Myasthenia gravis profile with reflex-14217

Test info

  
Myasthenia gravis profile with reflex
  
14217
  
LAB14217
  
MGE
  
ACh receptor
  
  • Acetylcholine receptor (AChR)-binding antibodies
  • Acetylcholine Receptor (AChR)-blocking antibodies
  • Acetylcholine Receptor (AChR)-modulating antibodies
  • Striational antibodies

Reflex criteria:

If Acetylcholine Receptor (AChR)-binding, blocking and modulating antibodies are normal, will reflex to Muscle Specific Kinase (MuSK) Antibodies performed at Esoterix Endocrinology Laboratory.

  

Tests for the laboratory diagnosis of myasthenia gravis (MG).

  

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 sample collection

  
Serum
  
  
4.0 mL divided into two (2) aliquot tubes
  
2.0 mL
  
  1. Allow sample to clot for a minimum of 30 to 60 minutes
  2. Spin within two (2) hours of sample collection
  3. Transfer 4.0 mL serum into two (2) a Transfer vial/tube with cap - 12mL (LabCorp), labelled as serum

 

  
  

Immediately following collection, mix sample by gently inverting 5 times

  
  1. Allow sample to clot for a minimum of 30 to 60 minutes
  2. Spin within two (2) hours of sample collection
  

Refrigerated (preferred) - 14 days

Ambient - 7 days

Frozen - 14 days

 

  
One (1) week following testing
  
  • Excessive hemolysis
  • Chylous serum
  • Recently administered radioisotopes
  • Plasma specimen

Performance

  
LabCorp (165620): R-LC
  
Daily
  
7 - 10 days

Clinical and Interpretive info

  

AChR Binding Abs, Serum  nmol/L 

 Negative: 0.00 - 0.24

 Borderline: 0.25 - 0.40

 Positive: >0.40

AChR Blocking Abs, Serum  % 

 Negative: 0 - 25

 Borderline: 26 - 30

 Positive: >30

AChR Modulating Abs, Serum  % 

 Negative: 0 - 45

 Positive: >45

Striation Abs, Serum   Negative

If MuSK Abs reflex: 

  Negative: <1.0;   Positive: 1.0 or higher

  

Acetylcholine receptor autoantibodies are not typically found in congenital myasthenia gravis

Billing

  
86041
86042
86043
86255

Tracking

  
12/06/2019
  
01/04/2024
  
12/21/2023