Evaluation of serum cystatin C concentration as a marker of renal function in patients with cirrhosis of the liver

Abstract

Background and aims: Diagnosis of moderately impaired renal function is of particular importance in patients with cirrhosis of the liver. Whereas patients with a markedly impaired glomerular filtration rate can be diagnosed easily by elevated serum creatinine concentrations, moderately reduced renal function may be missed by this conventional parameter. Recently, cystatin C has been suggested as a sensitive marker of renal function, independent of sex or muscle mass. Therefore, the aim of this study was to investigate the value of serum cystatin C concentration for the detection of moderately impaired renal function. Methods: Ninety seven inhospital patients with cirrhosis and a 24 hour creatinine clearance of at least 40 ml/min were investigated and divided into group 1 (creatinine clearance >70 ml/min; n=55) and group 2 (creatinine clearance 40-69 ml/min; n=42). Results: Serum cystatin C concentrations (mean (SD): 1.31 (0.51) v 1.04 (0.34) mg/l (p=0.008)) and creatinine concentrations (1.03 (0.52) v 0.86 (0.22) mg/100 ml (p=0.03)) were higher in group 2 than in group 1; there was no significant difference in urea concentrations. Receiver-operator characteristics (ROC) revealed a differential diagnostic advantage of cystatin C over creatinine and urea. At cut off concentrations of 1.0 mg/l, 0.9 mg/100 ml, and 28 mg/100 ml, respectively, cystatin C, creatinine, and urea exhibited 69%, 45%, and 44% sensitivity (p<0.05). As patients with a small muscle mass or reduced physical activity could be particularly prone to overestimation of their renal function, separate analyses were performed for the subgroups of female and Child-Pugh class C patients, respectively. In both groups, discrimination between patients with moderately impaired and normal renal function was best with cystatin C. In female patients, sensitivity of cystatin C (77.8%) was superior (p<0.05) to that of creatinine (38.9%) and urea (41.2%). In Child-Pugh C patients, the ROC curve was significantly better for cystatin C than for creatinine. Conclusions: Serum cystatin C determination could be a valuable tool in patients with cirrhosis, particularly with Child-Pugh class C or in female patients, for early diagnosis of moderately impaired renal function.

Prognostic value of serum cystatin C levels in cirrhotic patients with normal serum creatinine

“…Ten of these patients (62.5%) had reduced GFR (CCl<80 ml/min/1.73 m 2 ). These results were consistent with previous studies that proved serum CysC to be a better marker of GFR than serum Cr in cirrhotics [12,13]. We used measured CCl as a referent method for determining GFR because it is a reliable and not an expensive method.…”

“…Unlike serum Cr, CysC levels are independent of age, sex, muscle mass, inflammatory conditions or malignancy [4,9,10]. Several reports have suggested that increased CysC levels are more sensitive in detecting renal dysfunction in patients with cirrhosis than increased Cr levels, and that measurement of serum CysC could offer a good alternative to serum Cr for the assessment of renal function in these patients [11][12][13]. Gerbes et al found that serum CysC is more effective in detecting kidney injury in advanced cirrhotic patients than serum Cr [12].…”

“…Several reports have suggested that increased CysC levels are more sensitive in detecting renal dysfunction in patients with cirrhosis than increased Cr levels, and that measurement of serum CysC could offer a good alternative to serum Cr for the assessment of renal function in these patients [11][12][13]. Gerbes et al found that serum CysC is more effective in detecting kidney injury in advanced cirrhotic patients than serum Cr [12]. Kim et al published similar results, reporting CysC as a useful marker for detecting significant renal dysfunction in cirrhotic patients with ascites and normal serum Cr levels [14].…”

Cystatin C: current position and future prospects

“…In a recent study, CysC was the only marker to correlate with measured GFR in all stages of hepatocellular failure (201). In addition, serum cystatin concentrations also appear to be a better marker than creatinine and the Cockcroft equation for the earlier diagnosis of renal disease in end stage liver failure (202). It has also been recommended for the follow-up of renal function after liver transplantation (203).…”

A tale of two markers

“…17 Indeed, recent studies have shown that cystatin C is a better marker of GFR than Scr in many disease states, including advanced liver failure and hepatorenal syndrome. [17][18][19][20][21][22] Currently, two automated assays are available that make determination of serum cystatin C level as easy and convenient as determining Scr. 23,24 In the article by Schück et al, 10 the ability of cystatin C to predict GFR in the posttransplant population was tested.…”