The Pee Glossary: Urine Science Made Easy
Urine holds a lot of information. Among other elements, it is a mixture of various cellular components, biochemicals, proteins and can be a good indicator of overall health.
Several biomarkers for different diseases have been identified in urine. As a result, urine as a sample type offers potential in clinical research for disease diagnosis, monitoring and progression. Additionally, urine also presents benefits as it allows for easy, non-invasive collection and can be obtained in large quantities (1).
The content of urine, such as the urinary proteome, however, can change at different points of the day, and can be affected by various activities including exercise, diet, medication and lifestyle (1). Furthermore, urine components, such as human DNA, are not the same in all fractions (2).
There is a range of terminology used in the field to characterize the different times and fractions of urine collection:
- First-Morning: Urine collected at the start of the day. First-morning samples are shown to be the most concentrated, and contain more proteins than urine collected in the afternoon and in the evening (1).
- First-Void/Catch/Pass: First urine flow collected at any time of the day. First-void urine is typically referred to the first 20 mL of urine flush (3). Several studies have shown that for STIs, in particular, first-void urine samples allow for improved sensitivity. It contains a significantly higher concentration of Human Papillomavirus (HPV) DNA than subsequent fractions (4). Similarly, first-void urine performs better for detection of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Mycoplasma genitalium (MG) infections in men (3). This fraction of urine contains high concentration of elements, such as CT elementary bodies, antigens as well as inflammatory enzymes (5). Additionally, for women, while testing methods are not as standardized, urine has also shown to be a good indicator, and offer similar sensitivities to cervical and vaginal specimens for detection of CT and NG (6). First-void urine is also a promising source to detect biomarkers for prostate cancer (7).
- Midstream: Urine collected after discarding the first 10 – 50 mL. This is often considered the standard fraction for detection of metabolic diseases and urinary tract infections as it is thought to contain less PCR inhibitors (8). It is also preferred in some situations as it reduces the risk of sample contamination from bacteria from other parts of the body, including the hands and skin around the urethra (9).
- Random: Urine collected at any time of the day and any fraction type. This sample collection is easy and does not require extra handling, but is not always the preferred choice.
Given the importance of timing and urine fractions on its end goal, Novosanis developed Colli-Pee®, a first-void urine capturing device. The unique design of the device allows easy collection of first-void urine, which can often be challenging and difficult for individuals. Novosanis has also recently launched Colli-Pee® variants alongside its original 20 mL, allowing collection of small volumes (up to 10 mL) and larger volumes (up to 45 mL) of urine for various applications.
(1) Shao C, Wang Y, Gao Y. Applications of urinary proteomics in biomarker discovery. Sci China Life Sci. 2011 May;54(5):409-17. doi: 10.1007/s11427-011-4162-1. Epub 2011 Mar 31. PubMed PMID: 21455690
(2) Vorsters A, Van den Bergh J, Micalessi I, Biesmans S, Bogers J, Hens A, De Coster I, Ieven M, Van Damme P. Optimization of HPV DNA detection in urine by improving collection, storage, and extraction. Eur J Clin Microbiol Infect Dis. 2014 Nov;33(11):2005-14. doi: 10.1007/s10096-014-2147-2. Epub 2014 Jun 12. PubMed PMID: 24916950.
(3) De Baetselier I, Smet H, Abdellati S, De Deken B, Cuylaerts V, Reyniers T, Vuylsteke B, Crucitti T. Evaluation of the 'Colli-Pee', a first-void urine collection device for selfsampling at home for the detection of sexually transmitted infections, versus a routine clinic-based urine collection in a one-to-one comparison study design: efficacy and acceptability among MSM in Belgium. BMJ Open. 2019 Apr 3;9(4):e028145. doi:10.1136/bmjopen-2018-028145. PubMed PMID: 30948618; PubMed Central PMCID:PMC6500257.
(4) Pattyn J, Van Keer S, Biesmans S, Ieven M, Vanderborght C, Beyers K, Vankerckhoven V, Bruyndonckx R, Van Damme P, Vorsters A. Human papillomavirus detection in urine: Effect of a first-void urine collection device and timing of collection. J Virol Methods. 2019 Feb;264:23-30. doi: 10.1016/j.jviromet.2018.11.008. Epub 2018 Nov 16. PubMed PMID: 30452931.
(5) Wisniewski CA, White JA, Michel CE, Mahilum-Tapay L, Magbanua JP, Nadala EC Jr, Barber PJ, Goh BT, Lee HH. Optimal method of collection of first-void urine for diagnosis of Chlamydia trachomatis infection in men. J Clin Microbiol. 2008 Apr;46(4):1466-9. doi: 10.1128/JCM.02241-07. Epub 2008 Jan 30. PubMed PMID: 18234860. PubMed Central PMCID: PMC2292916.
(6) Rönn MM, Mc Grath-Lone L, Davies B, Wilson JD, Ward H. Evaluation of the performance of nucleic acid amplification tests (NAATs) in detection of chlamydia and gonorrhoea infection in vaginal specimens relative to patient infection status: a systematic review. BMJ Open. 2019 Jan 17;9(1):e022510. doi: 10.1136/bmjopen-2018-022510. PubMed PMID: 30659036 PubMed Central PMCID: PMC6340625.
(7) Theodorescu D, Schiffer E, Bauer HW, Douwes F, Eichhorn F, Polley R, Schmidt T, Schöfer W, Zürbig P, Good DM, Coon JJ, Mischak H. Discovery and validation of urinary biomarkers for prostate cancer. Proteomics Clin Appl. 2008 Mar 7;2(4):556-570. PubMed PMID: 19759844; PubMed Central PMCID: PMC2744126.
(8) Vorsters A, Micalessi I, Bilcke J, Ieven M, Bogers J, Van Damme P. Detection of human papillomavirus DNA in urine. A review of the literature. Eur J Clin Microbiol Infect Dis. 2012 May;31(5):627-40. doi: 10.1007/s10096-011-1358-z. Epub 2011 Aug 5. PubMed PMID: 21818524
(9) NHS Website - https://www.nhs.uk/common-health-questions/infections/how-should-i-collect-and-store-a-urine-sample/ - Page last reviewed: 27 August 2019