Diagnosing Kidney Disease with the Breath
Affecting nearly 15% of the U.S. population, chronic renal disease occurs when the kidneys cannot properly eliminate water and metabolites from the body. As a result, certain chemical compounds accumulate and are elevated in the breath.
An interdisciplinary team of physicians and basic and clinical researchers at Cleveland Clinic identified five of these compounds in the breath that are associated with end-stage renal disease.
The team of researchers used a technique to identify trace amounts of gas (called selective-ion flow-tube spectrometry) to analyze the breath of 86 patients with known cases of end-stage renal disease and 25 healthy volunteers. They found that the sick patients had significantly higher levels of three known volatile organic compounds (2-propanol, ammonia and acetaldehyde) and two unnamed compounds (O2+50 and NO+76) than those without the disease.
With this knowledge, the researchers created and validated a statistical model that effectively determined from a blind sample which patients had renal failure and which did not.
These findings have very promising implications for a disease which is commonly asymptomatic and currently only diagnosed with a blood test. While additional studies are needed, this proof-of-concept research provides reason to believe that a non-invasive breath test may one day exist to quickly diagnose kidney disease.
Raed Dweik, MD, staff member in Lerner Research Institute's Department of Pathobiology, pulmonologist and director of the Pulmonary Vascular Program in the Respiratory Institute, is lead author on the study, which was published in the Journal of Breath Research.
Dr. Dweik also directs the citywide Mentored Clinical Research Scholars (KL2) program at the Clinical and Translational Science Collaborative in Cleveland. This program enables early-stage investigators to learn and conduct collaborative clinical research alongside experienced mentors. Dr. Dweik's breath analysis project, which exists at the intersection of direct patient care and clinical research, is a prime example of the type of collaborative, multi-disciplinary research project the KL2 program well prepares scholars for in the future.
The KL2 program is supported by the National Center for Advancing Translational Sciences, part of the National Institutes of Health, through Clinical and Translational Science Awards.