Autoimmune hepatitis
Also known as lupus hepatitis, plasma cell hepatitis, or autoimmune chronic active hepatitis in past years, autoimmune hepatitis is a chronic autoimmune disease of the liver that causes inflammation of the liver when the body’s immune system attacks liver cells. Initial symptoms are usually not obvious, and abnormal liver function can be observed by liver function tests and routine blood tests, or abnormalities in the liver can be detected during abdominal surgery. It is believed that the abnormal presentation of MHC class II receptors on the surface of hepatocytes may be related to genetic susceptibility or acute liver infection, resulting in cell-mediated autoimmune hepatitis. In addition, environmental predisposing factors (viruses, drugs, herbs, immunizations) and immune dysfunction can lead to chronic inflammation of hepatocyte and subsequent fibrosis. Findings associated with chronic hepatitis are present in 60% of patients, but serological evidence of viral infection is lacking. Patients are mostly diagnosed between the ages of 40 and 50 years, and the disease is more common in women than in men. European studies show that 1-2 per 100,000 people are affected, but in some cases up to 10-25 per 100,000 people are affected.
Signs and symptoms
Some patients may be completely asymptomatic (12-35% of cases) with signs of chronic liver disease or acute or even fulminant liver failure. Most patients present with fatigue, lethargy, weight loss, mild right upper quadrant pain, malaise, anorexia, pruritus, nausea, jaundice, or arthralgias. Rarely, a rash or unexplained fever may occur. In women, amenorrhea is common. Physical examination results may be normal, but symptoms of chronic liver disease may also be present. Many initially present only with laboratory abnormalities, unexplained increases in aminotransferases, and some patients have developed cirrhosis at the time of diagnosis. Autoimmune hepatitis may overlap with other autoimmune diseases such as type 1 diabetes, ulcerative colitis, unifying lupus erythematosus, celiac disease, vasculitis, and autoimmune thyroiditis.
Diagnosis
After excluding other causes (e. g, viral, genetic, metabolic, cholestatic, and drug-induced liver disease), the diagnosis can be effectively made in combination with clinical, laboratory, and histologic findings.
Treatment
- In symptomatic individuals with evidence of interface hepatitis and necrosis on liver biopsy, the mainstay of treatment is immunosuppressive glucocorticoids during an acute attack, with resolution of symptoms achieved in approximately 60 to 80% of cases, but many cases eventually relapse. For patients with moderate to severe disease who cannot tolerate glucocorticoids, low-dose prednisone monotherapy or combination therapy with azathioprine is a reasonable alternative.
- Patients with autoimmune hepatitis who do not respond to glucocorticoids and azathioprine may be given other immunosuppressants such as mycophenolate mofetil, cyclosporine, tacrolimus, or methotrexate.
- About 7% to 40% of treated patients develop cirrhosis. Liver transplantation is the standard of care for patients with fulminant liver failure or in patients whose disease progression cannot be controlled by multiple treatments.