What are the recommended treatments for uncomplicated and complicated urinary tract infections (UTIs)?

Treatment of Urinary Tract Infections (UTIs)

First-Line Treatment for Uncomplicated Cystitis in Women

For uncomplicated cystitis in women, the recommended first-line treatments are fosfomycin trometamol (3g single dose), nitrofurantoin (100mg twice daily for 5 days), or pivmecillinam (400mg three times daily for 3-5 days). 1, 2

• Fosfomycin trometamol is effective as a single 3g dose for uncomplicated cystitis, offering convenience with minimal resistance and low propensity for collateral damage 1, 2
• Nitrofurantoin macrocrystals can be prescribed as 50-100mg four times daily or 100mg twice daily for 5 days 1, 2
• Pivmecillinam is effective at 400mg three times daily for 3-5 days where available (primarily in European countries) 1

Alternative Treatments When First-Line Options Cannot Be Used

• Trimethoprim-sulfamethoxazole (160/800mg twice daily for 3 days) is appropriate if local resistance rates do not exceed 20% or if the infecting strain is known to be susceptible 1
• Cephalosporins (e.g., cefadroxil 500mg twice daily for 3 days) can be used if local E. coli resistance is <20% 1, 2
• Fluoroquinolones (e.g., ciprofloxacin, levofloxacin) are highly efficacious but should be reserved for more important uses due to their propensity for collateral damage 1, 3
• β-lactams (except pivmecillinam) generally have inferior efficacy and more adverse effects compared to other UTI antimicrobials 1, 4

Treatment for Complicated UTIs and Pyelonephritis

Acute Pyelonephritis in Outpatients

• Oral ciprofloxacin (500mg twice daily) for 7 days is appropriate for outpatient treatment where fluoroquinolone resistance is <10% 1
• Once-daily oral fluoroquinolones like levofloxacin (750mg for 5 days) are also appropriate options 1, 3
• If fluoroquinolone resistance exceeds 10%, an initial IV dose of a long-acting parenteral antimicrobial (e.g., ceftriaxone 1g) is recommended before oral therapy 1
• Oral trimethoprim-sulfamethoxazole (160/800mg twice daily for 14 days) is appropriate if the pathogen is known to be susceptible 1

Hospitalized Patients with Pyelonephritis

• Initial IV antimicrobial regimens may include: fluoroquinolones, aminoglycosides (with or without ampicillin), extended-spectrum cephalosporins, extended-spectrum penicillins, or carbapenems 1
• Treatment should be based on local resistance patterns and tailored according to susceptibility results 1

Treatment in Men

• Trimethoprim-sulfamethoxazole (160/800mg twice daily for 7 days) is recommended for UTIs in men 1, 5
• Fluoroquinolones can be prescribed according to local susceptibility testing 1, 5
• Men with UTI symptoms should always receive antibiotics, with treatment guided by urine culture and susceptibility results 5
• Consider the possibility of urethritis and prostatitis in men with UTI symptoms 5

Special Considerations

Diagnostic Approach

• Diagnosis of uncomplicated cystitis can be made with high probability based on lower urinary tract symptoms (dysuria, frequency, urgency) and absence of vaginal discharge 1, 5
• Urine culture is recommended for:
  • Suspected acute pyelonephritis
  • Symptoms that don't resolve or recur within 4 weeks after treatment
  • Women with atypical symptoms
  • Pregnant women
  • Men with UTI symptoms 1, 5

Recurrent UTIs

• For women with recurrent UTIs, always perform a urine culture for diagnosis 1
• Consider prophylaxis when non-antimicrobial interventions have failed 2, 6
• In postmenopausal women, consider vaginal estrogen replacement to prevent recurrent UTIs 2

Antimicrobial Resistance Considerations

• Local antimicrobial susceptibility patterns should guide empirical therapy 1, 7
• E. coli is the predominant pathogen (75-95%) in uncomplicated UTIs 1, 4
• Nitrofurantoin, fosfomycin, and pivmecillinam generally maintain good activity against resistant pathogens 1, 4, 6
• Resistance rates >20% have been reported for ampicillin and trimethoprim/sulfamethoxazole in many regions 1, 7

Treatment Algorithm

1. For uncomplicated cystitis in women:

   • First-line: Fosfomycin 3g single dose, nitrofurantoin 100mg BID for 5 days, or pivmecillinam 400mg TID for 3-5 days 1, 2
   • Alternative: Trimethoprim-sulfamethoxazole 160/800mg BID for 3 days (if local resistance <20%) 1, 7

2. For men with UTI:

   • Trimethoprim-sulfamethoxazole 160/800mg BID for 7 days or fluoroquinolones based on susceptibility 1, 5

3. For pyelonephritis (outpatient):

   • Ciprofloxacin 500mg BID for 7 days or levofloxacin 750mg daily for 5 days (if resistance <10%) 1, 3
   • If resistance >10%: Initial IV ceftriaxone 1g, then oral therapy based on susceptibility 1

4. For hospitalized patients with complicated UTIs:

   • IV therapy with fluoroquinolones, aminoglycosides, extended-spectrum cephalosporins/penicillins, or carbapenems 1
   • Tailor therapy based on culture results 1