The Liver-Kidney Microsome-1 Ab (LKM 1) test is a blood test used to detect the presence of autoantibodies that attack the liver and kidney cells. These antibodies are specifically directed against the liver-kidney microsomal antigens, which are found in the liver and kidney cells. The presence of LKM 1 antibodies is a hallmark of autoimmune hepatitis, a condition where the immune system mistakenly attacks the liver cells, leading to inflammation and damage. The LKM 1 test is usually done in conjunction with other tests, such as the liver function test and other autoimmune marker tests, to diagnose autoimmune hepatitis. However, the LKM 1 test has some limitations, as it is not specific for autoimmune hepatitis and can be positive in other conditions, such as viral hepatitis or drug-induced liver injury. Therefore, clinical correlation and further testing may be required for accurate diagnosis and management.