Leukotriene E4/Creatinine Ratio, Urine
Measures urinary leukotriene E4 relative to creatinine, providing a way to account for urine concentration when evaluating leukotriene release.
["This urine test measures leukotriene E4 activity and may help evaluate suspected mast-cell mediator release when used with other findings."]
Key facts at a glance
- LOINC
- 33343-5
- Short code
- LTE4/Creat Ur
- Synonyms
- LTE4/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?
Leukotriene E4, or LTE4, is a breakdown product of leukotrienes, which are signaling molecules involved in inflammation. This test measures LTE4 in urine and compares it with urinary creatinine, a substance used to account for differences in urine concentration.
Why might I need this test?
A clinician may order this test as an adjunct when evaluating symptoms that could be related to mast-cell activation, such as recurrent flushing, hives, abdominal symptoms, wheezing, or unexplained anaphylaxis. The result is generally interpreted with the medical history, examination, and other laboratory tests because symptoms and urine LTE4 levels can have many causes.
How is the test performed?
A urine sample is collected and tested to determine the amount of LTE4 and creatinine. The laboratory then calculates the LTE4-to-creatinine ratio, which can help reduce the effect of variations in urine concentration.
How do I prepare for the test?
Follow the collection instructions provided by the clinic or laboratory, including whether a single urine specimen or a timed collection is required. Tell your clinician about all medicines, supplements, and recent changes in diet, because some can affect inflammatory markers or urine testing.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
An elevated urine LTE4-to-creatinine ratio may indicate increased leukotriene production, which can occur with mast-cell activation and related inflammatory conditions. A low result or a result that fluctuates does not rule out a mast-cell disorder. Interpretation depends on the collection method, clinical symptoms, medications, diet, and other test results.
Short name
Urine LTE4/Creatinine Ratio
Frequently asked questions
Does this test diagnose mast-cell disease?
Why is creatinine included in the result?
Can medicines or diet affect the result?
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