McKesson Clinical Reference Systems: Women's Health Advisor 2002.2

What is asymptomatic bacteriuria?

Asymptomatic bacteriuria is a condition in which bacteria are in your urine, but you have no symptoms of infection.

How does it occur?

Urine is normally sterile, which means that it contains no bacteria. A small number of bacteria may be found in the urine of many healthy people. This is usually considered to be harmless. However, a certain level of bacteria can mean that the bladder, urethra, or kidneys are infected.

Anything that blocks the flow of urine or causes incomplete emptying of the bladder provides a place where bacteria can grow in the urine. For example, a stone or tumor might block the flow of urine.

Asymptomatic bacteriuria occurs more often in women than men because a woman's urethra is shorter. The short urethra makes it easier for bacteria from the anus or genital area to reach the bladder. This can happen during such activities as wiping or sexual intercourse. Most infections of the urinary tract are caused this way. Bacteria can also enter the urine through the bloodstream, but this is rare.

Elderly women and pregnant women, particularly pregnant women with diabetes or sickle cell trait, have an increased risk of asymptomatic bacteriuria.

What are the symptoms?

Asymptomatic bacteriuria has no obvious symptoms.

How is it diagnosed?

Your health care provider may examine you and ask you to provide two urine samples about a week apart. The urine samples will be tested for bacteria. You may also have some blood tests.

If you have bacteriuria more than once, you may have:

• more blood tests
• a special x-ray of the kidneys called an intravenous pyelogram (IVP)
• an ultrasound scan.

The IVP and ultrasound scan can show problems in the urinary tract.

How is it treated?

Your health care provider may or may not prescribe an antibiotic. If you are prescribed an antibiotic, take all of it even though you have no symptoms.

You may need to return to your health care provider's office after you have taken all of the antibiotic to have your urine tested again. Your provider may recommend testing your urine regularly to see if the bacteriuria recurs.

In some cases regular urine testing rather than antibiotic treatment may be the best course. Your health care provider will determine what treatment is best for you.

How long will the effects last?

Asymptomatic bacteriuria usually clears up after treatment with antibiotics. However, it can recur.

If asymptomatic bacteriuria is not treated, it could develop into a full-blown urinary tract infection. If the infection is not then treated with antibiotics, the kidneys could be damaged.

How can I take care of myself?

• Take all of the antibiotic your health care provider prescribes, even if you have no symptoms. Do not take medication left over from previous infections.
• Drink six to eight glasses of fluid each day to cleanse the bladder and the rest of the urinary tract.
• Return to your health care provider for a follow-up urine test within 1 week after you finish taking the antibiotic.
• Follow your health care provider's recommendation for regular urine testing to check for recurrence.

What can be done to help prevent asymptomatic bacteriuria?

You can take the following steps to help prevent a bladder infection from recurring:

• Drink plenty of fluids (six to eight glasses each day).
• Urinate regularly during the day and empty your bladder completely each time.
• Keep the vaginal area clean. Wipe from front to back after a bowel movement.
• Urinate before and after intercourse.
• Wear cotton underwear, which allows better air circulation than nylon. Wear pantyhose that have a cotton crotch.
• Avoid tight clothes in the genital area, such as control-top pantyhose and tight jeans. Do not wear a wet bathing suit for long periods of time.
• Use tampons instead of sanitary pads during your menstrual periods. Change tampons every 3 to 4 hours. Sanitary pads can act as a breeding ground for bacteria, which can enter the urethra and the bladder.

If you have a history of recurrent urinary tract problems, your health care provider may prescribe small doses of antibiotics to be taken continually.

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.