Abstract: SA-PO0707
Pediatric Reference Ranges for Urinary Tubular Injury Biomarkers Normalized to Creatinine
Session Information
- Pediatric Nephrology: Transplantation, Hypertension, AKI, Genetics, and Developmental Diseases
November 08, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Pediatric Nephrology
- 1900 Pediatric Nephrology
Authors
- Mohan, Shruthi, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States
- Devarajan, Prasad, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States
- Nehus, Edward, Charleston Area Medical Center, Charleston, West Virginia, United States
Background
We aimed to establish pediatric reference values for urinary tubular injury biomarkers normalized to creatinine (Cr)-neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), interleukin-18 (IL-18), and liver fatty acid-binding protein (L-FABP) and assess whether Cr normalization reduces biological variability.
Methods
We analyzed data from 367 healthy children. Biomarker concentrations were normalized to Cr, and associations with age and sex were assessed using linear regression.
Results
Median [IQR] values for urinary biomarkers normalized to Cr were: NGAL: 5.9 [2.8–14.8] ng/mg, KIM-1: 360.1 [234.9–551.0] pg/mg, IL-18: 20.3 [12.7–29.5] pg/mg, and LFABP: 2.8 [1.5–5.4] ng/mg. Age-related decreases were observed for KIM-1/Cr (−3.5%/year), IL-18/Cr (−4.9%/year), and LFABP/Cr (−10.2%/year) (all p < 0.001); NGAL/Cr showed no association with age. Females had higher NGAL/Cr (256%) and IL-18/Cr (68%) than males (both p < 0.001); Single sex-specific thresholds for elevated NGAL/Cr were established: 80 ng/mg (females) and 15 ng/mg (males). Figure 1 shows normalized urinary biomarker concentrations by age and sex; Table 1 shows 95th percentile cutoffs. Urinary Cr was independently associated with biomarker concentrations after adjusting for age and sex (p < 0.001); squared partial correlation coefficients were: NGAL, 0.21; KIM-1, 0.54; IL-18, 0.48; LFABP, 0.30.
Conclusion
Normalization decreases biologic variability and may therefore improve the detection of abnormal values in conditions with steady state urinary Cr values such as chronic kidney disease.
Funding
- NIDDK Support