A patient with an ectopic, pelvic kidney with congenital ureteropelvic
junction obstruction was treated by retrograde, ureteroscopic endopye
lotomy without percutaneous access. Preoperative ureteral stent placem
ent and angiography facilitated the procedure. The patient had an unev
entful recovery with improved drainage from the involved collecting sy
stem demonstrated by renal scintigraphy 6 months postoperatively. Uret
eroscopic endopyelotomy avoids the need for percutaneous access, which
may be difficult in patients with ectopic, malrotated kidneys and app
ears particularly well suited to the treatment of ureteropelvic juncti
on obstruction in such cases.