Creatinine Clearance (from 24-hour urine collection)
This test measures how well your kidneys filter waste products from your blood, using a 24-hour urine sample. It helps assess kidney function and blood pressure management.
["Helps doctors check kidney health and blood pressure control over 24 hours."]
Key facts at a glance
- LOINC
- 48230-7
- Short code
- CATDLR
- Synonyms
- Cat Dander LR-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Heparinized (sodium heparin) or EDTA blood collection tube for leukocyte isolation; serum separator tube (SST) if processed serum is required
- Units
- N/A
- Ref low
- 200
- Ref high
- 500
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 1–99 years
- Method
- Leukocyte stimulation assay with cat dander allergen; quantitative measurement of leukotriene release from peripheral blood leukocytes via enzyme immunoassay (EIA) or liquid chromatography-tandem mass spectrometry (LC-MS/MS)
- CPT
- 86003
- SNOMED
- 39579001
- Specimen volume
- 5-10 mL of whole blood; minimum 3 mL
- Stability
- Whole blood stable at room temperature (18-25°C) for up to 4 hours after collection. Isolated leukocytes or processed specimens should be analyzed within 24 hours when stored at 2-8°C. For prolonged storage beyond 24 hours, freeze at -20°C or below; avoid repeated freeze-thaw cycles.
- Hemolysis max
- 100
- Lipemia max
- 150
- Icterus max
- 50
- TAT
- 48–120 hours
- Order
- routine
What Does This Test Measure?
Creatinine clearance evaluates how efficiently your kidneys remove creatinine, a waste product from muscle metabolism. Unlike a single blood test, this 24-hour urine method accounts for daily fluid intake and output, giving a more complete picture of kidney function.
Why Might You Need This Test?
Your doctor may order this test if you have chronic kidney disease, high blood pressure, diabetes, or if you’re taking medications that affect kidney function. It’s also used to monitor kidney health before surgeries or during certain treatments.
How Is This Test Done?
You’ll collect all urine for a full 24-hour period in a special container. Your doctor will provide instructions to ensure accuracy. Blood and urine samples may be taken at the start and end of the period to confirm results.
What Are Common Results Used For?
Results help determine if your kidneys are filtering waste properly. Low clearance may indicate kidney damage, while high values could signal dehydration or other conditions. It’s often compared to your blood creatinine levels for a full assessment.
Reference range
Negative: < 200 pg/mL; Equivocal: 200-500 pg/mL; Positive: > 500 pg/mL. Reference values may vary by laboratory and assay manufacturer.N/A
No special preparation required. Patient should be informed that the test evaluates cellular (non-IgE mediated) hypersensitivity to cat dander allergens. Avoid antihistamine use for at least 48 hours prior to testing if recommended by ordering physician, as antihistamines may interfere with leukocyte responsiveness. Discontinue systemic corticosteroids only under physician guidance.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
24-Hour Urine Creatinine Clearance
Frequently asked questions
How often will I need this test?
What do my results mean if they’re outside the normal range?
Can I eat or drink normally before 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 15, 2026. · Read our editorial policy