Test ID: LKM
Liver/Kidney Microsome Type 1 Antibodies, Serum
Secondary ID
A test code used for billing and in test definitions created prior to November 2011
NY State Approved
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Useful For
Suggests clinical disorders or settings where the test may be helpful
Evaluation of patients with liver disease of unknown etiology
Evaluation of patients with suspected autoimmune hepatitis
Method Name
A short description of the method used to perform the test
Enzyme-Linked Immunosorbent Assay (ELISA)
Reporting Name
A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Aliases
Lists additional common names for a test, as an aid in searching
Antibodies to Liver\Kidney Microsome Type 1, Serum
LKM1 (liver/kidney microsome type 1) antibodies
Microsomal (Liver/Kidney) Type 1 Antibodies
Specimen Type
Describes the specimen type needed for testing
Specimen Required
Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Specimen Volume: 0.5 mL
Specimen Minimum Volume
Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Hemolysis | Mild OK; Gross reject |
| Lipemia | Mild OK; Gross reject |
| Icterus | Mild OK; Gross OK |
| Other | NA |
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
| Specimen Type | Temperature | Time |
|---|---|---|
| Serum | Refrigerated (preferred) | 21 days |
| Frozen | 21 days |
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Autoimmune liver disease (eg, autoimmune hepatitis and primary biliary cirrhosis) is characterized by the presence of autoantibodies including smooth muscle antibodies (SMA), antimitochondrial antibodies (AMA), and anti-liver/kidney microsomal antibodies type 1 (anti-LKM-1).(1) Subtypes of autoimmune hepatitis (AIH) are based on autoantibody reactivity patterns.
Anti-LKM-1 antibodies serve as a serologic marker for AIH type 2 and typically occur in the absence of SMA and antinuclear antibodies. These antibodies react with a short linear sequence of the recombinant antigen cytochrome monooxygenase P450 2D6.(2) Patients with AIH type 2 more often tend to be young, female, and have severe disease that responds well to immunosuppressive therapy.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
< or =20.0 Units (negative)
20.1-24.9 Units (equivocal)
> or =25.0 Units (positive)
Reference values apply to all ages.
Interpretation
Provides information to assist in interpretation of the test results
Seropositivity for anti-LKM-1 antibodies is consistent with a diagnosis of AIH type 2.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Serologic tests for autoantibodies, including anti-LKM-1, should not be relied upon exclusively to determine the etiology or prognosis of patients with liver disease.
Anti-LKM-1 antibodies may occur in some patients with chronic hepatitis caused by hepatitis C virus infection. Although the epitopes recognized by anti-LKM-1 antibodies in hepatitis C virus infection are different than in patients with AIH type 2, physicians must use caution in interpreting the results of tests for anti-LKM-1 antibodies in such patients.
Clinical Reference
Provides recommendations for further in-depth reading of a clinical nature
1. Clinical Immunology Principles and Practice. Third edition. Edited by RR Rich, TA Fliesher, WT Shearer, et al: Philadelphia, PA, Mosby Elsevier, 2008
2. Czaja AJ, Homburger HA: Autoantibodies in liver disease. Gastroenterology. January 2001;120(1):239-249
Method Description
Describes how the test is performed and provides a method-specific reference
Enzyme-linked immunosorbent assay (ELISA) for the semi-quantitative detection of LKM-1 antibodies in human serum. (Package insert: INOVA Diagnostics, Inc. San Diego, Revision 1, March 2000)
Day(s) and Time(s) Test Performed
Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday, Wednesday, Friday
Analytic Time
Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time
Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
The location of the laboratory that performs the test
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
86376
LOINC® Code Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
| Result ID | Reporting Name | LOINC Code |
|---|---|---|
| LKM | Liver/Kidney Microsome Type 1 Ab, S | 32220-6 |


