Risk Factors and Outcomes of Patients with Carbapenem-Resistant Pseudomonas aeruginosa Bloodstream Infection

Purpose: The rising incidence of carbapenem-resistant Pseudomonas aeruginosa (PA) bloodstream infection (BSI) has made the selection of antibiotic therapy more difficult and caused high mortality. This study was aimed at exploring the risk factors for carbapenem-resistant Pseudomonas aeruginosa (CRPA) bloodstream infection and identifying the risk factors for the outcomes of patients with PA-BSI.

Methods: We performed a retrospective cohort study of patients with PA-BSI in a tertiary hospital from January 2017 to December 2021 in China. Epidemiological, clinical, and microbiological characteristics were described. Risk factors for CRPA-BSI and the outcomes of PA-BSI inpatients were identified, using multivariate logistic regression analysis.

Results: A total of 198 PA-BSI inpatients were included. The negative outcome rate was significantly higher in patients infected with CRPA (15/34, 44.12%) than with carbapenem-susceptible Pseudomonas aeruginosa (CSPA) (35/164, 21.34%), and the difference was statistically significant (P=0.005). Multivariate logistic regression analysis showed that previous exposure to carbapenem (OR 3.519, 95% CI 1.359-9.110, P=0.010) was an independent risk factor for CRPA-BSI. In addition, CRPA (OR 1.615, 95% CI 0.626-4.171, P=0.32) was not an independent risk factor for negative outcome among PA-BSI inpatients.

Conclusion: Our study showed that previous exposure to carbapenem was an independent risk factor for CRPA-BSI. CRPA was not an independent risk factor for a negative outcome in PA-BSI inpatients.