Clinical gradient and predictors for stepwise resistance escalation of carbapenem-susceptible, carbapenem-resistant, and difficult-to-treat resistant Pseudomonas aeruginosa infections: a 6-year retrospective cohort study

Objective

Difficult-to-treat resistant Pseudomonas aeruginosa (DTR-PA) represents the most severe antimicrobial resistance phenotype of P. aeruginosa, with limited therapeutic options and poor clinical outcomes. However, previous studies have largely focused on carbapenem-resistant P. aeruginosa (CRPA), and the factors associated with resistance acquisition and progression remain insufficiently characterized. This study aimed to investigate the clinical characteristics and risk factors associated with different resistance phenotypes of P. aeruginosa from the perspectives of both resistance acquisition and resistance escalation.