title: Bacterial and clinical characteristics of health care- and community-acquired bloodstream infections due to Pseudomonas aeruginosa.
abstract: Health care-associated infections, including Pseudomonas aeruginosa bloodstream infection, have been linked to delays in appropriate antibiotic therapy and an increased mortality rate. The objective of this study was to evaluate intrinsic virulence, bacterial resistance, and clinical outcomes of health care-associated bloodstream infections (HCABSIs) in comparison with those of community-acquired bloodstream infections (CABSIs) caused by P. aeruginosa. We conducted a retrospective multicenter study of consecutive P. aeruginosa bacteremia patients at two university-affiliated hospitals. Demographic, clinical, and treatment data were collected. Microbiologic analyses included in vitro susceptibility profiles and type III secretory (TTS) phenotypes. Sixty CABSI and 90 HCABSI episodes were analyzed. Patients with HCABSIs had more organ dysfunction at the time of bacteremia (P = 0.05) and were more likely to have been exposed to antimicrobial therapy (P < 0.001) than those with CABSIs. Ninety-two percent of the carbapenem-resistant P. aeruginosa infections were characterized as HCABSIs. The 30-day mortality rate for CABSIs was 26% versus 36% for HCABSIs (P = 0.38). The sequential organ failure assessment score at the time of bacteremia (hazard ratio [HR], 1.2; 95% confidence interval [CI], 1.1 to 1.3) and the TTS phenotype (HR 2.1; 95% CI, 1.1 to 3.9) were found to be independent predictors of the 30-day mortality rate. No mortality rate difference was observed between CABSIs and HCABSIs caused by P. aeruginosa. Severity of illness and expression of TTS proteins were the strongest predictors of the 30-day mortality rate due to P. aeruginosa bacteremia. Future P. aeruginosa bacteremia trials designed to neutralize TTS proteins are warranted.
authors.affiliation: The Veterans Affairs Western New York Healthcare System, Western New York, Buffalo, New York, USA.
authors.forename: Angela
authors.initials: A
authors.lastname: Hattemer
authors.forename: Alan
authors.initials: A
authors.lastname: Hauser
authors.forename: Maureen
authors.initials: M
authors.lastname: Diaz
authors.forename: Marc
authors.initials: M
authors.lastname: Scheetz
authors.forename: Nirav
authors.initials: N
authors.lastname: Shah
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Allen
authors.forename: Jahan
authors.initials: J
authors.lastname: Porhomayon
authors.forename: Ali A
authors.initials: AA
authors.lastname: El-Solh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016470:Bacteremia / Q000382:microbiology*; D058947:Bacterial Secretion Systems; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000382:microbiology* / Q000401:mortality; D016001:Confidence Intervals; D003428:Cross Infection / Q000188:drug therapy / Q000382:microbiology* / Q000401:mortality; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D017052:Hospital Mortality; D006785:Hospitals, University; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011552:Pseudomonas Infections / Q000188:drug therapy / Q000401:mortality; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification / Q000472:pathogenicity*; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D058947:Bacterial Secretion Systems