Autoimmune hepatitis

Autoimmune hepatitis
Micrograph showing a lymphoplasmacytic interface hepatitis—the characteristic histomorphologic finding of autoimmune hepatitis. Liver biopsy. H&E stain.
Specialty	Gastroenterology, hepatology
Symptoms	Often asymptomatic, fatigue, right upper abdominal pain, anorexia, nausea, jaundice, joint pain, rash
Complications	Chronic liver disease, cirrhosis
Usual onset	Bimodal presentation: 10-20 years of age, 40-50 years of age
Duration	Lifelong
Types	Type 1, type 2, seronegative
Causes	Genetic predisposition with environmental trigger
Risk factors	Female gender, additional autoimmune disease
Diagnostic method	Liver enzyme levels, antibody panels. Definitive: Liver biopsy
Differential diagnosis	Primary biliary cholangitis Primary sclerosing cholangitis
Treatment	Prednisone, Azathioprine
Prognosis	<50% survival if untreated, >90% survival if treated
Frequency	Incidence 1-2 per 100,000 per year Prevalence 10-25 per 100,000

Autoimmune hepatitis, formerly known as lupoid hepatitis, plasma cell hepatitis, or autoimmune chronic active hepatitis, is a chronic, autoimmune disease of the liver that occurs when the body's immune system attacks liver cells, causing the liver to be inflamed. Common initial symptoms may include fatigue, nausea, muscle aches, or weight loss or signs of acute liver inflammation including fever, jaundice, and right upper quadrant abdominal pain. Individuals with autoimmune hepatitis often have no initial symptoms and the disease may be detected by abnormal liver function tests and increased protein levels during routine bloodwork or the observation of an abnormal-looking liver during abdominal surgery.^[1]

Anomalous presentation of MHC class II receptors on the surface of liver cells,^[2] possibly due to genetic predisposition or acute liver infection, causes a cell-mediated immune response against the body's own liver, resulting in autoimmune hepatitis. This abnormal immune response results in inflammation of the liver, which can lead to further symptoms and complications such as fatigue and cirrhosis.^[3] The disease is most often diagnosed in patients in their late teens or early 20s and between the ages of 40 and 50. It affects women more commonly than men.^[4]