniques for nucleic acid detection. Patients with S. maltophilia are prone to co-infections with other G− bacteria. A study by Safdar et al. on cancer patients from 1986 to 2002 showed an increase in S. maltophilia infections from 2% to 7%, making it the 5th most commonly isolated G-bacterium in this group. It commonly infects ICU patients and individuals with SARS-CoV-2, with pneumonia being the most frequent clinical manifestation. The COVID-19 pandemic increased intensive care unit admissions and mechanical ventilation use, leading to higher infection rates of S. maltophilia.