Test Code ACHRAM Acetylcholine Receptor (Muscle AChR) Binding Antibody, Serum
Additional Codes
MAYO: ARBI
EPIC: LAB836
Reporting Name
ACh Receptor (Muscle) Binding AbUseful For
A first-order test for the laboratory diagnosis of myasthenia gravis (MG)
Detecting "subclinical MG" in recipients of D-penicillamine, in patients with thymoma without clinical evidence of MG, and in patients with graft-versus-host disease
Distinguishing acquired disease (90% positive) from congenital disease (negative)
Monitoring disease progression in MG or response to immunotherapy
An adjunct to the test for P/Q-type calcium channel binding antibodies as a diagnostic aid for Lambert-Eaton myasthenic syndrome (LES) or primary lung carcinoma
Testing Algorithm
This is the primary diagnostic test for myasthenia gravis.
See the following algorithms in Special Instructions:
Myasthenia Gravis Evaluation with MuSK Reflex Algorithm
Myasthenia Gravis/Lambert Eaton Syndrome Diagnostic Algorithm
Myasthenia Gravis: Adult Diagnostic Algorithm
Performing Laboratory

Specimen Type
SerumSpecimen Required
Patient Preparation: This test should not be requested in patients who have recently received radioisotopes, therapeutically or diagnostically, because of potential assay interference. The specific waiting period before specimen collection will depend on the isotope administered, the dose given and the clearance rate in the individual patient. Specimens will be screened for radioactivity prior to analysis. Radioactive specimens received in the laboratory will be held 1 week and assayed if sufficiently decayed, or canceled if radioactivity remains.
Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Specimen Volume: 1.5 mL
Specimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 28 days | |
Frozen | 28 days | ||
Ambient | 72 hours |
Reference Values
≤0.02 nmol/L
Day(s) and Time(s) Performed
Monday through Friday; 11 a.m., 6 p.m., 10 p.m.
Saturday; 6 a.m.
Sunday; 6 a.m., 10 a.m.
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.CPT Code Information
83519
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
ARBI | ACh Receptor (Muscle) Binding Ab | 11034-6 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
8338 | ACh Receptor (Muscle) Binding Ab | 11034-6 |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
Special Instructions
Method Name
Radioimmunoassay (RIA)
Forms
If not ordering electronically, complete, print, and send a Neurology Specialty Testing Client Test Request (T732) with the specimen.