title: Risk factors for drug-resistant pathogens in immunocompetent patients with pneumonia: Evaluation of PES pathogens.
abstract: BACKGROUND
  The new acronym, PES pathogens (Pseudomonas aeruginosa, Enterobacteriaceae extended-spectrum beta-lactamase-positive, and methicillin-resistant Staphylococcus aureus), was recently proposed to identify drug-resistant pathogens associated with community-acquired pneumonia.
  
  
  OBJECTIVE
  To evaluate the risk factors for antimicrobial-resistant pathogens in immunocompetent patients with pneumonia and to validate the role of PES pathogens.
  
  
  METHODS
  A retrospective analysis of a prospective observational study of immunocompetent patients with pneumonia between March 2009 and June 2015 was conducted. We clarified the risk factors for PES pathogens.
  
  
  RESULTS
  Of the total 1559 patients, an etiological diagnosis was made in 705 (45.2%) patients. PES pathogens were identified in 51 (7.2%) patients, with 53 PES pathogens (P. aeruginosa, 34; ESBL-positive Enterobacteriaceae, 6; and MRSA, 13). Patients with PES pathogens had tendencies toward initial treatment failure, readmission within 30 days, and a prolonged hospital stay. Using multivariate analysis, female sex (adjusted odds ratio [AOR] 1.998, 95% confidence interval [CI] 1.047-3.810), admission within 90 days (AOR 2.827, 95% CI 1.250-6.397), poor performance status (AOR 2.380, 95% CI 1.047-5.413), and enteral feeding (AOR 5.808, 95% CI 1.813-18.613) were independent risk factors for infection with PES pathogens. The area under the receiver operating characteristics curve for the risk factors was 0.66 (95% CI 0.577-0.744).
  
  
  CONCLUSIONS
  We believe the definition of PES pathogens is an appropriate description of drug-resistant pathogens associated with pneumonia in immunocompetent patients. The frequency of PES pathogens is quite low. However, recognition is critical because they can cause refractory pneumonia and different antimicrobial treatment is required.
authors.affiliation: Dept. of Respiratory Medicine, Kurashiki Central Hospital, Ohara Memorial Kurashiki Central Healthcare Foundation, Kurashiki, Japan. Electronic address: ishidat@kchnet.or.jp.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Ishida
authors.affiliation: Dept. of Respiratory Medicine, Kurashiki Central Hospital, Ohara Memorial Kurashiki Central Healthcare Foundation, Kurashiki, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Ito
authors.affiliation: Dept. of Respiratory Medicine, Kurashiki Central Hospital, Ohara Memorial Kurashiki Central Healthcare Foundation, Kurashiki, Japan.
authors.forename: Yasuyoshi
authors.initials: Y
authors.lastname: Washio
authors.affiliation: Dept. of Respiratory Medicine, Kurashiki Central Hospital, Ohara Memorial Kurashiki Central Healthcare Foundation, Kurashiki, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Yamazaki
authors.affiliation: Dept. of Respiratory Medicine, Kurashiki Central Hospital, Ohara Memorial Kurashiki Central Healthcare Foundation, Kurashiki, Japan.
authors.forename: Maki
authors.initials: M
authors.lastname: Noyama
authors.affiliation: Dept. of Respiratory Medicine, Kurashiki Central Hospital, Ohara Memorial Kurashiki Central Healthcare Foundation, Kurashiki, Japan.
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Tokioka
authors.affiliation: Dept. of Respiratory Medicine, Kurashiki Central Hospital, Ohara Memorial Kurashiki Central Healthcare Foundation, Kurashiki, Japan.
authors.forename: Machiko
authors.initials: M
authors.lastname: Arita
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D017714:Community-Acquired Infections / Q000209:etiology* / Q000382:microbiology*; D003428:Cross Infection / Q000188:drug therapy / Q000209:etiology / Q000382:microbiology; D024881:Drug Resistance, Bacterial / Q000187:drug effects; D004755:Enterobacteriaceae / Q000187:drug effects / Q000302:isolation & purification*; D005260:Female; D006760:Hospitalization; D006801:Humans; D016867:Immunocompromised Host / Q000187:drug effects; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects / Q000302:isolation & purification*; D011014:Pneumonia / Q000188:drug therapy / Q000209:etiology* / Q000382:microbiology*; D011446:Prospective Studies; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000302:isolation & purification*; D012189:Retrospective Studies; D012307:Risk Factors; D001618:beta-Lactamases / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases
keywords: Drug-resistant pathogen; Immunocompetent patients; Pneumonia