Everybody pees, you knew that. On average an adult produces 6.3 cups of urine a day (1). Urine is an easily accessible body fluid, and collection is quick, and can be performed independently. As a result, urine is increasingly becoming attractive in monitoring and detecting various diseases.
On World Health Day, we want to share 7 interesting and probably lesser known facts about urine as a sample type:
#1 - Urine contains a HUGE amount of information
You probably don’t pay much attention to your pee, but urine can be a good indicator of overall health. While 95% of urine is water, it is also a rich source of other components (1), including DNA, RNA and proteins. Several conditions can cause an increase or decrease as well as abnormal components to be present in urine.
#2 - Urine collection methods are not equal
Most of us have given a urine test at some point in our lives. While urine capturing may seem simple, there are practical challenges and gender specific issues with sample collection, which can in turn affect sample quality. Traditionally, urine is collected by an individual urinating directly into a container, stopping flow when the container is full, and then continuing to urinate into the toilet. However, for men stopping urine flow midway can be difficult, whereas women can face difficulties in positioning the container in a correct manner. Our urine capturing device, Colli-Pee has a unique inherent float system, which allows superfluous urine to pass directly into the toilet without having to interrupt flow (12), requiring less effort from the user.
#3 - Reproducible urine testing requires well-standardized procedures for sample collection, transport, storage and preparation
Urine collection is only one part of the process. In order to gain accurate results, it is important to monitor steps of collection and processing. Studies have shown that the time between collection and analysis is also important. Urine stability ranges from two hours up to six hours or longer depending on the type of analysis. The addition of preservative can allow substantial longer preservation of urine and its critical content for diagnostic purposes (3). The latest design of Colli-Pee is suitable for applications that require a prefilled preservative, offering numerous transport and handling options.
#4 - Urine fractions are not equal
It may be surprising to know that urine components are not the same in all portions, and timing of specimen collection is important. For sexually transmitted infections (STIs) in particular, a first-void urine (initial 20ml) sample should be collected. First-void urine contains more DNA and RNA particles, as well as other analytes than other fractions such as a random or midstream urine sample, thereby improving diagnostic sensitivity of STIs like Human Papillomavirus (HPV) and Chlamydia (2,9,11)
Alongside STIs, some cancer types, such as prostate cancer can also be detected in urine. Studies have identified specific DNA, RNA, protein, and metabolites for prostate cancer in first-void urine (8,10). Colli-Pee allows a user-friendly method to capture a first-void urine, making sample collection easier, especially for older men who may experience difficulty in urination.
#5 - Non-invasive urine sampling has the potential to increase participation to cervical cancer screening programs
If detected at an early stage, cervical cancer is one of the most preventable cancer types. Despite the proven efficacy of screening in reducing incidence as well as mortality of cervical cancer, traditional screening procedures, including a Pap smear or a cervical HPV test, are underutilized. Reasons include the procedures are perceived time-consuming, clinician-dependent and invasive. HPV testing on urine, the primary cause of cervical cancer, offers benefits as it is quick, and non-clinician dependent (5,7). A recent study conducted in France showed the benefits of urinary HPV DNA testing in reaching women who traditionally did not attend cervical cancer screening clinics (5).
#6 - Urine testing has the potential to address the difficulties of (repeated) sampling and tumour heterogeneity
While tissue biopsies are the traditional approach used to diagnose many cancer forms, the procedure can be invasive, painful, costly and in some cases, difficult to perform, especially if the tumour site is inaccessible. Additionally, due to intratumor heterogeneity, a tissue biopsy may not always reflect the entire tumour landscape. Consequently, researchers are exploring the use of minimally invasive procedures to classify cancer types, monitor tumor development and predict treatment response. As a result, liquid biopsies and tumor detection in body fluids such as blood and urine are evolving rapidly. Studies have shown the potential of urine in detecting specific and unique tumour biomarkers for cancer types including prostate, bladder, and kidney cancer (4).
#7 - Urine testing allows to monitor the impact of HPV vaccination
Alongside screening, vaccination is vital in the fight against cervical cancer. The HPV vaccine is routinely offered to girls aged 12 to 16 in many countries across the world, and aims at protecting women against types of HPV infections. Recent vaccine impact studies conducted by the World Health Organization in Rwanda and Bhutan allowed young girls to capture urine through Colli-Pee. The results concluded that HPV presence in urine was significantly associated with sexual activity. In both Bhutan and Rwanda HPV6/11/16/18 prevalence was lower in vaccinated than in unvaccinated participants (6,7).
2. Chernesky M, Jang D, Chong S, Sellors J, Mahony J. Impact of urine collection order on the ability of assays to identify Chlamydia trachomatis infections in men. Sex Transm Dis. 2003 Apr;30(4):345-7. PubMed PMID: 12671557.
4. Di Meo A, Bartlett J, Cheng Y, Pasic MD, Yousef GM. Liquid biopsy: a step forward towards precision medicine in urologic malignancies. Mol Cancer. 2017 Apr 14;16(1):80. doi: 10.1186/s12943-017-0644-5. Review. PubMed PMID: 28410618; PubMed Central PMCID: PMC5391592.
5. Ducancelle A, Reiser J, Pivert A, Le Guillou-Guillemette H, Le Duc-Banaszuk AS, Lunel-Fabiani F. Home-based urinary HPV DNA testing in women who do not attend cervical cancer screening clinics. J Infect. 2015 Sep;71(3):377-84. doi: 10.1016/j.jinf.2015.05.001. Epub 2015 May 9. PubMed PMID: 25964233.
6. Franceschi S, Chantal Umulisa M, Tshomo U, Gheit T, Baussano I, Tenet V, Tshokey T, Gatera M, Ngabo F, Van Damme P, Snijders PJ, Tommasino M, Vorsters A, Clifford GM. Urine testing to monitor the impact of HPV vaccination in Bhutan and Rwanda. Int J Cancer. 2016 Aug 1;139(3):518-26. doi: 10.1002/ijc.30092. Epub 2016 Apr 15. PubMed PMID: 26991686.
7. Franceschi S, Clifford GM, Baussano I. Options for design of real-world impact studies of single-dose vaccine schedules. Vaccine. 2018 Aug 6;36(32 Pt A):4816-4822. doi: 10.1016/j.vaccine.2018.02.002. Epub 2018 Mar 21. PubMed PMID: 29571973; PubMed Central PMCID: PMC6066174.
9. 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.
10. 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.
11. Van Keer S, Pattyn J, Tjalma WAA, Van Ostade X, Ieven M, Van Damme P, Vorsters A. First-void urine: A potential biomarker source for triage of high-risk human papillomavirus infected women. Eur J Obstet Gynecol Reprod Biol. 2017 Sep;216:1-11. doi: 10.1016/j.ejogrb.2017.06.036. Epub 2017 Jun 27. Review. PubMed PMID: 28689156.
12. Vorsters A, Van Keer S, Van Damme P. The use of urine in the follow-up of HPV vaccine trials. Hum Vaccin Immunother. 2015;11(2):350-2. doi: 10.4161/21645515.2014.995058. PubMed PMID: 25664398; PubMed Central PMCID: PMC4514373.