CPT Code for TSH Receptor Antibodies
The CPT code for TSH receptor antibody (TRAb) testing is 83520 (Immunoassay for analyte other than infectious agent antibody or infectious agent antigen; quantitative, not otherwise specified).
Understanding the Test and Coding
While the provided evidence focuses extensively on the clinical utility and diagnostic performance of TRAb assays in Graves' disease 1, the specific CPT coding is standardized through the American Medical Association's Current Procedural Terminology system.
Key Points About TRAb Testing:
Modern assays use either competitive binding immunoassays (measuring all TSH-R antibodies regardless of function) or bioassays that specifically measure thyroid stimulating immunoglobulin (TSI) function 2, 3
Third-generation assays using monoclonal antibody M22 or similar techniques show clinical sensitivity and specificity approaching 100% for Graves' disease diagnosis 1, 4, 5
Both TRAb and TSI assays are strongly correlated (r=0.873) and show good clinical agreement, making paired ordering of both tests redundant and potentially wasteful 3, 6
Clinical Context:
The guidelines emphasize that anti-TSH-R antibody assay is recommended as first-line testing when Graves' disease is suspected, particularly in typical presentations (young female, ophthalmopathy, homogeneous goiter), where positive results provide near 100% positive predictive value 1.
Common pitfall: Some laboratories may use different CPT codes depending on the specific methodology (competitive binding vs. bioassay), so verify with your specific laboratory's billing department for their preferred coding, as some may use 86376 (Microsomal antibodies) or other codes depending on their interpretation of the test methodology.