Abstract: FR-PO0700
Associations Between Toxic Metal Exposure and Childhood Nephrotic Syndrome
Session Information
- Pediatric Nephrology: CKD, ESKD, and Glomerular Diseases
November 07, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Pediatric Nephrology
- 1900 Pediatric Nephrology
Authors
- Robinson, Cal, The Hospital for Sick Children, Toronto, Ontario, Canada
- Aman, Nowrin F., The Hospital for Sick Children, Toronto, Ontario, Canada
- Brooke, Josefina A., The Hospital for Sick Children, Toronto, Ontario, Canada
- Dhillon, Vaneet, The Hospital for Sick Children, Toronto, Ontario, Canada
- Licht, Christoph, The Hospital for Sick Children, Toronto, Ontario, Canada
- McKay, Ashlene Maree, The Hospital for Sick Children, Toronto, Ontario, Canada
- Pearl, Rachel Jane, The Hospital for Sick Children, Toronto, Ontario, Canada
- Teoh, Chia Wei, The Hospital for Sick Children, Toronto, Ontario, Canada
- Vasilevska-Ristovska, Jovanka, The Hospital for Sick Children, Toronto, Ontario, Canada
- Parekh, Rulan S., Women's College Hospital, Toronto, Ontario, Canada
Background
Acute mercury toxicity can cause nephrotic syndrome in children and adults. It is unknown if chronic exposure to toxic metals is a risk factor for childhood nephrotic syndrome. Our aims were to evaluate the association of toxic metal exposure and longitudinal outcomes among children with nephrotic syndrome.
Methods
We analyzed data from INSIGHT, a prospective childhood nephrotic syndrome cohort. We included children (1-18 years) with nephrotic syndrome diagnosed from 2001-2019 from the Greater Toronto Area, Canada. Toenail clippings were collected and tested for total mercury, copper, arsenic, selenium, cadmium, tin, and lead concentrations. We evaluated associations between individual and mixed metal concentrations and relapse rate, steroid resistance, frequent relapses, and steroid-sparing medication use.
Results
Nails were analyzed from 298 children with nephrotic syndrome. Median age at diagnosis was 4 years (IQR 3-6), 183 (63%) were male, 104 (36%) were South Asian, and 17 (6%) were steroid resistant. Less than 1% had elevated nail mercury and 10% had other elevated metal concentrations. None had metal concentrations in a potentially toxic range. There were no significant associations between nail mercury concentration and nephrotic syndrome relapses (RR 1.05, 95%CI 0.96-1.14), steroid resistance (OR 0.90, 95%CI 0.59-1.32), frequent relapses or steroid dependence (OR 1.01, 95%CI 0.83-1.24), or steroid-sparing medication use (OR 1.12, 95%CI 0.92-1.35). Concentrations of other individual or combined metals were also not associated with outcomes.
Conclusion
High exposure to mercury and other toxic heavy metals is rare among children with nephrotic syndrome. Findings suggest that chronic exposure to toxic heavy metals is not associated with nephrotic syndrome outcomes.
Figure. Correlation between nail mercury concentration and relapse rate