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

Treatment of Recurrent Urinary Tract Infections

Treatment of recurrent UTIs requires a population-specific algorithmic approach that prioritizes non-antibiotic strategies first, followed by targeted antibiotic prophylaxis based on menopausal status and infection pattern, with the goal of reducing recurrence while minimizing antimicrobial resistance.

Definition and Diagnosis

• Recurrent UTI is defined as ≥2 culture-positive UTIs in 6 months or ≥3 in one year 1, 2
• Obtain urine culture with each symptomatic episode before initiating treatment to document infection and guide antibiotic selection 2, 3
• Extensive workup (cystoscopy, abdominal ultrasound) is not recommended for women younger than 40 without risk factors 2

Initial Management: Behavioral and Lifestyle Modifications

Start with these evidence-based interventions before considering pharmacologic prophylaxis 1:

• Increase fluid intake throughout the day to maintain adequate hydration 2, 3
• Void after intercourse to reduce bacterial inoculation 2, 3
• Avoid prolonged holding of urine 2
• Avoid disruption of normal vaginal flora with harsh cleansers or spermicides 2

Population-Specific Treatment Algorithm

Postmenopausal Women

First-line approach:

• Vaginal estrogen replacement therapy is strongly recommended as the most effective prevention strategy in this population 1, 2, 3
• Can be combined with lactobacillus-containing probiotics for additional benefit 1

Premenopausal Women with Sexually-Associated Infections

• Low-dose post-coital antibiotics are recommended as first-line prophylaxis 1, 2
• Should be taken within 2 hours of sexual activity 4

Premenopausal Women with Non-Sexually-Associated Infections

• Low-dose daily antibiotic prophylaxis is recommended when non-antimicrobial measures fail 1, 2

Non-Antibiotic Prophylaxis Options

When antibiotic prophylaxis is not desired or appropriate, consider these alternatives in order of evidence strength:

Strong evidence:

• Methenamine hippurate is strongly recommended for women without urinary tract abnormalities 1, 2, 3, 4

Moderate evidence:

• Immunoactive prophylaxis (OM-89) to reduce recurrence episodes 2, 4
• Probiotics containing specific lactobacillus strains with proven efficacy for vaginal flora regeneration 1, 2

Weak/contradictory evidence:

• Cranberry products (minimum 36 mg/day proanthocyanidin A if used) 2, 3, 4
• D-mannose 2, 3, 4

Antibiotic Treatment for Acute Episodes

First-line options for uncomplicated cystitis:

• Nitrofurantoin 100 mg twice daily for 5 days 2, 3
• Fosfomycin trometamol 3 g single dose 2, 3
• Trimethoprim-sulfamethoxazole 160/800 mg twice daily for 3 days (only if local resistance <20%) 2, 3, 5

Key principle: Use prior culture data to guide empiric antibiotic selection for subsequent episodes 2

Antibiotic Prophylaxis Regimens

When continuous prophylaxis is indicated after non-antimicrobial measures have failed 1, 4:

• Nitrofurantoin 50-100 mg daily (preferred due to low resistance rates) 3, 6, 7
• Trimethoprim-sulfamethoxazole (alternative option) 4, 6, 7
• Trimethoprim alone (alternative option) 4

Important consideration: Nitrofurantoin is preferred because resistance is low and decays quickly if it develops 3

Critical Pitfalls to Avoid

• Never treat asymptomatic bacteriuria as this increases antimicrobial resistance and recurrence rates 2, 3, 4
• Do not classify recurrent UTIs as "complicated" solely based on recurrence, as this leads to unnecessary broad-spectrum antibiotic use 2, 3, 4
• Avoid fluoroquinolones due to high resistance rates and serious adverse effects 3
• Do not use prolonged antibiotic courses (>5 days) for acute episodes 4
• If symptoms persist despite treatment, repeat urine culture before prescribing additional antibiotics 2, 3, 4

Monitoring and Follow-up

• Document response to prophylactic strategies 2
• Consider rotating antibiotics at 3-month intervals to avoid selection of antimicrobial resistance 2
• If prophylactic measures fail, consider endovesical instillations of hyaluronic acid or combination therapy 2
• Continuous antibiotic prophylaxis reduces UTI episodes, emergency room visits, and hospital admissions by approximately 90% when properly indicated 6, 7

Special Populations

Women with breast cancer on aromatase inhibitors (e.g., exemestane):

• Vaginal estrogen therapy is contraindicated 4
• Prioritize methenamine hippurate, immunoactive prophylaxis, or antibiotic prophylaxis 4

Patients with urinary catheters or complicating urological factors:

• Success depends on eliminating or improving the complicating risk factors 6
• Reduce frequency and duration of catheter drainage when possible 6