What is the treatment for acute simple cystitis (urinary tract infection)?

Treatment of Acute Simple Cystitis

For acute simple cystitis (uncomplicated UTI), first-line treatment options include nitrofurantoin monohydrate/macrocrystals (100 mg twice daily for 5 days), trimethoprim-sulfamethoxazole (160/800 mg twice daily for 3 days, if local E. coli resistance <20%), or fosfomycin trometamol (single 3g dose). 1

First-Line Treatment Options

Nitrofurantoin

• Dosage: 100 mg twice daily for 5 days 1
• Highly effective for most uncomplicated UTIs
• Should be avoided in patients with CrCl <30 ml/min 2
• May cause gastrointestinal side effects; rare cases of systemic inflammatory response syndrome have been reported 3

Trimethoprim-sulfamethoxazole (TMP-SMX)

• Dosage: 160/800 mg (double-strength tablet) twice daily for 3 days 1
• Only recommended if local E. coli resistance is <20% 1
• Clinical cure rates significantly lower (41%) when used for TMP-SMX-resistant organisms 4

Fosfomycin trometamol

• Dosage: Single 3g dose 1, 5
• Convenient single-dose regimen
• FDA-approved specifically for uncomplicated UTIs (acute cystitis) in women 5
• Active against multidrug-resistant pathogens
• May have lower bacterial eradication rates than other first-line agents 1

Antibiotic Stewardship Considerations

• Fluoroquinolones (e.g., levofloxacin) should be reserved for situations where first-line agents cannot be used 1, 6

• Reasons to avoid fluoroquinolones as first-line therapy:

  • Risk of collateral damage to gut microbiota
  • Increased risk of C. difficile infection
  • Need to preserve effectiveness for more serious infections 1

• Beta-lactams (amoxicillin-clavulanate, cefaclor, cefdinir, cefpodoxime) are not recommended as first-line therapy due to:

  • Lower effectiveness compared to first-line options 7, 8
  • Higher rates of resistance
  • Greater impact on gut microbiota 1

Special Populations

Pregnant Women

• Nitrofurantoin (except in late pregnancy) or fosfomycin are preferred options 1

Patients with Diabetes

• Require special attention due to higher risk of complications
• Ensure good glycemic control during treatment 1

Patients with Renal Insufficiency

• Nitrofurantoin is generally effective in patients with CrCl 30-60 ml/min
• Avoid nitrofurantoin if CrCl <30 ml/min 2

Management of Treatment Failure

• If symptoms persist or recur within 2-4 weeks after treatment:
  • Obtain urine culture 7
  • Consider alternative antibiotic based on susceptibility testing
  • If using fosfomycin and treatment fails, select a different agent 5

Common Pitfalls to Avoid

• Using fluoroquinolones as first-line therapy when other options are available
• Prescribing TMP-SMX empirically in areas with high resistance rates (>20%)
• Failing to consider local resistance patterns when selecting therapy
• Extending antibiotic duration unnecessarily
• Not obtaining follow-up cultures in cases of treatment failure
• Overlooking the possibility of complicated UTI requiring different management

Recurrent UTIs

• Non-antimicrobial measures:
  • Increased fluid intake
  • Urinating after intercourse if UTIs are related to sexual activity
• Consider antibiotic prophylaxis if non-antimicrobial measures fail:
  • Nitrofurantoin 50-100 mg daily
  • Trimethoprim 100 mg daily
  • Post-coital single dose when UTIs are related to sexual activity 1