What is the recommended treatment for pediatric patients with cystitis (urinary bladder inflammation)?

Treatment of Pediatric Cystitis

First-Line Antibiotic Selection

For uncomplicated cystitis in children older than 2 months, nitrofurantoin is the preferred first-line agent, with clinical cure rates of 88-93% and bacteriological cure rates of 81-92%. 1

Recommended First-Line Options:

• Nitrofurantoin: 5-7 mg/kg/day divided in 4 doses (preferred for uncomplicated cystitis in children >2 months) 1
• Amoxicillin-clavulanate: 20-40 mg/kg/day in 3 doses 1
• Cephalosporins (cefixime, cefpodoxime, cephalexin, cefprozil, cefuroxime axetil): Various dosing schedules available 2, 1, 3
• Trimethoprim-sulfamethoxazole: 6-12 mg/kg trimethoprim and 30-60 mg/kg sulfamethoxazole per day in 2 doses, ONLY if local E. coli resistance is <20% 1, 3, 4

Critical Antibiotic Selection Pitfalls:

• Never use amoxicillin or ampicillin empirically due to very high worldwide resistance rates and poor efficacy 1
• Avoid fluoroquinolones as first-line therapy in children due to musculoskeletal safety concerns; reserve only for severe infections where benefits outweigh risks 3
• Do not use nitrofurantoin if fever is present or pyelonephritis is suspected, as it does not achieve adequate tissue concentrations to treat upper tract infections 2, 3, 5
• Trimethoprim-sulfamethoxazole resistance has increased significantly, with E. coli resistance reaching 19-63% in some studies, making it unreliable unless local susceptibility data confirm <20% resistance 2, 1

Treatment Duration

Shorter courses of 3-5 days produce comparable outcomes to longer courses for uncomplicated cystitis in children older than 2 months. 1, 3

• For uncomplicated cystitis (afebrile): 3-5 days of oral antibiotics is adequate 1, 3, 6
• For febrile UTI/pyelonephritis: 7-14 days of therapy is required 2, 1
• Evidence shows 5-day treatment achieves 96% symptom resolution for cystitis 1, 6
• Treating for less than 3 days may be inadequate 3

Route of Administration

Oral therapy is sufficient for uncomplicated cystitis in children who can tolerate oral medications and do not appear toxic. 1, 3

• Parenteral therapy should be reserved for children who appear "toxic," are unable to retain oral intake (including medications), or when compliance with oral medication is uncertain 2
• Initiating treatment orally or parenterally is equally efficacious for UTI, with route selection based on practical considerations 1

Diagnostic Requirements Before Treatment

• Always obtain urine culture and susceptibility testing before starting antibiotics to confirm diagnosis and guide therapy adjustments 3
• Diagnosis requires both pyuria (positive leukocyte esterase or WBCs on microscopy) AND ≥50,000 CFU/mL of a single uropathogen on culture 1, 3

Monitoring Response to Treatment

• Clinical improvement is expected within 24-48 hours of starting appropriate antibiotics 2, 3
• If symptoms persist beyond 48 hours, this constitutes an "atypical" UTI requiring reevaluation for antibiotic resistance or anatomic abnormalities 2, 3
• Routine follow-up visits after first acute cystitis may not be necessary if bacteria are sensitive to prescribed antibiotic and there is no history of defective bladder or bowel emptying 6

When to Treat as Complicated UTI (7-14 Days)

Longer treatment duration is required if any of the following are present:

• Fever present (suggests pyelonephritis) 3
• Known urologic abnormalities or vesicoureteral reflux 3
• Immunocompromised state 3
• Poor response to antibiotics within 48 hours 2, 3
• Non-E. coli organism 2, 3
• Elevated creatinine 2
• Sepsis or seriously ill appearance 2

Imaging Considerations

• Routine imaging is NOT indicated for first uncomplicated cystitis with good response to treatment in children over 2 years of age 2, 3
• Renal and bladder ultrasound IS indicated for all febrile infants with first UTI, children with recurrent UTIs, or atypical presentations 2
• Voiding cystourethrography (VCUG) should be performed after a second febrile UTI, not routinely after the first 2

Special Considerations by Age

Neonates (<28 days):

• Require hospitalization with parenteral antibiotics (amoxicillin and cefotaxime) 7
• Complete 14 days of therapy 7

Infants 28 days to 2 months:

• Nitrofurantoin is contraindicated in infants <2 months of age 4
• Use cephalosporins or amoxicillin-clavulanate instead 1

Children >2 months with uncomplicated cystitis:

• Nitrofurantoin is preferred 1
• 3-5 day oral course is adequate 1, 3

Antibiotic Selection Based on Renal Function

• Do not use nitrofurantoin when eGFR <30 mL/min as it becomes ineffective and potentially toxic in renal impairment 1
• For trimethoprim-sulfamethoxazole, reduce dosage when creatinine clearance is 15-30 mL/min to half the usual regimen; use is not recommended below 15 mL/min 4