Typically affects young women; in the mild form the disease is often symptomless and is diagnosed by incidentally detected increase in the serum liver aminotransferase concentrations.
If the treatment is started in time, the progression of hepatitis to liver cirrhosis can be influenced.
In severe disease, liver transplantation may be required.
Epidemiology
Incidence is approximately 2/100 000 inhabitants, prevalence approximately 17/100 000 inhabitants.
70-80% of all patients with chronic autoimmune hepatitis are women. Half of the patients become affected before their 30th birthday.
Symptoms and signs
Mild forms are often asymptomatic and the increase in liver aminotransferases is detected incidentally.
Fatigue, loss of appetite, weight loss, aversion for fatty foods and alcohol
The most common initial finding is increase in liver aminotransferase concentrations.
30-40% of the patients have acute hepatitis at presentation.
Jaundice is observed in 30%.
Women have amenorrhoea, men have gynaecomastia.
Hepato- and splenomegaly
Spider naevi
Up to 40% of the patients have concurrently other autoimmune diseases.
Chronic diarrhoea, skin lesions, joint symptoms, chronic thyroiditis, haemolytic anaemia, thrombocytopenia, ulcerative colitis, pleuritis, or pericarditis are sometimes associated with the disease.
In advanced disease, the findings are related to liver cirrhosis, portal hypertension and liver failure.
Plasma aminotransferase concentrations, particularly ALT, are markedly increased (often 10 times above reference values).
Plasma alkaline phosphatase (ALP) and serum bilirubin are increased to a lesser extent.
Serum IgG is elevated most in hypergammaglobulinaemia.
Antibodies against smooth muscle are detected in 40-60% of the patients
Antinuclear antibodies are detected in 50-80% of the patients.
Serology for viral hepatitis is negative.
Mild forms of the disease
ALT concentration is slightly or moderately increased.
Plasma ALP, albumin and serum gammaglobulin concentrations are usually normal, serum IgG is slightly increased.
Diagnosis
The above mentioned laboratory findings in a young woman suggest autoimmune hepatitis.
The diagnosis may be confirmed by liver biopsy. It is, however, not always diagnostic, but liver biopsy is the only method for assessing the activity of the disease and the stage of fibrosis.
Liver biopsy may be repeated after 1-2 years if there is uncertainty about the diagnosis or the efficacy of treatment.
Treatment and prognosis
The initial therapy consists of prednisolone30-60 mg daily until the aminotransferase concentrations have become normal or close to normal. Thereafter, the glucocorticoid is tapered down slowly.
Azathioprine or mercaptopurine is added to the glucocorticoid either in the initial stage or once the liver values have decreased. The maintenance dose of azathioprine is 1-2 mg/kg daily.
Often the combination therapy with prednisolone 5-15 mg daily + azathioprine 1-2 mg/kg daily is continued for months, for up to 2-3 years, but the aim is to discontinue the glucocorticoid and to continue with only azathioprine 1-2 mg/kg daily as maintenance therapy.
Budesonide is sometimes used instead of prednisolone in the initial therapy (starting from 9 mg daily) or in maintenance therapy, especially if there are contraindications to prednisolone, e.g. diabetes or osteoporosis.
Discontinuing the medication may be tried if the liver tests and immunoglobulin levels have been normal for over a year. Before the medication is stopped, liver biopsy is used to guarantee that the disease activity has ceased.
Relapses are common.
80-90% of the treated patients are alive after 10 years compared with the 5-year survival rate of 50% in patients without treatment.
Liver transplantation may be considered in patients with cirrhosis-associated liver failure or some other complication.