ARUP's Laboratory Test Directory

Thyroglobulin, Serum or Plasma with Reflex to LC-MS/MS or CIA : 2006685
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Additional Technical Information
  


Mnemonic: THYROGRFX

Ordering Recommendation: Recommended test for the surveillance of residual/recurrent thyroid cancer. Accurately measures thyroglobulin levels in serum or plasma.
Methodology: Quantitative Chemiluminescent Immunoassay/High Performance Chromatography-Tandem Mass
Performed: Sun-Sat
Reported: 1-6 days
Specimen Required: Collect: Serum separator tube. Also acceptable: Green (sodium or lithium heparin).

Specimen Preparation: Transfer 3 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 1.5 mL)

Storage/Transport Temperature: Refrigerated.

Unacceptable Conditions: EDTA or K2EDTA Plasma. Any fluid other than noted above. (See Thyroglobulin, Fine Needle Aspiration (FNA) (ARUP test code 0020753) for ordering alternate fluids).

Stability (collection to initiation of testing): After separation from cells: Ambient: 8 hours; Refrigerated: 48 hours; Frozen: 6 months
Reference Interval:
 
Test Number Components Reference Interval
 Thyroglobulin Effective August 20, 2012
 
Age Reference Interval
6 months - 3 years 7.4-48.7 ng/mL
4-7 years 4.1-40.5 ng/mL
8-17 years 0.8-29.4 ng/mL
18 years and older 1.3-31.8 ng/mL
0050105Thyroglobulin Antibody Effective May 7, 2012

0.0-4.0 IU/mL
2006550Thyroglobulin by LC-MS/MS, Serum or Plasma  
 
Age Reference Interval
6 months - 3 years 7.4 - 48.7 ng/mL
4 - 7 years 4.1 - 40.5 ng/mL
8 - 17 years 0.8 - 29.4 ng/mL
18 years and older 1.3 - 31.8 ng/mL
 
Interpretive Data: Specimens negative for thyroglobulin antibodies (TgAb) are tested for thyroglobulin (Tg) by chemiluminescent immunoassay (CIA) using the Beckman Coulter Access DxI method. Specimens with TgAb results above the upper reference limit are tested for Tg by high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results obtained with different test methods or kits cannot be used interchangeably. Tg results, regardless of concentration, should not be interpreted as absolute evidence for the presence or absence of papillary or follicular thyroid cancer. Tg testing is not recommended for use as a screening procedure to detect the presence of thyroid cancer in the general population.

Lower limit of detection for Thyroglobulin by LC-MS/MS is 0.5 ng/mL.
Note: The reflex testing method (CIA or LC-MS/MS) is determined by the TgAb result. Additional charges apply.
CPT Code(s): 86800; 84432