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

Treatment of Urinary Tract Infections (UTIs)

For uncomplicated UTIs, first-line treatment options include nitrofurantoin for 5 days, trimethoprim-sulfamethoxazole for 3 days (if local resistance is <20%), or fosfomycin as a single dose. 1

Classification of UTIs

UTIs are classified based on:

• Location: Lower (cystitis) vs. Upper (pyelonephritis)
• Complexity: Uncomplicated vs. Complicated
• Pattern: Acute vs. Recurrent

Treatment Algorithm

Uncomplicated Lower UTI (Cystitis)

1. First-line options:

   • Nitrofurantoin 100mg BID for 5 days
   • Trimethoprim-sulfamethoxazole DS BID for 3 days (if local resistance <20%)
   • Fosfomycin 3g single dose

2. Second-line options:

   • Cephalexin or other oral cephalosporins
   • Amoxicillin-clavulanate
   • Fluoroquinolones (should be reserved due to resistance concerns and adverse effects) 1, 2

Complicated UTI and Pyelonephritis

1. Mild to moderate pyelonephritis:

   • Ciprofloxacin (if local resistance patterns allow) 1

2. Severe or complicated infections:

   • Meropenem 1g IV q8h (7-14 days depending on severity)
   • Other parenteral options based on susceptibility 1

3. Important steps:

   • Obtain urine culture before starting antibiotics
   • Adjust therapy based on susceptibility results 1

Special Populations

Pediatric Patients

• For children 29-60 days: Ceftriaxone 50 mg/kg IV/IM once daily
• Fluoroquinolones should be avoided due to risk of tendinopathy 1
• Ciprofloxacin is not a first-choice drug in pediatric populations due to increased adverse events related to joints/tissues 3

Postmenopausal Women

• Consider vaginal estrogen replacement for prevention of recurrent UTIs 1

Patients with Renal Impairment

Dosage adjustments required:

• 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

Antibiotic Resistance Considerations

• ESBL-producing organisms: Treatment options include nitrofurantoin, fosfomycin, pivmecillinam, and carbapenems 2, 4
• AmpC β-lactamase producers: Options include nitrofurantoin, fosfomycin, fluoroquinolones, cefepime, piperacillin-tazobactam, and carbapenems 2, 4
• Carbapenem-resistant Enterobacteriaceae: Limited options include ceftazidime-avibactam, colistin, fosfomycin, and aminoglycosides 2, 4

Prevention of Recurrent UTIs

• Increase fluid intake
• Void after sexual intercourse
• Avoid prolonged urine retention
• Avoid harsh cleansers that disrupt vaginal flora
• Consider prophylactic antibiotics (trimethoprim-sulfamethoxazole, nitrofurantoin, cephalexin, or fosfomycin) 1

Important Caveats

• Avoid treating asymptomatic bacteriuria in most patient populations (except pregnant women and those undergoing urologic procedures) 1
• Fluoroquinolones should not be used empirically due to high rates of adverse effects and increasing resistance 1, 2
• Aminoglycosides carry high risk of nephrotoxicity and ototoxicity and should be avoided unless no alternatives exist 1
• No routine post-treatment testing is needed for asymptomatic patients 1
• Local resistance patterns should guide empiric therapy choices 1, 5

By following these evidence-based recommendations, clinicians can effectively treat UTIs while practicing good antibiotic stewardship to limit the development of further resistance.