What is a microalbuminuria test?
If your doctor believes you may be at risk for kidney damage or kidney
disease, it’s likely that you’ve had or will have a microalbuminuria test. The microalbuminuria test is a
urine test that measures the amount of albumin in your urine. Albumin is a
protein that your body uses for cell growth and to help repair tissues. It’s normally
present in the blood. A certain level of it in your urine may be a sign of
Your kidneys are responsible for removing waste products from the blood and
regulating the water fluid levels in your body. Healthy kidneys make sure that
waste is filtered out from your body and that nutrients and proteins that are
essential to your health, such as albumin, stay in your body.
It’s important to make sure your kidneys are functioning properly so that
albumin remains in your blood. If your kidneys have been damaged, they may not
be able to keep albumin in your blood and it will start to spill into your
urine. When this occurs, you may experience a condition known as albuminuria. Albuminuria
simply means that your urine contains albumin.
The microalbuminuria test is also known as the albumin-to-creatinine ratio (ACR) test or the urine
What is the purpose of the test?
Your doctor may recommend a microalbuminuria test if you’re
at risk for kidney damage or if they suspect your kidneys might be damaged. It’s
important for your doctor to test and diagnose you as early as possible if your
kidneys are damaged. Treatment may delay or prevent kidney disease. The two
most common causes of kidney disease in the United States are diabetes and
hypertension, or high blood pressure. Your doctor may order the microalbuminuria
test if you have one of these conditions.
The purpose of the microalbuminuria test is to measure the amount of albumin
in the urine. The test is typically used in conjunction with a creatinine test
to provide an albumin-to-creatinine ratio. Creatinine is a waste product in the
blood that your kidneys should remove. When kidney damage occurs, creatinine
levels in the urine decrease while albumin levels may increase.
How often you need microalbuminuria tests
depends on whether you have any underlying conditions or whether you have the
symptoms of kidney damage. Early stages of kidney damage usually show no signs
or symptoms. However, if kidney damage is extensive, your urine may appear
foamy. You may also experience swelling, or edema, in your:
The American Diabetes Association recommends an annual microalbuminuria test
for people between the ages of 12 and 70 that have been diagnosed with type 1
or type 2 diabetes. Diabetes can cause damage to the kidneys. Your doctor can
use a microalbuminuria test to detect this damage. If you have positive test
results and you have diabetes, your doctor should confirm the results through
additional testing over a three- to six-month period. If they confirm you have
kidney damage, your doctor will be able to treat the kidney injury and help
improve and maintain your kidney function.
High blood pressure
If you have high blood pressure, your doctor may also screen you for kidney
damage using the microalbuminuria test. High blood pressure can cause damage to
the vessels of the kidney, resulting in the release of albumin into the urine.
Testing for albumin should occur at regular intervals. Your doctor will
determine when you need this test.
Preparation for the test
The microalbuminuria test is a simple urine test. You can eat and drink
normally before the test. No special preparation is necessary for this test.
How is the test administered?
Several types of microalbuminuria urine tests are available:
Random urine test
You can take a random urine test at any time. Doctors often combine it with
a creatinine test to improve the accuracy of the results. You can have this
test in any healthcare setting. You’ll collect the sample in a sterile cup, and
your doctor will send it to a laboratory for analysis.
24-hour urine test
For this test, you’ll need to collect all of your urine for a 24-hour period.
Your doctor will provide you with a container for urine collection that you must
keep in the refrigerator. Once you’ve collected your urine for 24 hours, you’ll
need to return the sample to your healthcare provider for lab analysis.
Timed urine test
Your doctor may ask you to provide a urine sample first thing in the morning
or after a four-hour period of not urinating.
Once the lab reports the results, your doctor will be able to provide you
with more information about the results and what they mean.
What are the risks of the test?
The microalbuminuria test only requires normal urination. This test has no
risks, and you shouldn’t have any discomfort.
Understanding your results
to the National
Kidney Foundation, albuminuria is the presence of too much albumin in the
urine. Microalbuminuria is the presence of a slightly high level of protein in
the urine, and macroalbuminuria is the presence of a very high level of albumin
in the urine each day. Results of the microalbuminuria test are measured as
milligrams (mg) of protein leakage in your urine over 24 hours. Results
generally indicate the following:
- Less than 30 mg of
protein is normal.
- Thirty to 300 mg of
protein is known as microalbuminuria, and it may indicate early kidney
- More than 300 mg of
protein is known as macroalbuminuria, and it indicates more advanced
Several temporary factors can cause higher-than-normal urinary microalbumin
results, such as:
- blood in your urine, or
- a fever
- recent vigorous exercise
- a urinary tract infection
medications can also affect albumin levels in your urine. Examples include:
- antibiotics, including aminoglycosides,
B, and sulfonamides
- antifungal medications, including amphotericin B
- lithium, which is a medication people use
to treat the manic episodes of bipolar disorder
- penicillamine, which is a medication people
use to treat rheumatoid arthritis
- phenazopyridine, which is a medication
people use to treat urinary tract pain
- salicylates, which are medications people use to
- tolbutamide, which is a medication people
use to treat diabetes
your results have been processed, your doctor will call you and may want
to test your urine again if the first test has abnormal results. If necessary,
your doctor will recommend the best treatment options for your kidney damage
and its underlying cause.
Measuring the amount of albumin in your urine is important for detecting the
presence of kidney damage. Kidney damage can lead to kidney disease or failure.
If kidney failure occurs, dialysis is often necessary. By identifying kidney
damage before it results in kidney failure, your doctor can slow the
progression of any further damage and help preserve your kidney function over
the long term.