Impact of pathophysiologically relevant underlying disease burden on pathogen distribution and antimicrobial...

To investigate the impact of pathophysiologically relevant underlying disease burden on the distribution of pathogenic bacteria and antimicrobial resistance in patients with device-associated urinary tract infections (DA-UTIs), and to provide evidence for precise empirical therapy and infection prevention and control in high-risk populations.

Only underlying diseases with known pathophysiological relevance to urinary tract infection (e.g., diabetes mellitus, urinary stones/obstruction, renal insufficiency, etc.) were considered. A retrospective study was conducted on 449 patients with DA-UTIs admitted to the Affiliated Hospital of Xuzhou Medical University from January 2020 to December 2024. Patients were stratified into three groups according to the number of underlying diseases: Group A (no underlying diseases), Group B (one underlying disease), and Group C (≥2 underlying diseases). Clinical manifestations and pathogenic spectrum composition were compared among the three groups, and the antimicrobial resistance characteristics of Escherichia coli and Klebsiella pneumoniae were analyzed.

The median age of the patients was 66 years, and most patients were admitted to the Department of Urology and Intensive Care Unit (ICU). Escherichia coli was the predominant pathogen (41.6%), and the isolation rate of Candida species showed an increasing trend with the aggravation of underlying disease burden. Antimicrobial resistance analysis revealed a significant correlation between underlying disease burden and the resistance of Escherichia coli to fluoroquinolones: Group C had a significantly increased risk of ciprofloxacin resistance (P = 0.009), while Group B had a higher resistance risk to levofloxacin (P = 0.018) and norfloxacin (P = 0.019). For Klebsiella pneumoniae, the resistance risks to cefotetan (P = 0.029), doripenem (P = 0.036), and amikacin (P = 0.026) were significantly elevated in Group B. Carbapenems, aminoglycosides, and polymyxins maintained high susceptibility across all groups.

In patients with DA-UTIs, pathophysiologically relevant underlying disease burden is closely associated with antimicrobial resistance of pathogenic bacteria, particularly significantly increasing the risk of fluoroquinolone resistance. Routine use of fluoroquinolones should be avoided in such high-risk patients for clinical empirical therapy. The initial treatment regimen should be optimized and etiological testing should be strengthened based on local antimicrobial resistance surveillance data and the patient's comorbidity status.