TRAb (TSH Receptor Binding Antibody)

TSH Receptor Ab, TSH-Binding Inhibiting Immunoglobulin, Thyrotropin Receptor Antibody (TRAb), Thyrotropin Receptor Antibody, Serum

Test Codes

EPIC: LAB1232041, Beaker: TBII, Quest: 38683

Department

Send Outs

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 plastic transport tube and maintain at room temperature (20-26°C or 68-78.8°F) prior to transport.

Preparation for Courier Transport

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

Rejection Criteria

• Grossly hemolyzed specimens.
• Specimens not collected and processed as indicated.

In-Lab Processing

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

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

Storage

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): Unacceptable
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): 3 months

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.

Laboratory

Sent to Quest Diagnostics, Wood Dale, IL.

Performed

Monday – Saturday.
Results available in 2-4 days.

Reference Range

By report.

Test Methodology

Quantitative Electro Chemiluminescent Immunoassay.

Interpretation

• TSH Receptor Antibodies are measured in this assay by the thyrotropin binding inhibiting immunoglobulin technique (TBII). Results are reported as percent inhibition of TSH binding.
  
• Positive results are consistent with autoimmune thyroid disease.

Clinical Utility

The TSH receptor antibody (TRAb) assay aids in the differential diagnosis of Graves' disease (positive in > 85%) versus toxic nodular goiter. TRAb levels aid the clinician in prescribing the most appropriate course of therapy upon initial diagnosis. This assay is also used to monitor the efficacy of anti-thyroid drug therapy to predict the likelihood of disease remission.

CPT Codes

83520

Contacts

Last Updated

12/17/2025