Most of the time, your urine is sterile. This means there are no bacteria growing. On the other hand, if you have symptoms of a bladder or kidney infection, bacteria will often be present and growing in your urine.

Sometimes, your health care provider may check your urine for bacteria, even when you do not have any symptoms. If enough bacteria are found in your urine, you have asymptomatic bacteriuria.

Screening - asymptomatic bacteria

Asymptomatic bacteriuria occurs in a small number of healthy people. It affects women more often than men. The reasons for the lack of symptoms are not well understood.

You are more likely to have this problem if you:

• Have a urinary catheter in place
• Are female
• Are pregnant
• Are sexually active (in females)
• Have long-term diabetes and are female
• Are an older adult
• Have recently had a surgical procedure in your urinary tract

There are no symptoms of this problem.

If you have these symptoms, you may have a urinary tract infection, but you do not have asymptomatic bacteriuria.

• Burning during urination
• Increased urgency to urinate
• Increased frequency of urination

Most people who have bacteria growing in their urine, but no symptoms, do not need treatment. This is because the bacteria are not causing any harm. In fact, treating most people with this problem may make it harder to treat infections in the future.

However, for some people getting a urinary tract infection is more likely or may cause more severe problems. As a result, treatment with antibiotics may be needed if:

• You are pregnant.
• You recently had a kidney transplant.
• You are scheduled for surgery involving the prostate gland or the bladder.
• You have kidney stones that have caused an infection.
• Your young child has reflux (backward movement of urine from the bladder into ureters or kidneys).

Without symptoms being present, even people who are older adults, have diabetes, or have a catheter in place do not need treatment.

If it is not treated, you may have a kidney infection if you are at high risk.

Contact your provider if you have:

• Difficulty emptying your bladder
• Fever
• Flank or back pain
• Pain with urination

You will need to be checked for a bladder or kidney infection.

Published Date: August 15, 2022
Published By: Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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Smaill FM, Vazquez JC. Antibiotics for asymptomatic bacteriuria in pregnancy. Cochrane Database Syst Rev. 2019;11:CD000490. PMID: 31765489 pubmed.ncbi.nlm.nih.gov/31765489/.

Zalmanovici Trestioreanu A, Lador A, Sauerbrun-Cutler M-T, Leibovici L. Antibiotics for asymptomatic bacteriuria. Cochrane Database Syst Rev. 2015;4:CD009534. PMID: 25851268 pubmed.ncbi.nlm.nih.gov/25851268/.