Test Code TSHR TSH REFLEX
Methodology
Chemiluminescent Immunometric Assay (Ultrasensitive)
If TSH is <0.465 µIU/mL or >4.68 µIU/mL, free thyroxine (T4) will be performed at an additional charge.
Useful as a primary screening test for thyroid function.
Specimen Requirements
Submit only 1 of the following specimens:
Preferred:
Serum Gel Tube
Container/Tube: Serum gel tube(s)
Specimen Volume: 2 mL (minimum volume: 1 mL) of
serum
Collection Instructions: Spin down within 4 hours of draw.
Alternate:
Plain, Red-Top Tube
Container/Tube: Plain, red-top tube(s)
Specimen Volume: 2 mL (minimum volume: 1 mL) of
serum
Collection Instructions: Spin down within 4 hours of draw.
Day(s) Test Set Up
Monday through Friday
Reference Values
< 3 Days 1.00 – 20.0
3 – 30 Days 0.50 – 6.50
1 Month – 5 Months 0.50 – 6.00
≥ 6 Months 0.47 – 4.68 µIU/mL
Performing Laboratory
Logan Health Medical Center-Chemistry
Test Classification and CPT Coding
84443-TSH
84439-Free T4 (if appropriate)
Specimen Transport Temperature
Refrigerate