Test Code MTX Methotrexate Level
Patient Preparation
No special patient preparation required
Special Collection Instructions
Customarily, draw at 24 hour intervals after start of infusion; although earlier and more frequent monitoring may be indicated.
Collection Method
Venous collection
Minimum Volume
1 mL
Container
Lt Green / Plasma Separator / Lithium Heparin
Preferred Specimen
Light Green Top (lithium heparin) plasma
Acceptable Specimens
Serum:
- Gold Top SST
- Red Top
Plasma:
- Light Geen Top (lithium heparin)
- Purple or Pink Top(K2/K3 EDTA)
- Dark Green Top (sodium heparin)
Reference or Target Ranges
<0.05 umol/L
Therapeutic ranges depend on specimen collection time after dose and protocol applied.
Reportable Units
umol/L
Critical Value
N/A
Reasons for Rejection
<!-- Rejection-->
Hemolysis Threshold | 1000 mg/dL |
Icterus Threshold | 60 mg/dL |
Lipemia Threshold | 700 mg/dL |
Other | QNS, contaminated, improperly Labeled, improper specimen type |
Specimen Stability
<!-- Stability -->
Ambient | 8 hours |
Refrigerated (4°C to 8°C) | 7 days |
Frozen(-40°C to 0°C) | 12 months |
Performance Information
<!-- Performance information -->
Days and Time Performed | 24/7 |
Expected Turn Around Time | Stat: 1 hour Routine: 4 hours |
Stat Availability | Yes |
Performing Bench | UH Chemistry |
Methodology/Method Description | Siemens Atellica - ImmunoAssay |
CPT Codes
80204