Urine Leukocyte Esterase and Protein/Creatinine Ratio
These urine tests look for evidence of urinary tract inflammation and measure urine protein relative to creatinine, helping assess kidney involvement.
["Abnormal results may suggest a urinary infection or increased urinary protein loss, depending on which part is abnormal."]
Key facts at a glance
- LOINC
- 79626-8
- Short code
- L-leu-L-pro/Creat Ur-sRto
- Synonyms
- L-leu-L-pro/Creat Ur-sRto
- 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?
Leukocyte esterase is a urine screen for enzyme activity associated with white blood cells. A urine protein-to-creatinine ratio adjusts the amount of urine protein for how concentrated the urine is, making the result easier to interpret.
Why might I need this test?
These tests may be ordered during a urinalysis, when evaluating urinary burning, frequency, urgency, or blood in the urine, or when monitoring certain kidney conditions or protein loss.
How is the test performed?
A urine specimen is collected and tested for leukocyte esterase. The laboratory also measures urine protein and creatinine and calculates their ratio. A urine collection bag or clean-catch method may be used, depending on the situation.
How do I prepare for the test?
Follow the laboratory's collection instructions and tell the clinician if you have a urinary tract infection, take medicines that can affect urine results, or recently received antibiotics. The clinician can explain whether a first-morning or other timed collection is required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A positive leukocyte esterase result may occur with inflammation or infection elsewhere in the urinary tract, but it does not identify the cause by itself. An elevated urine protein-to-creatinine ratio may indicate increased urinary protein loss, which can occur with kidney disease, diabetes, high blood pressure, or inflammation.
Short name
Urine leukocyte esterase and protein/creatinine ratio
Frequently asked questions
Does a positive leukocyte esterase result confirm a urinary tract infection?
Why is urine protein divided by creatinine?
Can exercise or illness temporarily increase urine protein?
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