Autoimmune hepatitis, one disease with many faces: Etiopathogenetic, clinico-laboratory and histological characteristics

Table 3 Simplified criteria for the diagnosis of autoimmune hepatitis

Feature/parameter	Discriminator	Score
ANA or SMA +	≥ 1:40	+11
ANA or SMA+	≥ 1:80	+21
or LKM +	≥ 1:40	+21
or SLA/LP +	Any titer	+21
IgG or γ-globulins level	> upper limit of normal	+1
	> 1.1 × upper limit	+2
Liver histology (evidence of hepatitis is a necessary condition)	Compatible with AIH	+1
	Typical of AIH	+2
	Atypical	0
Absence of viral hepatitis	No	0
	Yes	+2

¹Addition of points achieved for all autoantibodies (maximum, 2 points). Definite autoimmune hepatitis: ≥ 7; Probable autoimmune hepatitis: ≥ 6. Typical liver histology for autoimmune hepatitis = each of the following features had to be present, namely interface hepatitis, lymphocytic/lymphoplasmocytic infiltrates in portal tracts and extending into the lobule, emperipolesis (active penetration by one cell into and through a larger cell) and hepatic rosette formation. Compatible liver histology for autoimmune hepatitis = chronic hepatitis with lymphocytic infiltration without all the features considered typical. Atypical = showing signs of another diagnosis, like steatohepatitis. ANA: Antinuclear antibodies; SMA: Smooth muscle autoantibodies; LKM: Liver/kidney microsomal; SLA/LP: Soluble liver antigen or liver pancreas; AIH: Autoimmune hepatitis.