Patients with Acute on Chronic Liver Failure (ACLF) have high short-term mortality. The use of a severity score could define the patient's prognosis. This study mainly prospectively analyze the clinical data of patients with chronic liver disease related acute liver failure admitted to the department of infectious diseases, Xiangya Hospital of Central South University, to analyze the prognosis of patients with chronic liver disease related acute on-chronic liver failure in Central South China. No additional interventions other than routine treatment will be added.

Patients with Acute on Chronic Liver Failure (ACLF) have high short-term mortality. The use of a severity score could define the patient's prognosis and would help determine in whom the treatment is effective. This study mainly prospectively analyze the clinical data of patients with chronic liver disease related acute liver failure admitted to the department of infectious diseases, Xiangya Hospital of Central South University, to analyze the short-time and relatively long-term prognosis of patients with chronic liver disease related acute on-chronic liver failure. This is an observational study. All subjects will receive the currently recognized routine treatment of liver failure and corresponding etiological treatment if needed. The researchers will collect various clinical examination indexes of the subjects in the process of diagnosis and treatment, including but not limited to blood routine, biochemistry, coagulation function, liver imaging, therapeutic drugs, etc. Complications and prognosis of patients will be recorded. Blood samples, urine and stool samples of all subjects will be taken after enrollment and stored for probably testing in the future. This study has no additional intervention and treatment for subjects. All subjects will sign informed consent.

Inclusion Criteria:

• patients with evidence of chronic liver disease patients with liver failure

Exclusion Criteria:

• Patients who do not have chronic liver disease Patients who have hepatocellular carcinoma Patients who admitted for extrahepatic manifestations Patients who have HIV infection Patients who admitted for symptomatic control of chronic liver disease, other than acute deterioration of liver function

Patient with any cause of chronic liver disease who underwent acute liver dysfunction meets the criteria of ACLF of APASL.