ARUP's Laboratory Test Directory

Acetylcholine Receptor Modulating Antibody : 0099521

Mnemonic: ACHRMOD

Methodology: Semi-Quantitative Radioreceptor Assay
Performed: Sun-Fri
Reported: 2-7 days
Specimen Required: Collect: Serum separator tube.

Specimen Preparation: Separate serum from cells ASAP or within 2 hours of collection. Transfer 0.5 mL serum to an ARUP Standard Transport Tube. (Min: 0.3 mL)

Storage/Transport Temperature: Refrigerated.

Unacceptable Conditions: Contaminated, hemolyzed, or severely lipemic specimens.

Stability (collection to initiation of testing): After separation from cells: Ambient: 2 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated 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 antibodies. Binding antibody can activate complement and lead to loss of AChR. Blocking antibody may impair binding of acetylcholine 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 antibodies.

Refer to Statement B under Testing Information at http://www.aruplab.com.
CPT Code(s): 83519
Cross References: Myasthenia Gravis Antibodies (Acetylcholine Receptor Modulating Antibody)
 
 

 

 

 
All ARUP Sites:        www.aruplab.com     ·     www.arupconsult.com     ·     www.arup.utah.edu     ·     www.childx.org     ·     www.utahblood.org