ARUP's Laboratory Test Directory

0080449: Acetylcholine Receptor Antibody Panel

Test Mnemonic: ACHR PAN
Methodology: Radioimmunoassay and Radioreceptor Assay

Performed: Sun-Sat

Reported: 3-4 days

Specimen Required:  
Collect: One 4 mL SST.

Transport: 1 mL serum at 2-8°C.  (Min: 0.5 mL)  Submit specimen in an ARUP Standard Transport Tube.

Pediatric Collection/Transport: 0.5 mL serum at 2-8°C.

Remarks: Separate serum from cells ASAP.

Unacceptable Conditions: Severely lipemic, contaminated, or hemolyzed specimens.

Stability: After separation from cells: Ambient: 2 hours; Refrigerated: 1 week; Frozen: 1 month (avoid multiple freeze/thaw cycles)

Reference Interval:
 
Test Number Components Reference Interval
0080009Acetylcholine Receptor Binding Antibody Negative: 0.0-0.4 nmol/L
Positive:  0.5 nmol/L or greater
0099580Acetylcholine Receptor Blocking Antibody Negative: 0-15% blocking
Indeterminate: 16-24% blocking
Positive: 25% or greater blocking
0099521Acetylcholine Receptor Modulating Antibody Negative: 0-20% modulation
Indeterminate: 21-25% modulation
Positive:  26% or greater modulation
 

Interpretive Data:
Approximately 85-90% of patients with myasthenia gravis (MG) express antibodies to the acetylcholine receptor (AChR), which can be divided into binding, blocking, and modulating antibody. Binding antibody can activate complement and lead to loss of AChR. Blocking antibody may impair AChR binding to the receptor, leading to poor muscle contraction. Modulating antibody causes receptor endocytosis resulting in loss of AChR expression, which correlates most closely with clinical severity of disease. Approximately 10-15% of individuals with confirmed myasthenia gravis have no measurable binding, blocking, or modulating antibody.

Please refer to Statement B in the Compliance Statements section in the front of the Laboratory Test Directory.



CPT Code(s):
83519 ACHR Binding Ab; 83519 ACHR Blocking Ab; 83519 ACHR Modulating Ab

 

 

 
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