Uric Acid in Urine
The uric acid urine test measures the amount
uric acid in a sample of urine collected over 24
hours. Uric acid is produced from the natural breakdown of your body's cells
and from the foods you eat.
Most of the uric acid is removed from
the body in urine. A small amount passes out of the body in stool. But if too
much uric acid is being produced, the level in the urine will increase. If the
kidneys are not able to remove it from the blood normally, the level of uric
acid in the urine will decrease.
High blood levels of uric acid in
the body can cause solid crystals to form within joints. This causes a painful
gout. If gout remains untreated, uric acid crystals
can build up in the joints and nearby tissues, forming hard lumpy deposits
tophi. High levels of uric acid in the urine can cause
Why It Is Done
A uric acid urine test is done
- Check to see if kidney stones may be caused by
high uric acid levels in the body.
- Find the cause of a high level
of uric acid in the blood and help choose the proper treatment.
How To Prepare
No special preparation is required
before having a uric acid urine test. It is not necessary to restrict fluids or
foods before the test. Be sure to drink enough fluids during the 24-hour urine
test to prevent
During the collection
period, do not drink alcohol, because alcohol reduces the amount of uric acid
eliminated by the kidneys.
Many medicines can change the results
of this test. Be sure to tell your doctor about all the nonprescription and
prescription medicines you take.
Talk to your doctor about any
concerns you have regarding the need for the test, its risks, how it will be
done, or what the results may mean. To help you understand the importance
of this test, fill out the
medical test information form(What is a PDF document?).
How It Is Done
A uric acid urine test is usually done
on a sample taken from all the urine produced in a 24-hour period.
To collect your urine for 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 to mark the beginning of your 24-hour
- For the next 24 hours, collect all your urine.
Your doctor's office 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 the 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.