ABSTRACT Background: Kidney disease, even when mild, was once considered so major an impediment to successful pregnancy and so dangerous to the mother’s wellbeing. High-risk pregnancy mainly associated to renal impairment may occur in 10-20% of gestations and it is very important that renal function is closely monitored to prevent or minimize maternal and fetal complications. This study was designed to investigate the performance of Cockcroft-Gault CGeq and the simplified MDRDeq equations in healthy pregnant women to assess renal function. Methods: We studied 167 normal ambulatory pregnant women and kidney function was contemporaneously estimated through the CGeq and the simplified MDRDeq and calculated through the creatinine clearance (Ccr). Serum and urinary creatinine were assayed using Jaffé reaction method in the same AutoAnalyser. Results: When we compared calculated and estimated clearences for measurement of kidney function we observed that CGeq overestimated renal function (CGeq = 168.41 ± 38.80 ml/ min/1.73 m2, Ccr = 146.27 ± 30.49 ml/min / 1.73 m2, p < 0.001), MDRDeq underestimated renal function (Ccr = 146.27 ± 30.49 ml/min / 1.73 m2, MDRDeq = 129.15 ± 29.28 ml/min / 1.73m2, p < 0.001). Conclusions: Our results demonstrated that CGeq overestimated, MDRDeq underestimated significantly kidney function during gestation in healthy women and cannot be recommended to assess renal function in obstetric practice. Ccr remains a useful clinical tool in pregnant women until the development of a specific equation that considers the several important maternal renal physiological alterations and provides the measure of GFR the most unbiased and precise as possible.
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nullMarques, L. , Rocco, R. , Victor, M. , Novaes, B. , Carvalho, A. and Santos, O. (2011) Clinical use of estimating glomerular filtration rate equ-ations during pregnancy. Health, 3, 32-36. doi: 10.4236/health.2011.31006.
 Umans, J.A., Lindheimer, M.D. (1995) The renal adaptations to pregnancy is now nostalgic. Journal of Clinical Investigation, 96, 482-490. doi:10.1172/JCI118048
Conrad, K. (2004) Mechanisms of renal vasodilation and hiperfiltration during pregnancy. Journal of the Society for Gynecologic Investigation, 7, 438-443.
ACOG practice bulletin. (2002) Diagnosis and management of preeclampsia and eclampsia. Obstetrics Gynecology, 99, 159-166.
Levey, A.S., Eckardt, K.U., Tsukamoto, Y., et al. (2005) Definition and classification of chronic kidney disease (KDIGO). Kidney international, 67, 2089-2010.
National Kidney disease education program: Information for health professionals (2004) National Institutes of Health, National Institutes of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, USA.
Shemesh, O., Golbetz, H., Kriss, J.P. and Myers, B.D. (1985) Limitations of creatinine as a filtration marker in glomerulopathic patients. Kidney Internation, 28, 830-838. doi:10.1038/ki.1985.205
Johnson, D.W. (2005) Use of serum creatinine concentration to assess level of kidney function. Nephrology, 10, s133-s139. doi:10.1111/j.1440-1797.2005.00487_1.x
Cockcroft, D.W., Gaul,t M.H. (1976) Prediction of creatinine clearance from serum creatinine. Nephron, 16, 31-41. doi:10.1159/000180580
Levey, A.S., Green, T., Kusek, J.W., et al. (2000) A simplified equation to predict glomerular filtration rate from serum creatinine. Journal of the American Society Nephrology, 11, 151A.
Stevens, L.A., Schmid, C.H., Greene, T., et al. (2009) Factors other than GFR affect serum cystatin levels. Kidney international, 75, 652-660.
Akbari, A., Lepage, N., Keely, E., Clark, H.D., Jaffey, M. and Filler, G. (2005) Cystatin C and beta trace protein as markers of renal function in pregnancy. British Journal of Obstetrics Gynecology, 112, 575-578.
Jeyabalan, A. and Conrad, K.P. (2007) Renal function during normal pregnancy and preeclampsia. Front Bioscience, 12, 2425-2437. doi:10.2741/2244
Miller, W.G., Myers, G.L., Ashwood, E.R., et al. (2005) Creatinine measure: state of the art in accuracy and inter-laboratory harmonization. Archives Pathology & Laboratory Medicine, 129, 297-304.
Delemarre, F.M. and Schoenmakers, C.H. (2008) The MDRD formula in pregnancy. BJOG, 115, 1192.
Marques, L.P.J., Rocco, R., Victor, M.H., Novaes, B.C., Carvalho, A.L.B. and Santos, O.R. (2009) Clinical using of estimating glomerular filtration rate equations during pregnancy. World Congress of Nephrology, Milan Italy, 22-26 May 2009, poster Su. 197.
C?té, A.M., Lam, E.M., von Dadelszen, P., Mattman, A., Magee, L.A. (2010) Monitoring renal function in hypertensive pregnancy. Hypertens Pregnancy, 29, 318-29.
Alper, A.B., Yi, Y., Webber, L.S., Pridjian, G., Mumeney, A.A., Saade, G., Morgan, J., Nuwayhid, B., Belfort, M. and Puschett, J. (2007) Estimation of glomerular filtration rate in preeclamptic patients. American Journal of Perinatology, 24, 569-574. doi:10.1055/s-2007-986697
Geddes, C.C., Woo, M.Y. and Brady, S. (2008) Glomerular filtration rate – What is the rationale and justification of normalizing GFR for body surface area? Nephrol Dial Transplant, 23, 4-6. doi:10.1093/ndt/gfm662
Stevens, L.A., Coresh, J., Deysher, A.E. and Levey, A.S. (2007) Evaluation of the MDRD study equation in a large diverse population. Journal of the American Society Nephrology, 18, 2749-2757.
Froissart, M., Rossert, J., Jacquot, C., et al. (2005) Predictive performance of the MDRD and Cockcroft- Gault equations for estimating renal function. Journal of the American Society Nephrology, 16, 763-773.
Smith, M., Moran, P., Ward, M.K., Davison, J.M. (2008) Assessment of glomerular filtration rate during pregnancy using the MDRD formula. BJOG, 115, 109-112.
Ahmed, S.B., Bentley-Lewis, R., Hollenberg, N.K., Graves, S.W., Seely, E.W. (2009) A comparison of prediction equations for estimating glomerular filtration rate in pregnancy. Hypertens Pregnancy, 28, 243-55.