ARUP's Laboratory Test Directory

Acetylcholine Receptor Modulating Antibody : 0099521

Mnemonic: ACHRMOD

Methodology: Radioreceptor Assay
Performed: Mon-Sat
Reported: 2-7 days
Specimen Required: Collect:  One 4 mL serum separator tube.

Transport:  0.5 mL serum at 2-8°C. (Min: 0.3 mL)  Submit specimen in an ARUP Standard Transport Tube.

Pediatric Collection/Transport:  0.3 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:
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
 
 

 

 

 
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