The study ‘shows that measurement using a urine test provides improved accuracy relative to other measurement methods, for example certain kinds of blood tests,’ a KI news release states

Researchers at the Karolinska Institute (KI) in Sweden have developed a non-invasive urine-based test that can identify what type of asthma a patient has and its severity. If developed into a clinical laboratory diagnostic, such a test also could give clinicians a better idea of what treatment is more likely to be effective—a core goal of precision medicine.

Another benefit of this methodology is that it is a non-invasive test. Should further studies conclude that this urine-based test produces accurate results acceptable for clinical settings, medical laboratories would certainly be interested in offering this assay, particularly for use in pediatric patients who are uncomfortable with the venipunctures needed to collect blood specimens. Also, given the incidence of asthma in the United States, there is the potential for a urine-based asthma test to generate a substantial number of test requests.

The objective of the study, according to the Karolinska Institute researchers, was “To test if urinary eicosanoid metabolites can direct asthma phenotyping.” The team used mass spectrometry to measured certain lipid biomarkers (prostaglandins and leukotrienes), which are known to play a key role in the inflammation that occurs during asthma attacks.

According to a KI news release, “The study is based on data from the U-BIOPRED study (Unbiased BIOmarkers in PREDiction of respiratory disease outcomes), which was designed to investigate severe asthma. The study included 400 participants with severe asthma, which often requires treatment with corticosteroid tablets, nearly 100 individuals with milder forms of asthma, and 100 healthy control participants.”

The Karolinska Institute researchers published their study in the American Journal of Respiratory and Critical Care Medicine.

Johan Kolmert, PhD

“We discovered particularly high levels of the metabolites of the mast cell mediator prostaglandin D2 and the eosinophil product leukotriene C4 in asthma patients with what is referred to as Type 2 inflammation. Using our methodology, we were able to measure these metabolites with high accuracy and link their levels to the severity and type of asthma,” said Johan Kolmert, PhD (above), a post-doctoral researcher at the Institute of Environmental Medicine, Karolina Institute, and first author of the study, in the KI news release. If perfected, such accuracy could lead to effective precision medicine clinical laboratory tests. (Photo copyright: Karolinska Institute.)

More Accurate Testing Could Lead to Biomarker-guided Precision Medicine

In the US alone, 25,131,132 people currently suffer from asthma, about five million of which are children under the age of 18, according to 2019 CDC statistics. The World Health Organization (WHO) reports that worldwide, “Asthma affected an estimated 262 million people in 2019 and caused 461,000 deaths.”

People with mild asthma may have good success using steroid inhalers. However, for those with moderate to severe asthma where inhalers are not effective, oral corticosteroids may also be necessary. But corticosteroids have been associated with high blood pressure and diabetes, among other negative side effects.

“To replace corticosteroid tablets, in recent times several biological medicines have been introduced to treat patients with Type 2 inflammation characterized by increased activation of mast cells and eosinophils,” said Sven-Erik Dahlén, Professor at the Institute of Environmental Medicine, Karolinska Institute, in the news release.

Currently, there are no simple tests that show what type of asthma a patient has. Instead, clinicians rely on lung function tests, patient interviews, allergy tests, and blood tests.

Other Non-invasive Urine-based Diagnostic Tests

In “University of East Anglia Researchers Develop Non-Invasive Prostate Cancer Urine Test,” Dark Daily recently reported on a different urine-based prostate cancer test developed in the UK that University of East Anglia (UEA) Norwich Medical School researchers say can “determine the aggressiveness of the disease” and potentially “reduce the number of unnecessary prostate cancer biopsies by 32%.”

Earlier this year, researchers at Brigham and Women’s Hospital and Exosome Diagnostics in Massachusetts investigated a non-invasive, urine-based test for transplant rejection. According to a news release, “Patients can spend up to six years waiting for a kidney transplant. Even when they do receive a transplant, up to 20% of patients will experience rejection.”

“If rejection is not treated, it can lead to scarring and complete kidney failure. Because of these problems, recipients can face life-long challenges,” said Jamil Azzi, MD, Director of the Kidney Transplantation Fellowship Program at Brigham and Women’s Hospital, and Associate Professor of Medicine at Harvard School of Medicine. “Our goal is to develop better tools to monitor patients without performing unnecessary biopsies. We try to detect rejection early, so we can treat it before scarring develops,” he said.

Detecting Bladder Cancer with Urine Testing

Another condition where urine tests are being investigated is bladder cancer. An article in Trends in Urology and Men’s Health states, “Several point-of-care urine tests have been developed to help identify patients who may be at higher risk of bladder cancer.” Those tests could have the potential for use in primary care, which could mean fewer people would need invasive, painful, and risk-carrying cystoscopies.

“New tests to help identify hematuria patients who are at a higher risk of cancer would help to improve the diagnostic pathway, reduce the number diagnosed by emergency presentation, lessen the burden on urology services, and spare those who do not have cancer an invasive and costly examination, such as cystoscopy,” the article’s authors wrote.

These urine-based tests are still under investigation by various research teams and more research is needed before clinical trials can be conducted and the tests can be submitted for regulatory approval. Though still in the early stages of development, urine-based diagnostic testing represents far less invasive, and therefore safer, ways to identify and treat various diseases.

Studies into how the elements in urine might be used as biomarkers for clinical laboratory tests may lead to improved non-invasive precision medicine diagnostics that could save many lives.

—Dava Stewart

Related Information

Urinary Leukotriene E4 and Prostaglandin D2 Metabolites Increase in Adult and Childhood Severe Asthma Characterized by Type 2 Inflammation. A Clinical Observational Study

Lipid Biomarkers in Urine Can Determine the Type of Asthma:

The U-BIOPRED Severe Asthma Study: Immunopathological Characterization

Novel Urine Test Developed to Diagnose Human Kidney Transplant Rejection

A Urine Test for Bladder Cancer: Available Soon in Primary Care?

University of East Anglia Researchers Develop Non-Invasive Prostate Cancer Urine Test

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