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

Background/Aims

Accurate assessment of renal function in patients with liver cirrhosis is difficult and of great prognostic importance. The present study aimed to determine the prognostic significance of certain renal markers and to investigate the priority of serum cystatin C (CysC) levels on one-year mortality in cirrhotic patients.

Methods

Renal function of 45 liver cirrhotic patientss was evaluated by levels of blood urea nitrogen (BUN), serum creatinine (Cr), CysC, as well as 24-hour creatinine clearance (CCl) and estimated glomerular filtration rate obtained by Cockroft-Gault and MDRD formulas. The endpoint of the follow up was mortality within one year. Spearman’s correlation, linear regression analysis and receiver operating characteristic curves were used to investigate prognostic factors.

Results

42 men and 3 women (mean age 53.18 ± 9.71 years) were enrolled in the study. Eleven of the patients (24.4%) died as a result of liver cirrhosis within one year. In predicting mortality, levels of BUN, serum Cr and CysC showed area under the curves (AUC) values of 0.719 (95% CI, 0.539–0.899, p = 0.03), 0.726 (95% CI, 0.541–0.911, p = 0.026) and 0.770 (95% CI, 0.620–0.920, p = 0.008). Sensitivity and specificity of a CysC level of >1.3 mg/l in predicting mortality were 72% and 68%, respectively. Univariate regression analysis showed that elevated levels of CysC above the referent ones, increased the risk of one-year mortality nearly six times (p = 0.02, Exp (B) = 5.81).

Conclusions

Serum CysC could be used as a good prognostic marker in patients with cirrhosis and normal Cr levels.