Long-Term Outcomes of Multidrug-Resistant Pseudomonas aeruginosa Bacteriuria: A Retrospective Cohort Study

Abstract

The relationship between bacteriuria and subsequent symptomatic infections, particularly bacteraemia, has been a subject of ongoing research. We aim to investigate the clinical characteristics, long-term outcomes, and factors associated with subsequent symptomatic infection following an initial multidrug-resistant P. aeruginosa (MDRP) bacteriuria episode. A retrospective cohort study was conducted among patients with MDRP bacteriuria who were hospitalized at a tertiary care hospital from 2009 to 2018, with a 12-month follow-up period for each patient. The primary endpoint was the incidence of subsequent symptomatic MDRP infections at any site, and the secondary endpoint was the overall mortality rate. A total of 260 patients with MDRP bacteriuria were included in the analysis, of whom 155 patients (59.6%) had asymptomatic bacteriuria. Subsequent symptomatic MDRP infections were documented in 79 patients (30.3%) within 12 months of the initial bacteriuria episode: UTI (n = 47, 18.1%), pneumonia (n = 21, 8.1%), bacteraemia (n = 9, 3.5%), soft tissue infection (n = 7, 2.7%), and bone and joint infection (n = 4, 1.5%). Intensive care unit (ICU) acquisition and recurrent bacteriuria were independent risk factors of subsequent symptomatic infections in patients with MDRP bacteriuria. The overall mortality rate was 16.9%, with 31.8% of deaths estimated to be associated with MDRP infection. Solid tumours, cardiovascular diseases, chronic liver disease, chronic lung disease, ICU acquisition, absence of pyuria, and concurrent MDRP bacteraemia were independent predictors of mortality. MDRP bacteriuria has the potential for progression to symptomatic infection and associated mortality. Targeted interventions and prevention strategies were crucial to reduce subsequent infections in patients with MDRP bacteriuria, especially in high-risk patients.