Elevation of serum cystatin C concentrations in patients with chronic liver disease

Objective We examined serum cystatin C concentrations in patients to explore the possible clinical application of cystatin C as a marker of disease severity in cases of chronic liver diseases. Methods Serum cystatin C concentrations were determined by an enzyme-linked immunosorbent assay kit in 103 patients with various chronic liver diseases and compared with concentrations in healthy control volunteers. Results The mean cystatin C concentration was 0.68 ± 0.03 mg/l in chronic hepatitis patients, 1.13 ± 0.09 mg/l in liver cirrhosis patients and 1.16 ± 0.10 mg/l in hepatocellular carcinoma patients, all significantly higher than concentrations in the control volunteers (P < 0.0001). Significant correlations were observed between cystatin C concentrations and total bilirubin levels, albumin levels, platelet levels, type IV collagen levels and hyaluronic acid levels. Serum cystatin C concentrations correlated well with histological stages despite the lack of correlation with histological grades. Conclusion Our results show that serum cystatin C increases with the progression of chronic liver disease and that it is a potential marker for liver fibrosis.