Epic Code LAB1231928 Acetylcholine Receptor Modulating Antibody

Test Name Alias

LAB1231688 | Quest: 26474 | ACHR MOD AB | Myasthenia Gravis (MG), AChR modulating antibody

Interface Order Alias

1231928

Clinical Information

Acetylcholine Receptor Modulating Antibody - Myasthenia Gravis (MG) is an autoimmune neuromuscular disorder characterized by muscle weakness, most commonly due to autoantibody-mediated loss of functional acetylcholine receptors (AChR) in the neuromuscular junction. AChR binding autoantibodies are diagnostic of MG, and are found in 85-90% of MG patients. AChR modulating antibodies cross-link AChR molecules on cell surface, promoting internalization, and decreasing AChR surface density. The AChR binding and modulating antibody assays have similar sensitivities, but performing them together increases sensitivity of antibody detection by approximately 5%.

Specimen Requirements

Specimen Collection Criteria

Collect (preferred specimen): One Gold-top SST tube.
Also acceptable: One plain Red-top tube.

Physician Office/Draw Specimen Preparation

Let specimen clot 30-60 minutes then centrifuge to separate serum from cells. Transfer serum to a plastic transport tube and keep at room temperature (20-26°C or 68-78.8°F)

In-Lab Processing

Let specimen clot 30-60 minutes then centrifuge to separate serum from cells. Transfer serum to a plastic transport tube and keep at room temperature (20-26°C or 68-78.8°F)

Specimen Transport Temperature

1.0 mL serum, room temperature (20-26°C or 68-78.8°F). (Minimum: 0.5mL)

Rejection Criteria

Plasma
Gross hemolysis.
Grossly lipemic.
Microbially contaminated.
Specimens not collected and processed as indicated.

Specimen Stability

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 14 daysRefrigerated (2-8°C or 36-46°F): 14 days
Frozen (-20°C/-4°F or below): 30 days

Specimen Storage in Department Prior to Disposal:

Specimen retention time is determined by the policy of the reference laboratory. Contact the Send Outs Laboratory with any questions.

Test Frequency

Performed: Sunday, Tuesday, Thursday.
Results available in 4-8 days.

Reference Range

<32 % Inhibition

Performing Department

Send Outs

Performing Department Laboratory Location

Sent to Quest Diagnostics Nichols Institute- San Juan Capistrano, CA.

Methodology

Radiobinding Assay (RBA)

CPT

86043

LOINC

Unavailable

Reviewed Date

10/31/2025

Orderable Regions