Elevated ALT indicates liver damage, which can be caused by a variety of reasons: 1, viral infections: need to test the appropriate markers, such as hepatitis A / B / C / E, CMV / EBV, etc. 2.Alcohol: heavy alcohol consumption. 3.Fatty liver: caused by fatty deposits. 4.Drugs: Taken drugs/foods/health products that hurt the liver, etc. 5.Autoimmune disorder: often accompanied by other discomfort. 6.Liver manifestations of other systemic diseases.