Modification of the Schwartz equations for children increases their accuracy at eGFR %26gt; 60mL/min/1.73m(2)

作者：Zachwieja Katarzyna; Korohoda Przemyslaw; Kwinta Rybicka Joanna; Miklaszewska Monika; Moczulska Anna; Bugajska Jolanta; Berska Joanna; Drozdz Dorota; Pietrzyk Jacek A

来源：Renal Failure, 2016, 38(5): 787-798.

DOI：10.3109/0886022X.2016.1163152

• Children
• CKD
• GFR calculation
• GFR equations
• iohexol test

Aim: Estimation of eGFR in children with normal kidney function using the Schwartz equations results in underestimating real GFR. Materials and methods: We propose modification of three Schwartz equations - two based on creatinine concentration (eGFRScrBS bedside) and (eGFRScr) and one 3-marker based on creatinine, urea and cystatin C concentrations (eGFRS3M). The iohexol test (reference method) was performed 417 times in 353 children >2 years with mean GFR: 98 +/- 31.6ml/min/1.73m(2). The assessment included also the Filler and Zappitelli equations. The modification was performed using methods: (1) based on equation, eGFR(cor)=a [eGFR - T] + T, where T=50, if eGFR>T, and a equals for: eGFRScrBS 1.4043, for eGFRScr 2.0048, for eGFRS3M 1.2951, and (2) based on correction of all coefficients of the original equation. Results: For comparison of all the results and for children with GFR<60, 60-90, 90-135 and >135ml/min/1.73m(2) the correlation coefficient, relative error (RE) and root mean square relative error (RMSRE) was employed and revealed improvement of RE from 25.9 to 6.8 and 3.9% (depending on the correction method) for eGFRScr; from 19 to 8.1 and 3.9% for eGFRScrBS and: from 11.6% to 2.0 and 2.3% for eGFRS3M (respectively). The RMSRE values changed from 30 to 21.3 and 19.8% for eGFRScr, from 25.1 to 21.6 and 19.8% for eGFRScrBS and from 19.1 to 15.8 and 15.3 % for eGFRS3M. Conclusions: Modifications of Schwartz equations at GFR>60ml/min/1.73m(2) significantly improves the accuracy of calculating eGFR. The 3-markers equation is more accurate and should be employed frequently.

• 出版日期2016-6