Urinary Creatinine-to-Creatinine Clearance Ratio (24-hour urine collection)
This test measures how well your kidneys filter waste products from your blood by analyzing urine collected over 24 hours. It helps assess kidney function and blood flow to the kidneys.
["Evaluates kidney function and blood flow through urine analysis over a full day."]
Key facts at a glance
- LOINC
- 10027-1
- Short code
- R' wave dur L-III
- Synonyms
- R' wave dur L-III
- 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
What Does This Test Measure?
The test involves collecting all urine produced in a 24-hour period. Two measurements are taken: creatinine levels in urine and creatinine levels in blood. Creatinine is a waste product from muscle metabolism that kidneys filter out. The ratio helps determine how efficiently your kidneys are working to clear this waste.
Why Might Your Doctor Order This Test?
Your doctor may recommend this test if they suspect kidney disease, monitor chronic kidney disease, evaluate kidney function before certain treatments, or check for conditions affecting blood flow to the kidneys, such as hypertension or diabetes.
How Is This Test Done?
You’ll need to collect every drop of urine for 24 hours, typically starting and ending at the same time each day. A healthcare provider will provide instructions on proper collection and storage. Blood may also be drawn at the start or end of the collection period to measure creatinine levels in your bloodstream.
What Are Common Causes of Abnormal Results?
Low ratios may indicate poor kidney function or reduced blood flow, while high ratios could suggest dehydration, overhydration, or conditions affecting urine concentration. Abnormal results might also reflect muscle disorders, certain medications, or metabolic issues.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is critical for diagnosing and managing kidney-related conditions. It provides insight into how well your kidneys are filtering waste and maintaining fluid balance, which is essential for overall health. Early detection of kidney issues can lead to better treatment outcomes and management of related health problems.
Short name
24h Urine Creatinine Clearance Ratio
Frequently asked questions
What is the typical time frame for receiving results?
Does this test require fasting?
Can I take over-the-counter medications while collecting urine for 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