Hanli Wang, Min Xing, Haoyu Ji, Yusheng Cheng, Shuhui Hu, Guofeng Wang, Susheng Zhou, Yonghui Han, Bohan Zhang, Lei Zha, Qinghai You
In this cohort of patients with S. maltophilia infection, mortality was associated primarily with host vulnerability and illness severity rather than prior carbapenem exposure or empirical treatment appropriateness alone. Prior carbapenem use may reflect underlying disease complexity rather than act as an independent driver of mortality. These findings suggest that clinical management should emphasize early risk stratification, careful assessment of comorbidity burden, timely supportive care, and antimicrobial selection guided by local susceptibility patterns.
BACKGROUND: Stenotrophomonas maltophilia is an intrinsically multidrug-resistant opportunistic pathogen that causes clinically significant infections, particularly in immunocompromised and critically ill patients. The independent contributions of prior antimicrobial exposure and early active therapy to mortality remain uncertain. This study evaluated clinical characteristics, antimicrobial exposure patterns, empirical treatment appropriateness, and mortality-associated factors in patients with clinically confirmed S. maltophilia infection.
METHODS: This single-center retrospective cohort study included 458 hospitalized patients with confirmed S. maltophilia infection at a tertiary hospital between 1st June 2023 to 31st July 2025. Demographic characteristics, comorbidities, infection-related variables, prior antimicrobial exposure, empirical treatment regimens, laboratory indicators, antimicrobial susceptibility results, and in-hospital outcomes were extracted from electronic medical records. Univariable and multivariable logistic regression analyses were performed to identify factors associated with all-cause in-hospital mortality, with particular attention to prior carbapenem exposure and the appropriateness of initial empirical antimicrobial therapy.
RESULTS: Overall in-hospital mortality was 11.8% (54/458). Compared with survivors, non-survivors were older, had a higher Charlson Comorbidity Index (CCI), and more frequently presented with severe clinical features, including septic shock, mechanical ventilation, central venous catheterization, and elevated inflammatory markers. In the multivariable model, older age and higher CCI remained independently associated with mortality, whereas mechanical ventilation showed a strong but statistically non-significant association. Prior carbapenem exposure was common, but mortality was comparable between carbapenem-exposed and unexposed patients. The appropriateness of initial empirical antimicrobial therapy was not independently associated with survival after adjustment for baseline and severity-related factors. Antimicrobial susceptibility testing showed high in vitro activity for minocycline, cefoperazone/sulbactam, doxycycline, and tigecycline.
CONCLUSIONS: In this cohort of patients with S. maltophilia infection, mortality was associated primarily with host vulnerability and illness severity rather than prior carbapenem exposure or empirical treatment appropriateness alone. Prior carbapenem use may reflect underlying disease complexity rather than act as an independent driver of mortality. These findings suggest that clinical management should emphasize early risk stratification, careful assessment of comorbidity burden, timely supportive care, and antimicrobial selection guided by local susceptibility patterns.