Antipseudomonal cephalosporins versus piperacillin/tazobactam or carbapenems for the definitive antibiotic treatment of Pseudomonas aeruginosa bacteraemia: new kids on the ICU block?

This article focuses on a multicentre retrospective study conducted in 14 Italian hospitals to identify predictors of 30-day mortality and evaluate the effectiveness of different antibiotic regimens for Pseudomonas aeruginosa bloodstream infections (Pa-BSIs) in intensive care units (ICUs). Among 170 ICU patients with Pa-BSIs, independent predictors of mortality included higher Charlson comorbidity index, neutropenia, septic shock, and high-risk infection sources, while previous colonization by P. aeruginosa and use of antipseudomonal cephalosporins (ceftolozane/tazobactam, ceftazidime/avibactam, cefiderocol) were protective factors. After adjustment for treatment biases, only antipseudomonal cephalosporins maintained a significant association with reduced mortality, whereas combination therapy showed benefit primarily in patients with septic shock. The study suggests that antipseudomonal cephalosporins may be preferred definitive therapies for Pa-BSIs in ICU settings, with initial combination therapy considered for severe cases involving septic shock.