Ordering Recommendation

Acceptable reflexive panel for diagnosing myasthenia gravis. Includes acetylocholine receptor (AChR) binding and blocking antibodies, titin anibodies, and striated muscle antibodies, with possible reflex to AChR modulating antibodies or striated muscle antibody titer.

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation
Collect

Plain red top or Serum Separator Tube (SST).

Specimen Preparation

Transport 1.5 mL serum. (Min. 0.7 mL) Separate serum from cells ASAP or within one hour of collection. Transfer to an ARUP Standard Transport Tube.

Storage/Transport Temperature

Refrigerated. Frozen is also acceptable. 

Unacceptable Conditions

Plasma. Hemolyzed, lipemic, moderately icteric serum or contaminated specimens.

Remarks

Repeated freeze-thaw cycles should be avoided.

Stability

Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year

Methodology

Quantitative Radioimmunoassay/Semi-Quantitative Enzyme-Linked Immunosorbent Assay/Semi-Quantitative Indirect Fluorescent Antibody/Semi-Quantitative Flow Cytometry

Performed

Mon-Fri

Reported

1-8 days

Reference Interval

Test Number
Components
Reference Interval
  Striated Muscle Antibodies, IgG Screen Less than 1:40
  Acetylcholine Binding Antibody 0.4 nmol/L or less
  Acetylcholine Blocking Antibody 26 or less blocking
  Titin Antibody 0.45 IV or less

Interpretive Data

Refer to report.

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.


Component Interpretation
Acetylcholine Receptor Binding Antibody Negative
Positive
0.0-0.4 nmol/L
0.5 nmol/L or greater
Acetylcholine Receptor Blocking Antibody Negative
Indeterminate
Positive
0-26% blocking
27-41% blocking
42% or greater blocking
Acetylcholine Receptor Modulating Antibody Negative
Positive
0-45% modulating
46% or greater modulating
Titin Antibody Negative
Indeterminate
Positive
0.00-0.45 IV
0.46-0.71 IV
0.72 IV or greater

Compliance Category

Laboratory Developed Test (LDT)

Note

If Acetylcholine Receptor Binding Antibody result is greater than 0.4 nmol/L or Acetylcholine Receptor Blocking Antibody result is greater than 26 percent, then Acetylcholine Receptor Modulating Antibody will be added. If Striated Muscle Ab is detected, then a titer will be added. Additional charges apply.

Hotline History

N/A

CPT Codes

86041; 86042; 83516; 86255; if reflexed, add 86043; 86256

Components

Component Test Code* Component Chart Name LOINC
0050747 Striated Muscle Antibodies, IgG Screen 49692-7
0080009 Acetylcholine Binding Antibody 11034-6
0099580 Acetylcholine Blocking Antibody 42937-3
2005637 Titin Antibody 100371-4
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.

Aliases

  • AChR Binding Antibody
  • AChR Antibody
  • Anti-Skeletal Muscle IgG Antibodies
  • Anti-Striated Antibody
  • anti-tintin Ab
  • Muscle (Skeletal) Antibodies
  • Muscle nicotinic Acetylcholine Receptor
  • Myasthenia Gravis Antibodies
  • Myoid Antibody
  • Skeletal Muscle Antibodies
  • Striational Antibodies
Acetylcholine Receptor Antibodies and Striated Muscle Antibodies Reflexive Panels, and Titin Antibody