What is the recommended treatment for a child with a urinary tract infection (UTI)?

Treatment of Urinary Tract Infections in Children

The recommended treatment for a child with a urinary tract infection (UTI) is age-appropriate antibiotic therapy with cephalosporins, amoxicillin-clavulanate, or trimethoprim-sulfamethoxazole (for children ≥2 months) for 7-14 days, with route of administration determined by the child's age, clinical status, and ability to tolerate oral medications. 1

Diagnosis Confirmation

• Definitive UTI diagnosis requires:
  • Pyuria and ≥50,000 CFU/mL of a single uropathogen, OR
  • Pure growth of 250,000 CFUs/mL with urinalysis showing bacteriuria or pyuria 1
• Urine specimen collection should occur before antibiotic administration
• Collection method:
  • Catheterization or suprapubic aspiration for non-toilet trained children
  • Clean-catch midstream for toilet-trained children 1

Treatment Algorithm by Age and Presentation

Neonates and Infants 8-21 days old

• First-line therapy:
  • Ampicillin IV/IM (150 mg/kg/day divided every 8h) PLUS
  • Either ceftazidime IV/IM (150 mg/kg/day divided every 8h) OR
  • Gentamicin IV/IM (4 mg/kg/dose every 24h) 1

Infants 22-60 days old

• First-line therapy:
  • Ceftriaxone IV/IM (50 mg/kg/dose every 24h) 1
  • Alternative dose: 75 mg/kg every 24 hours for severe infections

Children ≥2 months

• Oral options:
  • Cephalexin: 50-100 mg/kg/day in 4 divided doses
  • Cefixime: 8 mg/kg/day in 1 dose
  • Amoxicillin-clavulanate: 20-40 mg/kg/day in 3 doses
  • Trimethoprim-sulfamethoxazole: 8 mg/kg trimethoprim and 40 mg/kg sulfamethoxazole per day in 2 divided doses 1, 2

Important: Trimethoprim-sulfamethoxazole is not recommended for children less than 2 months of age 2

Parenteral vs. Oral Therapy Decision Points

• Use parenteral therapy when:

  • Patient is a young infant
  • Child appears toxic
  • Child is unable to retain oral medications
  • Compliance with oral medication is uncertain 1

• Switch from parenteral to oral therapy:

  • Once clinical improvement is observed
  • Usually within 24-48 hours 1

Duration of Treatment

• 7-14 days for UTIs in children 1
• 5-7 days may be sufficient for uncomplicated cystitis in older children 3
• 7 days for pyelonephritis in most hospitalized children with uncomplicated infections 3

Special Considerations

For ESBL-producing organisms

• Carbapenems (e.g., meropenem 60 mg/kg/day divided every 8 hours) 1
• Standard cephalosporins are ineffective against ESBL producers

Medication Restrictions

• Fluoroquinolones: Generally not recommended in children due to safety concerns
• Nitrofurantoin:
  • Not for febrile UTIs (inadequate tissue concentrations for pyelonephritis)
  • Contraindicated in infants <4 months (risk of hemolytic anemia) 1

Follow-up and Imaging

• Renal and bladder ultrasound (RBUS) after first febrile UTI 1
• Voiding cystourethrography (VCUG) indicated if:
  • RBUS reveals hydronephrosis, scarring
  • Findings suggest high-grade VUR or obstructive uropathy 1

Treatment Response Monitoring

• Clinical improvement should be seen within 48-72 hours
• If symptoms persist despite appropriate antibiotic therapy, consider:
  • Imaging studies
  • Reassessment of antibiotic choice based on culture results 1

Common Pitfalls to Avoid

• Failing to collect urine specimen before starting antibiotics
• Using contaminated urine specimens for diagnosis
• Prescribing nitrofurantoin for febrile UTIs or in infants <4 months
• Not adjusting empiric therapy based on culture results
• Unnecessary imaging for first UTI with good treatment response
• Using trimethoprim-sulfamethoxazole in infants less than 2 months of age 1, 2