Methotrexate by LCMSMS

General Information

Lab Name
Methotrexate by LCMSMS
Lab Code
MTXG1
Epic Name
Methotrexate Level
Description

The concentration of methotrexate in serum or plasma is determined by liquid chromatography-tandem mass spectrometry after protein precipitation. The reportable range is 0.01 to 2,000 mcmol/L with imprecision between 3 and 14 %CV.

Components

Interpretation

Method

Serum/plasma protein precipitation. Analysis by liquid chromatography - tandem mass spectrometry.

Reference Range
See individual components

Ordering & Collection

Specimen Type
Blood
Collection

Preferred: 3 mL blood in GREEN, RED, or LAVENDER TOP tube

Acceptable: 3 mL blood in GOLD SST or LIME PST tube

Quantity
Requested: 0.7 mL serum/plasma
Minimum: 0.5 mL serum/plasma

Processing

Receiving Instructions

Remove serum or plasma from the gel separator within 4 hours of collection. Refrigerate aliquot tube.

Stability: Methotrexate in serum is stable up to 5 days when refrigerated. Avoid exposure to daylight.

Misc Sendout

Performance

Lab Department
Chemistry, University(CHU)
Frequency
Daily, specimens must be in the lab by 09:00am for same day results
Available STAT?
No
Performing Location(s)
UW-MT Chemistry, Special
206-520-4600

Clinical Lab, Room NW220,
University of Washington Medical Center,
1959 NE Pacific street, Seattle, WA 98195

Billing & Coding

CPT Codes
80204
LOINC
14836-1
Interfaced Order Code
UOW2749