| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Acetylcholine Receptor Binding Antibody
Test Code206
Alias/See Also
LAB836
ACHR Binding
ACHR Binding
CPT Codes
86041
Preferred Specimen
1 mL serum
Minimum Volume
0.5 mL
Transport Container
Transport tube
Transport Temperature
Room temperature
Specimen Stability
Room temperature: 14 days
Refrigerated: 14 days
Frozen: 30 days
Refrigerated: 14 days
Frozen: 30 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross hemolysis • Grossly lipemic • Microbially contaminated
Methodology
Radioimmunoassay (RIA)
Setup Schedule
Night shift Tues-Sat
Report Available
3-4 days
Limitations
Antibodies may not be found in congenital myasthenia.
Reference Range
| Negative | ≤0.30 nmol/L | |
| Equivocal | 0.31-0.49 nmol/L | |
| Positive | ≥0.50 nmol/L | |
Clinical Significance
Myasthenia Gravis (MG) is an autoimmune neuromuscular disorder characterized by muscle weakness, most commonly due to autoantibody-mediated loss of functional acetylcholine receptors (AChR) in the neuromuscular junction. AChR binding autoantibodies are diagnostic of MG, and are found in 85-90% of MG patients. This assay aids in the differential diagnosis of conditions with MG-like muscle weakness and in monitoring therapeutic response. If binding antibodies are negative, assays for modulating and blocking antibodies should be considered.
Performing Laboratory
| Quest Diagnostics Nichols Institute-San Juan Capistrano, CA |
| 33608 Ortega Highway |
| San Juan Capistrano, CA 92675-2042 |