Urinary tract infections (UTIs) are common in young children, especially girls. Most UTIs happen when bacteria enter the body through the urethra, the small tube that carries urine (pee) out of the body. From there, the bacteria can travel up into the bladder, where urine is stored. Sometimes, the infection moves farther into the urinary tract to the kidneys, which filter waste from the blood and make urine.
In infants, UTIs may also be caused by bacteria carried through the bloodstream to the kidneys from another part of the body
Types of UTIs
A UTI is a general term for infections that can happen in different parts of the urinary tract. The name depends on which part of the body is affected.
Cystitis: bladder infection
Pyelonephritis: kidney infection
Urethritis: infection of the urethra
The bladder is the area most commonly infected. Usually, cystitis is caused by bacteria that get into the urinary tract through the urethra. The urethra is very short in females, so bacteria that live on the skin, in the colon and in the vagina can get into the bladder easily. Fortunately, these bacteria normally wash out when urinating.
Symptoms of a UTI in children
A bladder infection an cause lower abdominal pain, vomiting, tenderness, pain during urination, frequent urination, blood in the urine, recurrence of day or nighttime wetting in a previously toilet-trained child and a low-grade fever.
Infection of the kidneys will cause more general abdominal pain and a higher fever, but it may or may not cause frequent and painful urination.
In general, UTIs in infants and young children (up to 2 years of age) may have few recognizable signs or symptoms other than a fever; they also have a greater potential for causing kidney damage than those occurring in older children.
What to do if you think your child may have a UTI
Urinary tract infections must be treated with antibiotics as quickly as possible, so you should notify your pediatrician promptly if you suspect your child has developed one. This is especially the case for infants, in whom an unexplained high fever (that is, not explained by a respiratory infection or diarrhea) may be the only sign of a urinary tract infection.
If your infant has a fever with no other symptoms for more than 3 days, make sure to talk with your pediatrician.
Diagnosing and treating UTIs in children
When a urinary tract infection is suspected, particularly in a child with symptoms, your pediatrician will measure their blood pressure (since an increase in blood pressure can be a sign of a related kidney problem). They'll also examine them for lower abdominal tenderness that might indicate a UTI. An examination of the genitals may be performed to rule out a yeast infection or genital irritation.
Your doctor will want to know what your child has been eating and drinking, because certain foods can irritate the urinary tract, causing symptoms similar to those of an infection. Constipation (infrequent or hard-to-pass stools) can also cause symptoms similar to those of a UTI.
Collecting a urine sample
Your pediatrician also will want a urine sample from your child for analysis. In infants and toddlers who are not toilet trained, the pediatrician may start with a special bag over the genitals designed to catch urine. If this urine appears possibly infected, however, then urine must be collected by using a catheter to confirm the diagnosis.
In toilet trained children, the urine can be collected by the "clean catch" method. First, you'll use soap and water or special wipes provided by your pediatrician to cleanse the urethral opening (with an uncircumcised penis, hold the foreskin back). Then allow your child to start to pee, but wait just a moment before you start to collect urine in the special container provided by the doctor. In this way, any bacteria around the outside of the urethral opening will be washed away by the early urine released and won't contaminate the sample. (Also see, "How to Collect a Urine Sample from a Baby.")
In rare cases, a doctor may perform a suprapubic tap, in which a small needle is inserted through the skin of the lower abdomen into the bladder. The urine that is collected will be examined for any sign of blood cells or bacteria, and special tests (cultures) will be done to identify the bacteria.
Antibiotic treatment for UTIs
If a UTI is suspected, your child will be started on an antibiotic, Depending on what the results of the culture show, however, the particular antibiotic may need to be changed. In agreement with guidelines for the treatment of UTI in infants and children (up to age 24 months), your pediatrician may prescribe antibiotics for a total of 7 to 14 days.
Prompt treatment is important to eliminate the infection and prevent its spread, and also to reduce the chances of kidney damage. It is important to take the full course of antibiotics, even if the discomfort resolves after a few days of treatment. Otherwise, the bacteria may grow again, causing further infection and more serious damage to the urinary tract.
When imaging tests may be needed for a UTI
Sometimes, children with urinary tract infections may need imaging tests to take a closer look at their urinary tract. These tests can include ultrasounds, x‑rays or other scans that help doctors see the kidneys and bladder.
Whether imaging is needed depends on your child's age and how many UTIs they've had. Your pediatrician may also order other tests to check how well your child's kidneys are working.
If test results suggest a problem with the shape or structure of the bladder, ureters (the tubes that carry urine from the kidneys to the bladder) or kidneys, your child may be referred to a specialist. This could be a pediatric urologist or pediatric nephrologist, doctors who focus on the urinary system and kidneys in children.
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