Epididymal Cyst

Bladder calculi form because of:

• Urinary stasis
• Bladder outlet obstruction
• Neurogenic bladder
• Foreign body
• Chronic catheterisation
• Reconstructed urinary tract
• Migration of an upper tract stone

In adult men, bladder outlet obstruction is the commonest predisposing factor.

Common compositions include:

• Uric acid
• Calcium oxalate
• Calcium phosphate
• Infection related stones

Removing the stone without addressing the cause produces recurrence.

Symptoms include:

• Frequency
• Dysuria
• Suprapubic pain
• Terminal haematuria
• Interrupted urinary stream
• Acute retention
• Recurrent UTI

Symptoms may worsen with movement as the stone contacts the bladder neck or trigone.

Ultrasound: first line imaging.

If symptoms persist despite negative ultrasound:

• Cystoscopy

or

• CT

provides greater sensitivity.

Investigate the cause using:

• Uroflowmetry
• Post void residual
• Urinalysis and culture
• Renal function
• Stone analysis after removal

Assess prostate and urethral pathology in adult men.

Small migratory stones may pass spontaneously when there is:

• No bladder outlet obstruction
• Normal bladder function
• Small stone burden

Most primary or secondary bladder stones require active removal.

Transurethral cystolithotripsy

Preferred in most adults.

Fragment using:

• Holmium laser
• Thulium laser
• Pneumatic lithotripsy
• Ultrasonic lithotripsy

Remove fragments completely.

Percutaneous cystolithotripsy

Useful when:

• Transurethral access unsuitable
• Urethral stricture
• Very large stone burden
• Reconstructed lower urinary tract

Open cystolithotomy

Useful for selected very large stones or when another open bladder or prostate operation is being performed.

Uric acid stone

Can sometimes be dissolved by oral urinary alkalinisation.

Aim for urine pH consistently above approximately 6.5 using:

• Potassium citrate

or

• Sodium bicarbonate

with frequent pH monitoring.

Treat the cause

If significant BPH caused the stone, consider simultaneous or staged outlet surgery rather than simply removing the calculus.