What is the recommended treatment for acute cystitis?

Treatment of Acute Cystitis

For acute uncomplicated cystitis in women, nitrofurantoin monohydrate/macrocrystals 100 mg twice daily for 5 days is the preferred first-line treatment, offering optimal efficacy with minimal resistance and collateral damage to normal flora. 1

First-Line Treatment Options

The choice of antibiotic depends on local resistance patterns, patient allergies, and renal function:

Preferred First-Line Agents

• Nitrofurantoin monohydrate/macrocrystals 100 mg twice daily for 5 days is the gold standard for uncomplicated cystitis, with clinical cure rates of 90% and minimal resistance development 2, 1, 3

• Fosfomycin trometamol 3 g as a single oral dose provides convenient single-dose therapy with clinical cure rates of 90-91%, though it may have slightly inferior efficacy compared to multi-day regimens 4, 1, 3

• Pivmecillinam 400 mg three times daily for 3-5 days is recommended in European countries where available 1

Conditional First-Line Agent

• Trimethoprim-sulfamethoxazole 160/800 mg twice daily for 3 days can be used ONLY if local E. coli resistance rates are below 20% or if the specific isolate is known to be susceptible 2, 1, 3
  • Rising resistance rates have significantly limited its utility as empiric therapy 2
  • Clinical cure rates of 82-100% when the organism is susceptible 2

Second-Line Treatment Options (When First-Line Agents Cannot Be Used)

β-Lactam Antibiotics (Use with Caution)

• Amoxicillin-clavulanate, cefdinir, cefaclor, or cefpodoxime-proxetil for 3-7 days are appropriate when other agents cannot be used, but they have inferior efficacy and more adverse effects compared to first-line agents 2, 1

• Cephalexin is less well studied but may be appropriate in certain settings 2

Fluoroquinolones (Reserve for More Serious Infections)

• Ciprofloxacin or levofloxacin should be reserved for situations where first-line agents cannot be used due to concerns about promoting resistance to these important agents needed for more serious infections 1, 3

Antibiotics to AVOID for Empiric Treatment

• Amoxicillin or ampicillin should NOT be used empirically due to poor efficacy and very high prevalence of antimicrobial resistance worldwide 2, 1

Special Populations

Patients with Chronic Kidney Disease (CKD)

Treatment algorithm based on renal function:

• If eGFR >30 mL/min: Nitrofurantoin 100 mg twice daily for 5 days 4

• If eGFR <30 mL/min: Fosfomycin trometamol 3 g single dose (nitrofurantoin should be avoided due to reduced efficacy and increased toxicity risk) 4

• Urine culture with susceptibility testing is strongly recommended before initiating therapy in CKD patients 4

Patients with Penicillin and Sulfa Allergies

• First choice: Nitrofurantoin 100 mg twice daily for 5 days (if eGFR >30 mL/min) 4

• If nitrofurantoin contraindicated: Fosfomycin trometamol 3 g single dose 4

• Avoid cephalosporins in patients with documented penicillin allergy without formal allergy testing due to cross-reactivity concerns 4

Women with Diabetes

• Treat similarly to women without diabetes if there are no voiding abnormalities, using the same first-line agents for 5-7 days 3

Men with Acute Cystitis

• Treatment duration should be 7-14 days (longer than in women) using the same first-line agents 3

Diagnostic Considerations

• Urinalysis is recommended for diagnosis, but urine culture is NOT routinely needed for uncomplicated cystitis 3, 5

• Urine culture with susceptibility testing should be performed if:

  • Symptoms do not resolve by the end of treatment 1
  • Symptoms recur within 2-4 weeks after completing treatment 1, 5
  • Patient presents with atypical symptoms 5
  • Patient has CKD or other complicating factors 4

Treatment Algorithm for Uncomplicated Cystitis

1. Confirm diagnosis: Frequency, dysuria, suprapubic tenderness in immunocompetent woman without comorbidities 5

2. First choice: Nitrofurantoin 100 mg twice daily for 5 days 1

3. If nitrofurantoin contraindicated: Fosfomycin 3 g single dose 1

4. If local TMP-SMX resistance <20%: Consider TMP-SMX 160/800 mg twice daily for 3 days 1

5. If all first-line options unavailable: Consider β-lactams (3-7 days) or fluoroquinolones, recognizing their limitations 1

6. Immediate antimicrobial therapy is recommended rather than delayed treatment or symptom management with ibuprofen alone 3

Common Pitfalls to Avoid

• Do NOT use fluoroquinolones as first-line therapy despite their high efficacy, as this promotes resistance to agents needed for more serious infections 1

• Do NOT prescribe TMP-SMX empirically without knowledge of local resistance patterns (must be <20% resistance) 1

• Do NOT use amoxicillin or ampicillin empirically due to high resistance rates 1

• Do NOT use nitrofurantoin in patients with eGFR <30 mL/min, as this leads to treatment failure and increased toxicity 4

• Do NOT fail to adjust therapy if symptoms persist, which may indicate resistance to the chosen antibiotic 1

• Do NOT fail to obtain urine cultures in complicated UTIs or in patients with CKD 4, 6