Test ID: ZG975
CPT code: 82657
LOINC:
Specimen Type: Green-top (sodium heparin) tube or Lav (EDTA) tube
Frequency: 7 – 12 days
Instructions: 8 mL adult; 5 mL pediatric, Whole Blood from Green-top (sodium heparin) tube or Lav (EDTA) tube, Refrigerated. Min 5 mL.
Text: Determination of TPMT levels that may be associated with toxicity of anticancer and anti-inflammatory drugs. For patients having an intrinsic low level of TPMT, recent RBC transfusion can variably increase their assayed enzymatic activity depending on the amount and circulating half-life of the transfused red blood cells.
Methodology: Enzymatic endpoint/liquid chromatography/tandem mass spectrometry (LC/MS-MS)