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Test Code
THXAB
Test Name
Thyroxine Antibody
CPT Codes
83516
Expected Turnaround Time
Varies
Clinical Utility

This test helps identify thyroxine (T4) thyroid hormone autoantibodies (THAAbs), which may interfere with T4 immunoassays in individuals with discordant serum T4 levels.

The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.
Specimen and Container Info

Specimen Type: Serum

Collection Container: Red Top, Plain

Desired Specimen Volume: 1 mL
Collection Instructions
  1. Collect a red top, plain tube via venipuncture.
Processing and Submission Instructions
  1. Separate serum from cells within 2 hours of collection.
  2. Transfer 1 mL of serum to a clear aliquot tube (screw cap).
Transport Instructions

Transport to the laboratory refrigerated.  
Stability Requirements

Room Temperature

14 days

Refrigerated

14 days

Frozen

28 days
Causes for Rejection
  • Plasma
  • Gross hemolysis
  • Gross lipemia
Methodology
Radiobinding Assay (RBA)
Reference Intervals

See patient report.
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Routine, 2 times per week
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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