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

Treatment of Urinary Tract Infections (UTIs)

For uncomplicated UTIs in adults, first-line treatment options include nitrofurantoin 100mg twice daily for 5 days, trimethoprim-sulfamethoxazole 160/800mg twice daily for 3 days, or fosfomycin 3g as a single dose. 1

Diagnosis Before Treatment

• Obtain a urine specimen for culture prior to initiating antimicrobial therapy to identify the infecting organism and determine antimicrobial resistance 1
• A high colony count (>100,000 cfu/ml) in a urine culture suggests true infection 1
• Differentiate between colonization and true infection before initiating treatment 1

Treatment Algorithm for UTIs

Uncomplicated UTIs in Women

1. First-line options (in order of preference):

   • Nitrofurantoin 100mg twice daily for 5 days (if GFR >30 mL/min)
   • Trimethoprim-sulfamethoxazole 160/800mg twice daily for 3 days (if local resistance <20%)
   • Fosfomycin 3g as a single dose 1, 2

2. Second-line options:

   • Pivmecillinam for 5 days (if susceptibility confirmed)
   • Oral cephalosporins (e.g., cephalexin)
   • Amoxicillin-clavulanate 1, 3

3. Reserve fluoroquinolones (e.g., ciprofloxacin) for more invasive infections due to increasing resistance rates and potential side effects 1, 4

Complicated UTIs

1. Treatment duration: 7-10 days 1
2. Parenteral options for severe infections:
   • Ceftazidime-avibactam
   • Meropenem-vaborbactam
   • Imipenem-cilastatin-relebactam
   • Ceftriaxone 1-2g daily 1, 3

Catheter-Associated UTIs

1. If catheter has been in place ≥2 weeks and is still needed, replace the catheter before collecting specimen and initiating treatment 1
2. Obtain urine culture specimens from freshly placed catheters prior to initiating antimicrobial therapy 1
3. Discontinue urinary catheters as soon as possible 1

Special Populations

Postmenopausal Women with Recurrent UTIs

• Consider vaginal estrogen with or without lactobacillus-containing probiotics 5, 1

Premenopausal Women with Post-Coital Infections

• Consider low-dose antibiotic prophylaxis within 2 hours of sexual activity for 6-12 months 5

Men with UTIs

• Limited evidence supports 7-14 days of therapy 4

Diabetic Women

• Treat similarly to women without diabetes if no voiding abnormalities are present 4

Treatment Monitoring and Follow-up

• Monitor clinical response within 72 hours of initiating therapy 1
• If no improvement occurs, consider:
  • Extending treatment duration
  • Performing urologic evaluation
  • Adjusting antimicrobial regimen based on culture and susceptibility results 1

Prevention of Recurrent UTIs

• Non-antimicrobial measures:
  • Increased fluid intake
  • Postcoital voiding
  • Avoiding prolonged urine retention 1
  • Vaginal estrogen replacement for postmenopausal women
  • Probiotics 1

Common Pitfalls to Avoid

1. Treating asymptomatic bacteriuria: Should not be treated, especially in elderly patients, as this does not improve outcomes and contributes to antibiotic resistance 1

2. Overuse of fluoroquinolones: High rates of resistance preclude their use as empiric treatment in many communities, particularly in patients recently exposed to them or at risk of infections with ESBL-producing bacteria 3

3. Inadequate treatment duration: Too short a course may lead to treatment failure, while unnecessarily long courses contribute to antibiotic resistance 5, 1

4. Failure to narrow antibiotic spectrum: Once culture results are available, therapy should be targeted to the specific organism to reduce the risk of developing resistance 5, 3

5. Not considering local resistance patterns: Treatment should take into account local antibiograms when selecting empiric therapy 5, 4