What is the first-line treatment for cystitis in women?

First-Line Treatment for Cystitis in Women

Nitrofurantoin (100 mg twice daily for 5 days) is the first-line treatment for uncomplicated cystitis in women due to its minimal resistance and limited collateral damage, with efficacy comparable to trimethoprim-sulfamethoxazole. 1

Treatment Algorithm for Uncomplicated Cystitis in Women

First-Line Options (in order of preference):

1. Nitrofurantoin monohydrate/macrocrystals

   • Dosage: 100 mg twice daily
   • Duration: 5 days
   • Advantages: Minimal resistance, limited collateral damage
   • Contraindication: Avoid if CrCl <30 mL/min

2. Trimethoprim-sulfamethoxazole (TMP-SMX)

   • Dosage: 160/800 mg (double-strength tablet) twice daily
   • Duration: 3 days
   • Use only when local E. coli resistance rates <20%
   • Avoid in first and third trimesters of pregnancy

3. Fosfomycin trometamol

   • Dosage: 3 g single dose
   • Advantages: Minimal resistance, convenient single-dose regimen
   • Note: May have slightly lower efficacy than other first-line options 1, 2

Alternative Options (when first-line agents cannot be used):

1. Fluoroquinolones (ciprofloxacin, levofloxacin)

   • Duration: 3-day regimen
   • Note: Should be reserved for situations where first-line agents cannot be used due to concerns about collateral damage and resistance 1
   • Contraindicated in pregnancy

2. β-lactams (amoxicillin-clavulanate, cefdinir, cefaclor, cefpodoxime-proxetil)

   • Duration: 3-7 days
   • Note: Generally have inferior efficacy and more adverse effects compared to first-line options 1

Diagnostic Approach

For women with typical symptoms of uncomplicated cystitis (dysuria, frequency, urgency):

• Diagnosis can be made based on symptoms alone
• Urine dipstick testing can increase diagnostic accuracy if diagnosis is unclear
• Urine culture is NOT routinely needed for uncomplicated cases 1

Obtain urine culture in these specific situations:

• Suspected pyelonephritis
• Symptoms that don't resolve or recur within 2-4 weeks after treatment
• Women with atypical symptoms
• Pregnant women 3

Important Considerations

1. Local Resistance Patterns: When selecting TMP-SMX, consider local E. coli resistance rates. If >20%, choose nitrofurantoin or fosfomycin instead 1

2. Pregnancy Considerations: For pregnant women, preferred options include nitrofurantoin, amoxicillin-clavulanate, or cephalosporins. Avoid TMP-SMX in first and third trimesters and fluoroquinolones throughout pregnancy 4

3. Treatment Failure: For women whose symptoms don't resolve by end of treatment or recur within 2 weeks, perform urine culture with susceptibility testing and select an alternative agent 1

4. Avoid Inappropriate Antibiotics: Amoxicillin or ampicillin should not be used for empirical treatment due to poor efficacy and high resistance rates 1

5. Post-Treatment Follow-up: Routine post-treatment urinalysis or urine cultures are not indicated for asymptomatic patients 1

Pitfalls to Avoid

1. Using fluoroquinolones as first-line therapy when other options are available (increases risk of resistance and collateral damage)

2. Treating asymptomatic bacteriuria (except in pregnancy)

3. Prescribing prolonged treatment courses (>7 days) which don't improve outcomes but increase adverse effects

4. Failing to obtain urine culture when symptoms persist or recur shortly after treatment

5. Using broad-spectrum antibiotics unnecessarily, which increases risk of C. difficile infection and antimicrobial resistance

By following this evidence-based approach to treating uncomplicated cystitis in women, you can provide effective treatment while minimizing antibiotic resistance and adverse effects.