Predictors of mortality of Pseudomonas aeruginosa bacteraemia and the role of infectious diseases consultation and source control; a retrospective cohort study.

Abstract

To determine predictors of mortality among patients with Pseudomonas aeruginosa bacteraemia. Retrospective study. This study conducted at the Lausanne University Hospital, Switzerland included adult patients with P. aeruginosa bacteraemia from 2015 to 2021. During the study period, 278 episodes of P. aeruginosa bacteraemia were included. Twenty (7%) isolates were multidrug-resistant. The most common type of infection was low respiratory tract infection (58 episodes; 21%). Sepsis was present in the majority of episodes (152; 55%). Infectious diseases consultation within 48h of bacteraemia onset was performed in 203 (73%) episodes. Appropriate antimicrobial treatment was administered within 48h in 257 (92%) episodes. For most episodes (145; 52%), source control was considered necessary, with 93 (64%) of them undergoing such interventions within 48h. The 14-day mortality was 15% (42 episodes). The Cox multivariable regression model showed that 14-day mortality was associated with sepsis (P 0.002; aHR 6.58, CI 1.95-22.16), and lower respiratory tract infection (P < 0.001; aHR 4.63, CI 1.78-12.06). Conversely, interventions performed within 48h of bacteraemia onset, such as infectious diseases consultation (P 0.036; HR 0.51, CI 0.27-0.96), and source control (P 0.009; aHR 0.17, CI 0.47-0.64) were associated with improved outcome. Our findings underscore the pivotal role of early infectious diseases consultation in recommending source control interventions and guiding antimicrobial treatment for patients with P. aeruginosa bacteraemia.