Clinical diagnosis: Those who have a previous history of hepatitis B or HBsAg positive for more than 6 months and are now still positive for HBsAg and/or HBV DNA can be diagnosed with chronic HBV infection. Based on the serology, virology, biochemical tests and other clinical and ancillary findings of HBV-infected patients, chronic HBV infection can be classified as follows 1, HBeAg-positive chronic hepatitis B Serum HBsAg, HBeAg-positive, anti-HBe negative, HBV DNA-positive, persistently or repeatedly elevated ALT, or hepatitis lesions on liver histological examination. 2. HBeAg-negative chronic hepatitis B Serum HBsAg positive, HBeAg persistently negative, anti-HBe positive or negative, HBV DNA positive, ALT persistently or repeatedly abnormal, or hepatitis lesions on liver histological examination. The above two types of chronic hepatitis B can also be further classified as mild, moderate and severe based on biochemical tests and other clinical and ancillary findings. (ii) Hepatitis B cirrhosis. Hepatitis B cirrhosis is the result of the development of chronic hepatitis B. Its pathology is defined as diffuse fibrosis with pseudobullet formation. 1, compensated cirrhosis Generally belongs to Child-Pugh grade A. There is evidence of hepatocyte synthetic dysfunction or portal hypertension (such as hypersplenism and esophagogastric fundic varices) on imaging, biochemistry or hematology, or histology consistent with the diagnosis of cirrhosis, but without serious complications such as ruptured bleeding from esophagogastric varices, ascites or hepatic encephalopathy. 2.Decompensated cirrhosis Generally belongs to Child-Pugh grade B or C. Patients have had serious complications such as ruptured esophagogastric fundic varices bleeding, hepatic encephalopathy and ascites. The compensated and decompensated cirrhosis can also be subdivided into active or quiescent stage. (C), Hepatitis B virus carriers. 1, chronic HBV carriers Mostly HBsAg, HBeAg and HBV DNA positive people in the immune tolerance period, bb more than 3 consecutive follow-ups within 1 year have shown serum ALT and AST in the normal range and no significant abnormalities in liver histological examination. 2. Inactive HBsAg carriers with positive serum HBsAg, negative HBeAg, positive or negative anti-HBe, HBV DNA below the minimum detection limit, more than 3 consecutive follow-ups within 1 year, and ALT all in the normal range. Histological examination of the liver shows that Knodell’s Hepatitis Activity Index (HAI) < 4 or the lesion is judged to be mild according to other semi-quantitative scoring systems. (iv) Occult chronic hepatitis B. Negative serum HBsAg, but positive HBV DNA in serum and/or liver tissue with clinical manifestations of chronic hepatitis B. In addition to HBV DNA positivity, patients may have positive serum anti-HBs, anti-HBe and/or anti-HBc, but about 20% of patients with occult chronic hepatitis B are negative for serologic markers. Diagnosis requires exclusion of other viral and non-viral factors causing liver injury.