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

Treatment of Urinary Tract Infections

For uncomplicated UTIs, first-line treatments include nitrofurantoin, trimethoprim-sulfamethoxazole, and fosfomycin, while complicated UTIs require broader spectrum antibiotics with treatment guided by culture results. 1

Uncomplicated UTIs

First-line Treatment Options

• Nitrofurantoin: 100mg twice daily for 5 days
• Trimethoprim-sulfamethoxazole: One double-strength tablet (160mg/800mg) twice daily for 3 days 1, 2
• Fosfomycin: Single 3g dose 1, 3

Important Considerations

• Fluoroquinolones (e.g., ciprofloxacin) should NOT be used empirically for uncomplicated UTIs due to high risk of adverse effects and increasing resistance 1
• Local resistance patterns should guide empiric therapy choice
• Trimethoprim-sulfamethoxazole should be avoided if local resistance exceeds 20% or if the patient has used this antibiotic in the past 3 months 4
• Patients with resistant organisms experience longer symptom duration (7 vs 4 days) and higher reconsultation rates (39% vs 6%) 5

Complicated UTIs

Definition and Approach

Complicated UTIs include:

• UTIs in males
• Pyelonephritis
• UTIs with structural/functional abnormalities
• Catheter-associated UTIs
• UTIs in pregnancy or immunocompromised patients

Management Steps

1. Obtain urine culture before starting antibiotics 1
2. Initial empiric therapy options:
   • Ciprofloxacin (if local resistance patterns allow) for pyelonephritis and prostatitis 1
   • IV options for severe cases: meropenem, ceftazidime-avibactam, piperacillin-tazobactam 4
3. Adjust therapy based on culture results
4. Longer treatment duration: 7-14 days depending on severity and organism

Special Populations

Renal Impairment

Dosage adjustments required based on creatinine clearance:

• For example, levofloxacin dosing:
  • CrCl ≥50 mL/min: 500 mg once daily
  • CrCl 26-49 mL/min: 500 mg once daily
  • CrCl 10-25 mL/min: 250 mg once daily 1

Pediatric Patients

• Avoid fluoroquinolones due to risk of tendinopathy 1
• For infants 29-60 days: ceftriaxone 50 mg/kg IV/IM once daily 1

Pregnant Women

• Nitrofurantoin (avoid in 3rd trimester)
• Cephalexin
• Amoxicillin-clavulanate
• Avoid trimethoprim in first trimester 1

Prevention of Recurrent UTIs

Non-pharmacological Measures

• Increase fluid intake (strong evidence) 1
• Void after sexual intercourse 1
• Avoid prolonged urine retention 1
• Avoid harsh vaginal cleansers and spermicides 1

Pharmacological Prevention

• Vaginal estrogen for postmenopausal women (strongly recommended) 1
• Prophylactic antibiotics options:
  • Trimethoprim-sulfamethoxazole
  • Nitrofurantoin
  • Cephalexin
  • Fosfomycin 1

Common Pitfalls to Avoid

1. Treating asymptomatic bacteriuria: Should not be treated in most populations including those with diabetes, older adults with functional/cognitive impairment, and catheterized patients 1

2. Overuse of fluoroquinolones: Reserve for complicated UTIs when susceptibility is known 1

3. Failure to adjust antibiotics for renal function: Can lead to toxicity, especially with aminoglycosides 1

4. Inadequate follow-up: No routine post-treatment urinalysis or cultures needed for asymptomatic patients 1

5. Inappropriate antibiotic duration: Uncomplicated UTIs require only 3-5 days of therapy; longer courses increase resistance risk 1, 4

6. Ignoring local resistance patterns: E. coli remains the predominant uropathogen, but resistance patterns vary by region 6