Causes of Autoimmune Hepatitis
As the name implies, autoimmune hepatitis is an autoimmune disease. This means that for some reason the immune system mistakes a person's own cells as invaders and attacks them, causing damage. Similar to other autoimmune diseases, scientists still do not know the cause or causes of autoimmune hepatitis and why the immune system turns against itself. However, research over the last few years has begun to piece together the factors involved. Based on recent research, it is believed that the main causes of autoimmune hepatitis may be linked to a combination of:
 
Genetic factors
Environmental factors.
 
Genetic (Inherited) Factors
Many people with autoimmune hepatitis have a first-degree relative with the disease or with other autoimmune diseases. Also, about 70 percent of those with autoimmune hepatitis are women; most are between the ages of 15 and 40. This suggests that genetics plays a role in the cause of autoimmune hepatitis.
 
Autoimmune hepatitis research scientists have also discovered that certain genes known to play a role in the immune system are associated with a tendency to develop autoimmune hepatitis. Some people with autoimmune hepatitis do not have these particular genes; and still others have these genes but never develop the disease. These somewhat contradictory data suggest that a person's genetic makeup plays an important role in determining if he or she will develop autoimmune hepatitis, but that it is not the only factor.
 
Environmental Factors
As with other autoimmune diseases, many scientists think that something must occur to trigger the disease process in people whose genetic makeup makes them susceptible to autoimmune hepatitis. At this point, they think it could be certain bacteria, viruses, toxins, or drugs; but the exact cause is not yet known. Keep in mind that this does not mean that autoimmune hepatitis is contagious; a person cannot catch the disease from someone else.