Mosul Journal of Nursing

Background and objectives: Chronic kidney disease (CKD) is a common problem in public health. Its prevalence has been studied using the estimated glomerular filtration rate (eGFR) by the creatinine-based equations developed in Modified Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) study. Recently, new equations based either on cystatin C alone (Cystatin C₁) or cystatin C with the age (Cystatin C₃), or estimating equation including all of Cystatin C, serum creatinine and age (Cystatin C₄) have been proposed by the CKD-Epidemiology collaboration. The aim of this study was to measure the differences between these estimating equations to achieve the closest one to the gold standard 24 hours corrected creatinine clearance (Corrected CrCl).
 
Methods: Corrected 24 hours urine creatinine clearance from 185 patients with different stages of CKD was compared with eGFR derived from six equations which are Cockcroft–Gault (CG), (4-MDRD), CKD-EPI, Cystatin C4, Cystatin C3, Cystatin C1 equations, the results were analyzed using Receiver Operating Characteristics Curve (ROC) and correlation analysis by SPSS computerized statistical analysis program.
 
Results: the result revealed depending on corrected 24h creatinine clearance as a gold standard that the most accurate eGFR equation was in the following order Cystatin C1 and Cystatin C3, Cytatin C4, CKD-EPI, 4MDRD, then Cockcroft–Gault respectively.
Conclusions: Cystatin C dependent eGFR equations are good, reliable, simple and accurate method for estimating renal functions.
Recommendations: Physician involved in diagnosis and treatment of patients with kidney diseases are better to be advised to use Cystatin C eGFR equations rather than the other previously known eGFR equations which were less accurate.