Mobile Site ›
Print Friendly View

Test ID: MGEA    
Myasthenia Gravis (MG) Evaluation, Adult

Secondary ID A test code used for billing and in test definitions created prior to November 2011

83370

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

Yes

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

Initial evaluation of patients aged 20 or older with symptoms and signs of acquired myasthenia gravis (MG)

 

Bone marrow transplant recipients with suspected graft-versus-host disease, particularly if weakness has appeared

 

Confirming that a recently acquired neurological disorder has an autoimmune basis (eg, MG)

 

Providing a quantitative baseline for future comparisons in monitoring a patient's clinical course and the response to immunomodulatory treatment

 

Raising likelihood of neoplasia

 

If muscle acetylcholine receptor (AChR) modulating antibody value is (or exceeds) 90% AChR loss and striational antibody is detected, thymoma is likely. Reflexive testing will include collapsin response-mediated protein-5-lgG Western blot, ganglionic AChR antibody, glutamic acid decarboxylase (GAD65) antibody, and voltage-gated potassium channel complex (VGKC) antibody (which are frequent with thymoma).

 

Note: Single antibody tests may be requested in follow-up of patients with positive results documented in this laboratory.

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 IDReporting NameAvailable SeparatelyAlways Performed
ARBIACh Receptor (Muscle) Binding AbYesYes
ARMOACh Receptor (Muscle) Modulating AbNoYes
STRStriational (Striated Muscle) Ab, SYesYes

Reflex Tests Lists test(s) that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial test(s)

Test IDReporting NameAvailable SeparatelyAlways Performed
GD65SGAD65 Ab Assay, SYesNo
CRMWSCRMP-5-IgG Western Blot, SNoNo
GANGAChR Ganglionic Neuronal Ab, SNoNo
VGKCNeuronal (V-G) K+ Channel Ab, SNoNo

Testing Algorithm Delineates situation(s) 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 AChR ganglionic neuronal autoantibody, glutamic acid decarboxylase autoantibody, neuronal voltage-gated potassium channel autoantibody, and collapsin response-mediated response-5-IgG Western blot will be performed at an additional charge.

 

See Myasthenia Gravis: Adult Diagnostic Algorithm in Special Instructions.

Special Instructions and Forms Describes specimen collection and preparation information, test algorithms, and other information pertinent to test. Also includes pertinent information and consent forms to be used when requesting a particular test

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

ARBI, ARMO, GANG, GD65S, VGKC: Radioimmunoassay (RIA)

STR: Enzyme Immunoassay (EIA)

CRMWS: Western Blot

Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name

MG Evaluation, Adult

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

Acetylcholine Receptor (Muscle AChR) Antibodies
AChR (Acetylcholine Receptor)
Anti-Skeletal Muscle Antibodies
GAD65 (Glutamic Acid Decarboxylase)
Muscle End-Plate Antibodies
Myasthenia Gravis Antibodies
Myoid Antibody
Neuronal Potassium Channel Ab
Striational (Striated Muscle) Antibodies
VGKC
VGPC
Voltage-Gated Potassium Channel Ab
Potassium Channel Antibodies (specify)
Glutamate Decarboxylase Antibodies (GAD65)
Ach Receptor Ab
Blocking Ab
ACh Receptor Blocking Ab
Binding, Blocking, and Modulating Abs