Test Code LAB1823 Methotrexate Level
Performing Section
Chemistry
Purpose/Principle
Quantitatively measure Methotrexate levels in plasma and serum.
Special Collection Notes
Protect sample from light.
Specimen Type
Serum/Plasma:
Light Green Tube Top-Lithium Heparin (Preferred)
Gold Top Tube-SST
Red Top Tube-Plain
Specimen Volume
Preferred: 0.9 mL (0.3 mL Serum/Plasma)
Minimum: 0.6 mL (0.04 mL Serum/Plasma)
Processing Instructions
CENTRIFUGE sample per procedure.
Store and send sample refrigerated via courier.
Temperature
Refrigerated
Test Components
Hemolysis Index
Icterus Index
Turbidity Index
Methotrexate Level
Methotrexate Level- Diluted (AVG)
Methotrexate Last Dose Start Date
Methotrexate Last Dose Start Time
Methotrexate Last Dose Stop Date
Methotrexate Last Dose Stop Time
MTX Dil 1
MTX Dil 2
MTX Quality Check
Reference Range
Hemolysis IndexThis component has no reference ranges
Icterus Index
This component has no reference ranges
Turbidity Index
This component has no reference ranges
Methotrexate Level
>=0.04 mcmol/L
Methotrexate Level- Diluted (AVG)
>=0.04 mcmol/L
MTX Dil 1
>=0.04 mcmol/L
MTX Dil 2
>=0.04 mcmol/L
MTX Quality Check
-10.0-10.0 %
TAT
Routine: 120 Minutes
STAT: 75 Minutes
Sample Stability
Ambient: Not recommended
Refrigerated: 14 days
Frozen @-18 Celsius: 8 months (do not exceed 3 freeze/thaw cycle)
Additional Notes
Patients on glucarpidase rescue therapy should be off the drug for 5 to 7 days prior to methotrexate testing. Patients given
glucarpidase may have an increased value for methotrexate.
Aliases
MTX
CPT
80204
Test/Batch Schedule
Runs daily-on demand