Urine Tyrosine-to-Creatinine Ratio
A urine test that measures tyrosine relative to creatinine, helping screen for conditions that can cause elevated tyrosine levels.
["This test compares urine tyrosine with creatinine to help identify and monitor conditions associated with increased tyrosine."]
Key facts at a glance
- LOINC
- 13818-0
- Short code
- Tyrosine/Creat Ur
- Synonyms
- Tyrosine/Creat Ur
- Category
- kidney
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What is this test?
The urine tyrosine-to-creatinine ratio measures the amount of tyrosine relative to creatinine in a urine sample. Creatinine is used to account for differences in urine concentration, making results easier to compare between samples.
Why might I need this test?
This test may be used to screen newborns, infants, or other patients for disorders that cause tyrosine to build up in the body. It may also be used to monitor treatment or disease progression when a disorder affecting tyrosine metabolism has already been identified.
How is the test performed?
A urine sample is collected and analyzed in the laboratory to determine the amounts of tyrosine and creatinine. The laboratory then calculates the ratio between them.
How do I prepare for the test?
Follow the collection instructions provided by your healthcare professional or laboratory, including whether a first-morning or other timed sample is required. Be sure to tell the laboratory if you are pregnant, taking medication, or have an illness that could affect the result.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
An elevated ratio may indicate reduced tyrosine metabolism, including hereditary tyrosinemia or certain other metabolic, liver, or nutritional conditions. Interpretation depends on the patient's age, symptoms, diet, medications, and other laboratory findings. A single abnormal result does not by itself establish a diagnosis and is usually confirmed or monitored with additional testing.
Short name
Urine Tyrosine/Creatinine Ratio
Frequently asked questions
Does an elevated urine tyrosine-to-creatinine ratio mean I have tyrosinemia?
Why is creatinine included in this urine test?
Is this the same as a urine protein test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy