Test Code MTX Methotrexate
Performing Laboratory
| Women and Children's Hospital Laboratory | 304-388-2385 |
Specimen Requirements
Dark Green Lithium Heparin
Specimen Rejection
- Improperly labeled, collected, stored, and transported
- Quantity not sufficient
Storage and Stability
| Refrigerated 2-8oC | 2 weeks |
| Frozen <-20oC | Undetermined |
Reference Values
Methotrexate levels in excess of 50 mcmol/L at 24 hours, 10 mcmol/L at 48 hours, and 0.5 mcmol/L at 72 hours potential toxicity. Methotrexate values should be used in conjunction with information available from clinical evalution and other diagnostic procedures. NOTE: This assay should not be used if patient is receiving possible compassionate therapy with glucarpidase.
Methodology
Homogeneous competitive enzyme immunoassay
Days Test Set Up and Turnaround
Monday through Sunday, Continuously
| AM Collection | Expected by 9AM same day |
| Routine | Expected within 24 hrs |
| Stat | Expected within 1 hr |
| Timed | Expected results are test dependant |
CPT Coding
80299