Assessment of estimated glomerular filtration rate based on cystatin C in diabetic nephropathy

Abstract

Introduction: GFR is estimated by using creatinine and cystatin C to determine renal dysfunction. Our aim was to evaluate estimated GFR (eGFR) based on cystatin C in type 2 diabetic patients with diabetic nephropathy (DN). Methods: Study group included 52 controls (46% male, age: 54.5±12.4) and 101 diabetic patients (46.5% male, age: 58.2±11). The diabetics were divided into three subgroups according to 24-hour urine albumin: normal to mildly increased (A1) (n=51), moderately increased (A2) (n=25), severely increased (A3) (n=25) albuminuria. Creatinine clearance (CrCl) was determined. Correlations between CrCl and eGFRs estimated according to the CKD-EPI, MDRD, and Cockcroft-Gault (CG) formulas, and ROC curves were evaluated. Data were analyzed using SPSS 22.0. Results: Only CKD-EPI-cys eGFR was significantly lower in the A1 group than the controls (p=0.021). All GFRs were lower in the A3 group than the control (CKD-EPI-cr, MDRD, CKD-EPI-cys, CKD-EPI-cr-cys: p=0.0001, CG and CrCl: p=0.001) and A1 (for all GFRs p=0.0001) groups. CKD-EPI-cr (p=0.004), MDRD (p=0.01), CG (p=0.037), CKD-EPI-cys (p=0.033), and CKD-EPI-cr-cys (p=0.016) eGFRs in the A2 group were significantly different from the A1 group. All eGFRs showed a moderate correlation with CrCl in the A1group (CKD-EPI-cr and CKD-EPI-cr-cys: r=0.49, p=0.0001, MDRD: r=0.44, p=0.001, CG r=0.48, p=0.0001: CKD-EPI-cys r=0.40, p=0.004). The area under the CKD-EPI-cys ROC curve was the highest and found to be 0.847 (95%CI 0.763-0.931, p=0.0001). Conclusions: Our results showed that the CKD-EPI-cys eGFR can be useful in detecting the early stage of DN and more predictive than the others for prediction of DN.

Diagnostic value of triglyceride and cystatin C ratio in diabetic kidney disease: a retrospective and prospective cohort study based on renal biopsy

“…Studies [ 17 ] have found that dyslipidemia not only promotes glomerulosclerosis and tubulointerstitial damage, but also induces or aggravates renal and external vascular lesions, leading to thromboembolism and other serious complications. Serum Cys-C, a low molecular weight protein, is an endogenous cysteine protease inhibitor and is not affected by inflammation, muscle content, gender, age and other factors [ 18 ]. Serum cystatin C is an ideal indicator of glomerular filtration rate [ 19 ].…”

Measurement and Estimation of Glomerular Filtration Rate in Children With Neurogenic Bladder: A Prospective Study

“…The CKiD Cys C equation is a precise method for estimating eGFR and is closely correlated with tGFR in children with NB. Cys C is a low-molecular-weight protein (an endogenous cysteine proteinase inhibitor) that is freely filtered in the glomerulus and its clearance has a high correlation with GFR 7 . This correlation is independent of muscle mass, body composition, age, and sex 7 .…”

“…Cys C is a low-molecular-weight protein (an endogenous cysteine proteinase inhibitor) that is freely filtered in the glomerulus and its clearance has a high correlation with GFR 7 . This correlation is independent of muscle mass, body composition, age, and sex 7 . Several previous studies have shown that Cys C is a better indicator of GFR in CKD than Scr and other markers, especially in patients with eGFR <60 mL/min/1.73 m 2 .…”

“…Serum creatinine (Scr) and cystatin C (Cys C) are endogenous markers used to estimate GFR 7 . Although Scr is an inexpensive and convenient marker for GFR estimation, it can be affected by age, exercise, muscle mass, and diet 7 .…”

“…Serum creatinine (Scr) and cystatin C (Cys C) are endogenous markers used to estimate GFR 7 . Although Scr is an inexpensive and convenient marker for GFR estimation, it can be affected by age, exercise, muscle mass, and diet 7 . Previous studies have shown that Cys C levels are independent of age and muscle mass, and estimated GFR (eGFR) based on Cys C measurement better correlates with inulin clearance than Scr-based eGFR in the adult population 8,9 .…”