Urethral Diverticulum in Men

Urethral diverticulum in men is a saccular outpouching of the urethral wall that communicates with the lumen and fills during voiding. It is rare.

Most are anterior, arising from the penile or penoscrotal urethra, and may be congenital (a deficient ventral spongiosum or a distal valve like lip that causes obstruction) or acquired (distal stricture, hypospadias repair, trauma, infection, instrumentation). Posterior diverticula are rarer and are usually related to a prostatic utricle or to ductal cysts.

Pathophysiology. Distal obstruction raises pressure behind it and dilates a weak ventral wall segment.

Stagnant urine promotes infection and stone formation, and chronic inflammation raises, rarely, the risk of carcinoma in the sac.

A soft ventral penile swelling that enlarges on voiding and empties on pressure, post-void dribble, weak stream, recurrent urinary infection, dysuria, haematuria, and a palpable stone. Small diverticula may be asymptomatic. Complications are stones, infection and obstruction.

• Retrograde urethrography with voiding cystourethrography shows the sac, its neck and any distal obstruction.
• High frequency ultrasound defines the sac wall, any stones and the spongiosum.
• Urethroscopy to inspect the neck, valve lip or stricture.
• MRI for posterior or complex sacs.
• Urinalysis and culture, uroflowmetry, creatinine and renal ultrasound.

Differential diagnosis.

• Cowper duct cyst or syringocele
• Urethral duplication
• Distal valve or lip
• Paraurethral cyst
• Hypospadias repair complication
• Urethral stricture
• Periurethral abscess
• Prostatic utricle cyst (posterior)

• Asymptomatic small diverticula without obstruction: observation.
• Treat infection first, with antibiotics adjusted to culture, and remove or fragment stones.
• Treat distal obstruction (valve incision, stricture repair) as the first step, and the sac may shrink.
• Symptomatic or large sacs: excision of the diverticulum with layered closure of the urethra over a catheter. Alternatives for wide mouth sacs are marsupialisation or urethral flap reconstruction, and the repair must avoid creating a stricture.
• Catheter for 7 to 14 days, longer after a complex repair, with a urethrogram before removal if the repair was extensive.
• Send excised tissue for histology.

Monitoring. Uroflowmetry and symptom review at 3 and 12 months, with urethrography for recurrent symptoms.

Referral and escalation. Refer to urology, with reconstructive input for large or recurrent sacs. Urgent referral for retention, infection or suspicion of malignancy.