Urine test
| Urine test | |
|---|---|
 A urine sample in a sterile container |
A urine test is any
Background
The value of urine for diagnostic purposes has been recognized since ancient times. Urine examination was practiced in
Specimen collection
The techniques used to collect urine specimens vary based on the desired test. A random urine, meaning a specimen that is collected at any time, can be used for many tests. However, a sample collected during the first urination of the morning (first morning specimen) is preferred for tests like urinalysis and pregnancy screening because it is typically more concentrated, making the test more
If urine is needed for microbiological culture, it is important that the sample is not contaminated. In this case, the proper collection procedure involves cleaning the genital area, beginning to urinate into the toilet, and then filling the specimen container before completing the urination into the toilet. This is called a "midstream clean catch" collection.[1] Research has shown many women are unsure of how to take a midstream sample or why it is needed.[11] [12]
If the subject is not able to urinate voluntarily, samples can be obtained using a
Types
Some examples of urine tests include:
Chemistry
- urine test strips, and microscopic examination[13]
- creatinine clearance — used to assess kidney function[14]
- Albumin/creatinine ratio — used to diagnose microalbuminuria[15]
- solute concentration of urine[16]
- Urine specific gravity ― another measure of urine concentration[16]
- Urine anion gap — used to distinguish between some causes of metabolic acidosis[18]
Hormones
- Urine pregnancy test ― detects human chorionic gonadotropin in urine[5]
- Urine cortisol ― used to investigate disorders of the adrenal glands[19]
- tumours[20]
Microbiology
- Urine culture — microbiological culture of urine samples, used to identify bacteria causing urinary tract infections[4]
Miscellaneous
- recreational drugs[6]
- cytopathological examination of cells in the urine, used to screen for cancer[21]
- monoclonal gammopathies[22]
- urine amino acids — used to test for some inborn errors of metabolism[8]
References
- ^ a b c d e Brunzel 2018, pp. 19–22.
- PMID 17191081.
- ^ from the original on 5 April 2022. Retrieved 13 July 2022.
- ^ a b Turgeon 2016, p. 505.
- ^ a b Turgeon 2016, p. 216.
- ^ S2CID 21260113.
- ^ McPherson & Pincus 2017, p. 479.
- ^ a b Rifai, Horvath & Wittwer 2018, p. 1697.
- ^ Mundt & Shanahan 2016, p. 264.
- ^ Mundt & Shanahan 2016, pp. 75–6.
- ^ "Do women know how to take a urine sample?". NIHR Evidence. 11 December 2022.
- PMID 35190371.
- ^ McPherson & Pincus 2017, pp. 441–3.
- ^ McPherson & Pincus 2017, pp. 167–8.
- ^ Turgeon 2016, p. 255.
- ^ a b Brunzel 2018, pp. 51–3.
- PMID 20193886.
- ^ Reddi 2014, pp. 13−4.
- ^ McPherson & Pincus 2017, p. 391.
- ^ Rifai, Horvath & Wittwer 2018, p. 1421.
- S2CID 52171396.
- ^ McPherson & Pincus 2017, p. 253.
Works cited
- Brunzel NA (2018). Fundamentals of Urine and Body Fluid Analysis (4th ed.). ISBN 978-0-323-37479-8.
- McPherson RA, Pincus MR (2017). Henry's Clinical Diagnosis and Management by Laboratory Methods (23 ed.). Elsevier Health Sciences. ISBN 978-0-323-41315-2.
- Mundt LA, Shanahan K (2016). Graff's Textbook of Urinalysis and Body Fluids (3 ed.). ISBN 978-1-4963-2016-2.
- Reddi AS (2014). Fluid, electrolyte, and acid-base disorders: clinical evaluation and management. ISBN 978-1-4614-9082-1.
- Rifai N, Horvath AR, Wittwer CT (2018). Tietz Textbook of Clinical Chemistry and Molecular Diagnostics (6th ed.). Elsevier. ISBN 978-0-323-35921-4.
- Turgeon ML (2016). Linné & Ringsrud's Clinical Laboratory Science: Concepts, Procedures, and Clinical Applications (7 ed.). Elsevier Mosby. ISBN 978-0-323-22545-8.