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Urinary tract infection - adults

Contents of this page:


Bladder catheterization, female
Bladder catheterization, female
Bladder catheterization, male
Bladder catheterization, male
Female urinary tract
Female urinary tract
Male urinary tract
Male urinary tract
Prevention of cystitis
Prevention of cystitis

Alternative Names    Return to top

Bladder infection - adults; UTI - adults

Definition    Return to top

A urinary tract infection, or UTI, is an infection that can happen anywhere along the urinary tract. The urinary tract includes the:

See also:

Causes    Return to top

Urinary tract infections (UTIs) have different names, depending on where the infection is located.

Cystits, a common condition, is an infection of the bladder. It is usually caused by bacteria entering the urethra and then the bladder. This leads to inflammation and infection in the lower urinary tract.

Pyelonephritis is an infection of one or both kidneys and the surrounding area.

Certain people are more likely to get UTIs. Women tend to get them more often because their urethra is shorter and closer to the anus. Persons with diabetes and very old adults (especially those in nursing homes) are more likely to develop UTIs. The elderly are at increased risk for such infections because the bladder doesn't empty fully due to certain prostate and bladder conditions.

Children can also develop UTIs.

See: Urinary tract infection - children

The following increase your chances of developing a UTI:

Symptoms    Return to top

The symptoms of a bladder infection include:

If the infection spreads to the kidneys, symptoms may include:

For more information see: Pyelonephritis

Exams and Tests    Return to top

A urine sample is usually collected. Urinalysis commonly shows white blood cells, red blood cells, and nitrates in the urine.

See also: RBC - urine

Special urine tests (urine culture (clean catch) or catheterized urine specimen) may be done to determine the type of bacteria in the urine and the appropriate antibiotic for treatment.

Treatment    Return to top


A mild urinary tract infection may go away on its own without treatment. However, antibiotics are usually recommended because there is a risk that the infection can spread to the kidneys. Antibiotics are taken by mouth, usually from 3 to 7 days. It is important that you finish all the medication.

Commonly used antibiotics include:

Your doctor may also recommend drugs to relieve the burning pain and urgent need to urinate, and to decrease bacteria in your urine.

Such medicines include:


If you are very sick and cannot take medicines by mouth or drink enough fluids, you may be admitted to the hospital. You may also be admitted to the hospital if you:

At the hospital, you will receive fluids and antibiotics through a vein.


Some people have urinary tract infections that keep coming back or that do not go away with treatment. Such infections are called chronic UTIs. If you have a chronic UTI, you may need antibiotics for a long period of time, perhaps as long as 6 months to 2 years, or stronger antibiotics may be prescribed.

A urinary tract infection is considered chronic if any of the following occur:

Your health care provider may also recommend low-dose antibiotics after acute symptoms go away.


If a structural (anatomical) problem is causing the infection, surgery may be recommended.

Outlook (Prognosis)    Return to top

A urinary tract infection is uncomfortable, but treatment is usually successful. Symptoms of a bladder infection usually disappear within 24 - 48 hours after treatment begins. If you have a kidney infection, it may take 1 week or longer for your symptoms to go away.

Possible Complications    Return to top

When to Contact a Medical Professional    Return to top

Contact your health care provider if you have symptoms of a UTI. Call right away if the following symptoms develop:

These may be signs of a possible kidney infection.

Also call if you have already been diagnosed with a UTI and the symptoms come back shortly after treatment with antibiotics.

Prevention    Return to top

Lifestyle changes may help prevent some UTIs.




References    Return to top

Cincinnati Children's Hospital Medical Center. Evidence-based care guideline for medical management of first urinary tract infection in children 12 years of age or less. Cincinnati (OH): Cincinnati Children's Hospital Medical Center; 2006 Nov. 23 p.

Lin K, Fajardo K; U.S. Preventive Services Task Force. Screening for asymptomatic bacteriuria in adults: evidence for the U.S. Preventive Services Task Force reaffirmation recommendation statement. Ann Intern Med. 2008 Jul 1;149(1):W20-4.

Norrby SR. Approach to the patient with urinary tract infection. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap.306

Foster RT Sr. Uncomplicated urinary tract infections in women. Obstet Gynecol Clin North Am. 2008 Jun;35(2):235-48, viii.

Pohl A. Modes of administration of antibiotics for symptomatic severe urinary tract infections. Cochrane Database Syst Rev. 2007 Oct 17;(4):CD003237.

Nicolle LE. Uncomplicated urinary tract infection in adults including uncomplicated pyelonephritis. Urologic Clinics of North America. 2008 Feb:35(1).

Update Date: 10/2/2008

Updated by: Louis S. Liou, MD, PhD, Assistant Professor of Urology, Department of Surgery, Boston University School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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