Table 2.

Diagnosis and severity of AIH in the Japanese guideline 2013

Diagnosis

1. Exclusion of other, known, specific causes of liver injury

2. Presence of serum ANA or ASMA

3. High serum immunoglobulin G levels (>1.1 times the upper limit of normal)

4. Histological features such as interface hepatitis and/or plasma cell infiltration into the portal area

5. Excellent response to corticosteroid treatment

A typical case should fulfill criterion 1 and at least 3 of the remaining criteria

An atypical case of AIH should fulfill criterion 1 and 1 or 2 of the remaining criteria

Severity

Clinical signs

(1) Hepatic encephalopathy

(2) Reduction or disappearance of hepatic dullness

Clinical laboratory tests

(1) AST, ALT >200 IU/L

(2) Bilirubin >5 mg/dL

(3) Prothrombin time <60%

Imaging tests

(1) Hepatic atrophy

(2) Heterogeneous liver parenchyma pattern

Severe: should fulfill at least 1 of these 3 findings:

1. Clinical signs: (1) or (2) 2. Clinical laboratory tests: both (1) and (3), or both (2) and (3) 3. Imaging tests: (1) or (2)

Moderate: should fulfill these findings:

Clinical laboratory tests: 1 of the criteria [(1), (2), or (3)] or both (1) and (2), without clinical signs [neither (1) nor (2)], and imaging tests [neither (1) nor (2)]

Mild: none of the above criteria are observed

Adapted from the reference paper by Onji et al. [60].