What is the recommended management for a patient with a urinary tract infection (UTI)?

Management of Urinary Tract Infection

For uncomplicated UTI in women, use first-line therapy with nitrofurantoin, trimethoprim-sulfamethoxazole (TMP-SMX), or fosfomycin based on local resistance patterns, treating for no longer than 7 days. 1

Diagnostic Approach

Obtain urine culture and sensitivity testing before initiating antibiotics in patients with recurrent UTIs or complicated infections to guide therapy and document bacterial etiology. 1 For simple acute cystitis in otherwise healthy women, diagnosis can be made clinically without office visit or culture if symptoms are classic (dysuria, frequency, urgency). 2

Key Diagnostic Considerations:

• Urinalysis with culture is mandatory for recurrent UTI patients before each treatment episode to establish microbial confirmation and track resistance patterns 1
• Obtain catheterized specimen if initial collection suggests contamination 1
• Significant bacteriuria is defined as ≥50,000 CFU/mL of a single uropathogen in children 2-24 months 1
• Do not routinely perform cystoscopy or upper tract imaging for uncomplicated recurrent UTI 1

Antibiotic Selection Algorithm

For Uncomplicated Cystitis (Lower UTI):

First-line agents (choose based on local antibiogram): 1

• Nitrofurantoin monohydrate/macrocrystals: 100 mg twice daily for 5-7 days 2
• Trimethoprim-sulfamethoxazole: 160/800 mg (1 DS tablet) twice daily for 3 days 3, 2
  • Only use if local E. coli resistance is <20% 1, 4
• Fosfomycin trometamol: 3 g single dose 2

Avoid as first-line empiric therapy:

• Fluoroquinolones should be reserved for pyelonephritis or complicated infections due to collateral damage (selection of multidrug-resistant organisms) 1, 4
• β-lactam agents (amoxicillin-clavulanate, cefpodoxime) are less effective empirically 2

For Uncomplicated Pyelonephritis (Upper UTI):

Oral regimens (if patient can tolerate oral intake and is not toxic-appearing): 1

• Ciprofloxacin: 500-750 mg twice daily for 7 days 1
• Levofloxacin: 750 mg once daily for 5 days 1
• TMP-SMX: 160/800 mg twice daily for 14 days (only if fluoroquinolone resistance <10%) 1
• Cefpodoxime: 200 mg twice daily for 10 days 1

Consider initial IV dose of long-acting parenteral agent (e.g., ceftriaxone) before transitioning to oral therapy 1

Parenteral regimens (for toxic-appearing patients or inability to retain oral medications): 1

• Ceftriaxone: 1-2 g once daily 1
• Ciprofloxacin: 400 mg twice daily 1
• Levofloxacin: 750 mg once daily 1

For Complicated UTI:

Complicated UTI includes: obstruction, foreign body, incomplete voiding, vesicoureteral reflux, recent instrumentation, male sex, pregnancy, diabetes, immunosuppression, healthcare-associated infection, or multidrug-resistant organisms. 1

• Obtain urine culture before treatment and tailor therapy based on sensitivities 1
• Select empiric therapy based on local resistance patterns and illness severity 1
• Treat for 7-14 days (14 days for men when prostatitis cannot be excluded) 1
• Address underlying urological abnormality - this is mandatory for cure 1
• Broader microbial spectrum expected: E. coli, Proteus, Klebsiella, Pseudomonas, Serratia, Enterococcus 1

For Recurrent UTI (≥2 infections in 6 months or ≥3 in 12 months):

• Culture every symptomatic episode before treatment to document recurrence and guide therapy 1
• Use same first-line agents as uncomplicated cystitis 1
• Treat for ≤7 days - avoid prolonged courses 1
• Consider patient-initiated self-start treatment for select patients while awaiting culture results 1
• If resistant to oral antibiotics, use culture-directed parenteral therapy for ≤7 days 1

Treatment Duration

Key principle: Use the shortest effective duration to minimize resistance. 1

• Uncomplicated cystitis: 3-7 days depending on agent 1, 2
• Uncomplicated pyelonephritis: 5-14 days depending on agent 1
• Complicated UTI: 7-14 days 1
• Recurrent UTI acute episodes: ≤7 days 1

Special Populations

Men with UTI:

• Treat for 7-14 days (14 days if prostatitis cannot be excluded) 1
• All UTIs in men are considered complicated 1

Women with Diabetes:

• Treat similarly to women without diabetes if no voiding abnormalities present 2
• Consider as complicated UTI if structural/functional abnormalities exist 1

Pediatric Patients (2-24 months with febrile UTI):

• Oral and parenteral routes are equally efficacious 1
• Treat for 7-14 days 1
• Ceftriaxone 75 mg/kg every 24 hours or cefotaxime 150 mg/kg/day divided every 6-8 hours for parenteral therapy 1
• Amoxicillin-clavulanate 20-40 mg/kg/day in 3 doses or TMP-SMX 6-12 mg/kg trimethoprim with 30-60 mg/kg sulfamethoxazole per day in 2 doses for oral therapy 1

Critical Antimicrobial Stewardship Principles

Combine knowledge of local antibiogram with selection of agents having least impact on vaginal and fecal flora. 1

• Fluoroquinolones and third-generation cephalosporins cause significant "collateral damage" by selecting multidrug-resistant organisms 4
• Reserve fluoroquinolones for pyelonephritis and serious infections 1, 4, 2
• Fosfomycin, nitrofurantoin, and pivmecillinam have minimal collateral damage 4
• Do not use TMP-SMX empirically if local E. coli resistance exceeds 20% 1, 4

Common Pitfalls to Avoid

• Never treat asymptomatic bacteriuria except in pregnant women or before mucosal-traumatizing urinary procedures - treatment increases resistance without clinical benefit 1, 5
• Failing to obtain pre-treatment cultures in recurrent or complicated UTI complicates management of treatment failures 1, 5
• Using fluoroquinolones as first-line for simple cystitis contributes to resistance and collateral damage 1, 4
• Treating for longer than necessary increases resistance risk without improving outcomes 1
• Do not obtain routine post-treatment cultures in asymptomatic patients 5
• Inadequate treatment duration for complicated UTI (less than 7 days) leads to treatment failure 1, 5