A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
T4 Free, Direct Dialysis
Test CodeFT4DD
Quest Code
35167
Alias/See Also
35167
CPT Codes
84439
Preferred Specimen
1 mL serum
Patient Preparation
Fasting preferred
Minimum Volume
0.5 mL
Instructions
Please specify the patient's age on the request form
Transport Temperature
Room temperature
Specimen Stability
Room temperature: 4 days
Refrigerated: 14 days
Frozen: 35 days
Refrigerated: 14 days
Frozen: 35 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Lipemia • Heparin plasma • EDTA plasma
Methodology
Equilibrium Dialysis • Chromatography/Mass Spectrometry
FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.
Setup Schedule
Set up: Mon-Sat; Report available: 3-4 days
Report Available
Maximum Laboratory Turn Around Time 7 days
Reference Range
Adult | 0.9-2.2 ng/dL |
Prematures, 25-30 Weeks | |
Birth-7 Days | 0.5-3.3 ng/dL |
Prematures, 31-36 Weeks | |
Birth-7 Days | 1.3-4.7 ng/dL |
Cord Blood, >37 Weeks | 1.2-2.2 ng/dL |
Birth-4 Days | 2.2-5.3 ng/dL |
2 Months-2 Years | 1.2-2.5 ng/dL |
3 Years-17 Years | 1.0-2.4 ng/dL |
Pregnancy | |
First Trimester | 0.9-2.0 ng/dL |
Second Trimester | 0.8-1.5 ng/dL |
Third Trimester | 0.8-1.7 ng/dL |
Clinical Significance
For the differential diagnosis of euthyroid hyperthyroxinemia from hyperthyroidism or for the differential diagnosis of euthyroid hypothyroxinemia from hypothyroidism.
Performing Laboratory
Quest Diagnostics Nichols Institute
33608 Ortega Highway
San Juan Capistrano, CA 92690-6130