title: Reliability of dipstick assay in predicting urinary tract infection.
abstract: OBJECTIVE
  Urine dipstick analysis is a quick, cheap and a useful test in predicting Urinary Tract Infection (UTI) in hospitalized patients. Our aim is to evaluate the reliability (sensitivity) of urine dipstick analysis against urine culture in the diagnosis of UTI.
  
  
  METHODS
  Patients admitted to our hospital suspected of having UTI, with positive urine cultures were included in this study from a 2-year period (January 2011 to December 2012). Dipstick urinalysis was done using multistix 10 SG (Siemens) and clinitek advantus analyzer. The sensitivity of dipstick nitrites, leukocyte esterase and blood in these culture-positive UTI patients was calculated retrospectively.
  
  
  RESULTS
  Urine dipstick analysis of 635 urine culture-positive patients was studied. The sensitivity of nitrite alone and leukocyte esterase alone were 23.31% and 48.5%, respectively. The sensitivity of blood alone in positive urine culture was 63.94%, which was the highest sensitivity for a single screening test. The presence of leukocyte esterase and/or blood increased the sensitivity to 72.28%. The sensitivity was found to be the highest when nitrite, leukocyte and blood were considered together.
  
  
  CONCLUSIONS
  Nitrite test and leukocyte esterase test when used individually is not reliable to rule out UTI. Hence, symptomatic UTI patients with negative dipstick assay should be subjected to urine culture for a proper management.
authors.affiliation: Department of Medicine, PSG Institute of Medical Sciences and Research, Coimbatore, Tamil Nadu, India.
authors.forename: Anith Kumar
authors.initials: AK
authors.lastname: Mambatta
authors.affiliation: Department of Microbiology, PSG Institute of Medical Sciences and Research, Coimbatore, Tamil Nadu, India.
authors.forename: Jayalakshmi
authors.initials: J
authors.lastname: Jayarajan
authors.affiliation: Department of Medicine, PSG Institute of Medical Sciences and Research, Coimbatore, Tamil Nadu, India.
authors.forename: Vinitha L
authors.initials: VL
authors.lastname: Rashme
authors.affiliation: Department of Medicine, PSG Institute of Medical Sciences and Research, Coimbatore, Tamil Nadu, India.
authors.forename: Sanchitha
authors.initials: S
authors.lastname: Harini
authors.affiliation: Department of Medicine, PSG Institute of Medical Sciences and Research, Coimbatore, Tamil Nadu, India.
authors.forename: Sujaya
authors.initials: S
authors.lastname: Menon
authors.affiliation: Department of Medicine, PSG Institute of Medical Sciences and Research, Coimbatore, Tamil Nadu, India.
authors.forename: Jayachandran
authors.initials: J
authors.lastname: Kuppusamy
keywords: Urinary tract infection; urine culture; urine dipstick assay