Autoimmune hepatitis (AIH) is a rare disease, characterized by female predominance, hypergammaglobulinemia, autoantibodies, association with HLA DR3 and HLA DR4 and a good response to immunosuppression.

 AIH type 1 is characterized by anti-nuclear (ANA) and/or anti-smooth muscular (SMA) autoantibodies.
 AIH type 2 is characterized by liver/kidney microsomal autoantibodies (LKM).
 AIH type 3 may be distinguished by autoantibodies to soluble liver proteins (SLA) or the liver pancreas antigen (LP).

AIH-2 affects predominantly pediatric patients and is characterized by a more severe clinical course, a higher frequency of relapse under immunosuppressive treatment and a more frequent progression to cirrhosis. AIH types 1 and 3 show a higher age of onset and a better long-term response to immunosuppressive treatment.

Synopsis

 hypergammaglobulinemia
 multifocal hepatic necrosis with bridging in the acute stage
 aggressive hepatitis with mononuclear cell infiltration or macronodular cirrhosis in the late stages

Lesional patterns

 autoimmune active chronic hepatitis
 autoimmune panlobular hepatitis
 autoimmune bridging mecrosis
 autoimmune massive hepatic necrosis

Types

 type 1 autoimmune hepatitis (lupoid hepatitis) (anti-smooth muscle antibody, antinuclear antibodies)
 type 2 autoimmune hepatitis (LKM1-associated autoimmune hepatitis or anti-LKM1 chronic active hepatitis)
 type 3 autoimmune hepatitis (soluble liver antigen, liver/pancreas antigen)

Associations

 autoimmune disease

• celiac disease
• primary sclerosing cholangitis
• inflammatory bowel diseases (IBDs) (#9123955#, #8447289#)
• familial autoimmune enteropathy (#7996356#)
• cryoglobulinaemia
• primary biliary cirrhosis (#16416210#)
• autoimmune enteric leiomyositis (#15948126#)

 miscellaneous

• erythroblastopenia
• cancer (#10755264#)
• trisomy 21 (#10777202#)

Overlaps

 primary biliary cirrhosis (PBC)
 primary sclerosing cholangitis
 chronic hepatitis C-immune predominant
 chronic hepatitis C-immune predominant
 autoimmune cholangitis
 cryptogenic chronic hepatitis

References

 Krawitt EL. Autoimmune hepatitis. N Engl J Med. 2006 Jan 5;354(1):54-66. PMID: #16394302#

 Brunt EM, Di Bisceglie AM. Histological changes after the use of mycophenolate mofetil in autoimmune hepatitis. Hum Pathol. 2004 Apr;35(4):509-12. PMID: #15116334#

 Misdraji J, Thiim M, Graeme-Cook FM. Autoimmune hepatitis with centrilobular necrosis. Am J Surg Pathol. 2004 Apr;28(4):471-8. PMID: #15087666#

 Obermayer-Straub P, Strassburg CP, Manns MP. Autoimmune hepatitis. J Hepatol. 2000;32(1 Suppl):181-97. PMID: #10728804#

 Alvarez F, Berg PA, Bianchi FB, Bianchi L, Burroughs AK, Cancado EL, Chapman RW, Cooksley WG, Czaja AJ, Desmet VJ, Donaldson PT, Eddleston AL, Fainboim L, Heathcote J, Homberg JC, Hoofnagle JH, Kakumu S, Krawitt EL, Mackay IR, MacSween RN, Maddrey WC, Manns MP, McFarlane IG, Meyer zum Buschenfelde KH, Zeniya M, et al. International Autoimmune Hepatitis Group Report: review of criteria for diagnosis of autoimmune hepatitis. J Hepatol. 1999 Nov;31(5):929-38. PMID: #10580593#

 Burgart LJ, Batts KP, Ludwig J, Nikias GA, Czaja AJ. Recent-onset autoimmune hepatitis. Biopsy findings and clinical correlations. Am J Surg Pathol. 1995 Jun;19(6):699-708. PMID: #7755156#

 Homberg JC, Abuaf N, Bernard O, Islam S, Alvarez F, Khalil SH, Poupon R, Darnis F, Levy VG, Grippon P, et al. Chronic active hepatitis associated with antiliver/kidney microsome antibody type 1: a second type of "autoimmune" hepatitis. Hepatology. 1987 Nov-Dec;7(6):1333-9. PMID: #3679093#