Urinary Tract Infections in Children
What is a urinary tract infection (UTI)?
A urinary tract infection (UTI) is a problem that happens when germs (called bacteria) get into the urinary tract and cause an infection.
Your child's urinary tract is the system that makes urine and carries it out of your child's body. It includes the bladder and the kidneys and the tubes that connect them. Most UTIs are bladder infections.
UTIs in children must be treated right away. A UTI that is not treated quickly can lead to a kidney infection.
What causes it?
Most UTIs in children are caused by germs (bacteria) that enter the urethra. The germs then travel up the urinary tract and cause infection. Germs that normally are in stool are the most common cause. Being constipated or not emptying the bladder all the way can lead to a buildup of bacteria.
What are the symptoms?
Symptoms of a UTI in an infant or young child may include a fever. This may be the only symptom in infants. Other symptoms include being fussy or not being hungry. Older children are more likely to have symptoms, such as pain, the need to urinate often, or burning when urinating.
How is it diagnosed?
To diagnose a UTI, your doctor will test a sample of your child's urine to see if it has germs that cause infections. Your doctor will also ask about your child's symptoms and do a physical examination. Your child may need more testing to find the cause of the UTI.
How is a UTI treated?
Treatment for most children with a UTI is oral antibiotics and home care. Home care includes helping your child drink extra fluids when you notice symptoms and urging your child to urinate often. Children who are very young or sick may get a shot of antibiotics. Or your child may need treatment in a hospital.
Most UTIs in children are caused by germs (bacteria) that enter the urethra. The germs then travel up the urinary tract. Germs that normally live in the large intestine and are in stool (feces) are the most common cause of infection. Sometimes germs travel through the blood or lymph system to the urinary tract and can cause kidney or bladder infections.
The ways that a buildup of bacteria can occur include:
- Having bacteria normally found around the anus that get into the urethra and cause a UTI.
- Being constipated.
- Not emptying the bladder all the way. This can cause bacteria to build up in urine.
Sometimes a child's body can't get rid of all the urine. This can lead to UTIs in infants and young children. This may happen if a problem in the bladder allows urine to flow backward. Or it can happen if something blocks or slows the flow of urine.
What Increases Your Risk
Risk factors that increase your child's risk of getting a UTI include:
- Kidney stones and other things that block the flow of urine.
- Problems with the structure or the function of the urinary tract that limit the ability of the kidney or bladder to empty of urine. These problems may be present at birth or may develop soon after.
- Not urinating often enough, not emptying the bladder all the way, or being constipated. These are common during toilet training. They make it easier for bacteria to build up in the urine.
- An uncircumcised penis. The foreskin can trap bacteria, which can then enter the urinary tract.
- Having a catheter in place. This is done in a hospital when children can't urinate on their own. Bacteria can enter the catheter.
- Previous UTIs. Each UTI raises the risk of future UTIs.
- A parent or sibling having had UTIs or the backward flow of urine from the bladder into the kidneys (vesicoureteral reflux).
UTIs in children may not cause obvious urinary symptoms. Symptoms of a UTI in an infant or young child may include:
- A fever. This may be the only symptom in infants.
- Being fussy.
- Not being hungry.
- Failure to gain weight or develop normally.
- Urine that smells bad.
- Crying during urination.
- Vomiting or diarrhea.
Older children are more likely to have symptoms such as:
- Pain or burning when urinating.
- The need to urinate often, but usually passing only small amounts of urine.
- Loss of bladder control, new bedwetting, or other changes in urination habits.
- Lower belly pain.
- Urine that is red, pink, cloudy, or that smells bad.
- Pain in the flank. This is felt just below the rib cage and above the waist on one or both sides of the back.
In a UTI, bacteria usually enter the urinary tract through the urethra. They may then travel up the urinary tract and infect the bladder and the kidneys. Most UTIs in children clear up quickly with antibiotic treatment.
Infants and young children often get another UTI after their first UTI. If an infection comes back (recurs), it usually happens within the same year as the first UTI.
Recurrent UTIs in a child can mean that there is a problem with the structure or function of the urinary tract. Your child's doctor will treat any problems like this because repeated infections raise the risk of lasting kidney damage. In some cases, children may need surgery.
UTIs can lead to a serious infection throughout the body called sepsis. Problems from a UTI are more likely to happen in babies who are born too soon, in newborns, and in babies who have something blocking the flow of urine.
When to Call a Doctor
UTIs in infants and young children need early evaluation and treatment. Call your doctor to make an appointment within 24 hours if your child has:
- A fever.
- Urine that looks pink, red, brown, or cloudy or is foul-smelling.
- Burning pain with urination.
- Frequent need to urinate without being able to pass much urine.
- Pain in the flank, which is felt just below the rib cage and above the waist on one or both sides of the back.
- Vaginal discharge with urinary symptoms.
- Symptoms similar to those of a previous UTI.
Call the doctor if your child isn't feeling better within 48 hours after starting an antibiotic.
Watchful waiting is not the right choice if you suspect that your child has a urinary tract infection. Untreated UTIs in children can lead to other kidney problems, high blood pressure, and other complications.
Examinations and Tests
To diagnose a UTI, your doctor will ask for a sample of your child's urine. It's tested to see if it has germs that cause bladder infections. Your doctor will also ask about your child's health and do a physical examination.
If your doctor thinks your child has a UTI, the doctor may have your child start taking antibiotics right away before getting the results of the test.
Your doctor may do other tests if your child has a UTI and:
- Is younger than 2 years old and has a fever.
- Doesn't get better after 4 days of medicine.
- May have a problem with the urinary tract.
- Has had kidney or bladder problems that could make the UTI harder to treat.
- May be infected with unusual bacteria that won't respond to the usual treatment.
Treatment for most children with a UTI is oral antibiotics and home care. Home care includes helping your child drink extra fluids as soon as you notice symptoms. And it includes urging your child to urinate often.
Infants and young children with a UTI need early treatment. This is to prevent kidney damage or widespread infection (sepsis). Your doctor is likely to start treating your child based on the symptoms and urine test.
Sometimes the doctor may give your child a shot of antibiotics. This can happen if your child is younger than 3 months, is too nauseated or sick to take oral medicines, or has an impaired immune system. Or your child may need antibiotics given through a vein (IV). This is given in a hospital. After your child's fever and other symptoms improve and your child is feeling better, the doctor may give your child oral antibiotics.
- If the doctor prescribed antibiotics for your child, give them as directed. Do not stop using them just because your child feels better. Your child needs to take the full course of antibiotics.
- The doctor may also give your child a medicine to ease the burning pain of a UTI. This will often turn the urine red or orange. The urine will return to its normal colour after your child stops the medicine.
- Try to get your child to drink extra fluids for the next 24 hours. This will help flush bacteria out of the bladder. Do not give your child drinks that have caffeine or that are carbonated. They can make the bladder sore.
- Tell your child to urinate often and to empty the bladder each time.
- A warm bath may help your child feel better. Soaps and bubble baths can cause irritation. Wait until the end of the bath to use soap.
Preventing future UTIs
- Make sure that your child drinks plenty of water each day. This helps your child urinate often, which clears bacteria from the body.
- Encourage your child to urinate as soon as they need to.
- Offer your child foods with fibre such as fruits, vegetables, and whole grains. This can help your child have regular stools that are soft and pass easily. Preventing constipation may also help prevent UTIs.
Antibiotic medicine that your child takes by mouth (an oral medicine) usually works well to treat UTIs. In many cases, if the symptoms and a urine test suggest a UTI, the doctor will start the medicine without waiting for the results of a urine culture.
The doctor may give antibiotics as a shot or through a vein (IV) if your child is:
- Younger than 3 months.
- Too ill or nauseated to take oral medicine.
- Very sick with a severe kidney infection.
The doctor may start oral medicine treatment after your child is stable and feels better.
The doctor may consider antibiotics to prevent another infection if tests show a problem in the urinary tract that raises the child's risk for recurrent UTIs.
Treatment to prevent UTIs may last 3 months or longer. Some doctors are more careful about giving antibiotics for long-term use. This is because of concerns about the growth of antibiotic-resistant bacteria.
- Abdominal Pain, Age 11 and Younger
- Bedwetting in Children
- Constipation, Age 11 and Younger
- Kidney Stones
- Toilet Training
- Urinary Problems and Injuries, Age 11 and Younger
- Urinary Problems and Injuries, Age 12 and Older
- Urinary Tract Infections in Teenagers and Adults
- Using Antibiotics Wisely
- Vesicoureteral Reflux (VUR)
Current as of: March 1, 2023
Author: Healthwise Staff
John Pope MD - Pediatrics
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Susan C. Kim MD - Pediatrics
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