Accurate identification of early DKD in children and adolescents with T1DM depends on reliable estimation of GFR. A study published in Pediatric Nephrology compared widely used eGFR equations with directly mGFR obtained through plasma inulin clearance.

The analysis included 141 youth with a mean age of 13.5 years and an average diabetes duration of 5.7 years. Mean serum creatinine was 45.6 μmol/L, and mean mGFR was 142.3 mL/min/1.73 m², representing a population with preserved kidney function where early detection is critical.

Across the full cohort, the Full-Age Spectrum (FAS-height) equation showed the closest agreement with mGFR, with a bias of 8.37 mL/min/1.73 m² and P30 of 85.1%. The CKiD equation also performed well with a bias of 11.9 and P30 of 81.6%. Subgroup results revealed key differences. In males, the CKiD equation showed the best accuracy, while in adolescents aged 16 to 18.5 years, the Chronic Kidney Disease Epidemiology Collaboration 2009 (CKD-EPI 2009) equation demonstrated minimal bias.

These findings indicate that a single eGFR equation does not fit all youth with T1D. Selecting equations by age and sex may improve early DKD detection and support more precise monitoring.