Kidney Function: Urine Albumin-to-Creatinine Ratio (24-hour collection)
This test measures the amount of albumin (a protein) and creatinine (a waste product from muscles) in your urine over 24 hours. It helps assess how well your kidneys are filtering blood and detecting early signs of kidney damage.
["A 24-hour urine test for albumin-to-creatinine ratio helps track kidney health and early kidney disease risk."]
Key facts at a glance
- LOINC
- 15287-6
- Short code
- Width Kidney-L US.meas
- Synonyms
- Width Kidney-L US.meas
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- us-measured
- 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 Matters for Kidney Health
Kidneys filter waste and excess substances from your blood, including proteins like albumin. High albumin levels in urine can signal kidney damage or conditions like diabetes or high blood pressure. This test is especially useful for monitoring kidney function in people with risk factors for kidney disease.
How the Test Works
You’ll collect all your urine for 24 hours in a special container. The lab measures the ratio of albumin to creatinine in your urine sample. This ratio helps doctors determine if your kidneys are working properly or if protein is leaking into your urine.
What to Expect Before the Test
No special preparation is needed, but you’ll need to collect every drop of urine for 24 hours. Drink enough fluids to produce urine throughout the day, but avoid excessive alcohol or caffeine, which may affect results.
What to Expect During the Test
You’ll return the 24-hour urine sample to your lab or clinic. The lab will process it to measure albumin and creatinine levels, then calculate the ratio. Results are typically ready within a few days.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated albumin in urine (microalbuminuria) can indicate early kidney damage, often linked to diabetes or hypertension. A normal ratio suggests healthy kidney function, while higher ratios may signal kidney strain. Regular monitoring with this test helps manage kidney health and prevent progression of kidney disease.
Short name
Albumin:Creatinine Ratio (Urine, 24h)
Frequently asked questions
What does a high or low ratio mean?
Does diet affect this test?
How often should I get 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