Tests

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T3, Free (Triiodothyronine)

Test Name:T3, Free (Triiodothyronine)
Epic Order Code:LAB137
CPT Code:84481  
Specimen(s) Type:Plasma or Serum, 0.5 mL
Acceptable Container(s):Tube tops are light green and gold.
Testing Schedule:24 hrs/day, 7 days/week
Turn Around Time:STAT: 1 hour  
 Routine: 2 hours
Collection Information:No special patient preparation is required. Obtain specimen by standard collection procedures.
Transport Information:Deliver to lab immediately. All specimens must be signed into the laboratory.
Reference Clients:If unable to deliver to the lab within 1 hour, centrifuge the specimen and remove plasma/serum from the red cells. Store and transport at 2-8° C. Specimen must be received in the lab within 24 hours.
Causes for Rejection:Improperly labeled, incorrect container, contaminated, insufficient quantity, incorrect/delay in transport.
Reference Range:0 - 4 days: 197 - 787 pg/dL
 4 days - 2 mos: 196 - 524 pg/dL
 2 mos - 2 yrs: 155 - 638 pg/dL
 2 - 7 yrs: 196 - 595 pg/dL
 7 - 12 yrs: 268 - 516 pg/dL
 12 - 19 yrs: 228 - 501 pg/dL
 > 19 yrs: 200 - 440 pg/dL
Additional Information:Any influence that might affect the binding behavior of the binding proteins can alter the result of the Free T3 tests, i.e., drugs, NTIs (Non-Thyroid Illness) or patients suffering from FDH (Familial Dysalbuminemic Hyperthyroxinemia).
 Autoantibodies to thyroid hormones can interfere with the assay.