What is the Liver Kidney Microsomal Antibodies test?

The Liver Kidney Microsomal (LKM) Antibodies test is a blood test that detects autoantibodies directed against enzymes found in liver and kidney cells, particularly cytochrome P450 enzymes.

LKM antibodies are most commonly associated with autoimmune hepatitis type 2 (AIH-2), a condition in which the immune system mistakenly attacks liver tissue, leading to inflammation and potential liver damage.

This test is used as part of a broader autoimmune liver disease work-up and is interpreted alongside liver enzymes, immunoglobulins, and other autoimmune markers.

Why do I need a Liver Kidney Microsomal Antibodies test?

Autoimmune liver disease can progress silently and may mimic other liver conditions. Identifying autoimmune markers allows early diagnosis and appropriate treatment.

You may need an LKM Antibodies test if you:

• Have persistently abnormal liver function tests
• Have suspected autoimmune hepatitis
• Have unexplained liver inflammation
• Are being assessed for chronic liver disease
• Have symptoms not explained by alcohol or viral hepatitis
• Have a personal or family history of autoimmune disease
• Need differentiation between liver disease causes

Symptoms associated with autoimmune liver disease may include:

• Fatigue
• Jaundice (yellowing of skin or eyes)
• Abdominal discomfort
• Nausea
• Joint pain
• Dark urine
• Itching

Benefits of the LKM Antibodies test

• Supports diagnosis of autoimmune hepatitis
  Particularly type 2 autoimmune hepatitis.
• Differentiates liver disease causes
  Helps distinguish autoimmune from viral or metabolic causes.
• Clinically established autoimmune marker
  Used in hepatology and immunology.
• Guides further diagnostic testing
  Indicates need for imaging or biopsy.
• Supports early intervention
  Enables timely immunosuppressive treatment.
• Useful in complex liver cases
  When standard causes are excluded.
• Complements other autoimmune tests
  Works alongside ANA, SMA and IgG.
• Simple blood test
  Requires only one blood sample.

Step by step – how the test works

You can access LKM Antibodies testing UK-wide through two options:

1. Clinic appointment
   Attend your nearest UK clinic where a healthcare professional will take your blood sample.
2. At-home or hotel visit (£60 extra)
   A qualified phlebotomist comes to your home or hotel, so you don’t need to travel.

Your sample is analysed in an accredited UK laboratory and results are delivered securely.

Your results explained

Negative LKM antibodies

No evidence of LKM-associated autoimmune liver disease.

Typical UK interpretation:

• LKM antibodies: Negative

Low-positive LKM antibodies

May suggest early or mild autoimmune activity; clinical correlation required.

Typical UK interpretation:

• Low-titre positive

High-positive LKM antibodies

Strongly suggest autoimmune hepatitis type 2.

Typical UK interpretation:

• High-titre positive

Results must be interpreted alongside liver enzymes, IgG levels and clinical findings.