Leukotriene E4-to-Creatinine Ratio, 24-Hour Urine
Measures urinary leukotriene E4 relative to creatinine over 24 hours to help evaluate leukotriene production in certain respiratory conditions.
["This test can help identify increased leukotriene production, which may be relevant in some people with asthma or aspirin-triggered respiratory reactions."]
Key facts at a glance
- LOINC
- 101115-4
- Short code
- LTE4/Creat 24h Ur
- Synonyms
- LTE4/Creat 24h 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 substance produced during inflammation involving mast cells and white blood cells. This 24-hour urine test measures LTE4 relative to creatinine, a substance used to account for differences in urine concentration.
Why might I need this test?
The test may be used in selected people with asthma, especially when respiratory symptoms are triggered by aspirin or other anti-inflammatory medicines. It can help assess whether excess leukotriene production contributes to the condition.
How is the test performed?
You collect all urine for exactly 24 hours according to the laboratory's instructions. The laboratory then measures LTE4 and creatinine in the combined urine sample and may report the LTE4-to-creatinine ratio.
How do I prepare for the test?
Follow the laboratory's 24-hour collection instructions carefully, including the start and end times and any refrigeration requirements. Tell your clinician about aspirin, other nonsteroidal anti-inflammatory drugs, and leukotriene-receptor medicines; do not stop prescribed medicines without medical advice.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
An elevated result may indicate increased leukotriene production and can support evaluation of asthma or aspirin-exacerbated respiratory disease. Results should be interpreted with symptoms, medication exposure, collection quality, and other clinical findings. A result within the laboratory's reference interval does not by itself rule out a respiratory disorder.
Short name
24-Hour Urine LTE4-to-Creatinine Ratio
Frequently asked questions
What does the LTE4-to-creatinine ratio show?
Why is urine collected for 24 hours?
Can medicines affect this 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