Performance characteristics of urine dipsticks stored in open containers

E. John Gallagher, Edward Schwartz, Roslyn S. Weinstein

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

Dip and read urinalysis is a laboratory test commonly performed by emergency physicians. Although the manufacturer states that the capped vials containing the dipsticks must be closed immediately after removal of a strip, this recommendation may not be followed in a busy emergency department. In a simple, two-part, blinded, and controlled trial the authors found that the reagents for determining leukocyte esterase, pH, protein, glucose, ketones, urobilinogen, bilirubin, and blood showed good reproducibility when fresh dipsticks were compared with dipsticks exposed to room temperature and humidity for 1 to 15 days. In contrast to this, the nitrite portion of the exposed dipsticks showed a rapid and cumulative loss of specificity over time. By the end of a week of exposure, one third of the nitrite tests gave false-positive readings. At the end of a second week, nearly three quarters gave false-positive readings for a specificity of only 28%. It is concluded that the nitrite reagent, in contrast to the other eight reagents on the Chemstrip-9 dipstick (Biodynamics, indianapolis, IN), rapidly loses accuracy when stored in uncapped vials.

Original languageEnglish (US)
Pages (from-to)121-123
Number of pages3
JournalAmerican Journal of Emergency Medicine
Volume8
Issue number2
DOIs
StatePublished - 1990

Fingerprint

Nitrites
Urine
Reading
Urobilinogen
Urinalysis
Humidity
Ketones
Bilirubin
Hospital Emergency Service
Emergencies
Physicians
Glucose
Temperature
Proteins

Keywords

  • errors in dipstick urinalysis
  • falsepositive nitrate reagent test
  • Urinalysis

ASJC Scopus subject areas

  • Emergency Medicine

Cite this

Performance characteristics of urine dipsticks stored in open containers. / Gallagher, E. John; Schwartz, Edward; Weinstein, Roslyn S.

In: American Journal of Emergency Medicine, Vol. 8, No. 2, 1990, p. 121-123.

Research output: Contribution to journalArticle

Gallagher, E. John ; Schwartz, Edward ; Weinstein, Roslyn S. / Performance characteristics of urine dipsticks stored in open containers. In: American Journal of Emergency Medicine. 1990 ; Vol. 8, No. 2. pp. 121-123.
@article{dc109f3abb124e3f9fe495f67ec19a07,
title = "Performance characteristics of urine dipsticks stored in open containers",
abstract = "Dip and read urinalysis is a laboratory test commonly performed by emergency physicians. Although the manufacturer states that the capped vials containing the dipsticks must be closed immediately after removal of a strip, this recommendation may not be followed in a busy emergency department. In a simple, two-part, blinded, and controlled trial the authors found that the reagents for determining leukocyte esterase, pH, protein, glucose, ketones, urobilinogen, bilirubin, and blood showed good reproducibility when fresh dipsticks were compared with dipsticks exposed to room temperature and humidity for 1 to 15 days. In contrast to this, the nitrite portion of the exposed dipsticks showed a rapid and cumulative loss of specificity over time. By the end of a week of exposure, one third of the nitrite tests gave false-positive readings. At the end of a second week, nearly three quarters gave false-positive readings for a specificity of only 28{\%}. It is concluded that the nitrite reagent, in contrast to the other eight reagents on the Chemstrip-9 dipstick (Biodynamics, indianapolis, IN), rapidly loses accuracy when stored in uncapped vials.",
keywords = "errors in dipstick urinalysis, falsepositive nitrate reagent test, Urinalysis",
author = "Gallagher, {E. John} and Edward Schwartz and Weinstein, {Roslyn S.}",
year = "1990",
doi = "10.1016/0735-6757(90)90197-8",
language = "English (US)",
volume = "8",
pages = "121--123",
journal = "American Journal of Emergency Medicine",
issn = "0735-6757",
publisher = "W.B. Saunders Ltd",
number = "2",

}

TY - JOUR

T1 - Performance characteristics of urine dipsticks stored in open containers

AU - Gallagher, E. John

AU - Schwartz, Edward

AU - Weinstein, Roslyn S.

PY - 1990

Y1 - 1990

N2 - Dip and read urinalysis is a laboratory test commonly performed by emergency physicians. Although the manufacturer states that the capped vials containing the dipsticks must be closed immediately after removal of a strip, this recommendation may not be followed in a busy emergency department. In a simple, two-part, blinded, and controlled trial the authors found that the reagents for determining leukocyte esterase, pH, protein, glucose, ketones, urobilinogen, bilirubin, and blood showed good reproducibility when fresh dipsticks were compared with dipsticks exposed to room temperature and humidity for 1 to 15 days. In contrast to this, the nitrite portion of the exposed dipsticks showed a rapid and cumulative loss of specificity over time. By the end of a week of exposure, one third of the nitrite tests gave false-positive readings. At the end of a second week, nearly three quarters gave false-positive readings for a specificity of only 28%. It is concluded that the nitrite reagent, in contrast to the other eight reagents on the Chemstrip-9 dipstick (Biodynamics, indianapolis, IN), rapidly loses accuracy when stored in uncapped vials.

AB - Dip and read urinalysis is a laboratory test commonly performed by emergency physicians. Although the manufacturer states that the capped vials containing the dipsticks must be closed immediately after removal of a strip, this recommendation may not be followed in a busy emergency department. In a simple, two-part, blinded, and controlled trial the authors found that the reagents for determining leukocyte esterase, pH, protein, glucose, ketones, urobilinogen, bilirubin, and blood showed good reproducibility when fresh dipsticks were compared with dipsticks exposed to room temperature and humidity for 1 to 15 days. In contrast to this, the nitrite portion of the exposed dipsticks showed a rapid and cumulative loss of specificity over time. By the end of a week of exposure, one third of the nitrite tests gave false-positive readings. At the end of a second week, nearly three quarters gave false-positive readings for a specificity of only 28%. It is concluded that the nitrite reagent, in contrast to the other eight reagents on the Chemstrip-9 dipstick (Biodynamics, indianapolis, IN), rapidly loses accuracy when stored in uncapped vials.

KW - errors in dipstick urinalysis

KW - falsepositive nitrate reagent test

KW - Urinalysis

UR - http://www.scopus.com/inward/record.url?scp=0025232459&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0025232459&partnerID=8YFLogxK

U2 - 10.1016/0735-6757(90)90197-8

DO - 10.1016/0735-6757(90)90197-8

M3 - Article

C2 - 2302279

AN - SCOPUS:0025232459

VL - 8

SP - 121

EP - 123

JO - American Journal of Emergency Medicine

JF - American Journal of Emergency Medicine

SN - 0735-6757

IS - 2

ER -