Sign in →

Browse by Name

  1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H
  9. I
  10. J
  11. K
  12. L
  13. M
  14. N
  15. O
  16. P
  17. Q
  18. R
  19. S
  20. T
  21. U
  22. V
  23. W
  24. X
  25. Y
  26. Z
  27. #
 

The University of Chicago Medicine Laboratories

Links

Announcements

Specimen Collection and Handling

Transfusion

Forms

 

 

 

 

Mayo Clinic Laboratories

Test Code TPMT3 Thiopurine Methyltransferase Activity Profile, Erythrocytes

Important Note

Order LABRFPMTSS in Epic

 

Secondary ID

65188

Method Name

Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)

Specimen Type

Whole blood


Specimen Required


Patient Preparation: Thiopurine methyltransferase (TPMT) enzyme activity can be inhibited by several drugs and may contribute to falsely low results. Patients should abstain from the following drugs for at least 48 hours prior to TPMT testing: naproxen (Aleve), ibuprofen (Advil, Motrin), ketoprofen (Orudis), furosemide (Lasix), sulfasalazine (Azulfidine), mesalamine (Asacol), olsalazine (Dipentum), mefenamic acid (Ponstel), trimethoprim (Proloprim), methotrexate, thiazide diuretics, and benzoic acid inhibitors.

Container/Tube:

Preferred: Lavender top (EDTA)

Acceptable: Green top (sodium or lithium heparin), dark blue top (metal free sodium heparin), or non-centrifuged plasma gel tubes

Specimen Volume: 5 mL

Collection Instructions: Send whole blood specimen. Do not centrifuge.


Specimen Minimum Volume

3 mL

Specimen Stability Information

Specimen Type Temperature Time
Whole blood Refrigerated (preferred) 6 days
  Ambient  6 days

Reject Due To

Gross hemolysis Reject

Reference Values

6-Methylmercaptopurine (normal): 3.00-6.66 nmol/mL/h

6-Methylmercaptopurine riboside (normal): 5.04-9.57 nmol/mL/h

6-Methylthioguanine riboside (normal): 2.70-5.84 nmol/mL/h

Day(s) Performed

Monday, Wednesday, Friday

Report Available

4 to 7 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information

84433

Forms

1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available:

-Informed Consent for Genetic Testing (T576)

-Informed Consent for Genetic Testing-Spanish (T826)

2. If not ordering electronically, complete, print, and send Gastroenterology and Hepatology Test Request (T728) with the specimen