Cirrhosis is a common digestive system disease and represents the final stage of the progression of various chronic liver diseases. During cirrhosis, the intestinal microenvironment is affected due to liver damage and increased portal venous pressure. Displacement of gut microbiota is closely related to the occurrence and development of cirrhosis. Disruption of the gut microbiota is associated with changes in the levels of nitric oxide (NO), hydrogen (H₂), methane (CH₄), and hydrogen sulfide (H₂S). Breath testing is an emerging method for assessing gut microbiota. This project aims to investigate the characteristics and prognosis of patients with chronic liver disease by detecting exhaled breath markers such as nitric oxide (NO), hydrogen (H₂), methane (CH₄), and hydrogen sulfide (H₂S), in conjunction with results from serological tests, gut microbiota analysis, and radiomics. The goal is to identify new diagnostic biomarkers and therapeutic targets, to recognize high-risk patients at an early stage, and to improve patient survival rates and quality of life.

Inclusion Criteria:

① Patients diagnosed with chronic liver disease or cirrhosis through liver biopsy pathology or clinical laboratory and imaging examinations;

② Undergo molecular breath testing within one week of admission.

Exclusion Criteria:

• Patients who have received antibiotic treatment within one month; ② Patients with severe pulmonary diseases, such as chronic obstructive pulmonary disease (COPD), asthma, or lung malignancies that have not been clinically cured; ③ Patients who are unable to successfully complete the molecular breath test.

Patients with chronic liver disease and cirrhosis hospitalized at Fudan University Affiliated Zhongshan Hospital, Shanghai Institute of Geriatric Medicine, and Minhang District Central Hospital.