Order Code LABTACB Tacrolimus, Blood
Additional Codes
Mayo Test ID: TAKRO
EPIC Test Code: LABTACB
Reporting Name
Tacrolimus, BUseful For
Monitoring whole blood tacrolimus concentration during therapy, particularly in individuals coadministered cytochrome P450 (CYP) 3A4 substrates, inhibitors, or inducers
Adjusting dose to optimize immunosuppression while minimizing toxicity
Evaluating patient compliance
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
Whole Blood EDTASpecimen Required
Container/Tube: Lavender top (EDTA)
Specimen Volume: 3 mL
Collection Instructions:
1. Draw blood immediately before a schedule dose.
2. Do not centrifuge.
3. Send whole blood specimen in original tube. Do not aliquot.
Additional Information: Therapeutic range applies to trough specimens collected immediately prior to a.m. dose.
Specimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole Blood EDTA | Refrigerated (preferred) | 14 days | |
Ambient | 14 days | ||
Frozen | 14 days |
Reference Values
5.0-15.0 ng/mL (Trough)
Target steady-state trough concentrations vary depending on the type of transplant, concomitant immunosuppression, clinical/institutional protocols, and time post-transplant. Results should be interpreted in conjunction with this clinical information and any physical signs/symptoms of rejection/toxicity.
Day(s) Performed
Monday through Sunday
CPT Code Information
80197
Method Description
Blood specimens are subjected to protein precipitation. The resulting supernatant is analyzed by liquid chromatography tandem mass spectrometry.(Bjergum MW, Jannetto PJ, Langman LJ. Simultaneous determination of tacrolimus and cyclosporine A in whole blood by ultrafast LC-MS/MS. Methods Mol Biol. 2019;1872:111-118. doi:10.1007/978-1-4939-8823-5_11)
Reject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Gross icterus | OK |
Clotted specimens | Reject |
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Forms
If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
-General Request (T239)
-Renal Diagnostics Test Request (T830)
-Therapeutics Test Request (T831)