Editing CUA: Ureteral Calculi (2015) (section)

=== Urinary diversion ===

* '''High risk of stone formation due to (6):'''
*# '''Metabolic abnormalities'''
*# '''Recurrent infections with urease-splitting organisms'''
*# '''Prolonged urinary stasis'''
*# '''Prolonged exposure of urine to non-absorbable materials'''
*# '''Anatomical changes following diversion'''
*# '''Reflux of mucous into the upper tract'''
* '''Most common stone types are magnesium ammonium phosphate (struvite) and calcium phosphate'''
* '''Treatment'''
** '''Small, non-obstructive, asymptomatic stones could be managed conservatively'''
** '''SWL can be attempted for obstructive stones'''
** '''If SWL fails, retrograde URS with laser lithotripsy could be attempted'''
** '''If percutaneous approach contemplated, need CT scan to determine if there are overlying bowel loops. If present, ultrasound guided access needed'''
** When percutaneous procedures fail, '''ureterolithotomy is the last option'''
* '''Close follow-up mandatory because of risk of re-growth and recurrence''' (63% at 5-year follow-up)