Muscle Specific Kinase (MUSK) Autoantibody, Serum
Order Code:
MUSK
Test Summary
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.
Aliases
- N/A
Specimen Collection
Special Instructions
N/A
Preferred Specimen
1.5 mL serum from a red top tube
Minimum Volume
1 mL
Instructions
N/A
Patient Preparation
N/A
Storage
Plastic screw-cap vial
Transport Temperature
Refrigerated
Specimen Stability
- Room Temperature: 72 hours
- Refrigerated: 28 days
- Frozen: 28 days
Limitations
Immunosuppressant therapy is a common cause of false-seronegativity. It is, therefore, important to perform a comprehensive serological evaluation before initiating immunosuppressant therapy. Interpretation of a patient’s serological and clinical status is further complicated when characteristic signs of myasthenia gravis are obscured by a superimposed steroid-induced myopathy.
Other Acceptable Specimens
Serum from a serum separator tube
Unacceptable Specimens
Gross hemolysis, gross lipemia, gross icterus
Order Code
MUSK
EPIC (Premier) Code
LAB6427
Includes
N/A
CPT Code
- 86366
Billing Code
- 650022
CPT Statement
Methodology
Radioimmunoassay (RIA)
FDA Status
This test was developed using an analyte specific reagent. Its performance characteristics were 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.
Physician Attestation of Informed Consent
N/A
Testing Laboratory
Mayo Clinic Laboratories
200 First Street SW
Rochester MN, 55905
200 First Street SW
Rochester MN, 55905
Department
Reference Testing
Reference Range
N/A
Setup Schedule / Expected Turnaround Time
Monday - Friday; Report available: 3 - 10 days
Specimen Collection
Special Instructions
N/A
Preferred Specimen
1.5 mL serum from a red top tube
Minimum Volume
1 mL
Instructions
N/A
Patient Preparation
N/A
Storage
Plastic screw-cap vial
Transport Temperature
Refrigerated
Specimen Stability
- Room Temperature: 72 hours
- Refrigerated: 28 days
- Frozen: 28 days
Limitations
Immunosuppressant therapy is a common cause of false-seronegativity. It is, therefore, important to perform a comprehensive serological evaluation before initiating immunosuppressant therapy. Interpretation of a patient’s serological and clinical status is further complicated when characteristic signs of myasthenia gravis are obscured by a superimposed steroid-induced myopathy.
Other Acceptable Specimens
Serum from a serum separator tube
Unacceptable Specimens
Gross hemolysis, gross lipemia, gross icterus
Result Information
Methodology
Radioimmunoassay (RIA)
Testing Laboratory
N/A
Reference Range
N/A
Setup Schedule / Expected Turnaround Time
Monday - Friday; Report available: 3 - 10 days