What Is a Microalbuminuria Test?

    The kidneys are responsible for removing waste products from the blood and regulating the water fluid levels. When damage to the kidneys occurs, this pair of organs may fail to filter out wastes. Additionally, damaged kidneys may fail to retain nutrients and proteins from the body that are essential to health. Such is the case with albumin.

    Albumin is a protein that is used by the body for normal cell growth and tissue repair. If the kidneys become damaged, they may not retain this protein within bloodstream causing it to be excreted with the urine. When this occurs you may experience serious health complications. Maintaining normal kidney function is vital to ensuring that albumin remains in the bloodstream.

    The microalbuminuria test is a urine test that measures the amount of albumin in your urine. If kidney damage has occurred, albumin will leak into the bloodstream and will be present in the urine. The microalbuminuria test is also known as:

    • the ACR test
    • the albumin-to-creatinine ratio test
    • the urine albumin test

    What Is the Purpose of the Test?

    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 should be removed by the kidneys. When kidney damage occurs, creatinine levels in the urine decrease while albumin levels may increase.

    Measuring the amount of albumin in the urine is important for detecting the presence of kidney damage. Kidney damage can lead to kidney failure, requiring the patient to undergo dialysis. By identifying kidney damage before it results in kidney failure, your doctor can slow the progression of the disease to preserve kidney function over the long term.

    When Is the Test Ordered?

    An annual microalbuminuria test is recommended for all individuals 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. This damage can be detected through the use of the microalbuminuria test. Positive test results in patients with diabetes should be confirmed through additional testing over a three- to six-month period. If kidney damage is confirmed, your doctor will be able to treat this disease and help improve and maintain kidney function.

    Patients with hypertension may also be screened for kidney damage through the microalbuminuria test. Hypertension 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 this test needs to be administered.

    Preparation for the Test

    No special preparation is needed for the test.

    How Is the Test Administered?

    There are two types of microalbuminuria tests. The first can be administered in any healthcare setting. It requires you to provide a urine sample. The sample is collected in a sterile cup and sent to a laboratory for analysis. Once the lab reports the results, your doctor will be able to provide you with more information about the results and what they mean.

    The second microalbuminuria test involves the collection of a 24-hour urine sample. To complete this test, you will be required to collect all of your urine for a 24-hour period. Your doctor will provide you with a container for urine collection that must be kept in the refrigerator. Once you have collected your urine for 24 hours, you will need to return the sample to your healthcare provider for laboratory analysis. Your doctor will be able to explain the results to you after the analysis is complete.

    What Are the Risks of the Test?

    The microalbuminuria test only requires normal urination. Therefore, there are no risks and there should be no discomfort.

    Understanding Your Results

    The results of the microalbuminuria test will vary, depending on the laboratory where the sample was analyzed. Normal values are typically less than 30 mcg/mg (micrograms per milligram). A low level of albumin in the urine is an indication that your kidneys are functioning normally.

    If an abnormal result is reported, your doctor will have you complete the microalbuminuria test again to confirm the results. Dehydration and high levels of exercise may increase albumin levels in the urine. As such, the results must be confirmed through additional testing. Based on the results from the microalbuminuria test, your doctor will be able to determine the extent of the kidney damage that has occurred. The results will also enable your doctor to provide appropriate treatment for kidney damage and its underlying cause.