Test Code Lab876 Tacrolimus (FK506), Blood
Additional Codes
LAB876
Methodology
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Performing Laboratory
Barnes-Jewish Hospital Laboratory
Specimen Requirements
Specimen Type: Whole blood
Container/Tube: Lavender top (EDTA)-Separator gel tube is not acceptable.
Specimen Volume: Full tube
Collection Instructions:
Do not centrifuge.
1. Draw blood for trough level immediately prior to next dose.
2. Label specimen appropriately (peak, trough, random).
Additional Information: Date and time of draw are required.
Specimen Transport Temperature
Ambient
Reference Values
Results are reported in ng/mL.
The therapeutic range for tacrolimus can vary by transplant organ type and sample timing but a trough range of 5 - 15 ng/mL is typical.
Day(s) Test Set Up
Monday through Sunday
Cut-off time: 2330, 0600, 0900, 1200, 1530
Turnaround Time:
STAT: not available
Routine: 3 hours after cut-off time
Test Classification and CPT Coding
80197-Each
Additional Information
For BJH Laboratory Use Only
Alternate Tube(s):
1 pediatric, lavender-top (EDTA) tube
Analyte Stability:
- Specimens must be processed within 7 days.
- Processed sample stability:
- Ambient - 7 days
- Refrigerated (2 - 8°C) - 7 days
- Frozen (≤ -20°C) - 2 weeks
Mix freshly collected, refrigerated, or thawed specimen thoroughly prior to use. Avoid repeated freezing and thawing.
- See Analyte Stability Chart under General Information for a complete list.
Laboratory Processing Instructions:
Test performed in BJH Core Lab. Log in and place in the pending specimen refrigerator. Do not centrifuge. Do not freeze. Completed specimen is stored refrigerated for 5 days.
LOINC Code Information
Name | LOINC Code |
Tacrolimus | 74097-7 |
Tacrolimus Trough | 77348-1 |