title: Usefulness of procalcitonin and C-reactive protein for predicting bacteremia in urinary tract infections in the emergency department.
abstract: BACKGROUND
  The aim of this study was to analyze and compare the capacity of procalcitonin (PCT), C-reactive protein (CRP), lactate and leukocytes to predict the presence of bacteremia in patients with urinary tract infections (UTIs).
  
  
  METHODS
  Observational, retro-prospective analytical study of adult patients (≥15 years) diagnosed with UTI in an emergency department from August 2012 to January 2013.
  
  
  RESULTS
  The study included 328 patients diagnosed with UTI, with a mean age of 52±22 years, 74% of whom were women. Of these, 43 (13.1%) had bacteremia. For predicting bacteremia, PCT achieved the largest area under the receiver operating characteristic curve (ROC-AUC) at .993 (95% CI .987-1; P<.001). A cutoff≥1.16ng/mL achieves a sensitivity of 100%, a specificity of 97%, a positive predictive value of 84% and a negative predictive value of 100%. Lactate achieved an ROC-AUC of .844, and CRP achieved only .534. The mean values when comparing PCT levels in patients with UTIs with and without bacteremia were 8.08±16.37 and .34±.37ng/mL, respectively (P<.001).
  
  
  CONCLUSIONS
  For patients with UTIs in the emergency department, PCT achieves considerable diagnostic performance for suspecting bacteremia, a performance greater than that of lactate, CRP and leukocytes.
authors.affiliation: Servicio de Urgencias, Complejo Hospitalario de Toledo, Toledo, España. Electronic address: agustinj@sescam.jccm.es.
authors.forename: A
authors.initials: A
authors.lastname: Julián-Jiménez
authors.affiliation: Servicio de Urología, Complejo Hospitalario de Toledo, Toledo, España.
authors.forename: P
authors.initials: P
authors.lastname: Gutiérrez-Martín
authors.affiliation: Servicio de Urgencias, Complejo Hospitalario de Toledo, Toledo, España.
authors.forename: A
authors.initials: A
authors.lastname: Lizcano-Lizcano
authors.affiliation: Servicio de Medicina Interna, Complejo Hospitalario de Toledo, Toledo, España.
authors.forename: M A
authors.initials: MA
authors.lastname: López-Guerrero
authors.affiliation: Servicio de Urología, Complejo Hospitalario de Toledo, Toledo, España.
authors.forename: Á
authors.initials: Á
authors.lastname: Barroso-Manso
authors.affiliation: Servicio de Microbiología, Complejo Hospitalario de Toledo, Toledo, España.
authors.forename: E
authors.initials: E
authors.lastname: Heredero-Gálvez
mesh_terms: D000328:Adult; D016470:Bacteremia / Q000097:blood* / Q000175:diagnosis / Q000209:etiology*; D002097:C-Reactive Protein / Q000032:analysis*; D002116:Calcitonin / Q000097:blood*; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012189:Retrospective Studies; D014552:Urinary Tract Infections / Q000150:complications*
chemical_list: D002116:Calcitonin; D002097:C-Reactive Protein
keywords: Bacteremia; Bacteriemia; Biomarcadores; Biomarkers; C-reactive protein; Emergency department; Infección del tracto urinario; Procalcitonin; Procalcitonina; Proteína C reactiva; Servicio de urgencias; Urinary tract infection