Taking the unknown out of CKDu: Read the new report from ISN i3C in Kidney International®
After two decades of research, the causes of chronic kidney disease of undetermined etiology (CKDu) remain elusive. A new report from the ISN International Consortium of CKDu Collaborators (ISN i3C), published in Kidney International® (KI), suggests the challenge lies not only in what is unknown but also in how CKDu has been studied to date.
The authors point to inconsistent terminology, blurred distinctions between disease onset and progression, and heavy reliance on self-reported exposures as key barriers to progress in research on CKDu. Many proposed causes of CKDu, including heat stress, are also known to exacerbate kidney disease more broadly, making it difficult to determine whether they initiate disease or worsen it.
While the underlying causes remain under investigation, the report calls for more disciplined research approaches and emphasizes continued action to reduce known risks, such as occupational heat exposure.
Led by Eranga Wijewickrama and Ben Caplin, chair and deputy chair of the ISN i3C Working Group, the report draws on ISN i3C discussions at the World Congress of Nephrology 2025.
Researchers interested in contributing can join the ISN i3C Network at ckdu_observatory@theisn.org.
