Laparoscopic pyeloureterostomy for ureteropelvic junction obstruction occurring in incomplete ureteral duplication of the solitary kidney

INTRODUCTION: Ureteropelvic junction obstruction associated with ureteral duplication is rare, with prevalence reported to be around 2–7%. Ureteropelvic junction obstruction of the lower pole with both complete and incomplete duplex systems is a common cause of obstruction. Here, we report a case of ureteropelvic junction obstruction associated with incomplete ureteral duplication of the solitary kidney successfully treated by pyeloureterostomy. CASE PRESENTATION: The patient was a 39‐year‐old woman who presented with right hydronephrosis, right back pain, and deteriorated renal function. The patient was referred to our department from the rheumatology department. Her medical history included congenital left renal hypoplasia, Sjogren's syndrome, and hyperphospholipid antibody syndrome. CONCLUSION: We encountered a case of hydronephrosis occurring in a solitary kidney with incomplete ureteral duplication. This case was successfully managed after pyeloureterostomy.