Enjoypath

Clinical Futures

Generally progressive, chronic hepatitisof unknown cause that occurs in children and adults of all ages.
The diagnosis is based on: characteristically presence of interface hepatitis on histologic examination, hypergammaglobulinemia, and autoantibodies. There are no features that are absolutely diagnostic, and the existence of the condition can be established only by recognition of a constellation of compatible features and the exclusion of other diseases.
1.9/100,000 persons per year. In US, autoimmune hepatitis affects 100,000 - 200,000 persons, and accounts for 6% of the liver transplantations.
70-80% are women.

Classification

Clinical Features	Type 1	Type 2	Type 3
Diagnostic autoantibodies	ANA, SMA	LKM1	SLA
Other autoantibodies	Anti-actin, pANCA, SLA/LP	ALC-1
Age	Infancy to old age	Children (2-14yo), Rare in adults	Adults (30-50 y)
Women (%)	78	89	90
Concurrent immune disease (%)	41	34	58
Concurrent immune disease	Thyroiditis Graves' disease Ulcerative colitis	Thyroiditis Vitiligo Type 1 diabetes
Gamma globulin elevation	+++	+	++
Low IgA	No	Occasional	No
HLA association	DR3, DR4, B8	B14, Dr3, C4AQO	Uncertain
Steroid response	+++	++	+++
Progression to cirrhosis (%)	45	82	75
ANA: Antinuclear antibodies SMA: Smooth muscle antibody LKM1: Liver kidney microsome type 1 SLA: Soluble liver-kidney antigen		pANCA: Perinuclear antineutrophilic cytoplasmic antibodies SLA/LP: Soluble liver antigen/liver pancreas antigen autoantibody ALC-1: Liver cytosol 1

Antibody (prevalence)	Target antigen	Other disease associations
ANA (60% to 80%)	Multiple nuclear proteins	PBC, PSC, chronic HCV, NAFLD
SMA (60% to 80%)	Actin	Acute viral hepatitis, chronic HCV, NAFLD
LKM-1 (−4%)	CYP 2D6	Chronic HCV
pANCA (−90%)	Lactoferrin, other unknown antigens	PSC, PBC
SLA/LP (10% to 30%)	UGA repressor tRNA-associated protein	Hepatitis C
LC-1 (<5%)	Formiminotransferase cyclodeaminase	Chronic HCV
ASGP-R (−90%)	Asialoglycoprotein receptor	Chronic HBV, HCV, ALD, PBC

Diagnostic Criteria

Definite AIH	Probable AIH
Normal alpha-1 AT phenotype	Partial alpha-1 AT deficiency
Normal ceruloplasmin level	Nondiagnostic ceruloplasmin/copper levels
Normal iron and ferritin levels	Nondiagnostic iron and/or ferritin changes
No active hepatitis A, B, and/or C infection	No active hepatitis A, B, and/or C infection
Daily alcohol < 25 g/day	Daily alcohol < 50 g/day
No recent hepatotoxic drugs	No recent hepatotoxic drugs
Predominant serum AST/ALT abnormality	Predominant serum AST/ALT abnormality
Globulin, gamma-globulin or IgG level ≥ 1.5 times upper limit of normal ANA, SMA, or anti-LKM1 ≥ 1:80 in adults, ≥ 1:20 in children; no AMA	Hypergammaglobulinemia of any degree ANA, SMA or anti-LKM1 ≥ 1:40 in adults; other autoantibodies
Interface hepatitis, moderate to severe No biliary lesions, granulomas, or prominent changes suggestive of another disease	Interface hepatitis, moderate to severe. No biliary lesions, granulomas, or prominent changes suggestive of another disease
AIH = autoimmune hepatitis; alpha-1 AT = alpha-1 antitrypsin; ANA = antinuclear antibodies; SMA = smooth muscle antibodies; anti-LKM1 = antibodies to liver/kidney microsome type 1; AMA = antimitochondrial antibodies; IgG = serum immunoglobulin G level; AST = aspartate aminotransferase; ALT = alanine aminotransferase

Treatment and Prognosis

Remission in 55% of patients after 2 years of therapy. Ten year life expectancy in 90% with or without cirrhosis.
Relapse occurs in 50% of patients 6 months after drug withdrawal. Re-treatment induces remission.
Failure occurs in 9% of patients.
Maximum possible response consists of some but no complete response in 3 years of therapy.

Reference

Autoimmune Hepatitis
		Uploaded: 2007-11-25, Updated: 2007-11-25