Test Code TSH RFLX FT4 TSH, Reflex to Free T4
Additional Codes
LAB13042
Collection Method
Venous collection
Minimum Volume
0.5ml
Container
Gold Top SST
Acceptable Specimens
Serum:
- Gold Top SST
- Red Top
Plasma:
- Light Geen Top (lithium heparin)
Reference or Target Ranges
Age | Male | Female |
< 1 month | comment 1 | comment 1 |
1 month to 18 years | 0.5 - 6.0 | 0.5 - 6.0 |
> 18 years | 0.27 - 4.20 | 0.27 - 4.20 |
comment 1- Pediatric reference ranges have not been established by CPH laboratory services
Reportable Units
uIU/mL
Critical Value
Not defined for this assay
Reasons for Rejection
Hemolysis Threshold | 1000 mg/dL |
Icterus Threshold | 41 mg/dL |
Lipemia Threshold | 1500 mg/dL |
Other | QNS, contaminated, improperly Labeled, improper specimen type |
Specimen Stability
Ambient | 8 days |
Refrigerated (4°C to 8°C) | 14 days |
Frozen(-40°C to 0°C) | 2 years |
Performance Information
Days and Time Performed | 24/7 |
Expected Turn Around Time | Stat: 1 hour Routine: 4 hours |
Stat Availability | Yes |
Performing Bench | CPH Chemistry |
Methodology/Method Description | Roche Cobas |
CPT Codes
84443
Last review/edit date
March 2024
Reflex Testing
TSH will reflex to FT4 if result is:
<0.270 or >4.200