Female Urethral Diverticulum

Female urethral diverticulum is an outpouching of the urethral mucosa into the periurethral tissue (anterior vaginal wall) that communicates with the urethral lumen through a narrow ostium.

• It is found in 1 to 6 percent of women (often asymptomatic), usually aged 30 to 60 years.
• Cause: infection and obstruction of periurethral glands (Skene), obstetric trauma, urethral instrumentation or surgery, urethral dilation, and congenital.
• Most are in the middle third of the urethra and open at the posterolateral aspect; saddle (circumferential) forms exist.

Classic triad: dysuria, dyspareunia and post-micturition dribbling; the "three Ds"; present in only a minority.

• Recurrent urinary tract infections, urethral or vaginal pain, voiding symptoms, urgency, frequency, urinary incontinence, haematuria, vaginal discharge.
• Examination: tender anterior vaginal wall mass, pus or urine expressed from the meatus on massage of the mass.
• Differential diagnosis: Skene gland cyst, Gartner duct cyst, vaginal wall cyst, cystocele, ectopic ureterocele, urethral prolapse, periurethral abscess, urethral carcinoma, endometriosis, vaginal tumour, interstitial cystitis.
• Complications: stones in the diverticulum (up to 10 percent), recurrent infection, abscess, carcinoma (about 5 percent; adenocarcinoma most common), fistula, urinary incontinence, painful intercourse.

Pelvic examination; urinalysis and culture.

• Magnetic resonance imaging of the pelvis (T2 weighted, with endovaginal coil if available) is the best test: well defined fluid-filled sac with narrow neck, delineates size, shape and wall; identifies stones or tumour.
• Voiding cystourethrography (shows diverticulum filling on voiding), transvaginal ultrasound, urethroscopy to identify the ostium, double balloon urethrography.
• Cytology or biopsy of any solid component.

Supportive: observation of asymptomatic diverticula; warm sitz baths; analgesia (paracetamol 1 g every 6 hours); avoid intercourse in the acute phase.

Pharmacological

• Acute infection: ciprofloxacin 500 mg twice daily for 7 to 14 days (good tissue penetration), or amoxicillin-clavulanate 625 mg three times daily for 7 to 14 days, or cefixime 400 mg daily; adjust to culture.
• Suppressive prophylaxis if recurrent infection awaits surgery: nitrofurantoin 100 mg at night or cefalexin 250 mg at night.
• Antimuscarinic therapy for urgency (solifenacin 5 mg daily).

Procedures

• Surgical excision (diverticulectomy) through the anterior vaginal wall with multilayer closure (urethral mucosa, periurethral fascia, vaginal wall in non-overlapping suture lines) and a Martius fat pad interposition in complex cases; urethral catheter for 7 to 14 days, with voiding cystourethrogram before removal; success 90 to 95 percent.
• Transvaginal marsupialisation (diverticulotomy) for distal diverticula near the meatus.
• Transurethral incision of the ostium or endoscopic unroofing for selected small diverticula (higher recurrence).
• Pre-operative planning with magnetic resonance imaging; operate once acute infection has settled.

Special groups: pregnancy (conservative management, antibiotics for infection, surgery after delivery), elderly (conservative if asymptomatic), diverticular carcinoma (radical surgery with oncology care).

Red flags: solid component or enhancement, haematuria, rapid growth, retention, recurrent abscess.

Follow-up: review at 6 weeks and 3 months; voiding symptoms, stress incontinence (10 to 20 percent after surgery), recurrence (up to 10 percent), urethrovaginal fistula and stricture; long term surveillance in carcinoma.