What is the recommended treatment for urinary tract infections (UTIs)?

Treatment of Urinary Tract Infections (UTIs)

For uncomplicated UTIs in otherwise healthy adult non-pregnant females, the first-line empiric treatment is a 5-day course of nitrofurantoin, a single 3g dose of fosfomycin tromethamine, or a 5-day course of trimethoprim-sulfamethoxazole (when local resistance is <20%). 1, 2

Diagnostic Approach

• Diagnosis requires both symptoms and laboratory confirmation:
  • Symptoms: dysuria, frequency, urgency, costovertebral angle pain, fever (>37.8°C)
  • Laboratory: pyuria (≥10 WBC/mm³) and positive urine culture (>100,000 organisms/mL) 1
• Single organism infection is typical; multiple organisms suggest contamination 1

Treatment Algorithm for UTIs

1. Uncomplicated Cystitis in Non-Pregnant Women

• First-line options (in order of preference):

  • Nitrofurantoin 100mg twice daily for 5 days
  • Fosfomycin tromethamine 3g single dose
  • Trimethoprim-sulfamethoxazole (TMP-SMX) for 3 days (if local resistance <20%) 1, 3

• Second-line options:

  • Oral cephalosporins (cephalexin, cefixime)
  • Amoxicillin-clavulanate
  • Fluoroquinolones (only if susceptibility confirmed by culture due to resistance concerns and safety issues) 1, 2

2. Complicated UTIs

• Consider parenteral therapy initially for severe cases
• Tailor antibiotics based on culture results
• Longer treatment duration (7-14 days)
• Address underlying anatomical or functional abnormalities 1, 2

3. Special Populations

Pregnant Women

• Screen all pregnant women for bacteriuria at ~16 weeks gestation
• Avoid fluoroquinolones and nitrofurantoin near term
• Appropriate beta-lactams preferred
• Consider prophylactic antibiotics for recurrent UTIs 1

Elderly Patients

• Avoid fluoroquinolones in patients with renal impairment
• Do not treat asymptomatic bacteriuria in elderly with incontinence 1

Diabetic Patients

• Emphasize glycemic control
• Consider vaginal estrogen for postmenopausal diabetic women with recurrent UTIs 1

Management of Antibiotic-Resistant UTIs

ESBL-Producing Organisms

• Oral options: nitrofurantoin, fosfomycin, pivmecillinam 1, 2
• Parenteral options (if needed): carbapenems, ceftazidime-avibactam, aminoglycosides 2

Prevention of Recurrent UTIs

• Adequate hydration and proper hygiene
• Consider urologic evaluation for structural abnormalities
• For postmenopausal women: vaginal estrogen (reduces UTI risk by 30-50%) 1
• Consider cranberry products or methenamine hippurate in select cases 1

Important Caveats and Pitfalls

1. Avoid treating asymptomatic bacteriuria except in pregnancy and before urologic procedures 1

2. Fluoroquinolone cautions:

   • Use only when other options not suitable due to serious safety concerns (tendon, muscle, joint, nerve damage)
   • Adjust dosing based on renal function:
     • CrCl ≥50 mL/min: standard dosing
     • CrCl 26-49 mL/min: 500 mg once daily (levofloxacin)
     • CrCl 10-25 mL/min: 250 mg once daily (levofloxacin) 1

3. Antimicrobial stewardship:

   • Use antibiotics only for proven or strongly suspected bacterial infections
   • Consider local resistance patterns when selecting empiric therapy
   • Use culture results to guide therapy when available 4, 2

4. Misdiagnosis risk: Avoid diagnosing UTI based solely on positive urine culture without symptoms, which can lead to unnecessary antibiotic use 1, 3