At a Glance
Why Get Tested?
To help diagnose autoimmune hepatitis and distinguish it from other causes of liver injury
When to Get Tested?
A blood sample drawn from a vein in your arm
Test Preparation Needed?
The Test Sample
What is being tested?
Liver kidney microsome type 1 (anti-LKM-1) antibodies are autoantibodies, proteins produced by the body's immune system that recognize and target its own enzyme called cytochrome P450 2D6 (CYP2D6), a protein found primarily in liver cells. The development of anti-LKM-1 antibodies is strongly associated with type 2 autoimmune hepatitis. This test detects and measures the amount (titer) of anti-LKM-1 (or antibody against CYP2D6) in the blood.
Autoimmune hepatitis is an acute or chronic inflammation of the liver that can lead to liver cirrhosis and, in some cases, to liver failure. It is hepatitis that is not due to another identifiable cause, such as a viral infection, exposure to a drug or toxin, a hereditary disorder, or alcohol abuse. Anyone can develop the disorder, but the majority of those affected are women.
There are two main types of autoimmune hepatitis. Type 1 is the most common form of autoimmune hepatitis in the United States and is associated with the presence of smooth muscle antibodies (SMA) in the blood. Type 2 is less common and tends to be more severe. It is associated with anti-LKM-1 antibodies and primarily affects young girls and is more common in Europe than in the United States.
How is the sample collected for testing?
A blood sample is obtained by inserting a needle into a vein in the arm.
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
Is any test preparation needed to ensure the quality of the sample?
No test preparation is needed.
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NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.
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