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Thiopurine Methyltransferase, RBC

Item Value
Approval req'd? No
Available Stat? No
Test code MOLT (Order in Apex as 'Miscellaneous Outside Lab Test' using the complete test name above)
Performed by Prometheus via Mayo
Sendout? Yes
Method High performance Liquid Chromatography
Collection Instructions Samples may be collected Monday-Friday.
Container type Lavender top
Amount to Collect 5 mL blood
Sample type EDTA whole blood
Preferred volume 5 mL blood
Min. Volume 3.5 mL blood
UCSF Rejection Criteria Samples collected outside of stated time frames
Processing notes Refrigerate whole blood. Do not freeze. Ship refrigerated.
Units Enzyme Units (EU)
Normal range
>21.0 EU Normal Activity
6.0-21.0 EU Intermediate Activity
<6.0 EU Low Activity
Synonyms TPMT; myelotoxicity; TPMT enzyme
Stability Room temperature 1 day, refrigerated 7 days.
Turn around times 5-7 days
CPT coding 82491, 82657
LOINC code 21563-2
Last Updated 2/20/2014 3:20:06 PM
Entry Number 1128
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