Am Fam Physician. 1999;59(6):1485-1486
See related article on pediatric urinary tract infection and reflux.
What is a urinary tract infection?
A urinary tract infection (called “UTI” for short) refers to an infection anywhere in the urinary tract. The urinary tract is made up of the kidneys, the ureters (tubes that drain urine from the kidneys to the bladder), the bladder and the urethra. The kidneys remove waste from the blood and the waste comes out as urine. Since the urinary tract opens to the outside of the body, germs can find their way into the urinary tract. Sometimes these germs grow very fast and cause you to have an infection. Germs may also get to the urinary tract through your blood, but this doesn't happen very often.
The two most common types of UTIs are bladder infections and kidney infections. When the bladder is infected, it means that germs have only made it to the bladder and not up to the kidneys. Symptoms of a bladder infection are: having to urinate more often (frequency), not being able to wait to urinate (urgency) and a burning feeling during urination. Children who have a bladder infection may not be able to hold their urine (incontinence). They may also have lower abdominal pain and a mild fever.
Children who have a kidney infection usually feel worse because of a high fever and pain in their back, usually on one side. Kidney infections often start out as bladder infections that move up into the kidneys.
What is reflux?
When urine from the bladder flows back up into the kidneys, this is called reflux. Urine normally goes only one way. When urine flows back up from the bladder to the kidneys, germs get into the kidneys. This can lead to kidney infections. If reflux isn't noticed, the repeated infections can lead to scarring of the kidneys. Reflux happens in about one third of children who have a UTI.
How will my doctor know if my child has a UTI?
Two tests can tell your doctor if you have a UTI. One is a urinalysis. This test looks for germs and white blood cells in the urine. White blood cells are a sign that the bladder is irritated. If the test shows white blood cells, your doctor may send the urine for a urine culture. This test takes 24 to 48 hours. The urine is placed in a special container to see whether bacteria is growing in the urine.
How is a UTI treated?
UTIs are treated with antibiotics. Most UTIs can be treated at home with an antibiotic that is taken by mouth. It's important that your child take all of the antibiotics, even if he or she is feeling better within a day or two. To kill all the bacteria, all the medicine needs to be taken.
Does a UTI mean there is something wrong with my child's urinary tract?
Most children who have a UTI have a normal urinary tract. Just as some children get ear infections even though their ears are normal, some children get UTIs even though they have a normal urinary tract. However, some children with UTIs may have something wrong with their urinary tract. The doctor may order special tests to find out. This is more likely if your child is very young at the time of his or her first infection, or if he or she has repeated infections.
What kind of tests will the doctor perform?
There are several tests that look at the urinary tract. An ultrasound of the kidneys and bladder is a painless test that gives your doctor a good look at the kidneys and bladder.
A bladder x-ray, called a voiding cystourethrogram (VCUG), is a good way to look at the bladder. A small tube is put into your child's bladder. A liquid is passed through the tube into the bladder. This liquid shows up on x-ray. X-rays are then taken as the bladder fills and while your child urinates. This study gives good pictures of the bladder and urethra. It is also used to see if your child has reflux.
Another test that is sometimes used in children with UTIs is a kidney scan. For this test, a small amount of radioactive medicine is put into your child's blood stream with an IV line. Pictures of the kidneys are then taken with a special camera. This is a very good test for finding scarring in the kidneys. It is most commonly used in children known to have reflux.
An intravenous pyelogram is another test that can be used to look at the kidneys and urinary tract. It is a lot like a kidney scan.
Which of these tests is ordered for your child depends on your child's age, gender, how many infections he or she has had, and how bad the infections were.
What can I do to help my child stop getting UTIs?
One of two things may be causing your child to have UTIs. Your child could have bladder instability. This means that the bladder tries to empty before it has filled, and the child can't control it. Children with bladder instability may do a “potty dance” where they will suddenly squat or dance around when they need to urinate.
You can help your child's bladder instability by having him or her go to the bathroom every two or three hours, whether he or she feels the need to go or not (this is called “timed voiding”). Timed voiding will empty your child's bladder before it tries to empty on its own. If the problem does not get better after you try timed voiding, your doctor may recommend some medicine to relax your child's bladder.
The other problem that can lead to repeated UTIs is constipation. If your child has a bowel movement less than three or four times a week or has large, hard bowel movements, then he or she is probably constipated. Your doctor may want you to make changes in your child's diet, or he or she might give your child medicine.