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The silent epidemic of CKDu: advances, challenges, and strategies for sustainable eradication-a narrative review.
| Clinical and Experimental Nephrology | Diwyanjalee GR and Wimalawansa SJ. |
CKDu Sri Lanka Kidney Nephrotoxicity Review

Abstract

Background

Chronic kidney disease of unknown origin (CKDu) primarily affects tropical agricultural countries. Renal deposition of calcium nanocrystals and nanotubes causes it. Thus, it was renamed crystal tubular nephropathy (CKD–CTN). CKD–CTN remains a major public health crisis in Sri Lanka’s dry-zone farming regions and other equatorial countries, especially Central America, with severe social and economic consequences.

Methods

We searched public databases since 2000 using keywords to identify relevant articles. The data were systematically compiled and synthesized into a narrative review, integrating recent findings to elucidate the most likely factors contributing to the onset of CKD–CTN.

Results

Recent studies ruled out previously claimed agrochemicals, heavy metals, arsenic, and other nephrotoxins, as well as heat stress as causes. In contrast, evidence points to prolonged consumption of naturally contaminated groundwater as the primary cause. For the disease to manifest, however requires behavioral factors, such as chronic sustained dehydration, routine alcohol use, poverty-related malnutrition, etc. Together, these create sustained dehydration—ideal conditions for calcium crystal precipitation in renal tissues-a slow process, which gradually grow in the presence of fluoride into stable crystals, damaging kidneys and leading to CKD–CTN.

Conclusions

The review examines the current understanding of CKD–CTN, highlighting key environmental, biological, social, and occupational constrains and factors. It calls for a national strategy—public education, health interventions, environmental monitoring, nutritional support, policy reforms, and—most critically—universal access to affordable potable water. It stresses the urgency of sustainable water management, education, and stronger rural healthcare systems to mitigate this deadly disease AND its impact. The authors offer practical guidance for future research, interventions, and policies to prevent the burden of CKD–CTN on communities.

Data availability

All data are provided in the article and supplemental material are referenced.

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Acknowledgements

The authors express their sincere gratitude to Mr. KWKA Priyadarshana from the Department of Geography and Environmental Management, Faculty of Social Sciences, Sabaragamuwa University of Sri Lanka, for his support in improving the maps used in this study.

Funding

Authors received no funding, AI, or other writing assistance for this project.

Author information

Authors and Affiliations

  1. Southern Provincial Office, Central Environmental Authority, Galle, Sri Lanka

    G. R. Diwyanjalee

  2. CardioMetablic and Endocrine Institute, B14, G2, De Soyza Flats, Moratuwa, Sri Lanka

    S. J. Wimalawansa

Contributions

The author equally participated in conceptualization, methodology, data curation, analysis, writing, and editing.

Corresponding author

Correspondence to S. J. Wimalawansa.

ABSTRACT ONLINE AT https://link.springer.com/article/10.1007/s10157-025-02751-3