This test assists in the diagnosis of autoimmune myasthenia gravis (MG) with acetylcholine receptor (AChR) antibodies. This is the first-line test in our MG antibody panel.

Test Code:



In-house radioimmunoprecipitation


Laboratory developed test (LDT)


Specimen type


Minimum volume

0.5 mL

Preferred volume

3 mL

Rejection criteria

Grossly hemolytic, lipemic, or icteric. If the sample arrives at room temperature.


Specimen collection

No patient preparation is required for sample collection.
Draw blood in tube(s) with SST activator (5mL gold top or 8.5mL tiger top).
Invert tubes 8 times to ensure complete mixing.

Specimen handling

Centrifuge SST tubes at 1800 - 2200 x g for 10-15 minutes
Draw off serum (top layer) into Aliquot tubes with pipette, ensuring not to take gel or RBC (middle/bottom layers)
Store Aliquot tubes in refrigerator (2°C - 8°C) until shipping.

specimen stability

Serum samples may be stored:
Up to 7 days at room temp (15 - 25°C)
Up to 4 weeks refrigerated (2 - 8°C)
Up to 2 freeze / thaw


Testing frequency

Once per week (2-day procedure)

Turnaround time

2-8 days

Reference range

Negative: 0.0 – 0.2 nmol/L
Borderline: 0.2 – 2 nmol/L
Positive: > 2 nmol/L

Additional Information

  • This test was developed and its performance determined by Neurocode USA Inc. It has not been cleared or approved by the Food and Drug Administration.
  • Please indicate if patients are on immunomodulating treatments as these may interfere with testing.
  • Causal antibodies cannot be identified in about 10% of MG cases. Therefore, a positive result is specific for the diagnosis of AChR ab myasthenia gravis (MG), but a negative result does not rule out an MG diagnosis.