Asymptomatic Bacteriuria

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Asymptomatic Bacteriuria

What Is It?

When a significant number of bacteria show up in the urine, this is called "bacteriuria." Finding bacteria in the urine can mean there is an infection somewhere in the urinary tract (the system that passes urine first from the kidneys, through the tube-like ureters, into the bladder and finally out through the urethra). A urinary tract infection can cause several symptoms, from pain or burning during urination to pelvic pain, back pain, fever and chills.

In asymptomatic bacteriuria, large numbers of bacteria are present in the urine, but a person has no symptoms of a urinary tract infection (asymptomatic means without symptoms). It is not clear why the bacteria don't cause symptoms. It may be that asymptomatic bacteriuria is caused by weaker (less "virulent") bacteria. The condition does not always need to be treated.

Asymptomatic bacteriuria is most common in women, people with diabetes, the elderly and those with bladder catheters.

Symptoms

Asymptomatic bacteriuria does not cause any symptoms.

Diagnosis

Your doctor will determine that you have asymptomatic bacteriuria based on laboratory testing of your urine that shows at least 100,000 bacteria per milliliter of urine. A person must take care when collecting a urine sample because bacteria from the skin can contaminate the sample. To decide if you do or do not have any symptoms of a urinary tract infection, your doctor may ask you detailed questions about your urine, including questions about its color, odor and whether you have noticed any blood in your urine. He or she also may ask about the number of times you urinate during the day and at night, and whether you have had any episodes of bedwetting, pain during urination, an urgent need to urinate, pelvic pain, back pain, fever or chills.

Your doctor may ask you to give additional urine samples to confirm the presence of the same type of bacteria. These samples may be sent for testing to identify the specific type of bacteria and to identify specific antibiotics that can be used to eliminate the bacteria.

Expected Duration

In some people, asymptomatic bacteriuria eventually progresses to a full-blown urinary tract infection, with the usual symptoms. In other people, asymptomatic bacteriuria can continue for days or years without causing obvious illness or discomfort.

Prevention

You may help prevent bacteriuria by drinking several glasses of water each day. This may discourage the growth of bacteria by flushing out your urinary tract, although this has not been proven. Drinking cranberry juice every day might also slow the growth of bacteria by making your urine more acidic, but this also has not been definitively shown through medical studies.

To prevent the spread of intestinal bacteria from the rectum to the urinary tract, women should always wipe toilet tissue from front to back after having a bowel movement.

Treatment

Antibiotic treatment for asymptomatic bacteriuria is recommended for the following groups:

• Pregnant women

• People about to undergo surgery in any part of the urinary tract

• Men about to undergo prostate surgery

• People who have had a kidney transplant

• People with obstruction or abnormal structure of the urinary tract

Most people with asymptomatic bacteriuria are elderly women, a group that does not require treatment for this condition. Although antibiotic treatment can clear the bacteria from the urine, the condition often returns. Your doctor may wait until the results of at least two urine cultures have confirmed the presence of the same bacteria before beginning treatment. At that point, your doctor will have been able to identify the type of bacteria and determine the most effective antibiotic to treat it. People with bladder catheters and asymptomatic bacteriuria must be monitored closely for the development of symptoms.

When To Call a Professional

If you have asymptomatic bacteriuria, call your doctor immediately if you begin urinating more often than normal; develop an intense need to urinate; have pain during urination; or if your urine has blood in it, becomes discolored, cloudy or foul smelling, or if you develop pelvic pain, back pain, fevers or chills.

Prognosis

For most people, asymptomatic bacteriuria does not cause any problems and treatment is not necessary.

Additional Info

National Kidney Foundation 30 East 33rd St. New York, NY 10016 Phone: 212-889-2210 Toll-Free: 1-800-622-9010 http://www.kidney.org/

American Urological Association 1000 Corporate Blvd. Linthicum, MD 21090 Phone: 410-689-3700 Toll-Free: 1-866-746-4282 Fax: 410-689-3800 http://www.urologyhealth.org/

Last updated:	January 08, 2009