Figure 2.

Histological features of A-AIH and C-AIH. A-AIH (A1–4) and C-AIH (C1–4): A1, C1: A1 shows multiacinar and centrilobular necrosis in A-AIH, which is uncommon in C-AIH (H&E, ×200, small pictures emphasized the typical areas in the big pictures); A2, C2: the main manifestation of A-AIH is cellular swelling, ballooning change, and lobular inflammation accompanied by mild interface inflammation; however, C-AIH often has moderate-to-severe interface inflammation caused by lymphoplasmacytic infiltration (H&E ×200); A3, C3: CK7 staining showing regeneration of cholangiocytes due to the multiacinar necrosis of hepatocyte in A-AIH. However, bile duct regeneration was less likely to be found in C-AIH (CK7, ×200); A4, C4: blue staining shows fibrosis in the portal area; fibrous septa were found in the chronic group but not the acute group (Masson trichrome staining, ×200).