TPMT and NUDT15

Test Code

18311

CPT Codes
81306, 81335<br>Restricted Client Code

Preferred Specimen

3 mL whole blood collected in an EDTA (lavender-top) tube, K2 EDTA (pink-top) tube, or ACD-A (yellow-top) tube

Minimum Volume

1 mL

Instructions

Informed consent for genetic testing is required for NY patients.

Transport Temperature

Refrigerated (cold packs)

Specimen Stability

Room temperature: 72 hours
Refrigerated: 7 days
Frozen: 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Plasma or serum • Specimens collected in sodium heparin or lithium heparin • Frozen specimens in glass collection tubes

Methodology
PCRFluorescence Monitoring Sequencing

FDA Status
This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.

Setup Schedule

Set up: Varies; Report available: 5-10 days

Reference Range

See Laboratory Report

Clinical Significance

Use this genotyping test to assess genetic risk for severe myelosuppression with standard dosing of thiopurine drugs in individuals for whom thiopurine therapy is being considered or who have had an adverse reaction to thiopurine therapy. This test may be performed irrespective of whether thiopurine therapy is currently being administered. For enzyme phenotyping prior to thiopurine treatment, refer to Thiopurine Methyltransferase, RBC. For thiopurine dosing optimization, refer to Thiopurine Metabolites in Red Blood Cells.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.