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CKiD U25 eGFR calculator
CKiD U25 eGFR calculator
Age
years
Sex
Height
Serum creatinine
Complete the fields above to see the result.
When to use
- Estimating GFR in children and young adults (age 1-25 years) with chronic kidney disease, including through the transition to young adulthood where the original CKiD bedside equation loses accuracy.
Formula
eGFR = K x height(m) / serum creatinine(mg/dL), with sex-specific constant K = 41.8 (male) or 37.6 (female). This is the constant-K form of the CKiD U25 height/creatinine equation; the original publication also derived an age-refined K and a parallel cystatin-C-based equation not implemented here.
Pearls and pitfalls
- Developed to correct underestimation of GFR by the original 2009 CKiD bedside equation in young children and young adults.
- A cystatin-C-based U25 equation from the same study may be combined with the creatinine-based estimate for improved accuracy.