Test directory: TPMT Activity Profile, Erythrocytes

Ordering Code7924
Test NameTPMT Activity Profile, Erythrocytes
AliasThiopurine Methyltransferase Activity Profile,
Erythrocytes
TPMT RBC
TPMT Enzyme
Preferred SpecimenWhole Blood
Preferred ContainerEDTA, K2 (Lavender) 6 mL
Other Specimen/ContainerWhole Blood in Lithium Heparin (Green), Whole Blood in
Sodium Heparin (Green)
Optimum Volume5 mL
Collection InstructionsPatients 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.
Transport RequirementsOahu: Ambient
Airline: Refrigerated
Specimen StabilityAmbient: 6 Days
Refrigerated: 6 Days
Frozen: Not Stable
Rejection CriteriaGrossly hemolyzed
Avail. StatNO
Analytic Time6 Days
MethodologyLiquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Reference Lab Mayo Medical Lab

Reference range(s)

The reference ranges listed below are valid on this date of May 3, 2024.
ComponentAgeMale NormMale Critical LowMale Critical HighFemale NormFemale Critical HighFemale Critical LowUnitsAdd'l info
InterpretationALLSee report.
6-MethylmercaptopurineALLSee report.
6-Methylmercaptopurine ribosideALLSee report.
6-Methylthioguanine ribosideALLSee report.
Reviewed ByALLSee report.