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HelpTest Code LAB10226 TSH Reflex to FT4
Profile Information
| Test Code | Test Name | Methodology |
Available Separately |
Always Performed |
|---|---|---|---|---|
| LAB129 | Thyroid-Stimulating Hormone (TSH) | Electrochemiluminescence Immunoassay (ECLIA) | Yes | Yes |
Testing Algorithm:
If TSH is normal, testing stops.
If TSH is low, then FT4 is performed at an additional charge.
If TSH is high, then FT4 is performed at an additional charge.
Reflex Test
| Test Code | Test Name |
Available Separately |
Always Performed |
|---|---|---|---|
| LAB127 | Free T4 (Thyroxine) | Yes | No |
Performing Laboratory
Bozeman Health Laboratory Services
Specimen Requirements
Specimen Type: Plasma or serum
Container/Tube: Light-green top (lithium heparin gel), red top, or gold top
Specimen Volume: 1 mL
Specimen Minimum Volume: 0.5 mL
Specimen Rejection: Samples should not be taken from patients receiving therapy with high
biotin doses (i.e. > 5 mg/day) until at least 8 hours following the last biotin
administration.
Specimen Transport Temperature
Ambient/Refrigerated
Specimen Stability
| Specimen Type | Temperature | Time |
|---|---|---|
| Plasma or Serum | Ambient | 5 days |
| Refrigerated | 7 days | |
| Frozen | 30 days |
Reference Values
| Test Name | Reference Value |
|---|---|
| TSH | 0.34-4.82 µIU/mL |
| Free T4 | 0.8-1.5 ng/dL |
Methodology
Electrochemiluminescence Immunoassay (ECLIA)
Day(s) Performed
Monday through Sunday
CPT Coding
84443-TSH
84439-T4, free (if appropriate)