Acetylcholine Receptor (AChR) Binding Ab-994
Test info
ACRAB
Myasthenia gravis antibody
ACh receptor
In vitro diagnostic semiquantitative determination of autoantibodies against the acetylcholine receptor in human serum and plasma. This assay is the primary test for confirming the diagnosis of acquired Myasthenia gravis.
In rare cases AChR antibodies can be found in patients with other autoimmune disorders or with thymoma without MG.1
The causative autoantibody cannot be identified in up to 10 percent of patients with MG.
Specimen
No isotopes administered 24 hours prior to venipuncture.
(Note: This volume does not allow for repeat testing.)
Immediatley following collection, mix sample by gently inverting 5 times
- Allow sample to clot for a minimum of 30 minutes
- Spin within 45 minutes of collection
Gold serum separator (SST) tube
- Allow sample to clot
- Spin within 45 minutes of collection
- Transfer serum to a Transfer vial/tube with cap - 12mL (LabCorp) labelled as serum
Ambient (preferred) - 14 days
Refrigerated - 14 days
Frozen - 14 days
Freeze/thaw cylces - 3
- Gross hemolysis
- Gross icterus
- Gross lipemia
Performance
This assay measures antibodies that precipitate solubilized muscle AChR that has been complexed with radiolabeled alpha-bungarotoxin (αBTX).
Antibodies that bind to the receptor regions that are not sterically blocked by the αBTX are detected.
Clinical and Interpretive info
Negative: 0.00 - 0.24 nmol/L