Pediatric UTI Treatment Guidelines
For pediatric urinary tract infections (UTIs), oral cephalosporins such as cephalexin (50-100 mg/kg/day divided in 4 doses) or cefixime (8 mg/kg/day in 1 dose) are recommended as first-line treatment options based on local resistance patterns. 1
First-Line Antibiotic Options
- Oral options (uncomplicated UTI/cystitis):
- Cephalexin: 50-100 mg/kg/day divided in 4 doses
- Cefixime: 8 mg/kg/day in 1 dose
- Amoxicillin-clavulanate: 45 mg/kg/day divided in 2 doses
- Trimethoprim-sulfamethoxazole (TMP-SMX): Only if local resistance <20%
- Nitrofurantoin: 5-7 mg/kg/day divided in 4 doses (not for pyelonephritis)
The American Academy of Pediatrics recommends avoiding amoxicillin as first-line therapy due to high resistance rates (median 75% of E. coli isolates resistant) 1.
Treatment Based on Age and Severity
Neonates (<28 days)
- Require hospitalization
- Parenteral therapy: Amoxicillin and cefotaxime
- Duration: 14 days (may transition to oral after 3-4 days of clinical improvement)
Infants (28 days to 3 months)
- If clinically ill: Hospitalization with parenteral 3rd generation cephalosporin or gentamicin
- If not acutely ill: Outpatient management with daily parenteral ceftriaxone or gentamicin until afebrile for 24 hours
- Duration: 14 days (complete with oral antibiotics after clinical improvement)
Children with Pyelonephritis
- Complicated: Hospitalization with parenteral ceftriaxone or gentamicin until clinical improvement
- Uncomplicated: Outpatient parenteral ceftriaxone or gentamicin until afebrile for 24 hours
- Duration: 7-14 days (complete with oral antibiotics)
Children with Cystitis
- Duration: 5-7 days of oral antibiotics 1, 2
- Clinical improvement expected within 48-72 hours of appropriate therapy
Treatment Duration Guidelines
- Uncomplicated UTI/cystitis: 5-7 days
- Pyelonephritis/febrile UTI: 7-14 days
- Neonates and young infants: 14 days
Diagnostic Considerations
- Always obtain urine culture before starting antibiotics to guide therapy
- Diagnosis requires pyuria and ≥50,000 CFUs/mL of a single pathogen in properly collected specimen
- Clinical reassessment within 48-72 hours of initiating treatment
Imaging Recommendations
- Renal ultrasound recommended for first febrile UTI to detect anatomical abnormalities
- Routine voiding cystourethrography (VCUG) after first UTI not recommended unless:
- Ultrasound reveals hydronephrosis, scarring, or findings suggesting high-grade vesicoureteral reflux
- Recurrence of febrile UTI
Special Considerations
- Male infants under 12 months have higher risk (10-20%) of underlying urological abnormalities 1
- Consider circumcision in male infants with recurrent UTIs
- Fluoroquinolones should be limited due to concerns about arthropathy/arthralgia
- For Streptococcus pyogenes infections, treatment should continue for at least 10 days 3
Prevention Strategies
- Ensure adequate hydration
- Address bowel and bladder dysfunction if present
- Promote proper hygiene practices
- Consider continuous antibiotic prophylaxis only for high-risk children (high-grade VUR or recurrent breakthrough febrile UTIs)
Follow-up Recommendations
- Clinical reassessment within 48-72 hours of initiating treatment
- Instruct parents to seek prompt medical evaluation for future febrile illnesses
- Long-term follow-up to identify predisposing abnormalities and monitor for scarred kidneys
The evidence strongly supports using narrow-spectrum antibiotics when possible, with one study showing that increased empiric cephalexin prescribing did not result in increased treatment failures or adverse outcomes compared to broader-spectrum alternatives 4.