Test Overview
Test Methodology

Enzyme Immunoassay (EIA)

Test Usage

Useful in the diagnosis of myasthenia gravis (MG) in older patients, especially when anti-acetylcholine receptor antibodies are negative; serological aid in the diagnosis of thymoma, especially in patients with onset of MG at ages < or = to 45 yrs; monitoring the efficacy of immunosuppressive treatment in patients with MG.

Reference Range *

Negative (Titer < 1:120)

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

A negative result does not exclude the presence of thyoma (20% are negative).

Test Details
Days Set Up
Monday - Saturday
Analytic Time

4 - 6 days

Soft Order Code
STR
Synonyms
  • Myasthenia Gravis Antibody
  • Myoid Antibody
  • Skeletal Muscle Antibody
  • Striated Muscle Ab
  • Striated Muscle Antibody
  • STR
  • STRIATED MUSCLE ANTIBODIES
Laboratory
Sendout
Reference Laboratory
Mayo STR (8746)
Section
Special Testing
Test Updated
09/02/2020
Update Type
Test Resumed
Specimen Requirements
Collection Instructions

Collect blood in a red top or SST tube. Centrifuge, aliquot serum into a plastic vial and refrigerate or freeze.

Yellow Top Tube
Normal Volume
1.5 mL serum
Minimum Volume
1 mL serum
Additional Information

May occasionally be seen in patients with thymoma without myasthenia gravis. In myasthenia, titers correlate with severity, activity, progression, and rapidity of onset of the disease. About 35% of persons with myasthenia gravis (MG) will show a presence of antibodies. Patients with both MG and thymoma almost always show a positive result. Test sent to Mayo Medical Laboratories.

Billing
CPT Code
83520
Fee Code
30966
LOINC
8097-8
Resources