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Urinary Tract Infection (UTI) in Children


The Manual's Editorial Staff

Reviewed/Revised Oct 2023
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The urinary tract includes the:

  • Kidneys (the 2 bean-shaped organs that make urine)

  • Ureters (the 2 tubes that drain urine from each kidney to the bladder)

  • Bladder (a balloon-like organ that holds urine until you're ready to urinate [pee])

  • Urethra (the tube that passes urine from your bladder to outside the body)

The Urinary Tract

The Urinary Tract

What is a urinary tract infection (UTI)?

A urinary tract infection (UTI) is a bacterial infection of some part of the urinary tract. The most common place for infection is the bladder.

  • UTIs are caused by germs (bacteria)

  • In babies, fever may be the only symptom of a UTI

  • Older children may feel pain or burning when urinating and a need to urinate often

  • Infant boys are more likely to get UTIs than infant girls, but older girls are much more likely to get UTIs than older boys

  • Doctors treat UTIs with antibiotics

What causes UTIs?

UTIs are caused by bacteria that get into the bladder and kidneys. Usually, bacteria from the skin get into the body through the urethra (the tube that passes urine out of the body).

UTIs are more likely to happen if your child has a birth defect of the urinary tract Overview of Kidney and Urinary Tract Birth Defects Birth defects are more common in the kidney and urinary system (urinary tract) than in any other system of the body. Defects can develop in the Kidneys—the two organs that filter waste from... read more . Birth defects often stop urine from flowing normally. Urine that doesn't flow normally is like stagnant water and is more likely to get infected. If a birth defect isn't treated, serious kidney problems can develop later on.

What are the symptoms of a UTI?

Symptoms vary by age.

In babies and children under 2 years old, symptoms may include:

  • Fever

  • Throwing up

  • Diarrhea (frequent, loose, watery poop)

  • Urine that smells very bad

Children over 2 have different symptoms depending on whether their bladder or kidneys are infected.

Children over 2 with a bladder infection may have:

  • Pain or burning when passing urine

  • The need to urinate often and suddenly

  • Pain in the bladder area (in the lower belly)

  • Urine that smells very bad

Children over 2 with a kidney infection may have:

  • Pain over one or both kidneys (in the side or back just above the waist)

  • High fever and chills

  • Feeling very sick

How can doctors tell if my child has a UTI?

Doctors do:

  • Urine tests (urinalysis) to look for white blood cells and bacteria in a urine sample

  • Urine culture to grow and identify any bacteria present

  • Imaging tests, such as ultrasound, to look at your child's bladder and kidneys

To get a urine sample from younger children and infants, doctors insert a soft thin tube (catheter) through their urethra. The urine sample is sent to a lab to see if any white blood cells and bacteria are in the urine. The urine will also be sent for culture to identify the type of bacteria and what antibiotic will kill these bacteria.

Sometimes your doctor will do tests to look for a birth defect in your child's urinary tract. Doctors usually do such tests if your child is under 3 years. They may also do such tests if your child is older and has had several UTIs or was very sick.

The first test is usually ultrasound Ultrasonography Ultrasonography is a safe imaging test that uses sound waves to create a moving picture of the insides of your body. Ultrasonography doesn't use radiation (x-rays). Ultrasonography is also called... read more Ultrasonography . If there is a problem with the urinary tract, doctors may do a test called voiding cystourethrography Cystography and cystourethrography There are a variety of tests that can be used in the evaluation of a suspected kidney or urinary tract disorder. (See also Overview of the Urinary Tract.) X-rays are usually not helpful in evaluating... read more , which looks at the connections between the bladder and kidneys. Doctors pass a catheter through your baby's urethra into the bladder, just as if collecting urine. A special liquid that shows up on x-rays is then placed into the bladder through the catheter, and x-rays are taken before and after your child urinates.

How do doctors treat UTIs?

How can I prevent my child from getting a UTI?

Some ways to help prevent UTIs include:

  • Have girls wipe from front to back after using the toilet to avoid getting bacteria in the urethra

  • Don't give children bubble baths, which may make it easier for bacteria to enter the urethra

  • Treat severe constipation (trouble passing hard stool) because it can also make urinating difficult and so lead to UTIs

  • Consider circumcision in boys with frequent UTIs

If your child has a birth defect of the urinary tract, doctors sometimes prescribe a daily dose of antibiotics to prevent UTIs.

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