Urine Albumin-to-Creatinine Ratio (Microalbumin-to-Creatinine Ratio)
A urine test that measures albumin relative to creatinine, helping detect small amounts of urinary albumin that may indicate early kidney damage.
["An elevated urine albumin-to-creatinine ratio may be an early sign of kidney damage, especially with diabetes or high blood pressure."]
Key facts at a glance
- LOINC
- 89998-9
- Short code
- Microalbumin/Creat Ur DL<=3.0 mg/L-Rto
- Synonyms
- Microalbumin/Creat Ur DL<=3.0 mg/L-Rto
- Category
- kidney
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Ref low
- 3.5
- Ref high
- 5
- Critical range
- 1.5 N/A – —
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- detection-limit-mg-l
- CPT
- 82040
- SNOMED
- 22383007
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What is this test?
The urine albumin-to-creatininine ratio, sometimes called the microalbumin-to-creatinine ratio, measures how much albumin is present in urine relative to creatinine. Albumin is a protein that should normally be retained by the kidneys.
Why might I need this test?
This test is commonly used to screen for early kidney damage in people with diabetes, high blood pressure, or other kidney-risk conditions. It can detect small increases in urinary albumin before noticeable changes in kidney function are detected.
How is the test performed?
You provide a urine sample, usually a first-morning or other spot urine specimen. The laboratory measures urine albumin and creatinine and calculates their ratio, often reported in milligrams of albumin per gram of creatinine.
How do I prepare for the test?
Fasting is generally not required. Follow the collection instructions provided by your healthcare professional, which may include collecting a clean-catch midstream sample. If a timed collection is requested, be sure to collect all urine for the specified period.
Reference range
Adult: 3.5-5.0 g/dLN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
An elevated ratio can indicate that the kidneys are allowing more albumin to leak into the urine, which may be an early sign of kidney damage. This can occur with diabetes, high blood pressure, and certain other conditions. A single abnormal result should usually be confirmed with repeat testing because temporary factors such as urinary infection, exercise, fever, or high blood sugar can also increase urinary albumin.
Short name
Urine ACR
Frequently asked questions
What does an elevated urine albumin-to-creatinine ratio mean?
Is this the same as a 24-hour urine protein test?
Do I need to have symptoms 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 17, 2026. · Read our editorial policy