Test Code N.TSH.FT4RFLX TSH W/REFLEX FT4
Additional Codes
N.TSH.FT4R.FLX
Methodology
Automated Chemistry Analyzer
Specimen Requirements
Serum or Plasma
Container: SST tube or Green top Lithium heparin
Specimen Collection: 1 mL (minimum 0.5 mL)
- Allow specimen to clot completely if a serum tube (SST) was used.
- Separate serum (SST) or plasma (Lithium Heparin) from cells within 24 hours and transport refrigerated. If red top tube is collected, separate serum from cells within 2 hours and place in separate plastic tube.
- Properly label tube with patient's name, DOB, requisition number and type of tube, i.e. GREEN.
Alternate Specimens: Red top tube (Serum) or K2EDTA Plasma
Specimen Transport/Stability
Refrigerated: 24 hours on gel, 7 days poured off
Specimen Rejection
1. Exceeding stability requirements
2. Unlabeled specimen
Maximum Laboratory Time
24 - 48 hours
Reference Ranges
TSH | mcIU/mL |
Newborn | 2.00 - 7.00 |
1 mo | 0.00 - 5.00 |
15 yrs | 0.35 - 4.94 |
Reflex Condition: | Abnormal TSH |
Day(s) Test Set Up
Daily
Test Classification and CPT Coding
84443
Reflex:
FT4
84436