What causes AIH?
While the cause is not clearly defined, field experts hypothesize that there are both genetic and an environmental elements underlying autoimmune hepatitis. There are over 80 known autoimmune diseases, each occurring when the immune system begins attacking some part of the body. The immune system is a very complex system of checks and balances, normally functioning to help protect our body from many types of infections. When the balance is disrupted, cells within this system can attack and injure healthy cells in the same body. The genetic susceptibility to autoimmune conditions is not from just one abnormal gene, but likely a combination of genetic alterations establishing the perfect environment for autoimmune conditions to occur. These genetic traits can be inherited, thus it is common to see autoimmune diseases in families. In autoimmune hepatitis, genetic risk factors in combination with an environmental trigger, such as extreme stress, some viruses, or various medications or chemical exposures occurs to trigger the immune system the body's white blood cells begin to attack the liver, causing inflammation and tissue damage. This uncontrolled inflammation is referred to as hepatitis, a general term which means "inflammation of the liver." Prolonged or severe inflammation can result in fibrosis or cirrhosis – scar tissue in the liver. Known environmental triggers of autoimmune hepatitis include medications such as statins, minocycline, and nitrofurantoin; and viruses including Epstein Barr, cytomegalovirus, and measles. Unfortunately, researchers believe we still only know some of the risk factors for autoimmune hepatitis.