Test Code TPNUQ Thiopurine Methyltransferase (TPMT) and Nudix Hydrolase (NUDT15) Genotyping, Varies
Additional Codes
Outreach (Atlas) Order Code
TPNUV
Hospital (Cerner) Order Code
TPNUQ
Ordering Guidance
For thiopurine methyltransferase (TPMT) enzyme activity testing, order TPMT3 / Thiopurine Methyltransferase Activity Profile, Erythrocytes; however, this test should also be ordered because TPMT enzyme activity testing cannot detect variants in NUDT15, which also impact thiopurine metabolism.
Specimen Required
Multiple genotype tests can be performed on a single specimen after a single extraction. See Multiple Genotype Test List for a list of tests that can be ordered together.
Submit only 1 of the following specimens:
Specimen Type: Whole blood
Container/Tube: Lavender top (EDTA)
Specimen Volume: 3 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send whole blood specimen in original tube. Do not aliquot.
Specimen Stability Information: Ambient (preferred) 9 days/Refrigerated 30 days
Specimen Type: Saliva
Patient Preparation: Patient should not eat, drink, smoke, or chew gum 30 minutes prior to collection.
Supplies: Saliva Swab Collection Kit (T786)
Specimen Volume: 1 Swab
Collection Instructions: Collect and send specimen per kit instructions.
Specimen Stability Information: Ambient 30 days
Specimen Type: Extracted DNA
Container/Tube: 2-mL screw top tube
Specimen Volume: 100 mcL
Collection Instructions:
1. The preferred volume is 100 mcL at a concentration of 50 ng/mcL.
2. Provide concentration of DNA and volume on tube.
Specimen Stability Information: Frozen (preferred)/Ambient/Refrigerated
Forms
1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available:
-Informed Consent for Genetic Testing (T576)
-Informed Consent for Genetic Testing-Spanish (T826)
2. If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
-Neurology Specialty Testing Client Test Request (T732)
-Gastroenterology and Hepatology Test Request (T728)
-Therapeutics Test Request (T831)
Secondary ID
610062Useful For
Predicting potential for toxicity to thiopurine drugs (6-mercaptopurine, 6-thioguanine, and azathioprine)
Special Instructions
Method Name
Real-Time Polymerase Chain Reaction (PCR) With Allelic Discrimination Analysis
Reporting Name
TPMT and NUDT15 Genotype, VSpecimen Type
VariesSpecimen Minimum Volume
Blood: 0.4 mL
Saliva, extracted DNA: see Specimen Required
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Varies |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
An interpretive report will be provided.
Day(s) Performed
Monday through Friday
Report Available
2 to 4 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
0034U
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
TPNUQ | TPMT and NUDT15 Genotype, V | 93193-1 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
610159 | TPMT Genotype | 41048-0 |
610160 | TPMT Phenotype | 79713-4 |
610161 | NUDT15 Genotype | 93194-9 |
610162 | NUDT15 Phenotype | 93195-6 |
610163 | Interpretation | 69047-9 |
610164 | Additional Information | 48767-8 |
610165 | Method | 85069-3 |
610166 | Disclaimer | 62364-5 |
610167 | Reviewed by | 18771-6 |
Testing Algorithm
For more information see:
-Ulcerative Colitis and Crohn Disease Therapeutic Drug Monitoring Algorithm
-TPMT Testing in the Treatment of Inflammatory Bowel Disease Algorithm