About the Test
Purpose of the test
The purpose of this test is to determine if there is an abnormal amount of the protein albumin in a urine sample.
Excess albumin on this type of test indicates that too much of this protein has passed from the blood to the urine, which can reflect a kidney problem. Different types of urine albumin tests can be used for diagnosis, screening, and monitoring of kidney disease.
This includes medical exams or tests done after symptoms have appeared. A urine albumin test may be included in the diagnostic process if you notice health changes that kidney problems could cause.
Examples of symptoms related to kidney impairment include urinary irregularities such as frothy urine, blood in the urine, or changes in urine volume or frequency. Abnormal swelling, itching, loss of appetite, and fatigue can also occur due to kidney problems.
These tests are designed to try to find health problems before symptoms occur to enable treatment before a disease has significantly progressed. Because the early stages of kidney disease may not cause symptoms, urine albumin tests are often used to look for indications of kidney problems.
A urine albumin-to-creatinine ratio test is a common way to screen for high albumin levels, known as albuminuria. This screening is most often done if you have a higher risk of kidney disease, including diabetes, high blood pressure, or a family history of kidney problems. Screening may also be recommended for older adults and people in some racial and ethnic groups.
A screening for kidney disease may combine a urine albumin test with another kidney function test, known as an estimated glomerular filtration rate (eGFR) test, that assesses how well the kidneys are filtering the blood.
The presence of high or very high levels of albumin in the blood has also been associated with cardiovascular disease, obesity, and diabetes so urine albumin testing may provide information about risks related to these conditions and their potential complications.
Another use of urine albumin tests is for monitoring kidney health over time. This often means using repeat urine albumin tests at regular intervals to check how kidney disease is progressing or to see how well treatments work.
What does the test measure?
A urine albumin test is a measurement of the protein albumin. It is produced by the liver and is a common protein in the blood that helps keep fluid from leaking out of blood vessels. Albumin also helps carry substances, including enzymes and vitamins, through the body.
While albumin is supposed to be found in the blood, very little should enter the urine if the kidneys are functioning properly. Different types of urine albumin tests are designed to detect albumin in the urine:
- A urine dipstick test has a test strip that turns a different color based on the amount of albumin in the sample.
- A 24-hour urine sample requires collecting all of your urine for a full day. The laboratory then measures the total amount of albumin in that complete sample.
- An albumin-to-creatinine ratio test measures both albumin and creatinine in a one-time sample, also known as a “spot” urine sample. Creatinine is a chemical byproduct of normal muscle activity normally removed from the body in urine. Total daily creatinine production is relatively consistent, so this ratio test is an alternative way to estimate your total daily urine albumin level without doing a full 24-hour urine sample.
A dipstick test does not provide an exact measurement of albumin. The result is only a semi-quantitative value.
A 24-hour urine sample provides an albumin measurement typically listed as milligrams per 24 hours (mg/24 hours).
An albumin-to-creatinine ratio test is reported in milligrams of albumin per gram of creatine (mg/g) found in one deciliter of urine. This may also be listed in international units measured in milligrams per millimole (mg/mmol).
Some laboratories or health professionals may report urine albumin test results using an estimated albumin excretion rate (eAER). This calculation has a formula that incorporates the albumin-to-creatinine ratio with the ability to adjust the expected daily creatinine level based on individual factors such as body composition, age, sex, and race. While not broadly used, the eAER may be most beneficial if you have abnormal daily creatinine production.
When should I get this test?
Urine albumin tests can be used in several different medical contexts.
For diagnosis, they are generally performed if you have signs of possible kidney impairment. Urinary changes, swelling, and unexplained itching are examples of symptoms that can be associated with kidney problems. In these cases, a urine albumin test and other kidney function tests may be performed.
Screening with a urine albumin test is only recommended for some people. If you don’t have risk factors for kidney disease, the downsides of this testing, including financial costs and potential unnecessary follow-up, are considered to be greater than the potential benefits. As such, this screening is not recommended in the population in general.
Instead, screening is usually reserved if you have a higher risk of kidney problems. Urine albumin testing is recommended if you have diabetes; this testing may be done every year if you have type 2 diabetes.
Screening is also advised if you have one or more of the following risk factors for kidney disease:
- High blood pressure
- A family history of chronic kidney disease
- Cigarette smoking
- Cardiovascular disease
- Belonging to certain racial or ethnic groups
If you have had an abnormal albumin level in your urine or have been diagnosed with kidney disease in the past, you may have repeat testing to monitor your urine albumin levels. In these cases, the doctor may request 24-hour urine samples to more precisely measure the amount of albumin.
Finding a Urine Albumin or Albumin-to-Creatinine Ratio Test
How can I get a urine albumin or albumin-to-creatinine ratio test?
A doctor normally orders testing for urine albumin levels. Your doctor can recommend either a dipstick, spot urine sample, or 24-hour urine collection based on your health situation, including whether you have any symptoms or risk factors for kidney disease.
Dipstick tests may be performed in a doctor’s office, health clinic, or hospital. Spot urine samples can also be collected in these medical settings. A 24-hour urine sample involves collecting all your urine in special containers over a full day.
Dipstick tests are a kind of point-of-care test, which means they provide results on-site and without having to send the sample to a lab. Point-of-care devices exist for measuring albumin in a spot urine sample, but these devices are not widely available. A laboratory analyzes most spot urine samples and virtually all 24-hour urine collections.
Can I take the test at home?
Some types of urine albumin tests can be taken at home. At-home test kits generally fall into two categories:
- Self-test kits: These allow you to take and analyze the sample at home. The kits are dipstick tests in which a special paper or test strip is dipped into a cup of urine that you have collected. Based on the amount of albumin detected, the test strip changes color. The result is only a semi-quantitative value, but it can tell if there is high albumin level in your urine.
- Self-collection kits: This type of test involves obtaining your test sample at home and then sending it to a laboratory for analysis. Almost all 24-hour urine samples require self-collection with special bags or containers provided by your doctor.
Urine albumin-to-creatinine ratio testing is not normally done at home.
There are benefits and drawbacks to each kind of urine albumin testing, so it is important to talk with your doctor about which type of test is most appropriate in your situation and whether it can be performed at home.
How much does the test cost?
The expected cost of a urine test measuring albumin will vary based on multiple factors, including:
- Whether your test uses a dipstick, spot urine sample, or 24-hour urine collection
- Whether any measurements other than albumin are included
- Where the test was performed, including whether you had a point-of-care test
- Whether you have health insurance coverage
The final cost of this testing may be composed of individual charges including office visits, any technical services involved in collecting your sample, and/or laboratory analysis.
When prescribed by a doctor, insurance often covers some or all of the cost of urine albumin testing. Despite this, you may have copayments or out-of-pocket costs toward your deductible.
For the most specific information about likely costs of a urine albumin test, talk with your doctor and health insurance provider.
Taking a Urine Albumin or Albumin-to-Creatinine Ratio Test
There are three main ways to take a urine albumin test: a urine dipstick, a spot urine sample, or a 24-hour urine sample.
Urine dipstick and spot urine tests are one-time samples normally obtained in a medical office, hospital, or lab. The specific albumin-to-creatinine ratio can be determined from a spot urine sample but not a dipstick test.
A 24-hour urine test requires you to collect all the urine you produce for one day, regardless of where you are.
There are important practical considerations for each test, and each has benefits and drawbacks. Your doctor can help you understand which test is recommended for you and provide instructions for taking that version of the test.
Before the test
Before your test, check with your doctor about the schedule and timing of when your urine will be collected. For spot urine samples for albumin-to-creatinine ratio tests, some doctors may prefer to get a sample from early in the morning. If you have a repeat test, they may try to schedule your test for around the same time of day as your previous test to account for normal fluctuations in creatinine production.
Intense exercise can lead to a temporary boost in albumin, so check with your doctor about whether you should restrict vigorous exercise on the day before the test.
You typically do not need to fast before a urine albumin test. Eating meat can affect creatinine levels, though, so your doctor may ask you to avoid it for one day before an albumin-to-creatinine ratio test.
If you are going to do a 24-hour urine test, you should be given special containers before you start your test. Carefully review the test instructions and bring up any questions you have with your doctor or nurse so that you properly prepare your test sample.
During the test
For a urine dipstick test or an albumin-to-creatinine ratio test, you will need to provide a one-time urine sample.
You will take a special container to the bathroom in the doctor’s office or lab to obtain a spot urine sample. Typically, you will be instructed to use the “clean catch” method, which includes urinating in the toilet and then placing the collection cup under your urine stream.
Although not the standard for urine albumin tests, in certain circumstances, your doctor may request a split urine sample, which means that you provide two different spot urine samples at different times during the day. Generally, one sample is done after you’ve been standing or sitting upright, and the other takes place after you have been lying down for several hours.
For a 24-hour urine sample, you will be provided with containers in which you collect all of your urine. On the test day, you urinate into the toilet the first time you urinate after waking up. You then collect all of your urine for the rest of that day and during your first trip to the bathroom after waking up the next day.
After the test
In all three types of tests, you urinate normally, so it is rare to have any side effects after the test is over. After providing a spot or 24-hour urine sample, you can return to all normal daily activities.
Urine Albumin and Albumin-to-Creatinine Ratio Test Results
Receiving test results
If you take a urine dipstick test, results are available within a few minutes. Still, this test does not provide the exact albumin levels. Your doctor can usually discuss the results during the same office visit.
If you take a spot urine test, the albumin-to-creatinine ratio is normally measured by a laboratory, with results available within a few business days. Although rare, in some cases your doctor’s office will have a device that allows for albumin levels to be measured without sending your sample to a lab.
After the lab receives your 24-hour urine sample, the total albumin level will be measured, and results should be available within several business days.
You may get a copy of the test report by mail or an online health portal for urine albumin tests analyzed by a lab. Your doctor may also call or email you to address your test results.
Interpreting test results
The interpretation of your results can depend on the type of urine albumin test that you take as well as your overall health situation and the reason the test was prescribed.
If you have a urine dipstick test, the test strip will change color a few minutes after being in contact with your urine. Based on its color, your doctor or nurse can see whether the test detected high levels of albumin.
For an albumin-to-creatinine ratio test, your result will generally be listed in milligrams of albumin per gram of creatinine (mg/g). And for a 24-hour urine sample, the total milligrams of albumin in the full day’s sample will be shown (mg/day or mg/24 hours).
Albuminuria is the medical term for elevated levels of the protein albumin. In general, the following are considered to be abnormally high amounts of urine albumin:
|CONDITION NAME||FORMER NAME||ALBUMIN-TO-CREATININE LEVEL ON SPOT URINE SAMPLE||TOTAL ALBUMIN LEVEL ON 24-HOUR URINE SAMPLE|
|Moderately Increased Albuminuria
|Microalbuminuria||30 to 300 mg/g (or 3.4 to 34 mg/mmol)||30 to 300 mg/day|
|Severely Increased Albuminuria
|Macroalbuminuria||Over 300 mg/g (or over 34 mg/mmol)||Over 300 mg/day|
It is important to know that neither of these conditions is based on a single test. Instead, a diagnosis of moderately or severely increased albuminuria requires elevated levels on at least two of three tests during a period of three to six months.
Identifying albuminuria is important because it can be a sign of kidney disease. Higher levels of albuminuria are associated with a faster progression of kidney problems. Albuminuria is common in conditions like diabetes and high blood pressure that can have serious negative effects on the kidneys. High urine albumin levels are also considered to be a potential risk factor for cardiovascular problems.
Not all cases of high urine albumin levels are caused by kidney problems. Vigorous exercise, urinary tract infections, fever, and various types of inflammation can lead to temporary rises in albumin levels. Repeat tests are used to diagnose albuminuria in part because of the potential for these types of conditions to influence urine albumin levels.
In general, the less albumin in the urine, the better. Increased amounts of albumin can be tied to a higher risk of cardiovascular problems, even if your levels fall within the normal range.
Talk with your doctor to best understand the results of your urine albumin test. Interpreting the test requires considering your test results along with your overall health, risk factors, and symptoms. Your doctor is in the best position to review these factors and explain what they mean for your health.
To improve your understanding of your urine albumin test, you can bring up some of the following questions when discussing the test result with your doctor:
- Which type of urine albumin test did I have?
- Was my result normal or abnormal?
- How do you interpret my test result? What do you think is the most likely explanation for the test result?
- Should I repeat this test? If so, how often?
- How accurate is the urine albumin test that I had?
- Do you suggest any other tests for follow-up? What are the pros and cons of the different follow-up test options?
A.D.A.M. Medical Encyclopedia. Albumin Blood (Serum) Test. Updated January 24, 2021. Accessed November 29, 2022. https://medlineplus.gov/ency/article/003480.htm.
A.D.A.M. Medical Encyclopedia. Creatinine Blood Test. Updated July 21, 2021. Accessed November 29, 2022. https://medlineplus.gov/ency/article/003475.htm
A.D.A.M. Medical Encyclopedia. Creatinine Clearance Test. Updated July 21, 2021. Accessed November 29, 2022. https://medlineplus.gov/ency/article/003611.htm
A.D.A.M. Medical Encyclopedia. Creatinine Urine Test. Updated July 21, 2021. Accessed November 29, 2022. https://medlineplus.gov/ency/article/003610.htm
A.D.A.M. Medical Encyclopedia. Glomerular Filtration Rate. Updated July 21, 2021. Accessed November 29, 2022. https://medlineplus.gov/ency/article/007305.htm
A.D.A.M. Medical Encyclopedia. Urine 24-hour Volume. Updated July 19, 2021. Accessed November 29, 2022. https://medlineplus.gov/ency/article/003425.htm.
A.D.A.M. Medical Encyclopedia. Urine Protein Dipstick Test. Updated July 19, 2021. Accessed November 29, 2022. https://medlineplus.gov/ency/article/003580.htm
American Board of Internal Medicine. ABIM Laboratory Test Reference Ranges. Updated January 2022. Accessed November 29, 2022. https://www.abim.org/Media/bfijryql/laboratory-reference-ranges.pdf
Bakris GL. Moderately Increased Albuminuria (Microalbuminuria) in Type 2 Diabetes Mellitus. In: Glassock RJ, Nathan DM, eds. UpToDate. Updated September 8, 2021. Accessed November 29, 2022. https://www.uptodate.com/contents/moderately-increased-albuminuria-microalbuminuria-in-type-2-diabetes-mellitus
Gounden V, Bhatt H, Jialal I. Renal Function Tests. In: StatPearls. Updated July 18, 2022. Accessed November 29, 2022. https://www.ncbi.nlm.nih.gov/books/NBK507821/
Haider MZ, Aslam A. Proteinuria. In: StatPearls. Updated April 30, 2022. Accessed November 29, 2022. https://www.ncbi.nlm.nih.gov/books/NBK564390/
Leddy J, Green JA, Yule C, Molecavage J, Coresh J, Chang AR. Improving Proteinuria Screening With Mailed Smartphone Urinalysis Testing in Previously Unscreened Patients With Hypertension: a Randomized Controlled Trial. BMC Nephrol. 2019;20(1):132. Published 2019 Apr 18. doi:10.1186/s12882-019-1324-z
Maddukuri G. Proteinuria. Merck Manual Professional Edition. Updated September 2022. Accessed November 29, 2022. https://www.msdmanuals.com/professional/genitourinary-disorders/symptoms-of-genitourinary-disorders/proteinuria
MedlinePlus: National Library of Medicine. Microalbumin Creatinine Ratio. Updated September 12, 2022. Accessed November 29, 2022. https://medlineplus.gov/lab-tests/microalbumin-creatinine-ratio/
Moman RN, Gupta N, Varacallo M. Physiology, Albumin. In: StatPearls. Updated January 4, 2022. Accessed November 29, 2022. https://www.ncbi.nlm.nih.gov/books/NBK459198/
Nah EH, Cho S, Kim S, Cho HI. Comparison of Urine Albumin-to-Creatinine Ratio (ACR) Between ACR Strip Test and Quantitative Test in Prediabetes and Diabetes. Ann Lab Med. 2017;37(1):28-33. doi:10.3343/alm.2017.37.1.28
National Institute of Diabetes and Digestive and Kidney Diseases. Albuminuria: Albumin in the Urine. Updated October 2016. Accessed November 29, 2022. https://www.niddk.nih.gov/health-information/kidney-disease/chronic-kidney-disease-ckd/tests-diagnosis/albuminuria-albumin-urine
National Institute of Diabetes and Digestive and Kidney Diseases. Assess Urine Albumin. Date unknown. Accessed November 29, 2022. https://www.niddk.nih.gov/health-information/professionals/clinical-tools-patient-management/kidney-disease/identify-manage-patients/evaluate-ckd/assess-urine-albumin
National Institute of Diabetes and Digestive and Kidney Diseases. Laboratory Evaluation of Kidney Disease: Frequently Asked Questions. Date unknown. Accessed November 29, 2022. https://www.niddk.nih.gov/health-information/professionals/clinical-tools-patient-management/kidney-disease/laboratory-evaluation/frequently-asked-questions
National Institute of Diabetes and Digestive and Kidney Diseases. Urine Albumin. Date unknown. Accessed November 29, 2022. https://www.niddk.nih.gov/health-information/professionals/clinical-tools-patient-management/kidney-disease/laboratory-evaluation/urine-albumin
National Kidney Foundation. Using a Home Test Kit and Smartphone to Test for Kidney Disease. Published April 10, 2018. Accessed November 29, 2022. https://www.kidney.org/news/using-home-test-kit-and-smartphone-to-test-kidney-disease
Obrador GT. Epidemiology of Chronic Kidney Disease. In: Curhan GC, Tonelli M, eds. UpToDate. Updated June 24, 2022. Accessed November 29, 2022. https://www.uptodate.com/contents/epidemiology-of-chronic-kidney-disease
Perrone RD, Inker LA. Patient Education: Collection of a 24-hour Urine Specimen (Beyond the Basics). In: Sterns RH, ed. UpToDate. Updated July 13, 2022. Accessed November 29, 2022. https://www.uptodate.com/contents/collection-of-a-24-hour-urine-specimen-beyond-the-basics
Prasad RM, Tikaria R. Microalbuminuria. In: StatPearls. Updated April 30, 2022. Accessed November 29, 2022. https://www.ncbi.nlm.nih.gov/books/NBK563255/
Roberts JR. InFocus: Urine Dipstick Testing Has Limitations, But Is Still Useful in the ED. Emergency Medicine News. December 2020; 42(12):12-14. doi: 10.1097/01.EEM.0000724572.59732.cd
Rovin BH. Assessment of Urinary Protein Excretion and Evaluation of Isolated Non-nephrotic Proteinuria in Adults. In: Glassock RJ, Curhan GC, eds. UpToDate. Updated August 8, 2022. Accessed November 29, 2022. https://www.uptodate.com/contents/assessment-of-urinary-protein-excretion-and-evaluation-of-isolated-non-nephrotic-proteinuria-in-adults
Rovin BH. Patient Education: Protein in the Urine (Proteinuria). In: Glassock RJ, ed. UpToDate. Updated August 16, 2021. Accessed November 29, 2022. https://www.uptodate.com/contents/protein-in-the-urine-proteinuria-beyond-the-basics