Home
HelpTest Code TRYPU Tryptophan, Random, Urine
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Reporting Name
Tryptophan, USpecimen Type
UrineOrdering Guidance
Other body fluids are not acceptable specimens for this test. For testing spinal fluid specimens, order AACSF / Amino Acids, Quantitative, Spinal Fluid.
Testing for tryptophan using plasma specimens is available; order TRYPP / Tryptophan, Plasma.
Necessary Information
1. Patient's age is required.
2. Include family history, clinical condition (asymptomatic or acute episode), diet, and drug therapy information.
Specimen Required
Supplies: Urine Tubes, 10 mL (T068)
Container/Tube: Plastic, 10-mL urine tube
Specimen Volume: 2 mL
Collection Instructions: Collect a random urine specimen.
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Urine | Frozen (preferred) | 70 days | |
| Refrigerated | 14 days |
Specimen Minimum Volume
1 mL
Day(s) Performed
Monday through Friday
Specimen Retention Time
2 weeksReport Available
3 to 5 daysReference Values
<2 months: <241 nmol/mg creatinine
2-35 months: <329 nmol/mg creatinine
3-6 years: <222 nmol/mg creatinine
7-17 years: <218 nmol/mg creatinine
≥18 years: <140 nmol/mg creatinine
Useful For
Aiding in the screening and monitoring of Hartnup disease
CPT Code Information
82131
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| TRYPU | Tryptophan, U | 28608-8 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 83823 | Tryptophan, U | 28608-8 |
| 34618 | Interpretation (TRYPU) | 59462-2 |
| 113131 | Reviewed By | 18771-6 |
Forms
If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.