Test Catalog

Test Id : SMAS

Smooth Muscle Antibody Screen, Serum

Useful For
Suggests clinical disorders or settings where the test may be helpful

Evaluating patients with chronic liver disease in whom the diagnosis of chronic active autoimmune hepatitis is suspected

Reflex Tests
Lists tests that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial tests.

Test Id Reporting Name Available Separately Always Performed
SMAT Smooth Muscle Ab Titer, S No No

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

If smooth muscle antibody (SMA) screen is positive then the SMA titer will be performed at an additional charge.

Method Name
A short description of the method used to perform the test

Indirect Immunofluorescence

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Smooth Muscle Ab Screen, S

Aliases
Lists additional common names for a test, as an aid in searching

Actin

F-actin

Immunology Profile

SMA (Smooth Muscle Antibodies)

SMA, Anti

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

If smooth muscle antibody (SMA) screen is positive then the SMA titer will be performed at an additional charge.

Specimen Type
Describes the specimen type validated for testing

Serum

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Container/Tube:

Preferred: Serum gel

Acceptable: Red top

Specimen Volume: 0.8 mL

Forms

If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:

-General Request (T239)

-Gastroenterology and Hepatology Client Test Request (T728)

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

0.4 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis Reject
Gross lipemia Reject
Gross icterus OK

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 14 days
Frozen 14 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Evaluating patients with chronic liver disease in whom the diagnosis of chronic active autoimmune hepatitis is suspected

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

If smooth muscle antibody (SMA) screen is positive then the SMA titer will be performed at an additional charge.

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Autoimmune hepatitis (AIH) is caused by chronic inflammation within the liver, resulting in damage to the hepatocytes.(1) Initially, patients with AIH may be clinically asymptomatic, usually identified only through an incidental finding of abnormal liver function tests. At a more advanced stage, patients may manifest with symptoms such as jaundice, pruritus, or ascites, which are secondary to the more extensive liver damage. As implied by the name, AIH has many characteristics of an autoimmune disease, including female predominance, hypergammaglobulinemia, association with specific HLA alleles, responsiveness to immunosuppression, and the presence of autoantibodies. There are several autoantibodies associated with AIH, although the most common are smooth muscle antibodies (SMA). SMA are generally identified by indirect immunofluorescence using a smooth muscle substrate. The antigen specificity of SMA in the context of AIH has been identified as filamentous-actin (F-actin).(2) Because the clinical symptoms of AIH are nonspecific, being found in a variety of liver diseases (drug/alcohol-associated hepatitis, viral hepatitis, primary sclerosing cholangitis, etc), the diagnosis can be challenging. A set of diagnostic criteria for AIH has been published and includes the presence of various autoantibodies, elevated total IgG, evidence of hepatitis on liver histology, and absence of viral markers.(3) The combination of autoantibody serology, specifically SMA and anti-F-actin antibodies with liver histology and thorough clinical evaluation are useful in the evaluation of patients with suspected autoimmune hepatitis.

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.

Negative

Reference values apply to all ages.

Interpretation
Provides information to assist in interpretation of the test results

Seropositivity for smooth muscle antibodies (SMA) is consistent with a diagnosis of autoimmune hepatitis (AIH).

 

A negative result for SMA does not exclude a diagnosis of AIH.

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 smooth muscle antibodies (SMA), should not be relied upon exclusively to determine the etiology or prognosis of patients with liver disease.

 

A positive result for SMA may occur in patients who do not have autoimmune hepatitis. A negative result does not exclude a diagnosis of autoimmune hepatitis.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Mieli-Vergani G, Vergani D, Czaja AJ, et al: Autoimmune hepatitis. Nat Rev Dis Primers. 2018;4:18017

2. Terziroli Beretta-Piccoli B, Mieli-Vergani G, Vergani D: Serology in autoimmune hepatitis: A clinical-practice approach. Eur J Intern Med. 2018;48:35-43

3. Hennes EM, Zeniya M, Czaja AJ, et al: Simplified criteria for the diagnosis of autoimmune hepatitis. Hepatology. 2008;48:169-176

Method Description
Describes how the test is performed and provides a method-specific reference

The patient's serum in 1:20 and 1:40 (initial screening) dilutions is added to fresh tissue from mouse stomach/kidney and incubated; fluorescein-conjugated antiglobulin is then added. The slides are read with a fluorescence microscope.(Package insert: Kallestad Mouse Stomach/Kidney. Bio-Rad Laboratories, Inc; 01/2018)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information

No

Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Saturday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

2 to 4 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

14 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Rochester

Fees
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their Regional Manager. For assistance, contact Customer Service.

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 instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

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 Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.

86015

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports