ImmunologyGastroenterology

Liver-Kidney Microsome (LKM)-1 Antibody (ELISA)

Normal Range
< 20.0 U/mL (Negative)
Sample Type
Serum
Fasting
No
Unit
U/mL

Function

The Liver-Kidney Microsome Type 1 (LKM-1) antibody test is a specialized immunological assay used primarily to identify the presence of autoantibodies directed against the enzyme cytochrome P450 2D6. In a healthy immune system, antibodies protect the body from external pathogens. However, in autoimmune conditions, the body loses self-tolerance and begins attacking its own cellular components. The LKM-1 antibody specifically targets proteins within the hepatocytes (liver cells) and renal proximal tubular cells (kidney cells).

Why it is Ordered

This test is crucial when a physician suspects Autoimmune Hepatitis (AIH), specifically Type 2. AIH is a chronic condition where the immune system attacks the liver, leading to inflammation and potential scarring (cirrhosis). While Type 1 AIH is more common in adults and associated with ANA (Antinuclear Antibodies), Type 2 AIH is more frequently seen in children and adolescents. Doctors order this test when a patient presents with unexplained jaundice, fatigue, abdominal pain, or elevated liver enzymes (ALT/AST) that do not respond to standard viral hepatitis treatments.

Associated Conditions

  • Autoimmune Hepatitis Type 2: This is the primary condition associated with LKM-1. It is often more aggressive than Type 1 and requires long-term immunosuppression.
  • Chronic Hepatitis C: A subset of patients with Hepatitis C virus (HCV) may develop LKM-1 antibodies, though usually at lower titers than those seen in AIH.
  • Drug-Induced Liver Injury: Certain medications can trigger an immune response that mimics the appearance of LKM-1 antibodies.
  • AIRE Deficiency: Part of the Autoimmune Polyendocrinopathy-Candidiasis-Ectodermal Dystrophy (APECED) syndrome.

Check Your Result

Check Your Result

Interactive
U/mL

Enter your lab result to see where you stand compared to the standard reference range.

Why Context Matters

A second opinion is often vital because LKM-1 antibodies can sometimes be transiently present in patients with Hepatitis C or drug-induced liver toxicity, leading to a potential misdiagnosis of lifelong autoimmune hepatitis. Furthermore, the ELISA method can occasionally yield low-level false positives. It is essential to correlate these results with a liver biopsy and other markers like ASMA or ANA to ensure a correct diagnosis before commencing high-dose steroid therapy.

Lab ranges are statistical averages, not biological laws. "Normal" for a 20-year-old male isn't normal for a 60-year-old female.

Clinical References

Source-of-truth databases and clinical guidelines for Liver-Kidney Microsome (LKM)-1 Antibody (ELISA):

Related Indicators

DR

Medically Reviewed by Dr. Binoy Babu, MBBS

Board Certified Doctor • 10+ Years Clinical Experience

Dr. Babu is a practicing physician dedicated to empowering patients with clear, actionable medical information. He founded 2opi to bridge the gap between complex lab reports and patient understanding, ensuring everyone has access to a reliable second opinion.

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