Autoimmune hepatitis is liver inflammation that occurs when your body’s immune system turns against liver cells. The exact cause of autoimmune hepatitis is unclear, but genetic and environmental factors appear to interact over time in triggering the disease. Hepatitis which generally involves young women who are well nourished with moon facies, acne, amenorrhea hirsuties, pigmentation and abdominal striae when untreated autoimmune hepatitis can lead to scarring of the liver (cirrhosis) and eventually to liver failure. When diagnosed and treated early, however, autoimmune hepatitis often can be controlled with drugs that suppress the immune system..
Onset is insidious and patient may be asymptomatic for number of years. Patient is mildly jaundiced with hepatosplenomegaly. Signs of chronic liver disease in the form of cirrhosis may appear.
Since Autoimmune hepatitis is autoimmune disease, episodes of fever with polyarthritis of rheumatid type appear. The cause of the disease is not known but a complex interaction between triggering factors, auto antigen, genetic predisposition and immune regulatory networks is operative.
Because of deranged immuno regulation auto antibodies against hepatocytes, surface antigens are produced. A genetic predisposition is an absolute prerequisite. Predisposition only is inherited and not the disease which must be triggered by an antigen.
Humoral disturbances are present characterized mainly of IgG and rise in anti nuclear antibodies (ANA) and anti-smooth muscle antibodies. Suppressor T cell function is impaired and it plays important role in the pathogenesis of the disease.
Other auto immune diseases may co-exist. Hepatitis C virus infection has also been incriminated in the pathogenesis of disease. The disease has been divided into three types: Type I is present in elderly women; Type II, the most common, is seen in young women; and type III is present in children.
Diagnosis of the diseases is made by clinical picture of chronic liver disease, presence of hypergammaglobulinaemia, auto antibodies (ANA, ASMA) and absent HBs Ag. Enzyme levels (AST/ ALT) are elevated.
Types of Autoimmune Hepatitis
Autoimmune hepatitis occurs when the body’s immune system, which ordinarily attacks viruses, bacteria and other pathogens, instead targets the liver. This attack on your liver can lead to chronic inflammation and serious damage to liver cells. Just why the body turns against itself is unclear, but researchers think autoimmune hepatitis could be caused by the interaction of genes controlling immune-system function and exposure to particular viruses or drugs.
Types of autoimmune hepatitis
Doctors have identified two main forms of autoimmune hepatitis:
Type 1 autoimmune hepatitis. This is the most common type of the disease. It can occur at any age. About half the people with type 1 autoimmune hepatitis have other autoimmune disorders, such as celiac disease, rheumatoid arthritis or ulcerative colitis.
Type 2 autoimmune hepatitis. Although adults can develop type 2 autoimmune hepatitis, it’s most common in children and young people. Other autoimmune diseases may also accompany this type of autoimmune hepatitis.
Treatment for Autoimmune hepatitis
Prednisolone is the drug of choice and is given in the dose of 1-1.5 mg/kg body weight /day in divided doses. This produces improvement in the form of decrease in jaundice, fall in serum globulins, auto antibodies levels and decrease in size of spleen. Patient soon gets a feeling of well being.
Treatment of Autoimmune hepatitis has to be continued for a long period spread over months to years. Prednisolone needs to be tapered off slowly and the patient may even require a maintenance dose.
Azathioprine in the dose of 50-100 mg/day is used along with prednisolone. Its main benefit is to act as a steroid sparing drug whose dosage can be reduced.