Sign in →

Test Code THIO Thiopurine Metabolites, Whole Blood


Shipping Instructions


Specimen must be shipped refrigerated.



Specimen Required


Container/Tube: Lavender top (EDTA)

Specimen Volume: 3 mL

Collection Instructions: Send specimen in original tube. Do not aliquot, centrifuge, or freeze.


Secondary ID

65381

Useful For

Aids physicians in dose adjustments, minimizing dose-dependent toxicity, and monitoring compliance of thiopurine drug therapy

Testing Algorithm

Red blood cell (RBC) count is first performed and then the thiopurine metabolites' values are determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Values are utilized to calculate and report a final result (unit of measure: pmol/8 x 10[8] RBC) for 6-thioguanine nucleotides and 6-methylmercaptopurine derivative analyte.

Method Name

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

Reporting Name

Thiopurine Metabolites, B

Specimen Type

Whole Blood EDTA

Specimen Minimum Volume

1.5 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Whole Blood EDTA Refrigerated (preferred) 8 days
  Ambient  24 hours

Reject Due To

Gross hemolysis Reject
Gross lipemia Reject
Gross icterus Reject
Clotted Reject

Reference Values

6-Thioguanine Nucleotides (6-TGN): 235-450 pmol/8x10(8) RBC

6-Methylmercaptopurine (6-MMP): Less than or equal to 5700 pmol/8x10(8) RBC

Day(s) Performed

Monday through Friday

Report Available

2 to 4 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information

80299

LOINC Code Information

Test ID Test Order Name Order LOINC Value
THIO Thiopurine Metabolites, B 82869-9

 

Result ID Test Result Name Result LOINC Value
49580 6-Thioguanine Nucleotides 32660-3
49581 6-Methylmercaptopurine 32654-6