LKM-1 Antibody (IgG)

Liver Kidney Microsomal (LKM-1) Antibody (IgG)

The presence of LKM-1 antibodies can be used in conjunction with clinical findings and other laboratory tests to aid in the diagnosis of autoimmune liver diseases such as autoimmune hepatitis (AIH-2).

What is autoimmune hepatitis?

AIH is a chronic disorder characterized by progressive hepatocellular loss and cell-mediated immunologic attack. Histologic inflammation is present and is usually accompanied by fibrosis, which can progress to cirrhosis and liver failure. AIH accounts for 11% to 23% of chronic liver disease in North America and about 4% to 6% of adult liver transplants in the United States and Europe.

Early diagnosis and initiation of immunosuppressive therapy are essential to prevent severe liver damage.

Although patients may present with acute symptoms (eg, "arthralgia" = joint pain), about 34% to 45% are asymptomatic and are identified subsequent to abnormal liver function tests such as increased alanine and/or aspartate aminotransferase (generally <500 U/L but occasionally 500 U/L to 1000 U/L).

Elevated levels of globulin, gamma globulin, or immunoglobulin G (≥1.5 times the upper limit of the reference ranges) are typically present. Because the clinical features of AIH overlap with other forms of hepatitis, ruling out hereditary, infectious, and toxicity-related causes of liver disease is an important component of diagnosis. Interface hepatitis (piecemeal necrosis) in liver biopsy tissue is considered essential for diagnosis; portal plasma cell infiltration is typically present but not specific for AIH.