title: A clinical decision rule identifies risk factors associated with antimicrobial-resistant urinary pathogens in the emergency department: a retrospective validation study.
abstract: BACKGROUND
  Identifying patients at high risk for multidrug-resistant urinary tract infections (UTIs) is important for guiding empirical antimicrobial therapy. Clinical risk factors associated with antimicrobial-resistant urinary pathogens and the derivation of a simple clinical decision rule could help define health care-associated UTI.
  
  
  OBJECTIVE
  To derive a simple clinical decision rule to identify clinical risk factors associated with antimicrobial-resistant urinary pathogens.
  
  
  METHODS
  This was a retrospective case-control study of all emergency department (ED) patients from July 1, 2011, to July 1, 2012, who presented to the ED with UTI and a positive urine culture. Candidate risk factors were collected retrospectively from medical record review. We compared differences in patient characteristics stratified by the presence of an antimicrobial-resistant urinary pathogen.
  
  
  RESULTS
  A total of 360 patients with UTI had a positive, noncontaminated urine culture during the study period. About 6.7% of patients (n = 24) had a multidrug-resistant (MDR) urinary infection. Logistic regression modeling identified 3 clinical factors associated with the identification of a MDR pathogen: male sex, chronic hemodialysis, and nursing home residence. A scoring system was created to identify patients with MDR pathogens. Test characteristics were calculated using bootstrapping for internal validation, with a sensitivity of 74.7% (95% CI = 55.1%-91.3%) and specificity of 85.1% (95% CI = 77.8%-86.2%), positive likelihood ratio of 4.3, and a negative likelihood ratio of 0.3.
  
  
  CONCLUSIONS
  Clinical factors can be used to identify UTI patients at high risk of MDR urinary pathogens.
authors: University of Iowa Hospitals and Clinics, Iowa City, IA, USA brett-faine@uiowa.edu.
authors: Brett A
authors: BA
authors: Faine
authors: University of Iowa Hospitals and Clinics, Iowa City, IA, USA.
authors: Kari K
authors: KK
authors: Harland
authors: University of Iowa College of Pharmacy, Iowa City, IA, USA.
authors: Blake
authors: B
authors: Porter
authors: Washington University in St Louis School of Medicine, MO, USA.
authors: Stephen Y
authors: SY
authors: Liang
authors: University of Iowa Hospitals and Clinics, Iowa City, IA, USA.
authors: Nicholas
authors: N
authors: Mohr
mesh_terms: D000368:Aged; D000890:Anti-Infective Agents / Q000627:therapeutic use*; D016022:Case-Control Studies; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014552:Urinary Tract Infections / Q000188:drug therapy*
chemical_list: D000890:Anti-Infective Agents
keywords: antibiotic resistance; antibiotics; emergency medicine; infectious disease; urinary tract infections