A study of glomerular filtration rate estimation by cockcroft-gault, mdrd and ckd-epi formula in comparison with dtpa renal scan – a comparative study among live related kidney donors in south india.

Abstract

ABSTRACT BACKGROUND: Renal function assessment is the most important part of donor evaluation. The Glomerular Filtration Rate (GFR) is considered to be optimal test for overall assessment of renal function. We aimed to estimate GFR by prediction equations namely COCKCROFT-GAULT, MDRD and CKD-EPI, among live related kidney donors and to analyse how closely the GFR calculated by these equations correlate with that of DTPA renal scan. MATERIALS AND METHODS: A total of 50 individuals attending Nephrology OPD over a period of 6 months (April 2011- September 2011), for undergoing donor evaluation at the Department of Internal Medicine and the Department of Nephrology, Government Stanley Medical College and Hospital, Chennai, India, were included. They underwent basic investigations and GFR was estimated using prediction equations namely COCKCROFT-GAULT, MDRD and CKD-EPI. Then as a part of routine donor evaluation, they were subjected to DTPA renal scan. RESULTS: In our study on 50 potential donors, all the three prediction equations namely COCKCROFT-GAULT, MDRD and CKD-EPI were found to correlate with DTPA scan values, the correlation though weak, was statistically significant for MDRD and CKD-EPI, and statistically not significant for COCKCROFT-GAULT equation. However they underestimated GFR by 27.65%, 27.17% and 22.42% for COCKCROFT-GAULT, MDRD and CKD-EPI respectively when compared to DTPA renal scan. CONCLUSION: DTPA scan cannot be substituted by the GFR prediction equations in special situations like renal transplantation. Further studies are required to find newer ways of estimating GFR which can be applied in all clinical settings.