Pediatric Nephrology

, Volume 6, Issue 6, pp 507–511

Creatinine for estimation of glomerular filtration rate

  • Stanley Hellerstein
  • Uri Alon
  • Bradley A. Warady
Original Article

DOI: 10.1007/BF00866485

Cite this article as:
Hellerstein, S., Alon, U. & Warady, B.A. Pediatr Nephrol (1992) 6: 507. doi:10.1007/BF00866485

Abstract

The aim of this study was to evaluate the plasma creatinine concentration (PCr) and creatinine clearance (CCr) for estimation of glomerular filtration rate (GFR). Inulin clearance (Cin) was used as the reference standard for GFR. Thirty-nine concurrentCin andCCr studies provided data for comparingCin with the measuredCCr and with the calculatedCCr (calc-CCr). (Calc-CCr=k·L/PCr, where L=height in centimeters and k is the proportionality constant.) Thirty-one children 5.3–20.8 years of age, withCin ranging from 2.8 to 138.8 ml/min per 1.73 m2, participated in these studies at The Children's Mercy Hosptial. The measuredCCr was 16.7±10.3 ml/min per 1.73 m2 (P<0.001) greater than theCin, and the calc-CCr overestimatedCin by a mean of 31.6±20.8 ml/min per 1.73 m2 (P<0.001). Although there is good correlation betweenCin andCCr (r=0.96), andCin and calc-CCr (r=0.90), the 95% confidence intervals are quite broad. Hence, theCCr and the calc-CCr, derived using Schwartz values for k, consistently overestimate GFR. However, if the k value in the equation GFR=k·L/PCr is derived from k=Cin/L, rather than from k=CCr·PCr/L, a more accurate estimate of GFR may be obtained.

Key words

Glomerular filtration rateInulin clearanceCreatinine clearancePlasma creatinineCalculated creatinine clearance

Copyright information

© IPNA 1992

Authors and Affiliations

  • Stanley Hellerstein
    • 1
    • 2
  • Uri Alon
    • 1
    • 2
  • Bradley A. Warady
    • 1
    • 2
  1. 1.Department of PediatricsUniversity of Missouri-Kansas City School of MedicineKansas CityUSA
  2. 2.Section of Pediatric NephrologyThe Children's Mercy HospitalKansas CityUSA