ARUP's Laboratory Test Directory

Acetylcholine Receptor Antibody Reflexive Panel : 2001571
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Additional Technical Information
  


Mnemonic: ACHR R PAN

Methodology: Quantitative Radioimmunoassay/Semi-Quantitative Radioimmunoassay/Semi-Quantitative Flow Cytometry
Performed: Sun-Sat
Reported: 3-7 days
Specimen Required: Collect: Serum separator tube.

Specimen Preparation: Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.5 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:
Effective August 20, 2012
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: 0-45% modulating
Positive: 46% or greater modulating

Effective August 20, 2012

Interpretive Data: Approximately 85-90 percent 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 percent of individuals with confirmed myasthenia gravis have no measurable binding, blocking, or modulating antibodies.

See Compliance Statement B: www.aruplab.com/CS
Note: If Acetylcholine Receptor Binding Antibody result is greater than 0.4 nmol/L or Acetylcholine Receptor Blocking Antibody result is greater than 15 percent, then Acetylcholine Receptor Modulating Antibody (ARUP test code 0099521) will be added. Additional charges apply.
CPT Code(s): 83519; 83516; if reflexed, add 83516
Cross References: Myasthenia Gravis Antibodies (Acetylcholine Receptor Antibody Reflex Panel)