Overview of urinary tract infection (UTI) in children
A urinary tract infection (UTI) in children is a fairly common condition. Bacteria that enter the urethra are usually flushed out through urination. However, when bacteria aren’t expelled out of the urethra, they may grow within the urinary tract. This causes an infection.
The urinary tract consists of the parts of the body that are involved in urine production. They are:
- two kidneys that filter your blood and extra water to produce urine
- two ureters, or tubes, that take urine to your bladder from your kidneys
- a bladder that stores your urine until it’s removed from your body
- a urethra, or tube, that empties urine from your bladder to outside your body
Your child can develop a UTI when bacteria enter the urinary tract and travel up the urethra and into the body. The two types of UTIs most likely to affect children are bladder infections and kidney infections.
When a UTI affects the bladder, it’s called cystitis. When the infection travels from the bladder to the kidneys, it’s called pyelonephritis. Both can be successfully treated with antibiotics, but a kidney infection can lead to more serious health complications if left untreated.
UTIs are most commonly caused by bacteria, which may enter the urinary tract from the skin around the anus or vagina. The most common cause of UTIs is E. coli, which originates in the intestines. Most UTIs are caused when this type of bacteria or other bacteria spread from the anus to the urethra.
UTIs occur more often in girls, especially when toilet training begins. Girls are more susceptible because their urethras are shorter and closer to the anus. This makes it easier for bacteria to enter the urethra. Uncircumcised boys under 1 year old also have a slightly higher risk of UTIs.
The urethra doesn’t normally harbor bacteria. But certain circumstances can make it easier for bacteria to enter or remain in your child’s urinary tract. The following factors can put your child at a higher risk for a UTI:
- a structural deformity or blockage in one of the organs of the urinary tract
- abnormal function of the urinary tract
- vesicoureteral reflux, a birth defect that results in the abnormal backward flow of urine
- the use of bubbles in baths (for girls)
- tight-fitting clothes (for girls)
- wiping from back to front after a bowel movement
- poor toilet and hygiene habits
- infrequent urination or delaying urination for long periods of time
Symptoms of a UTI can vary depending on the degree of infection and your child’s age. Infants and very young children may not experience any symptoms. When they do occur in younger children, symptoms can be very general. They may include:
Additional symptoms vary depending on the part of the urinary tract that’s infected. If your child has a bladder infection, symptoms may include:
- blood in the urine
- cloudy urine
- foul-smelling urine
- pain, stinging, or burning with urination
- pressure or pain in the lower pelvis or lower back, below the navel
- frequent urination
- waking from sleep to urinate
- feeling the need to urinate with minimal urine output
- urine accidents after the age of toilet training
If the infection has traveled to the kidneys, the condition is more serious. Your child may experience more intense symptoms, such as:
- chills with shaking
- high fever
- skin that’s flushed or warm
- nausea and vomiting
- side or back pain
- severe abdominal pain
- severe fatigue
The initial signs of a UTI in children can be easily overlooked. Younger children may have a difficult time describing the source of their distress. If your child looks sick and has a high fever without a runny nose, earache, or other obvious reasons for illness, consult their doctor to determine if your child has a UTI.
Prompt diagnosis and treatment of a UTI in your child can prevent serious, long-term medical complications. Untreated, a UTI can result in a kidney infection that may lead to more serious conditions, such as:
Contact their doctor immediately if your child has symptoms related to a UTI. A urine sample is required for their doctor to make an accurate diagnosis. The sample may be used for:
- Urinalysis. Urine is tested with a special test strip to look for signs of infection such as blood and white blood cells. In addition, a microscope may be used to examine the sample for bacteria or pus.
- Urine culture. This laboratory test usually takes 24 to 48 hours. The sample is analyzed to identify the type of bacteria causing the UTI, how much of it exists, and appropriate antibiotic treatment.
Collecting a clean urine sample can be a challenge for children who aren’t toilet trained. A usable sample can’t be obtained from a wet diaper. Your child’s doctor may use one of the following techniques to get your child’s urine sample:
- Urine collection bag. A plastic bag is taped over your child’s genitals to collect the urine.
- Catheterized urine collection. A catheter is inserted into the tip of a boy’s penis or into a girl’s urethra and into the bladder to collect urine. This is the most accurate method.
Your physician may recommend additional diagnostic tests to determine whether the source of the UTI is caused by an abnormal urinary tract. If your child has a kidney infection, tests also may be required to look for kidney damage. The following imaging tests may be used:
- kidney and bladder ultrasound
- voiding cystourethrogram (VCUG)
- nuclear medicine renal scan (DMSA)
- CT scan or MRI of the kidneys and bladder
A VCUG is an X-ray that’s taken while your child’s bladder is full. The doctor will inject a contrast dye into the bladder and then have your child urinate — typically through a catheter — to observe how the urine flows out of the body. This test can help detect any structural abnormalities that may be causing a UTI, and whether vesicoureteral reflux occurs.
A DMSA is a nuclear test in which pictures of the kidneys are taken after the intravenous (IV) injection of a radioactive material called an isotope.
The tests may be done while your child has the infection. Often, they’re done weeks or months after treatment to determine if there’s any damage from the infection.
Your child’s UTI will require prompt antibiotic treatment to prevent kidney damage. The type of bacteria causing your child’s UTI and the severity of your child’s infection will determine the type of antibiotic used and the length of treatment.
The most common antibiotics used for treatment of UTIs in children are:
- amoxicillin and clavulanic acid
- doxycycline, but only in children over age 8
If your child has a UTI that’s diagnosed as a simple bladder infection, it’s likely that treatment will consist of oral antibiotics at home. However, more severe infections may require hospitalization and IV fluids or antibiotics.
Hospitalization may be necessary in cases where your child:
- is younger than 6 months old
- has a high fever that isn’t improving
- likely has a kidney infection, especially if the child is very ill or young
- has a blood infection from the bacteria, as in sepsis
- is dehydrated, vomiting, or unable to take oral medications for any other reason
Pain medication to alleviate severe discomfort during urination also may be prescribed.
If your child is receiving antibiotic treatment at home, you can help ensure a positive outcome by taking certain steps.
During your child’s treatment, contact their doctor if symptoms worsen or persist for more than three days. Also call their doctor if your child has:
- a fever higher than 101˚F (38.3˚C)
- for infants, a new or persisting (lasting more than three days) fever higher than 100.4˚F (38˚C)
You should also seek medical advice if your child develops new symptoms, including:
- changes in urine output
With prompt diagnosis and treatment, you can expect your child to fully recover from a UTI. However, some children may require treatment for periods lasting from six months up to two years.
Long-term antibiotic treatment is more likely if your child receives a diagnosis of vesicoureteral reflex, or VUR. This birth defect results in the abnormal backward flow of urine from the bladder up the ureters, moving urine toward the kidneys instead of out the urethra. This disorder should be suspected in young children with recurring UTIs or any infant with more than one UTI with fever.
Children with VUR have a higher risk of kidney infection due to the VUR. It creates an increased risk of kidney damage and, ultimately, kidney failure. Surgery is an option used in severe cases. Typically, children with mild or moderate VUR outgrow the condition. However, kidney damage or kidney failure may occur into adulthood.
You can help reduce the possibility of your child developing a UTI with some proven techniques.
If your child gets repeated UTIs, preventive antibiotics are sometimes advised. However, they haven’t been found to decrease recurrence or other complications. Be sure to follow the instructions even if your child doesn’t have symptoms of a UTI.