Urinary Creatinine to Creatinine Clearance Ratio (24-hour urine)
This test measures the ratio of creatinine in your urine over a 24-hour period to help assess how well your kidneys are filtering waste products from your blood.
["This test helps evaluate kidney function by comparing urine creatinine levels to a baseline measurement."]
Key facts at a glance
- LOINC
- 9940-8
- Short code
- Q wave dur L-I
- Synonyms
- Q wave dur L-I
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- ekg
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Your healthcare provider may order this test if they suspect kidney disease, poor kidney function, or if you have symptoms like swelling, fatigue, or changes in urine output. It can also be used to monitor kidney health in people with chronic conditions like diabetes or high blood pressure.
How the Test Works
You’ll collect all urine for a full 24-hour period in a container. The urine is then sent to a lab for analysis. The test compares the amount of creatinine in your urine to a standard reference value, often derived from blood creatinine levels.
What to Expect Before the Test
No special preparation is needed, but you may be asked to drink extra fluids to ensure adequate urine production. Avoid certain medications that could affect kidney function before testing if instructed by your provider.
What the Results Mean
A lower ratio than expected may indicate kidney problems, while a higher ratio could suggest dehydration or other conditions. Your results will be interpreted by your healthcare provider in the context of your overall health.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This ratio helps doctors diagnose and monitor kidney-related issues by assessing how well your kidneys are filtering waste. Abnormal results may signal early kidney damage or dysfunction, prompting further evaluation or treatment adjustments.
Short name
None
Frequently asked questions
What is a normal range for this test?
How often should I get this test?
Can diet or medications 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