News

New urine testing method holds promise for kidney stone sufferers

An improved urine-testing system for people suffering from kidney stones inspired by nature and proposed by researchers from Penn State and Stanford University may enable patients to receive results within 30 minutes instead of the current turnaround time of a week or more.

advertisement

Kidney stones occur due to buildup of certain salts and minerals that form crystals, which in turn stick together and enlarge to form a hard mass in the kidneys. The stones move into the urinary tract and can cause blood in the urine, considerable pain and blockages in the urinary system.

Metabolic testing of a kidney stone patient s urine to identify metabolites such as minerals and solutes that cause stones to form is key for preventing future ones. This testing is currently done by requiring the patient to collect their urine over a 24-hour period in a large container. The container is then sent to a lab for analysis and the results normally come back in 7 to 10 days.

"The lengthy process, cumbersome collection procedure and delay in obtaining the results render 24-hour urine testing to be underutilized in clinical practice despite guideline recommendations," said Pak Kin Wong, professor of biomedical engineering and mechanical engineering and principal investigator on the study. The research was published today (May 22) in Science Advances.

Wong said that expensive special equipment is required to detect urinary solutes and minerals for a test result. The urine sample, therefore, has to be shipped to a commercial diagnostic lab for testing. To solve this, the research team developed a biomimetic detection system called slippery liquid-infused porous surface (SLIPS)-LAB.

SLIPS is a dynamic, extremely low-friction smooth surface created by locking lubricating liquids in micro/nanostructured substrates. This is inspired by nepenthes pitcher plants, which are carnivorous plants that have unique leaves shaped like pitchers and are filled with digestive liquid. The plants have evolved extremely slippery liquid-infused micro-textured rims that cause insects to fall into the "pitcher."

"There are many aspects we can learn from nature and our environment, and our research is an example how biomedical engineers can make good use of it," Wong said.

advertisement

SLIPS-LAB works by enabling reagent and urine droplets to easily move over the slick surface of the testing device s fluid addition channel and not get stuck. The droplet is driven by a Laplace pressure difference, a small pressure force due to surface tension, induced by the geometry of the device. This enables the reactants to combine with the urine at the necessary timed rate for reaction.

"We demonstrated that SLIPS-LAB enables the reagent and sample to move themselves and perform the reactions for us," Wong said. "It means the technology doesn t require a technician to run any test machinery, so it is possible to do the test in non-traditional settings, like a physician s office or even the patient s home."

The test results can then be read using a scanner or a cell phone, and the scanned image can then be analyzed using a computer algorithm. All these steps, according to Wong, would take approximately 30 minutes in a physician s office. An added benefit, Wong said, is that SLIPS-LAB is more cost-effective than regular, 24-hour testing.

"The low cost, rapidity and simplicity of SLIPS-LAB would reduce the barrier for the clinician and patient to undergo stone risk metabolite analysis," Wong said. "This would improve the management of patients with urinary stone disease and open new possibilities for stone patients to test their urine samples in mobile health settings."

The lead author of the study, Hui Li, graduate student in biomedical engineering, said another promising result of their research was demonstrating that the test also works as a spot test, which means a patient can monitor certain levels in their urine without 24-hour collection.

"SLIPS-LAB may open new opportunities in on-demand monitoring of urinary analytes and may potentially transform metabolic evaluation and clinical management of urinary stone disease," Li said.

Materials provided by Penn State . Note: Content may be edited for style and length.

Penn State. "New urine testing method holds promise for kidney stone sufferers: Simpler test that can be done in doctor s office offers results in 30 minutes." ScienceDaily. ScienceDaily, 22 May 2020. .

Penn State. "New urine testing method holds promise for kidney stone sufferers: Simpler test that can be done in doctor s office offers results in 30 minutes." ScienceDaily. www.sciencedaily.com/releases/2020/05/200522145149.htm (accessed May 22, 2020).

advertisement

1

Sep. 13, 2018 — A geologist, a microscopist and a doctor walk into a lab and, with their colleagues, make a discovery that overturns centuries of thought about the nature and composition of kidney stones. The ...

Feb. 13, 2018 — Kidney stones are a painful health condition, often requiring multiple procedures at great discomfort to the patient. Growing evidence suggests that the incidence of kidney stones is increasing ...

June 28, 2016 — A new study into the causes of kidney stones has revealed that high levels of zinc in the body may contribute to kidney stone formation. Kidney stones are hard, often jagged masses of crystalized ...

July 21, 2015 — Tamsulosin works no better than placebo on small kidney stones, but does improve passage of more large kidney stones than placebo does, a new study concludes. 83.3 percent of patients treated with ...
Read more on sciencedaily.com
News Topics :
RELATED STORIES :
Science
Kidney stones are a common and painful condition, with many sufferers experiencing recurrent episodes. Most people who pass an initial stone want to know their chances of future episodes, but...
Science
David Killilea, PhD, a staff scientist at Children s Hospital Oakland Research Institute CHORI the research arm of UCSF Benioff Children s Hospital Oakland co authored a study into...
Science
A study conducted at the Florida theme park found that riding roller coasters may help people pass kidney stones with far less pain and no need for surgery. Researchers at...
Science
Researchers who analyzed recent trends related to urinary tract stones in the UK found a sustained and high prevalence of the condition, with an increased trend to treat patients with...
Technology
A new medical device can diagnose urinary tract infections UTIs at home in less than an hour. And, in an unusual twist, the device looks and performs almost exactly like...