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Asymptomatic Bacteriuria (Bacteria in Urine, No Symptoms)

What is asymptomatic bacteriuria?

Asymptomatic bacteriuria means you have bacteria in your urine but you have no symptoms of infection. If you are healthy, this condition is usually not a problem.

Bacteria in your urine can cause a more serious kidney infection if you are pregnant, have had a kidney transplant, have diabetes, have kidney stones, or are going to have surgery on the urinary tract (including the prostate). Older people and people who have a medical condition that lowers their ability to fight infections may also be at risk for more serious infections if they have bacteria in their urine.

What is the cause?

The urinary tract includes your:

  • Kidneys, which make urine
  • Ureters, which are the tubes that carry urine from the kidneys to the bladder
  • Bladder, which stores urine
  • Urethra, which is the tube that drains urine from the bladder

Normally there should be no bacteria in the urinary tract. However, bacteria can spread from the rectum or vagina to the urethra and then up into the bladder.

Bacteria in the urine is more common in women because the urethra is short. The short urethra makes it easier for bacteria from the rectum or the genital area to reach the bladder. This can happen during sex. Young women often have bladder infections when they have just started having sex. Irritation and dryness of the vagina after menopause may increase the risk for bladder infections.

Bacteria may grow in the urine if the flow of urine is blocked. For example, when a woman is pregnant, pressure from the baby can cause this problem. In men, an enlarged prostate may cause a blockage. Kidney stones can also cause blockage and infections.

Bacteria can also enter the urine through the bloodstream, but this is rare.

What are the symptoms?

Asymptomatic bacteriuria has no symptoms.

How is it diagnosed?

If you are pregnant, have had a kidney transplant, have diabetes, have kidney stones, or are about to have surgery on the urinary tract, you may have routine urine tests to check for bacteria in your urine.

If you have bacteria in your urine, you may have:

  • Blood tests
  • An intravenous pyelogram (IVP), which is a series of X-rays taken after your healthcare provider injects dye into your blood vessels to look for blockages in your kidneys and urinary tract
  • An ultrasound, which uses sound waves to show pictures of the kidneys and urinary tract

How is it treated?

If you are healthy, asymptomatic bacteriuria is usually not a problem and does not need treatment. If you have had urinary tract infections in the past, your healthcare provider may prescribe medicine for you to take to help prevent a more serious infection

Your healthcare provider may prescribe an antibiotic if:

  • You are pregnant. (Infection could cause a low-birth-weight baby or it may cause you to go into labor too early.)
  • You are going to have tests or surgery on your urinary tract.
  • You have a blockage of your urinary tract, such as a kidney stone.
  • You have a medical condition such as diabetes that lowers your ability to fight infections.

If you are treated with an antibiotic, you may need to have your urine tested again after you have taken all of the medicine. Your provider may recommend follow-up tests of your urine to see if the problem comes back.

How can I take care of myself?

  • Drink plenty of water each day to flush your bladder and urinary tract unless your healthcare provider has told you to limit how much liquid you drink.
  • Follow the full course of treatment prescribed by your healthcare provider. If you were prescribed an antibiotic, take all of it as prescribed, even if you have no symptoms. Ask your provider:
    • How and when you will hear your test results
    • What activities you should avoid and when you can return to your normal activities
    • How to take care of yourself at home
    • What symptoms or problems you should watch for and what to do if you have them
  • Make sure you know when you should come back for a checkup.

How can I help prevent asymptomatic bacteriuria?

You may help prevent bladder infection if you:

  • Drink enough liquids to keep urine light yellow in color.
  • Drink a glass of cranberry juice each day. The juice should be real cranberry juice, not a cranberry-flavored drink.
  • Don’t wait to go to the bathroom if you feel the need to urinate.
  • Urinate soon after sex.
  • Keep your genital area clean. If you want to have vaginal sex after anal sex, both partners should wash their genitals first.
  • Empty your bladder completely when you urinate.
  • Don’t wear a wet bathing suit for long periods of time.

Also, if you are a woman:

  • Don’t use irritating cosmetics or chemicals in your genital area. This includes, for example, strong soaps, feminine hygiene sprays, douches, scented tampons, sanitary napkins, or panty liners.
  • Keep your vaginal area clean. Wiping from front to back after using the toilet may help prevent infections. Use mild, unscented soap to wash your genital area gently each time you bathe or shower.
  • Wear underwear that is all cotton or has a cotton crotch. Pantyhose should also have a cotton crotch. Cotton keeps your body cooler than nylon. Change underwear and pantyhose every day.
  • During pregnancy, tell your healthcare provider if you have had urinary tract problems in the past.
  • If you have reached menopause and are not taking estrogen, prescription vaginal cream may help prevent bladder infections.

Men should always wash their penis during baths or showers. Men who are not circumcised should gently pull back the foreskin and wash the tip of the penis when they take a bath or shower.

Developed by RelayHealth.
Adult Advisor 2015.1 published by RelayHealth.
Last modified: 2014-10-30
Last reviewed: 2014-10-30
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright ©1986-2015 McKesson Corporation and/or one of its subsidiaries. All rights reserved.

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