What is the best treatment for recurrent Urinary Tract Infections (UTIs)?

Treatment of Recurrent Urinary Tract Infections

For recurrent UTIs, begin with non-antimicrobial prevention strategies (increased fluid intake, vaginal estrogen in postmenopausal women, immunoactive prophylaxis, methenamine hippurate), and reserve continuous or postcoital antimicrobial prophylaxis for when these measures fail. 1

Diagnosis and Initial Management

• Confirm each recurrent UTI episode with urine culture before initiating treatment 1, 2
• Do not perform surveillance urine testing or treat asymptomatic bacteriuria, as this fosters antimicrobial resistance and increases recurrence 1, 2
• Do not routinely perform extensive workup (cystoscopy, full abdominal ultrasound) in women younger than 40 years without risk factors 1

Acute Episode Treatment

When treating symptomatic episodes, use first-line agents based on local resistance patterns:

• Nitrofurantoin: 50-100 mg four times daily OR 100 mg twice daily for 5 days 1, 2
• Fosfomycin trometamol: 3 g single dose (recommended only in women with uncomplicated cystitis) 1, 2
• Trimethoprim-sulfamethoxazole: 160/800 mg twice daily for 3 days 1, 2

Treat acute episodes with the shortest reasonable duration, generally no longer than 7 days 2. Single-dose therapy increases risk of bacteriological persistence compared to 3-6 day courses 1.

Prevention Strategy Algorithm

Step 1: Non-Antimicrobial Measures (Try First)

• Increase fluid intake to promote more frequent urination 1
• Postmenopausal women: Use vaginal estrogen replacement (strong recommendation) 1 - this is highly effective and should be first-line in this population
• Immunoactive prophylaxis (OM-89/Uro-Vaxom) to reduce recurrence (strong recommendation) 1
• Methenamine hippurate for women without urinary tract abnormalities (strong recommendation) 1, 2
• Consider cranberry products (minimum 36 mg/day proanthocyanidin A), though evidence quality is low with contradictory findings 1
• Consider D-mannose, though evidence is weak and contradictory 1
• Advise probiotics containing Lactobacillus rhamnosus GR-1 or Lactobacillus reuteri RC-14 once or twice weekly 1

Step 2: Antimicrobial Prophylaxis (When Non-Antimicrobial Measures Fail)

Continuous daily prophylaxis for 6-12 months (strong recommendation) 1:

• Nitrofurantoin 50-100 mg daily 1, 3, 4
• Trimethoprim 100 mg daily 1, 3
• Trimethoprim-sulfamethoxazole 40/200 mg daily 1, 3
• Fosfomycin 3 g every 10 days 1

Postcoital prophylaxis (for UTIs temporally related to sexual activity):

• Trimethoprim-sulfamethoxazole 40/200 mg after intercourse 1, 5
• This reduces infection rate from 3.6 to 0.3 per patient-year 5
• Effective for both low (≤2 times/week) and high (≥3 times/week) intercourse frequencies 5

Step 3: Self-Administered Treatment

For patients with good compliance, offer self-administered short-term antimicrobial therapy at symptom onset (strong recommendation) 1, 2. This is the most cost-effective strategy and improves quality-adjusted life-years 6.

Critical Adverse Event Counseling

Before prescribing antimicrobial prophylaxis, discuss these risks:

• Nitrofurantoin: Pulmonary toxicity (0.001% risk) and hepatic toxicity (0.0003% risk), though rates are extremely low 1
• All antibiotics: Gastrointestinal disturbances, skin rash, and risk of selecting resistant pathogens 1, 3
• Prophylaxis effects last only during active intake; recurrence returns to baseline after cessation 1

Common Pitfalls to Avoid

• Do not treat asymptomatic bacteriuria - this is the most common error and increases resistance 1, 2
• Do not use broad-spectrum antibiotics when narrower options are available 2
• Do not classify uncomplicated recurrent UTI as "complicated" - this leads to unnecessary broad-spectrum use 2
• Do not continue antibiotics beyond recommended duration 2
• Do not skip urine culture before treating recurrent episodes 1, 2
• Do not start antimicrobial prophylaxis before attempting non-antimicrobial measures 1, 3

Comparative Effectiveness

Daily nitrofurantoin prophylaxis is most effective, reducing UTI rate from 3/year to 0.4/year, but is most expensive ($821/year to payer) 6. Symptomatic self-treatment provides patient cost savings and is most favorable for cost per quality-adjusted life-year gained 6. All prevention strategies improve quality of life compared to no intervention 6.