Creatinine Clearance (Serum-Based, 24-Hour Urine Collection)
This test measures how well your kidneys filter waste products from your blood, using a 24-hour urine sample and your serum creatinine level. It helps assess kidney function and overall kidney health.
["A creatinine clearance test helps doctors check how well your kidneys are working by measuring how quickly waste products leave your blood."]
Key facts at a glance
- LOINC
- 72953-3
- Short code
- Sildenafil cit (neut) IgM SerPl Ql FC
- Synonyms
- Sildenafil cit (neut) IgM SerPl Ql FC
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- flow-cytometry
- CPT
- 82784
- 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 doctor may order this test if they suspect kidney disease, monitor kidney function over time, or evaluate kidney damage from conditions like diabetes, high blood pressure, or certain medications. It’s also used before surgeries or procedures that may affect kidney function.
What to Expect Before the Test
You’ll need to collect all urine for a full 24-hour period (typically from one morning to the next morning). Your doctor or lab will provide instructions. On the day of testing, you’ll provide a blood sample (serum) to measure creatinine levels. Avoid excessive fluid intake on the day of blood draw if instructed.
What Happens During the Test
The 24-hour urine collection involves emptying your bladder completely at the start of the period, then collecting every drop of urine for the full 24 hours. The blood test is a simple finger-prick or vein draw. Results are calculated by comparing your serum creatinine with the urine creatinine and volume.
What the Results Mean
Results are expressed in milliliters per minute (mL/min) or milliliters per second (mL/s). Lower than expected values may indicate kidney problems, while higher values could suggest dehydration or muscle breakdown. Your doctor will interpret results in the context of your overall health.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Creatinine clearance is a key indicator of kidney function. It helps diagnose chronic kidney disease, monitor progression, and guide treatment for conditions like diabetes or hypertension. Abnormal results may signal early kidney damage that requires medical attention.
Short name
Creatinine Clearance
Frequently asked questions
How long does the 24-hour urine collection take?
Can I eat or drink normally during the urine collection?
What if I miss any urine during the 24-hour period?
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