Serum cystatin C level is a good prognostic marker in patients with cirrhotic ascites and normal serum creatinine levels

Background/Aims Serum creatinine (Cr) is not a reliable marker for early detection of renal dysfunction in patients with cirrhotic ascites. Several reports have suggested that cystatin C (CysC) is more sensitive than Cr for detecting reduced renal function in these patients. This study evaluated the clinical significance of CysC in patients with cirrhotic ascites and a normal serum Cr level. Methods We enrolled patients with ascites and a normal serum Cr level (< 1.2 mg/dl). Liver function tests, international normalized ratio (INR) and serum Cr and CysC levels were measured on the same day for all patients. CysC levels were measured using the automated latex-enhanced immunonephelometric method. The endpoint of follow-up was the development of hepatorenal syndrome (HRS) or mortality. Results Seventy-eight patients with cirrhotic ascites were enrolled in the study (58 men and 30 women; age, 53 +/- 11 years). The underlying liver diseases in these patients were chronic hepatitis B (37%), chronic hepatitis C (4%), alcoholic liver disease (53%) and others (6%). Forty-six (59%) and 32 (41%) patients were in Child-Pugh classes B and C respectively. HRS developed in 14 patients during the follow-up period (349 +/- 241 days), with cumulative incidences of 10.2% and 20.4% at 6 and 12 months respectively. The CysC level was the only independent predictive factor for HRS. Twenty-three patients died during the follow-up period. CysC level and INR were independent factors for predicting mortality. Conclusion Serum CysC level is a good marker for predicting HRS and survival in patients with cirrhotic ascites and a normal Cr level.