Abstract: Objective To investigate the prognostic efficacy of serum keratin 18 in patients with hepatitis B virus-related acute on chronic liver failure（HBV-ACLF）. Methods One hundred patients with HBV-ACLF,30 with chronic hepatitis B and 30 healthy persons were recruited in our hospital between January 2015 and January 2017,and serum K18 （M30 and M65） levels were measured by enzyme-linked immunosorbent assay. All patients were followed-up for 3 months. The prognostic efficacy of M30/M65 ratio and the end stage liver disease model（MELD） were assessed by AUC. Results Serum M30,M65 and M30/M65 ratio in patients with ACLF at presentation were（1.0±0.1） lg U/L,（3.4±0.3） lg U/L and （0.3±0.1）,significantly different as compared to 【（2.1±0.1） lg U/L,（3.3±0.2） lg U/L and （0.6±0.0）,respectively,P<0.05】 in patients with CHB or【（2.1±0.1） lg U/L,（2.1±0.1） lg U/L and（1.0±0.2）,respectively,P<0.05】 in control persons;MELD score in 68 survivals was（18.2±.0）,significantly lower than【（26.1±3.3）,P<0.05】 in 32 dead,serum M65 level was [（2.9±0.2） lg U/L,much lower than [（4.1±0.5） lg U/L,P<0.05] in the dead,and M30/M65 ratio was （0.4±0.1）,significantly higher than 【（0.2±0.1）,P<0.05】 in the dead group;the cut-off-value of MELD in forecasting the prognosis of patients with ACLF was 23.21,and its AUC was 0.650,with the sencitivity（Se） of 85.5%,specificity（Sp） of 65.0% and accuracy （Ac） of 72.0%,while the cut-off-value of M30/M65 ratio was 0.30,and its AUC was 0.875,with the Se of 94.5%,Sp of 85.0% and Ac of 85.0%,much superior to MELD score（P<0.05）. Conclusion Serum K18（M30 and M65） level is related to the severity of liver diseases,and early detection of serum M30/M65 might be helpful in predicting the prognosis of patients with HBV-ACLF.

Key words: Acute-on-chronic liver failure, Serum keratin 18, Prognosis