Classification of hepatitisIn the new classification system of Hepatitis, Grading refers to the assessment of necroinflammatory activity. Chronic hepatitis represents a series of liver disorders of varying causes and severity in which hepatic inflammation and necrosis continue for at least 6 months. Earlier chronic hepatitis was categorized into three types depending upon histopathological features. These areChronic persistent hepatitis Chronic lobular hepatitis Chronic active hepatitisNow, this categorization has been replaced by more informative classification based upon a combination of clinical serological and histological variables. Now the classification is based upon —It's cause Its histologic activity or grade It's a degree of progression or stage(a) Classification by cause —In this, the hepatitis is classified according to the cause - such as viral hepatitis, autoimmune hepatitis, drug-associated hepatitis.(b) Classification by Grade —This classification is based upon an assessment of necroinflammatory activity. An assessment of following histological features is made on liver biopsy - Periportal necrosis Piecemeal necrosis Bridging necrosis Portal inflammation(c) Classification by stage —This classification is based upon the degree of fibrosis. It reflects the levels of progression of the disease. Staging is based upon the degree of fibrosis as follows0 = No fibrosis 1= Mild fibrosis (limited to portal tract) 2 = Moderate fibrosis (Portal and periportal fibrosis) 3 = Severe fibrosis including bridging fibrosis 4 = Cirrhosis