Reducing Risk of Recurrent Cystitis
For postmenopausal women, vaginal estrogen replacement is the foundation of prevention, reducing recurrence by 75%, while premenopausal women should use post-coital or continuous low-dose antibiotic prophylaxis when behavioral modifications fail. 1
Algorithmic Approach by Patient Population
Postmenopausal Women (First-Line Strategy)
Vaginal estrogen is the most effective non-antimicrobial intervention with strong evidence. 1 Start with estriol cream 0.5 mg intravaginally, ensuring weekly doses of ≥850 µg for optimal efficacy. 1 This normalizes vaginal flora, reduces recurrent UTIs, and improves dysuria, frequency, and urgency. 2
- If recurrences persist despite estrogen, add methenamine hippurate 1 gram twice daily. 2, 1 This is strongly recommended for women without urinary tract abnormalities. 3, 2
- Consider adding lactobacillus-containing probiotics to vaginal estrogen for additional benefit. 1
- Implement continuous or postcoital antimicrobial prophylaxis only if recurrent UTIs persist despite non-antimicrobial measures, with nitrofurantoin 50-100 mg daily preferred due to low resistance rates. 2
Premenopausal Women with Coitus-Related UTIs
Post-coital antibiotics are the primary prevention strategy. 1 Use trimethoprim-sulfamethoxazole 160/800 mg as a single dose after intercourse as first-line. 1 Alternative is nitrofurantoin 50-100 mg post-coitally if local resistance patterns favor it. 1
- Educate patients about the association between recurrent UTI and frequency of sexual intercourse and spermicide use. 4
- Avoid spermicide-containing products, as spermicide use with or without a contraceptive diaphragm is implicated as a risk factor for recurrent UTI. 3
Premenopausal Women with Non-Coital UTIs
Implement low-dose daily antibiotic prophylaxis. 1 Nitrofurantoin 50-100 mg daily is the preferred agent due to low resistance rates. 1
- Seven of eight placebo-controlled studies showed significant reduction in recurrent UTIs with antibiotic prophylaxis. 3
- Continuous antibiotic prophylaxis for 6-12 months reduced UTI rate with a number needed to treat of 1.85. 3
Universal Behavioral and Lifestyle Modifications (All Patients)
Increase fluid intake to 1.5-2 liters daily to mechanically flush bacteria from the urinary tract. 1 This may reduce the risk of recurrent UTI in premenopausal women. 3
- Establish regular toileting schedules and avoid prolonged holding of urine. 1
- Void after intercourse. 3
- Avoid sequential anal and vaginal intercourse. 3
- Control blood glucose in patients with diabetes. 3
- Avoid disruption of normal vaginal microbiota with harsh cleansers. 3
Non-Antimicrobial Alternatives (When Antibiotics Should Be Avoided)
Methenamine hippurate 1 gram twice daily is strongly recommended for women without urinary tract abnormalities. 3, 2, 1 Short-term methenamine hippurate may be effective in preventing UTI with a relative risk of 0.24 in patients without renal tract abnormalities. 3
- Immunoactive prophylaxis (OM-89/Uro-Vaxom) is strongly recommended to reduce recurrent UTI in all age groups. 3, 1
- Cranberry products have weak and contradictory evidence, but patients may be advised on their use with the caveat that evidence quality is low. 3
- D-mannose may reduce recurrent UTI episodes, but evidence is overall weak and contradictory. 3
- Endovesical instillations of hyaluronic acid or combination with chondroitin sulfate can be used when less invasive approaches have failed, though further studies are needed. 3
Antibiotic Prophylaxis Regimens (When Non-Antimicrobial Measures Fail)
Continuous or postcoital antimicrobial prophylaxis should be used when non-antimicrobial interventions have failed. 3 Counsel patients regarding possible side effects. 3
Continuous Daily Prophylaxis Options:
- Nitrofurantoin 50-100 mg daily (preferred due to low resistance rates) 2
- Trimethoprim-sulfamethoxazole 160/800 mg daily 3
- Trimethoprim 200 mg daily 3
Post-Coital Prophylaxis Options:
For patients with good compliance, self-administered short-term antimicrobial therapy should be considered. 3 The strategy that results in the lowest antibiotic exposure is a short course of antibiotics for each episode, initiated as soon as clinical symptoms appear. 5
Diagnostic Confirmation Requirements
Diagnose recurrent UTI via urine culture. 3 Document positive urine cultures associated with each symptomatic episode to confirm the diagnosis. 2 Obtain urinalysis and urine culture with sensitivity for each symptomatic acute cystitis episode. 6
- Do not perform routine cystoscopy or extensive workup (full abdominal ultrasound) in women younger than 40 years with recurrent UTI and no risk factors. 3, 2
- Cystoscopy is not indicated for uncomplicated recurrent UTIs in otherwise healthy women without hematuria, anatomic abnormalities, or treatment failure. 2
Critical Pitfalls to Avoid
Do not treat asymptomatic bacteriuria, which increases antimicrobial resistance without improving outcomes. 2 Treatment of asymptomatic bacteriuria increases the risk of symptomatic infection and bacterial resistance as well as healthcare costs. 3
- Do not use broad-spectrum antibiotics when narrower options are available. 2
- Avoid prolonged antibiotic courses (more than 5 days) or unnecessary antibiotics, as these may be associated with more recurrences due to loss of protective periurethral and vaginal microbiota. 3
- Tailor treatment to the shortest effective duration to mitigate increasing antibiotic resistance. 6
Special Considerations for Men
All UTIs in men are considered complicated and require more extensive evaluation than in women. 6, 1 Evaluate for urinary tract obstruction at any site, foreign bodies (catheters, stents), incomplete bladder emptying with post-void residual measurement, vesicoureteral reflux, and recent urinary tract instrumentation. 6, 1