Estimation of Glomerular Filtration Rate Based on Serum Cystatin C versus Creatinine in a Uruguayan Population

Abstract

Background. Estimation of glomerular filtration rate (eGFR) from biomarkers has evolved and multiple equations are available to estimate renal function at bedside. Methods. In a random sample of 119 Uruguayans (54.5% women; 56.2 years (mean)), we used Bland and Altman's method and Cohen's kappa statistic to assess concordance on a continuous or categorical (eGFR < 60 versus ≥60 mL/min/1.73 m2) scale between eGFRcys (reference) and eGFR derived from serum creatinine according to the Modification of Diet in Renal Disease (eGFRmdrd) or the Chronic Kidney Disease Epidemiology Collaboration equations (eGFRepi) or from both serum cystatin C and creatinine (eGFRmix). Results. In all participants, eGFRmdrd, eGFRepi, and eGFRmix were, respectively, 9.7, 11.5, and 5.6 mL/min/1.73 m2 higher (P < 0.0001) than eGFRcys. The prevalence of eGFR <60 mL/min/1.73 m2 was the highest for eGFRcys (21.8%), intermediate for eGFRmix (11.8%), and the lowest for eGFRmdrd (5.9%) and eGFRepi (3.4%). Using eGFRcys as reference, we found only fair agreement with the equations based on creatinine (Cohen's kappa statistic 0.15 to 0.23). Conclusion. Using different equations we reached clinically significant differences in the estimation of renal function. eGFRcys provides lower estimates, resulting in higher prevalence of eGFR <60 mL/min/1.73 m2.

Establishing the presence or absence of chronic kidney disease: Uses and limitations of formulas estimating the glomerular filtration rate

“…A Scandinavian study found a substantially different prevalence of CKD with the use of the MDRD formula than with the use of the Cockroft-Gault formula or of two cystatin-based equations[ 123 ]. Similar findings were reported in a study from Uruguay, in which the lowest values of eGFR were found when using the CKD-EPI cystatin C equation, while the CKD-EPI creatinine-cystatin formula computed intermediate eGFR values and the MDRD formula computed the highest values of eGFR[ 129 ]. A study in Asian Indians, which also found lower overall eGFR values when using cystatin-based equations, noted that these equations resulted in widely varying eGFR values which affected the classification of CKD[ 130 ].…”

Protective role of apple cider vinegar (APCV) in CCl4-induced renal damage in wistar rats

“…It is the by-product of creatine phosphate in muscle, and is produced at a constant rate by the body. In most cases, creatinine is cleared from the blood entirely by the kidney and it is the most commonly used endogenous marker for assessment of glomerular function [ 12 ]. Clinically, estimate of the glomerular filtration rate (GFR) remains the most practical means of assessing renal function.…”

“…GFR is the rate (mm/min) at which substances are filtered or cleared from the blood through the kidney glomerulus. Serum creatinine level is elevated when there is a significant decline in the glomerular filtration rate [ 12 ]. The normal physiological range for serum creatinine though varies with age, gender and muscle mass, is usually 0.5–1.2 mg/dL or 44–106 μmol/L (SI units) [ 10 ].…”

<p>Early Detection of Renal Impairment Among Patients with Type 2 Diabetes Mellitus Through Evaluation of Serum Cystatin C in Comparison with Serum Creatinine Levels: A Cross-Sectional Study</p>

“…Our finding was similar to other studies. 10,18 We also calculated the serum cystatin C derived eGFR equation and found that, 29 (48.3%) of the T2DM patients were normal or elevated GFR (≥90 mL/ min/1.73 m 2 ), 18 (30%) of the patients were in stage 2 CKD with mild GFR reduction (GFR=60-89 mL/min/ 1.73 m 2 ), 11 (18.4%) of the patients were in stage 3 with moderate decreased GFR (GFR=30-59 mL/min/1.73 m 2 ), and two (3.3%) patients were in stage 4 with severe GFR reduction (GFR=15-29 mL/min/1.73 m 2 ). Based on eGFR using both serum cystatin C-creatinine Eq, 41 (68.…”