Clinical predictors of Pseudomonas aeruginosa or Acinetobacter baumannii bacteremia in patients admitted to the ED

Abstract The identification of clinical characteristics that could identify patients at high risk for Pseudomonas aeruginosa or Acinetobacter baumannii bacteremia would aid clinicians in the appropriate management of these life-threatening conditions, especially in patients admitted to the emergency department (ED) with community-onset infections. To determine clinical risk factors for P aeruginosa or A baumannii bacteremia in patients with community-onset gram-negative bacteremia (GNB), a post hoc analysis of a nationwide bacteremia surveillance database including patients with microbiologically documented GNB was performed. Ninety-six patients with P aeruginosa or A baumannii bacteremia were compared with 1230 patients with Escherichia coli or Klebsiella pneumoniae bacteremia. A solid tumor or hematologic malignancy was more likely to be associated with P aeruginosa or A baumannii bacteremia, whereas concurrent neurologic disease was less frequently seen. In regards to the site of infection, pneumonia was more common in P aeruginosa or A baumannii bacteremia, whereas a urinary tract infection was less frequently seen. Factors associated with P aeruginosa or A baumannii bacteremia in multivariate analysis included pneumonia (odds ratio [OR], 3.60; 95% confidence interval [CI], 1.86-6.99), hematologic malignancy (OR, 2.71; 95% CI, 1.26-5.84), male sex (OR, 2.17; 95% CI, 1.31-3.58), solid tumor (OR, 1.89; 95% CI, 1.15-3.12), and health-care–associated infection (OR, 1.88; 95% CI, 1.48-2.41). Our data suggest that an initial empirical antimicrobial coverage of P aeruginosa or A baumannii bacteremia should be seriously considered in patients with pneumonia, a hematologic malignancy, solid tumor, or health-care–associated infection, when GNB is suspected, even in community-onset infections.