Test Catalog

Test ID: MUSK    
Muscle-Specific Kinase (MuSK) Autoantibody, Serum

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

Diagnosis of autoimmune muscle-specific kinase (MuSK) myasthenia gravis


Second-order test to aid in the diagnosis of autoimmune myasthenia gravis when first-line serologic tests are negative


Establishing a quantitative baseline value for MuSK antibodies that allows comparison with future levels if weakness is worsening


Second-line test aiding diagnosis of autoimmune myasthenia gravis (MG) in patients with new onset acquired MG evident clinically and electrophysiologically but negative first-line serological tests (acetylcholine receptor: AChR binding and modulating antibodies).


A positive result, in the appropriate clinical context, confirms the diagnosis of autoimmune muscle-specific kinase myasthenia gravis.

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

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

Radioimmunoassay (RIA)

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

MuSK Autoantibody, S

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