title: Evaluation and optimization of the Sysmex UF1000i system for the screening of urinary tract infection in primary health care elderly patients.
abstract: OBJECTIVE
  Urinary tract infections (UTIs) are a common problem in the elderly population. Urine culture is still considered the "gold standard" to diagnose infection in this population. However, urine cultures are laborious and costly, and most samples will yield no growth.
  
  
  METHODS
  An evaluation was made of the Sysmex UF-1000i flow cytometer as a screening tool for UTI in an elderly population older than 65 years who lived in the community, using 346 urine samples submitted for culture.
  
  
  RESULTS
  The Receiver Operating Characteristic (ROC) analysis showed a significant difference (P<0.01) between 0.98 bacteria area under the curve value and 0.82 of white blood cells (WBC). The combination of both counts for screening did not show any improvement in specificity or sensitivity. According to our data, the use of a single cut-off point of 200bacteria/μL is suggested, in which the sensitivity and specificity were 99.11% and 91.59%, respectively, with a NPV of 99.49%. Moreover, this cut-off value could avoid 60.24% of the samples to be cultured, with a minimal false negative results rate of 0.87%.
  
  
  CONCLUSIONS
  The stratification of age groups stratification helps in selecting a more adjusted Sysmex UF1000i cut-off limit, leading to an improvement in the screening parameters that would imply a better management of these infections, as well as a high reduction in the workload and cost savings.
authors.affiliation: Infectious Diseases, Clinical Microbiology and Preventive Medicine Unit, Hospital Universitario Virgen del Rocío, Seville, Spain. Electronic address: guiller_mg86@hotmail.es.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Martín-Gutiérrez
authors.affiliation: Infectious Diseases, Clinical Microbiology and Preventive Medicine Unit, Hospital Universitario Virgen del Rocío, Seville, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Porras-González
authors.affiliation: UGC Marquesado, AGS Nordeste de Granada; SAMSERAP group, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Martín-Pérez
authors.affiliation: Infectious Diseases, Clinical Microbiology and Preventive Medicine Unit, Hospital Universitario Virgen del Rocío, Seville, Spain; Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/CSIC/University of Seville, Seville, Spain.
authors.forename: Jose Antonio
authors.initials: JA
authors.lastname: Lepe
authors.affiliation: Infectious Diseases, Clinical Microbiology and Preventive Medicine Unit, Hospital Universitario Virgen del Rocío, Seville, Spain; Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/CSIC/University of Seville, Seville, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Aznar
mesh_terms: D000368:Aged; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D011320:Primary Health Care; D012372:ROC Curve; D016482:Urinalysis / Q000379:methods / Q000592:standards; D014552:Urinary Tract Infections / Q000175:diagnosis* / Q000652:urine*; D014556:Urine / Q000166:cytology / Q000382:microbiology
keywords: Citómetro de flujo; Elderly; Flow cytometry; Mayores; UTI