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Test Code RT3 T3 (Triiodothyronine), Reverse, Serum


Specimen Required


Supplies: Sarstedt Aliquot Tube, 5 mL (T914)

Collection Container/Tube:

Preferred: Red top

Acceptable: Serum gel

Submission Container/Tube: Plastic vial

Specimen Volume: 0.8 mL

Collection Instructions: Centrifuge and aliquot serum into a plastic vial.


Children's Mercy Hospital Note:

CMH COLLECTION: 2 mL in red gel vacutainer

Specimen Minimum Volume

0.4 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 28 days
  Ambient  28 days
  Frozen  28 days

Useful For

Aiding in the diagnosis of the sick euthyroid syndrome

Reject Due To

Gross hemolysis Reject
Gross lipemia OK
Gross icterus OK

Day(s) Performed

Monday through Friday

Report Available

2 to 6 days

Reporting Name

T3 (Triiodothyronine), Reverse, S

Reference Values

10-24 ng/dL

Method Name

Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)

Portions of this test are covered by patents held by Quest Diagnostics.

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information

84482