Thiopurine Methyltransferase (TPMT) Enzyme Activity

Synonyms

  • 6 MERCAPTOPURINE
  • LAB10814
  • THIOPURINE METHYLTRANSFERASE (TPMT) ENZY
  • TPMT ERYTHROCYTES
  • TPMT-RBC
  • TPMTENZ

Cerner Name

TPMT Enzyme

Clinical Info

Determination of TPMT levels that may be associated with toxicity of anticancer and anti-inflammatory drugs

Specimen Sources

Blood, Arterial Blood, Capillary Blood, Central Line Blood, Venous

Specimen Types

Blood

Specimen Volume

8 mL Whole Blood adults

Container

Lavender Top Tube

Collection Instructions

Container/ Tube: 2  Lavender top (EDTA
Specimen:  8 mL Whole Blood adults
                    5 mL Whole Blood pediatric
                    Minimum: 5 mL Whole Blood
Transport Temperature: Refrigerated whole blood (Stable 14 days)

Transport Instructions

Refrigerated whole blood (Stable 14 days)

Specimen Stability

Methodology

Enzymatic endpoint/liquid chromatography/tandem mass spectrometry (LC/MS-MS).

Days Performed

Performing Laboratories

LabCorp of America

CPT

82657
 
Loinc Code: 21563-2

PDM

5906029

Results
Component Name Base Name Common Name External Name
TPMT ENZYME TPMTEZY TPMT ENZYME TPMT Activity
TPMT ENZYME INTERPRETATION TPMTEZYINT TPMT ENZYME INTERPRETATION TPMT Activity Interpretation
TPMT ENZYME METHODOLOGY TPMTEXMET TPMT ENZYME METHODOLOGY TPMT Activity Methodology

Result Interpretation

• Normal: 15.1−26.4 units/mL RBC
• Heterozygous for low TPMT variant: 6.3−15.0 units/mL RBC
• Homozygous for low TPMT variant: <6.3 units/mL RBC

Forms
Tox/TDM LAB10814 build edit