Score Criterion CA (Cholangitis Activity) 0 (no activity) No cholangitis but mild damage to the bile ducts may be present. 1 (mild activity) One evident chronic cholangitis in the specimen (i.e., nonspecific chronic cholangitis surrounded by mild to moderate lymphoplasmacytic inflammation ). 2 (moderate activity) Two or more bile ducts with evident chronic cholangitis (i.e., nonspecific chronic cholangitis surrounded by mild to moderate lymphoplasmacytic inflammation ). 3 (marked activity) One or more foci of chronic nonsuppurative destructive cholangitis in the specimen (i.e., marked epithelial injury with adjacent marked lymphoplasmacytic inflammation or granuloma; florid duct lesion). HA (Hepatitis Activity) 0 (no activity) No interface hepatitis and no or minimal lobular hepatitis 1 (mild activity)) Interface hepatitis affecting 10 continuous hepatocytes at a limiting plate in 1 portal tract or fibrous septa and mile to moderate lobular hepatitis. 2 (moderate activity) Interface hepatitis affecting 10 continuous hepatocytes at a limiting plate in 2 or more portal tracts or fibrous septa and mile to moderate lobular hepatitis. 3 (marked activity) Interface hepatitis affecting 20 continuous hepatocytes at limiting plates in moree than half of the portal tracts and moderate lobular hepatitis or bridging/zonal necrosis.

Score Criterion Fibrosis 0 No fibrosis or fibrosis limited to portal tracts. 1 Portal fibrosis with periportal fibrosis or incomplete septal fibrosis. 2 Bridging fibrosis with variable lobular disarray. 3 Cirrhosis with regenerative nodules and extensive fibrosis. Bile Duct Loss 0 No bile duct loss. 1 Bile duct loss in less than one-third of portal tracts. 2 Bile duct loss in one-third to two-thirds of portal tracts. 3 Bile duct loss in more than two-thirds of portal tracts. Deposition of Orcein-Positive Granules 0 No deposition of granules. 1 Deposition of granules in a couple of Zone 1 hepatocytes in less than one-third of portal tracts. 2 Deposition of granules in a variable number of Zone 1 hepatocytes in one-third to two-thirds of portal tracts. 3 Deposition of granules in most Zone 1 hepatocytes in more than two-thirds of portal tracts.