Methotrexate
Test Summary
Methotrexate is an antimetabolite used in the treatment of certain neoplastic diseases, psoriasis and rheumatoid arthritis
Aliases
- Methotrex, Rheumatrex, Trexall, Otrexup, Rasuvo
Specimen Collection
Special Instructions
N/A
Preferred Specimen
1 mL serum
Minimum Volume
1 mL
Instructions
Collection notes: Avoid hemolysis. Invert tubes at least 8 times. Allow to clot in an upright position for 30 minutes. Within 2 hours, centrifuge tubes 10 minutes. Keep tightly stoppered.
Do NOT re-centrifuge tubes. Do NOT freeze the primary collection tube.
Do NOT re-centrifuge tubes. Do NOT freeze the primary collection tube.
Patient Preparation
N/A
Storage
Original tube preferred, may be sent in a screw-top transfer tube.
Transport Temperature
Refrigerated
Specimen Stability
- Room Temperature = 48 hours
- Refrigerated = 14 days
- Frozen = 12 months
Limitations
The ARK Methotrexate assay cross-reacts with DAMPA (2,4-
Diamino-N10-methlypteroic acid), a minor metabolite of
methotrexate. This assay should not be used during therapy with
glucarpidase that rapidly converts circulation methotrexate to
DAMPA.
Other Acceptable Specimens
Plasma from Lithium Heparin (Light Green Top) tube
Unacceptable Specimens
Hemolysis, Lipemia, incorrect specimen type, insufficient sample volume, improper storage conditions, exceeds specimen stability guidelines, contaminated sample.
Order Code
MTX
EPIC (Premier) Code
N/A
Includes
N/A
CPT Code
- 80204
Billing Code
- 500338
CPT Statement
Methodology
Homogeneous Enzyme Immunoassay (EIA)
FDA Status
FDA Approved
Physician Attestation of Informed Consent
N/A
Testing Laboratory
CompuNet Clinical Laboratories, LLC
2308 Sandridge Drive
Moraine OH, 45439
2308 Sandridge Drive
Moraine OH, 45439
Department
Chemistry
Reference Range
See Report
Setup Schedule / Expected Turnaround Time
24/7; Report available: Daily
Specimen Collection
Special Instructions
N/A
Preferred Specimen
1 mL serum
Minimum Volume
1 mL
Instructions
Collection notes: Avoid hemolysis. Invert tubes at least 8 times. Allow to clot in an upright position for 30 minutes. Within 2 hours, centrifuge tubes 10 minutes. Keep tightly stoppered.
Do NOT re-centrifuge tubes. Do NOT freeze the primary collection tube.
Do NOT re-centrifuge tubes. Do NOT freeze the primary collection tube.
Patient Preparation
N/A
Storage
Original tube preferred, may be sent in a screw-top transfer tube.
Transport Temperature
Refrigerated
Specimen Stability
- Room Temperature = 48 hours
- Refrigerated = 14 days
- Frozen = 12 months
Limitations
The ARK Methotrexate assay cross-reacts with DAMPA (2,4-
Diamino-N10-methlypteroic acid), a minor metabolite of
methotrexate. This assay should not be used during therapy with
glucarpidase that rapidly converts circulation methotrexate to
DAMPA.
Other Acceptable Specimens
Plasma from Lithium Heparin (Light Green Top) tube
Unacceptable Specimens
Hemolysis, Lipemia, incorrect specimen type, insufficient sample volume, improper storage conditions, exceeds specimen stability guidelines, contaminated sample.
Result Information
Methodology
Homogeneous Enzyme Immunoassay (EIA)
Testing Laboratory
N/A
Reference Range
See Report
Setup Schedule / Expected Turnaround Time
24/7; Report available: Daily