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Test Code
TTGAB
Test Name
tTg IgA Autoantibody
CPT Codes
86364
Included Tests

Tissue Transglutaminase (tTG) IgA Autoantibody.
Expected Turnaround Time
3 - 7 days
Clinical Utility
  • Useful first-order screening test for celiac disease.
  • Identifying individuals that should have a biopsy for celiac disease.
  • Monitoring adherence to gluten-free diet in patients with dermatitis herpetiformis and celiac disease.
  • Evaluating children with failure to thrive.
Specimen and Container Info

Preferred Specimen Type: Serum

Desired Specimen Volume: 2 mL

Preferred Collection Container: Gold Top, Serum Separator
Processing and Submission Instructions

Separator tubes: Contains clot activator and gel for separating serum from cells, but not anticoagulant. Separate serum from cells as soon as the clot has formed (30 minutes). If specimen is centrifuged before clotting is complete, a fibrin clot will form on top of the cell. This may cause the gel barrier to not be intact and could cause improper separation of serum and cells, possibly affecting test results.
Transport Instructions

Transport refrigerated. 
Stability Requirements

Refrigerated

7 days

Frozen

<20°C for long-term storage. 

Freeze/Thaw Cycles

Avoid multiple freeze/thaw cycles. 
Methodology
Semi-Quantitative Multiplex Bead Assay
Reference Intervals

< 20 U/mL
Performing Location
Roble Road Core Laboratory
Testing Schedule
Routine, Monday - Friday no holidays
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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