Referred Tests
| Web: | mayocliniclabs.com |
|---|---|
| Email: | mcl@mayo.edu |
| Telephone: | 800-533-1710 |
| International: | +1 855-379-3115 |
| Values are valid only on day of printing. | |
Test ID: MGRM
Myasthenia Gravis (MG) Evaluation with MuSK Reflex, Serum
Useful For 
Suggests clinical disorders or settings where the test may be helpful
Diagnosis for autoimmune myasthenia gravis (MG) in adults and children
Distinguishing autoimmune from congenital MG in adults and children
Establishing a quantitative baseline value that allows comparison with future levels if weakness is worsening
Highlights
Seropositivity confirms a clinical or electrophysiologic diagnosis of autoimmune myasthenia gravis (MG).
Second-line muscle-specific kinase (MuSK) antibody test positivity confirms a clinical or electrophysiologic diagnosis of autoimmune MG where first-line serological tests (acetylcholine receptor: AChR binding and modulating antibodies) are negative.
Profile Information A profile is a group of laboratory tests that are ordered and performed together under a single Mayo Test ID. Profile information lists the test performed, inclusive of the test fee, when a profile is ordered and includes reporting names and individual availability.
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| MGRMI | MG Interpretive Comments | No | Yes |
| ARBI | ACh Receptor (Muscle) Binding Ab | Yes | Yes |
| STR | Striational (Striated Muscle) Ab, S | Yes | Yes |
| ARMO | ACh Receptor (Muscle) Modulating Ab | No | Yes |
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 |
|---|---|---|---|
| MUSK | MuSK Autoantibody, S | Yes | No |
| GD65S | GAD65 Ab Assay, S | Yes | No |
| GANG | AChR Ganglionic Neuronal Ab, S | No | No |
| VGKC | Neuronal (V-G) K+ Channel Ab, S | No | No |
| CRMWS | CRMP-5-IgG Western Blot, S | Yes | No |
Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
If acetylcholine receptor (AChR) modulating antibodies are > or =90% and striational antibodies are > or =1:120, then ganglionic AChR neuronal autoantibody, glutamic acid decarboxylase autoantibody, neuronal voltage-gated potassium channel autoantibody, and collapsin response-mediator protein-5 (CRMP-5)-IgG Western blot will be performed at an additional charge.
If AChR-binding antibodies are < or =0.02 and AChR-modulating antibodies are < or =20%, then muscle-specific kinase (MuSK) autoantibody will be performed at an additional charge.
See Myasthenia Gravis Evaluation with MuSK Reflex Algorithm in Special Instructions.
Special Instructions Library of PDFs including pertinent information and forms related to the test
Method Name A short description of the method used to perform the test
ARBI, ARMO, GANG, VGKC: Radioimmunoassay (RIA)
STR: Enzyme Immunoassay (EIA)
CRMWS: Western Blot
NY State Available Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name Lists a shorter or abbreviated version of the Published Name for a test
Aliases Lists additional common names for a test, as an aid in searching
Ach Receptor Ab
AChR Receptor Blocking Ab
AChR (Acetylcholine Receptor)
Anti-Skeletal Muscle Antibodies
Binding, Blocking, and Modulating Abs
Blocking Ab
GAD65 (Glutamic Acid Decarboxylase)
Glutamate Decarboxylase Antibodies (GAD65)
Muscle End-Plate Antibodies
Myasthenia Gravis
Myasthenia Gravis Antibodies
MuSK myasthenia
Myoid Antibody
Neuronal Potassium Channel Ab
Potassium Channel Antibodies (specify)
Thymoma
VGKC
VGPC
Voltage-Gated Potassium Channel Ab
MUSK