Recurrent Cystitis

Recurrent cystitis is defined as at least 2 culture proven urinary tract infections in 6 months or at least 3 in 12 months.

• Common in women: about 25 to 30 percent of women with an initial infection have a recurrence within 6 months; about 3 percent experience recurrent episodes.
• Most recurrences are reinfections (different organism or same organism after documented clearance), not relapses; relapse (same organism within 2 weeks of treatment) suggests a persistent focus (stone, structural abnormality, chronic prostatitis, bacterial reservoir in the bladder wall).
• Risk factors: frequent sexual intercourse, new partner, spermicide use, delayed or incomplete voiding, postmenopausal oestrogen deficiency, diabetes (especially with glycosuria, such as with sodium glucose cotransporter 2 inhibitors), pelvic organ prolapse, incontinence, catheter use, anatomical abnormality (urethral diverticulum, vesicovaginal fistula), neurogenic bladder, stones, family history, non-secretor blood group.
• Complications: pyelonephritis, renal scarring (rare in adults), antibiotic resistance, impaired quality of life.

• Repeated episodes of dysuria, frequency, urgency and suprapubic pain, often similar to prior episodes, with interval freedom of symptoms.
• Ask about triggers (intercourse, hygiene, contraception), voiding pattern, post-void residual symptoms, incontinence, postmenopausal vaginal dryness, constipation, fluid intake, prior antibiotic courses, haematuria, loin pain, stones.
• Red flags: visible haematuria between episodes, age over 40 with persistent microscopic haematuria, recurrent infection with the same organism (relapse), pneumaturia or faecaluria (fistula), stones, upper tract involvement, residual volume suggesting retention, neurological disease, voiding difficulty, pelvic mass.
• Examination: abdominal palpation and bladder, pelvic examination for prolapse, atrophic vaginitis and urethral abnormality, neurological screen if indicated, blood pressure.

• Culture each symptomatic episode before treatment to document organisms and sensitivities.
• Baseline: urea and creatinine, eGFR, glucose or HbA1c, full blood count.
• Renal tract ultrasound with post-void residual measurement: indicated for relapse, haematuria, pyelonephritis, men, stones, poor stream or suspected residual. Routine imaging in uncomplicated young women with reinfection pattern is not required.
• Flexible cystoscopy and CT urography if persistent microscopic haematuria, visible haematuria, relapse with same organism, suspected structural abnormality, or pelvic pain not explained.
• Urodynamics when voiding dysfunction or neurogenic bladder is suspected.
• Differentials: interstitial cystitis (bladder pain syndrome), urethral syndrome, overactive bladder, atrophic vaginitis, vulvovaginal conditions, bladder tumour, urolithiasis.

• Non-pharmacological measures:
  • Increase fluid intake to 1.5 to 2 litres daily (premenopausal women drinking 1.5 litres of extra water per day had about half as many episodes).
  • Post-coital voiding, avoid spermicides and diaphragms, wipe front to back, avoid douching and irritant soaps, timed voiding every 3 to 4 hours, treat constipation, avoid tight synthetic clothing.
  • Cranberry products: proanthocyanidin (PAC) 36 mg daily (for example capsules of 500 mg cranberry extract) or 240 mL juice twice daily; modest reduction of about 25 percent in recurrence; avoid in those on warfarin (potential increase in INR) and with oxalate stones.
  • D-mannose 2 g orally once daily or 1 g twice daily (evidence mixed; avoid in diabetes unless monitored).
• Postmenopausal women: vaginal oestrogen reduces recurrence by about 50 percent: estriol 0.5 mg pessary or estradiol 10 microgram vaginal tablet nightly for 2 weeks, then twice weekly for at least 12 months; or estriol 0.1 percent cream 0.5 g (one applicator) nightly for 2 weeks then twice weekly. Systemic hormone therapy alone does not prevent recurrence.
• Methenamine hippurate 1 g orally twice daily (prophylaxis; the urine must be acidic with pH below 6; avoid in severe hepatic impairment, severe renal impairment with eGFR under 10 to 30 mL/min depending on label, gout, metabolic acidosis, and concurrent sulfonamides). Randomised comparison shows no meaningful difference from low dose antibiotic prophylaxis in women with recurrent infection. Use for 6 to 12 months.
• Immunoactive prophylaxis: OM-89 (Uro-Vaxom, lyophilised bacterial lysate of 18 E. coli strains) 6 mg orally daily for 3 months; or the sublingual E. coli vaccine MV140 (Uromune), 2 sprays daily for 3 months, where available.
• Antibiotic prophylaxis (after a documented negative culture, consider after discussing options, usually for 6 months, then review):
  • Continuous: nitrofurantoin 50 to 100 mg orally at night (monitor for long term pulmonary, hepatic and neuropathic toxicity; avoid if eGFR under 45); trimethoprim 100 mg orally at night (check folate, avoid in pregnancy first trimester); cefalexin 125 to 250 mg orally at night; fosfomycin 3 g every 10 days (limited data).
  • Post-coital: nitrofurantoin 50 to 100 mg, or cefalexin 250 mg, or trimethoprim 100 mg, taken once within 2 hours after intercourse.
  • Self-start therapy for reliable women with a documented history and prior culture: a 3-day course of nitrofurantoin or pivmecillinam started at the first symptoms, with a urine culture sent before starting, and advised to seek review if symptoms persist beyond 48 hours.
• Treat reversible factors: incomplete emptying (double voiding, intermittent self-catheterisation where indicated), prolapse (pessary or surgery), stones, diabetes control, vaginal atrophy, constipation.
• Review at 3 to 6 months; refer to urology or urogynaecology for relapses, structural abnormalities, haematuria, urinary retention, stones, failed prophylaxis or multi resistant organisms.