Urinary Tract Infections in Children: Signs, Treatment, and Prevention

Urinary tract infections are far more common in children than most parents realize. In fact, UTIs are one of the most frequent bacterial infections in young children, and they are particularly easy to miss because the symptoms look very different in babies and toddlers than in older children or adults.

At Hummingbird Pediatrics in Robbinsville, we want families across Hamilton, West Windsor, Bordentown, and Mercer County to know what to watch for — because a missed UTI can progress to a kidney infection, and in young children, kidney damage from recurrent UTIs can affect long-term kidney health.

Who Gets UTIs?

• **Infant girls under 1 year**: high anatomical susceptibility
• **Girls of all ages**: girls are significantly more likely than boys to get UTIs because of their shorter urethra, which allows bacteria to reach the bladder more easily
• **Uncircumcised infant boys under 1 year**: uncircumcised boys have a higher UTI risk in the first year of life than circumcised boys
• **Children with vesicoureteral reflux (VUR)**: a structural condition where urine flows backward from the bladder toward the kidneys, increasing infection risk
• **Children who are toilet training or recently trained**: holding urine and incomplete bladder emptying increase risk

How UTI Symptoms Differ by Age

This is the most important section for parents to understand, because symptoms vary dramatically by developmental stage.

Infants and Babies (Under 2 Years)

• Unexplained fever with no obvious source (no runny nose, no ear pain, no rash)
• Unusual fussiness or crying, especially during or after urination (though this is hard to detect)
• Foul-smelling urine or urine that looks cloudy or darker than usual
• Poor feeding or vomiting
• Failure to gain weight as expected

Any baby under 2 with an unexplained fever should be evaluated for a UTI.

Toddlers and Preschoolers (Ages 2–5)

• Fever, sometimes with no other explanation
• New daytime accidents in a child who was previously toilet-trained
• Complaints of belly pain or back pain (lower back or side)
• Crying or unusual discomfort during urination
• Increased frequency of urination or urgent requests to use the bathroom
• Foul-smelling or discolored urine

School-Age Children and Adolescents (Ages 6+)

• Burning or stinging with urination
• Frequent, urgent need to urinate (often producing very little urine)
• Lower abdominal pain or pressure
• Blood in the urine (pink, red, or cola-colored urine)
• Foul-smelling urine
• Low-grade fever

When fever is high (above 102°F) and accompanied by flank or back pain, this suggests the infection may have spread to the kidneys (pyelonephritis) — which requires prompt treatment.

How Is a UTI Diagnosed?

Diagnosis requires a urine sample. For toilet-trained children, a midstream clean-catch sample is collected. For infants and young children who are not yet toilet-trained, a catheterized urine sample (collected through a thin tube) is the most reliable method and avoids contamination from skin bacteria.

A urine dipstick and microscopy can provide rapid results, but a urine culture — which grows the bacteria and identifies the best antibiotic — is the definitive test and guides treatment.

Treatment

• The child's age
• The type of bacteria identified on culture
• Whether the infection appears confined to the bladder (cystitis) or has spread to the kidneys (pyelonephritis)

Most uncomplicated bladder infections in older children are treated with a 3–7 day oral antibiotic course. Kidney infections, or UTIs in infants and young children at higher risk for complications, are treated for longer and sometimes require IV antibiotics if oral medication cannot be tolerated.

Always complete the full course of antibiotics even if symptoms improve within 1–2 days.

After a UTI: Does My Child Need Follow-Up Imaging?

• A first febrile UTI (with fever) in children under 2 years, to evaluate for vesicoureteral reflux (VUR) or structural kidney abnormalities
• Recurrent UTIs in children of any age

Renal ultrasound is often the first imaging study. Voiding cystourethrogram (VCUG) may be recommended if reflux is suspected. Your pediatrician will guide you through these decisions based on your child's specific history.

Preventing UTIs in Children

Complete prevention is not always possible, but these strategies reduce risk:

• **Encourage frequent urination** — Don't let your child hold urine for long periods. Encourage bathroom breaks every 2–3 hours at school.
• **Ensure complete bladder emptying** — Encourage your child to "double void" (wait a moment after urinating, then try again) if they tend to rush.
• **Wipe front to back** — For girls, this is critical to prevent fecal bacteria from reaching the urethra.
• **Cotton underwear and loose clothing** — Breathable fabric reduces moisture that encourages bacterial growth.
• **Adequate fluid intake** — Good hydration dilutes urine and helps flush bacteria.
• **Avoid bubble baths** — Bubble bath can irritate the urethra and increase susceptibility to infection.
• **Treat constipation** — A full rectum can press on the bladder and impair complete emptying. Constipation is a major and often-overlooked UTI risk factor.

When to Call Us

• Unexplained fever without an obvious source, especially in infants and toddlers
• Burning or pain with urination
• Blood in the urine
• A fever that returns after completing a UTI treatment course (this suggests the infection may not have cleared)
• More than one UTI in 6 months

We will evaluate your child, order a urine sample when appropriate, and determine whether further follow-up imaging or specialist involvement is needed. Most UTIs in children are straightforward to treat when caught early — the key is not waiting to see if symptoms improve on their own.