Freelance Writing Jobs | Today's Articles | Sign In

Autoimmune Hepatitis I

Apr 4, 2006 Elaine Moore

In Part I of this two-part article on autoimmune hepatitis, I present an overview of the symptoms, environmental triggers, prevalence and nature of autoimmune hepatitis and I describe the autoantibodies that are seen in this condition.

Hepatitis is a liver disease characterized by either inflammation or destruction of liver cells. The most common cause of hepatitis is infection with one of the hepatitis viruses. Other causes include drug overdoses, alcohol abuse, bacterial infection, exposure to plant and chemical toxins, an idiosyncratic reaction to certain drugs, and an autoimmune condition known as autoimmune hepatitis (AIH).

The symptoms of hepatitis are the same regardless of the specific type or cause of liver inflammation. Overall, symptoms and signs of hepatitis include fatigue, enlarged liver, enlarged spleen, jaundice, which is a yellowing of the skin and eyes, low platelet count, fever, malaise, joint pain, nausea and vomiting. In addition, patients with AIH may have acne, puffy facial features, hirsutism (increased facial hair), obesity, pigmented abdominal striae or stretch marks, and absent or decreased menstrual periods. Blood levels of liver enzymes are typically elevated, and in patients with jaundice bilirubin levels are also elevated. Before bilirubin levels become elevated in the blood, bile may be detected in the urine. A positive bile result in a urinalysis assay is often the earliest sign of hepatitis.

The only way to differentiate one type of hepatitis from another is with laboratory tests. In AIH patients have increased blood levels of gamma globulin and one or more autoantibodies that target the liver. Women represent about 80 percent of all cases of AIH and two major age groups are affected: young people between ages 10 and 20 years; and people older than 55 years. Up to 17 percent of patients with AIH have a second autoimmune disorder, predominantly autoimmune thyroid disease, including both Hashimoto's thyroiditis and Graves' disease. Other autoimmune conditions that coexist with AIH include pernicious anemia, autoimmune hemolytic anemia, rheumatoid arthritis, Sjogren's syndrome, ulcerative colitis, myasthenia gravis, glomerulonephritis, celiac disease, vitiligo, and type I diabetes.

AIH has three distinct subtypes, types I, II, and III, which are described further in the Part II of this article. About 10 percent of patients with AIH, especially patients with subtype I, usually have mild symptoms that wax and wane and spontaneously resolve. Most patients, however, develop a chronic form of AIH that persists, and without treatment, can progress to cirrhosis.

AIH is found worldwide. In the United States, at any given time, approximately 100,000-200,00 cases typically occur with AIH accounting for about 11-23 percent of all cases of chronic liver disease. AIH is known to occur after infection with hepatitis A, B and C. Occasionally, a prolonged or relapsing condition of hepatitis A may be confused with autoimmune hepatitis. Other environmental triggers of AIH include: the Epstein-Barr virus (EBV) and the measles virus; Salmonella and Escherichia coli bacteria; the medications halothane, interferon, minocycline, melatonin, alpha methyldopa, oxyphenistatin, and nitrofurantoin; and the herbs black cohosh and Dai-saiko-lo. Interferon therapy used for hepatitis C has occasionally been found to induce latent autoimmune hepatitis.

Autoantibodies seen in AIH include: antinuclear antibody (ANA) with a homogenous pattern primarily seen in subtype I; antibodies to double-stranded DNA (anti-dsDNA); anti-smooth muscle antibody (anti-SMA) primarily seen in type I; anti-liver-kidney microsomal antibody (anti-LKM-1) primarily seen in type II; anti-soluble liver antigen (anti-SKA) primarily seen in type III. Some patients with AIH may also have rheumatoid factor and antiphospholipid antibodies.

Resource: Hepatitis, A Practical Guide, by Elaine A. Moore, Fall, 2006, Jefferson, NC: McFarland Publishing.

The copyright of the article Autoimmune Hepatitis I in General Medicine is owned by Elaine Moore. Permission to republish Autoimmune Hepatitis I in print or online must be granted by the author in writing.