How Do You Test for Nitrites in Urine?
UTIs are caused by different types of bacteria. Many of these types of bacteria change a normal chemical in your urine, called nitrates, into another chemical, called nitrites. So, if you have nitrites in your urine, it usually means that you have a urinary tract infection (UTI).
UTIs are one of the most common types of infections, especially in women. Most UTIs affect the bladder and urethra (the tube that carries urine out of your body). Fortunately, most UTIs are not serious. They are usually treated with antibiotics. UTIs that aren't treated could spread to the kidneys, which can be serious. So, it's important to diagnose and treat UTIs early.
Other names: urine test, urine analysis, microscopic urine analysis, microscopic examination of urine, UA
What is it used for?
A urinalysis, which includes a test for nitrites in urine, is used to check your general health, including the health of your urinary tract and kidneys. It may also be used to check for a UTI.
Why do I need a nitrites in urine test?
Your provider may order a urinalysis as part of a routine checkup or if you have symptoms of a UTI. Symptoms of a UTI may include:
- Frequent urges to urinate, even when you have little urine in your bladder
- Pain or burning when you urinate
- Dark, cloudy, or reddish colored urine
- Bad smelling urine
- Weakness, fatigue, or confusion, mainly in older people
- Fever, which may be a sign of a kidney infection
If you have symptoms of a UTI, it's important to see your provider so you can start treatment right away, if needed.
What happens during a nitrites in urine test?
You will need to give a urine sample for the test. A health care professional may give you a cleansing wipe, a small container, and instructions for how to use the "clean catch" method to collect your urine sample. It's important to follow these instructions so that germs from your skin don't get into the sample:
- Wash your hands with soap and water and dry them.
- Open the container being careful not to touch the inside.
- Clean your genital area with the cleansing wipe:
- For a penis, wipe the entire head (end) of the penis. If you have a foreskin, pull it back first.
- For a vagina, the labia (the folds of skin around the vagina) should be separated and wiped from front to back on the inner sides.
- Urinate into the toilet for a few seconds, then stop the flow. Start urinating again, this time into the container. Don't let the container touch your body.
- Collect at least an ounce or two of urine into the container. The container should have markings to show how much urine is needed.
- Finish urinating into the toilet.
- Put the cap on the and return it as instructed.
If you have hemorrhoids that bleed or are having your menstrual period, tell your provider before your test.
Will I need to do anything to prepare for the test?
You don't need any special preparations to test for nitrites in urine. If your health care provider has ordered other urine or blood tests, you may need to fast (not eat or drink) for several hours before the test. Your provider will let you know if there are any special instructions to follow.
Are there any risks to the test?
There is no known risk to having a urinalysis or a nitrites in urine test.
What do the results mean?
If there are nitrites in your urine, it may mean that you have a UTI. But, even if no nitrites are found, you may still have an infection. That's because some types of bacteria don't change nitrates into nitrites.
Your provider will also look at other results of your urinalysis, especially tests that look for signs of white blood cells in your urine. White blood cells in urine may also mean you have a UTI. To learn what your results mean, talk with your provider.
Learn more about laboratory tests, reference ranges, and understanding results.
Is there anything else I need to know about a nitrites in urine test?
At-home test kits for UTIs are available without a prescription. These test kits are also called urine dipstick tests or UTI test strips. They check for nitrites and white blood cells in your urine.
At-home UTI tests are quick and easy to use, but they don't always provide accurate results. Your results may say you don't have a UTI when you really do. So, you may still need to see your provider for a nitrites in urine test. If you think you have a UTI, ask your provider which test is right for you.
If you have signs of a UTI, your provider may order a urine culture test to see how much and what type of bacteria may be in your urine. This information helps your provider decide which type of antibiotic medicine to prescribe. In a urine culture test, bacteria from your urine are grown in a lab. Results usually take a couple of days.
If a urinalysis is part of your regular checkup, your urine will be tested for several other substances. These include blood, proteins, acid and sugar levels, cell fragments, and crystals in your urine.
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