Albumin Urine Test
Test OverviewAn albumin test
checks urine for a protein called
albumin. Albumin is normally found in the blood and
filtered by the
kidneys. When the
kidneys are working as they should, there may be a very small amount of albumin in the urine. But when the kidneys are damaged, abnormal amounts of albumin leak
into the urine. This is called albuminuria. If the amount of albumin is very small, but still abnormal, it is called microalbuminuria. Albuminuria is most often caused by kidney damage from
diabetes. But many other conditions can lead to kidney
damage. These include high blood pressure,
heart failure,
cirrhosis, and
lupus. If early kidney
damage is not treated, larger amounts of albumin may leak into the
urine. When the
kidneys spill albumin, it can mean serious kidney damage is present. This can
lead to
chronic kidney disease. An albumin urine test can
be done on a sample of urine that is collected: - At a random time. This is usually after the first time
you urinate in the morning.
- Over a 24-hour period.
- Over a specific period of time, such as 4 hours or
overnight.
Why It Is DoneThis test is done to
check for albumin in the urine. Finding it early may change treatment so a person will keep as much kidney function as possible. Sometimes an albumin-creatinine ratio test is also done. This urine test compares the amount of albumin with the amount of a waste product called creatinine (say "kree-AT-uh-neen"). The test can help give a more accurate measure of albumin levels. This is because the amount of albumin can change, depending on how much water is in your urine. But creatinine levels tend to stay the same. How To PrepareYou do not need to do anything special to prepare for this test. How It Is DoneFor a random urine test, you will
provide a clean-catch midstream urine sample. A morning urine sample gives the
best information about albumin levels. Clean-catch midstream one-time urine collection- Wash your hands to make sure they are clean
before you collect the urine.
- If the collection cup has a lid,
remove it carefully. Set it down with the inner surface up. Do not touch the
inside of the cup with your fingers.
- Clean the area around your
genitals.
- For men: Pull back the foreskin, if
you have one. Clean the head of the penis thoroughly with medicated towelettes
or swabs.
- For women: Spread open the folds of skin around the
vagina with one hand. Then use your other hand to clean
the area around the vagina and
urethra thoroughly with medicated towelettes or swabs.
Wipe the area from front to back to avoid spreading bacteria from the
anus to the urethra.
- Start urinating into the toilet or urinal. Women should keep holding apart the folds of skin around the vagina while
they urinate.
- After the urine has flowed for several seconds, place
the collection cup into the stream. Collect about
2 fl oz (60 mL) of this
"midstream" urine without stopping the flow.
- Do not touch the
rim of the cup to your genital area. And don't get toilet paper, pubic hair,
stool (feces), menstrual blood, or other foreign matter in the urine
sample.
- Finish urinating into the toilet or
urinal.
- Carefully replace the lid on the cup. Return the cup to the
lab. If you are collecting the urine at home and can't get it to the lab in an
hour, refrigerate it.
A urine sample collected over time, such as over 4 or
24 hours, gives the most accurate results. So you may be asked to collect your
urine over a specific time period. Timed urine collection (24 hours)- You start collecting your urine in the morning. When you first
get up, empty your bladder but do not save this urine. Write down the time that
you urinated. This marks the beginning of your 24-hour collection
period.
- For the next 24 hours, collect all your urine. Your doctor
or lab will usually provide you with a large container that holds about
1 gal (4 L). The container has
a small amount of preservative in it. Urinate into a small, clean container, and
then pour the urine into the large container. Do not touch the inside of either
container with your fingers.
- Keep the large container in the
refrigerator for the 24 hours.
- Empty your bladder for the final
time at or just before the end of the 24-hour period. Add this urine to the
large container, and record the time.
- Do not get toilet paper, pubic
hair, stool (feces), menstrual blood, or other foreign matter in the urine
sample.
How It FeelsThis test does not cause any pain. RisksCollecting a urine sample does not cause problems. ResultsAn albumin test checks urine for the
presence of a protein called
albumin. This is called albuminuria. It is most often caused by
kidney damage from
diabetes. But many other conditions can lead to kidney
damage. These numbers are just a guide. The range for "normal" varies from lab to lab. Your lab may have a different range. Your lab report should show what range your lab uses for "normal." Also, your doctor will evaluate your results based on your health and other factors. So a number that is outside the normal range here may still be normal for you. Higher-than-normal values You may need more than
one test to find out how well your kidneys are working. - If your results are higher than normal, your doctor may check
your urine more often to watch for kidney damage.
- If you have 2 or 3 high results in a 3- to 6-month period and
you have diabetes, your doctor may find kidney damage (diabetic nephropathy). Even though diabetes is the most common reason for high
results, there are many other kidney problems that can cause high
results.
Pregnant women with diabetes may have their urine checked
to watch for high amounts of albumin. What Affects the TestYou may not be able to have the test, or the results may not be helpful, if: - You have a urinary tract infection, high blood pressure,
heart failure, or a high fever during an
infection.
- You exercise just before the test.
- You take medicines such as aspirin,
corticosteroids, or some
antibiotics, such as amoxicillin.
- You have menstrual bleeding or vaginal discharge. These may temporarily affect the urine sample.
What To Think About- The American Diabetes Association recommends three tests to check for kidney damage. These tests are blood pressure, urine albumin, and a creatinine blood test to calculate an estimated glomerular filtration rate (eGFR). Creatinine is a waste product that is filtered out of the blood by healthy kidneys. To learn more, see the topic
Creatinine and Creatinine Clearance.
- If you have type 2 diabetes, you should have
these tests when you are first diagnosed. Then have them each year to check for diabetic nephropathy.
- If you
have type 1 diabetes, you should have these tests to check for diabetic nephropathy each year, starting 5 years after
diagnosis.
- If you have either type of diabetes and are pregnant,
talk to your doctor about how often you need to be tested.
- The urine dipstick test can be used to check for
albumin in a single sample of urine. But the dipstick test is not as accurate a test for finding albuminuria as the urine test. It is not recommended in place of an albumin urine test.
ReferencesCitations- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.
- Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
Other Works Consulted- American Diabetes Association (2017). Standards of medical care in diabetes-2017. Diabetes Care, 40(Suppl 1): S1-S135. http://care.diabetesjournals.org/content/40/Supplement_1. Accessed December 15, 2016.
- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.
- Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
CreditsByHealthwise Staff Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine Kathleen Romito, MD - Family Medicine Adam Husney, MD - Family Medicine Specialist Medical ReviewerCaroline S. Rhoads, MD - Internal Medicine Current as of:
May 3, 2017 Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier. Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders. Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins. Last modified on: 8 September 2017
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