An international team of researchers has developed a simple, noninvasive urine test that might determine patients at risk of end-stage chronic kidney disease (CKD). The study, by scientists from the University of Michigan, the European Renal cDNA Bank and the Joint Institute for Translational and Clinical Research (a partnership between Peking University Health Sciences Center and Michigan), is titled “Tissue transcriptome-driven identification of epidermal growth factor as a chronic kidney disease biomarker” and published in Science Translational Medicine.
Early CKD detection can prevent disease progression to kidney failure, although it is difficult to predict which patients are at higher risk and need more aggressive treatment. The current assessment method is a kidney biopsy, an invasive and costly technique with limited success.
The researchers — led by nephrologist Matthias Kretzler, MD; renal systems biologist Wenjun Ju, PhD, MS; and bioinformatician Viji Nair, MS — discovered that measuring a urinary protein called epidermal growth factor (EGF) can indicate if a patient is at risk of progressing to end-stage kidney disease, where the kidneys fail to perform their essential role of blood filtration and waste removal. Decreased levels of EGF were found to be linked with worsening disease, and patients who presented low levels of this protein had four times the risk of developing end-stage disease, which likely requires they undergo either dialysis or kidney transplant and raises their chances of cardiovascular disease. This correlation was confirmed in urine sample analysis from more than 940 patients across North America, Europe, and China.
“Urinary epidermal growth factor can help patients in two very important ways. First, in clinical practice, it could be used to prioritize care to those patients most at risk of losing their kidney function. Second and more immediately, using urinary epidermal growth factor levels will improve and speed up clinical trials. Enrolling only those likely to develop specific disease endpoints can reduce the number of people needing study and ensure the trial achieves an optimal mix of patients,” Dr. Kretzler said in a press release.
Researchers theorize this test could reduce the cost of clinical trials by 75% and speed up the process of finding new therapies, while at the same time sparing patients the discomfort and risks of invasive biopsies.