title: Assessment of a four hour delay for urine samples stored without preservatives at room temperature for urinalysis.
abstract: OBJECTIVE
  To determine whether urine storage at room temperature for up to 2h versus 4h changes urinalysis results.
  
  
  METHODS
  We compared the rejection rate at eight different hospital laboratories and concordance of urinalysis results (n=83; two laboratories) between urines analyzed within 2h and 4h after collection.
  
  
  RESULTS
  The rejection rate at the two hour cutoff was significantly higher as compared to the four hour cutoff. The concordance between urinalysis results was 97-100% between the two and four hour analyses.
  
  
  CONCLUSIONS
  Urine may be stored for up to 4h at room temperature without significant changes to the urinalysis results.
authors.affiliation: McMaster University, Department of Pathology and Molecular Medicine, 1200 Main Street West, Hamilton, ON, Canada L8N 3Z5. kika.veljkovic@medportal.ca
authors.forename: Kika
authors.initials: K
authors.lastname: Veljkovic
authors.forename: Karina
authors.initials: K
authors.lastname: Rodríguez-Capote
authors.forename: Vipin
authors.initials: V
authors.lastname: Bhayana
authors.forename: Robin
authors.initials: R
authors.lastname: Pickersgill
authors.forename: John
authors.initials: J
authors.lastname: Beattie
authors.forename: Lorna
authors.initials: L
authors.lastname: Clark
authors.forename: Peter A
authors.initials: PA
authors.lastname: Kavsak
mesh_terms: D002170:Canada; D002265:Carboxylic Ester Hydrolases / Q000652:urine; D005947:Glucose / Q000032:analysis; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007659:Ketones / Q000652:urine; D009573:Nitrites / Q000652:urine; D011310:Preservatives, Pharmaceutical / Q000737:chemistry; D012189:Retrospective Studies; D013046:Specific Gravity; D013048:Specimen Handling / Q000379:methods* / Q000592:standards; D013696:Temperature; D013997:Time Factors; D016482:Urinalysis / Q000379:methods* / Q000592:standards; D014556:Urine / Q000737:chemistry*
chemical_list: D006454:Hemoglobins; D007659:Ketones; D009573:Nitrites; D011310:Preservatives, Pharmaceutical; C021443:leukocyte esterase; D002265:Carboxylic Ester Hydrolases; D005947:Glucose