Urinary Tract Infection

A urinary tract infection, or UTI, is an inflammation of the bladder or the bladder and the kidneys. It's usually caused by bacteria from the skin outside the urethra (the tube that carries urine from the bladder outside the body) that move up the urethra and into the bladder. If the bacteria stay in the bladder, the infection is called cystitis. If the bacteria are in the kidneys, it's called pyelonephritis. These infections are not contagious.

UTIs are a common problem in children, but being common doesn't make them any less serious. Left untreated, they can lead to permanent kidney damage and even life-threatening conditions. Because children's kidneys are still developing, they're more vulnerable to damage and scarring from urinary tract infections.

UTIs are more common in newborn boys than girls, but among older children, UTIs are far more common in girls. They're a major cause of hospitalization in children.

Our staff has extensive experience in managing UTIs in children. As an academic medical center, we also have access to the most advanced technology for diagnosing your child's condition.

The signs and symptoms of urinary tract infections in children depend on the child's age, and may include any or all of the following:

Signs of a UTI in Infants

  • Fever
  • Irritability
  • Unable to be consoled
  • Vomiting and diarrhea
  • Loss of appetite
  • Failure to gain weight

Since these are generalized symptoms in most infants, the possibility of a urinary tract infection may be overlooked.

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Urinalysis and Culture

When you bring your child in for a urinary tract infection, we'll first discuss your child's general health and symptoms. Then we'll perform a urinalysis, which involves looking at your child's urine with a microscope. To be certain that there's an infection, we'll also do a urine culture to see if bacteria from the urine will grow in a culture medium. Your doctor will have the results of the urine culture after 24 hours. If there's an infection, an additional 24 hours is usually needed to find out which antibiotic will kill all of the bacteria.

The method of urine collection will affect the accuracy of the urine culture. It's important to:

  • Wash the skin around the urethra with a cleaning pad to remove bacteria on the skin surface.
  • If you collect the urine sample at home, place the sample in the refrigerator and then pack it in ice while traveling to the doctor's office.

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All children with urinary tract infections are treated with a safe and well-tolerated antibiotic selected to treat the specific bacteria causing the infection. Children with a bladder infection are usually treated with a seven-day course of medication. Children with kidney infections should be treated for 10 to 14 days. A child who's very ill or who has a kidney infection will most likely need to be hospitalized for intravenous antibiotics until the fever subsides and we've received the results of the urine culture.

Another urine culture will be performed while your child's taking the antibiotic or when the medication is finished, to make sure the infection is gone.

If your child hasn't had an X-ray evaluation, the antibiotics should be continued until the X-rays are done and our office has told you that it's safe to stop the antibiotics.

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Reviewed by health care specialists at UCSF Benioff Children's Hospital.

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UCSF Clinics & Centers

Urology Clinic
1825 Fourth St., Fifth Floor, 5B
San Francisco, CA 94158
Phone: (415) 353-2200
Fax: (415) 353-2480
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