Abstract: Objective The purpose of this study was to investigate urine retinol binding protein (RBP) levels in patients with hepatitis B-induced decompensated liver cirrhosis (LC) as the index for acute kidney injury (AKI). Methods 112 patients with decompensated hepatitis B liver cirrhosis and 35 healthy individuals were recruited in our hospital between May 2015 and May 2018,and urine RBP levels were detected by ELISA. The diagnostic efficacy of urine RBP for AKI was evaluated by area under the ROC (AUC). Results Urine RBP level in patients with decompensated cirrhosis was (2.2±1.0) mg/L, significantly higher than in healthy persons; urinary RBP, urinary microalbumin (mAlb) and estimated glomerular filtration rate (eGFR) in 28 patients with severe ascites were (3.2±0.6) mg/L, (24.9±7.7) mg/L and (58.3±13.9) mL/min/1.73 m², among them, the urinary RBP and urinary mAlb levels were significantly higher than those in the 31 mild ascites or 53 moderate ascites, and the eGFR level was significantly lowerthan that in patients with mild ascites or moderate ascites, with thedifferences were statistically significant (P<0.05); there was no significant difference as respect to sCr level between patients with severe ascites and moderate ascites , but they were much higher than that in mild ascites ; univariate analysis showed that there were no significant differences in platelet counts and upper gastrointestinal bleeding between 43 patients with secondary AKI and 69 without (P>0.05); there were significant differences in mAlb, eGFR, RBP, blood sodium, serum bilirubin, white blood cell counts, prothrombin time activity, NH3⁺, hepatic encephalopathy and spontaneous bacterial peritonitis between the two groups (P<0.05); the AUC of urine RBP in the diagnosis of AKI was 0.856 (95% CI: 0.777-0.915), with the cut-off-value of 2.6 mg/L, sensitivity of 81.4% and specificity of 84.1%. Conclusion Urine RBP level might be used to diagnose AKI as it reflect the severity of ascites in patients with decompensated liver cirrhosis.

Key words: Liver cirrhosis, Retinol-binding protein, Acute kidney injury, Diagnosis