Autoimmune hepatitis is a rare type of chronic hepatitis, currently classified as "type 1" or "type 2". It may eventually lead to cirrhosis. The role of imaging is primarily to exclude other diagnoses and evaluate for complications.
It may occur in children or adults, but most patients are affected at 40-60 years old. The incidence in Western Europe is ~0.01-0.02% 2.
There is no predilection for an ethnic group. There is a female predominance: 3.6: 1.
It has a variable clinical presentation. Patients may be asymptomatic or present in acute liver failure (rare), or anywhere between. Tends to have a relapsing-remitting course. There is an association with other autoimmune conditions.
Depending on the phase, the patient may present with
- hepatomegaly +/- splenomegaly
- elevated aminotransferases (ALT and AST)
Autoimmune hepatitis may encompass multiple different conditions.
- "classic" autoimmune hepatitis
- ANA, IgG4, and anti-smooth muscle antibody may be elevated, with the last (1:320) a relatively more specific finding in type 1
- ANCA is more often found in type 1 than in type 2
- has antibodies to liver/kidney microsomes (ALKM-1) or to a liver cytosol antigen (ALC-1)
Biopsy and histopathology is less specific for a diagnosis, compared to serum markers.
The role of imaging in a patient with possible autoimmune hepatitis is threefold:
- to exclude other possibilities of chronic hepatitis
- to look for complications of cirrhosis (such as HCC)
- to look for autoimmune involvement of other organs (such as the pancreas).
Nonspecific, ranging from normal to hepatomegaly and cirrhosis.
- T2: nonspecific, increased periportal oedema 4
- MRCP: primary sclerosing cholangitis (PSC) should be excluded
Treatment and prognosis
Treatment is similar to other autoimmune conditions, and often uses immunomodulating medications.
- 1. Manns MP, Czaja AJ, Gorham JD et-al. Diagnosis and management of autoimmune hepatitis. Hepatology. 2010;51 (6): 2193-213. doi:10.1002/hep.23584 - Pubmed citation
- 2. Ngu JH, Bechly K, Chapman BA et-al. Population-based epidemiology study of autoimmune hepatitis: a disease of older women?. J. Gastroenterol. Hepatol. 2010;25 (10): 1681-6. doi:10.1111/j.1440-1746.2010.06384.x - Pubmed citation
- 3. Krawitt EL. Autoimmune hepatitis. N. Engl. J. Med. 2006;354 (1): 54-66. doi:10.1056/NEJMra050408 - Pubmed citation
- 4. Kawamoto S, Soyer PA, Fishman EK et-al. Nonneoplastic liver disease: evaluation with CT and MR imaging. Radiographics. 1998;18 (4): 827-48. doi:10.1148/radiographics.18.4.9672968 - Pubmed citation