The definition and diagnostic criteria of Acute-on-chronic liver failure (ACLF) has been well established by EASL CANONIC study. However, patients with high risk to develop ACLF has not been determined, yet. The aim of current study is to establish a preliminary pre-ACLF definition, and to demonstrate the corresponding risk factors.

Inclusion Criteria:

1. Chronic hepatitis B virus infection;
2. Any of the followings: Alanine aminotransferase (ALT)≥3 upper limit of laboratory reference (ULN); Aspartate aminotransferase (AST)≥3 ULN; Serum bilirubin≥2 ULN; Acute decompensation (ascites, hepatic encephalopathy, variceal hemorrhage and/or bacterial infections)

Exclusion Criteria:

1. Previous decompensation;
2. those who had hepatocellular carcinoma or other types of malignancies;
3. those who combined with severe chronic extra-hepatic disease;
4. pregnant;
5. received liver transplantation or kidney transplantation before or after admission;
6. readmission;
7. death within 24 hours.

Patients with HBV-related compensated liver disease and acute liver injury or decompensation.