Ipsilateral ureteroureterostomy for ureteral duplication anomalies: predictors of adverse outcomes

Ipsilateral ureteroureterostomy (UU) has gained popularity for treating ureteral duplication (UD) associated with obstruction or vesicoureteral reflux (VUR). Several studies have demonstrated its high success rate and low morbidity. This study aimed to identify the predictors of adverse outcomes associated with UU.

A retrospective chart review was conducted for patients with UD treated with UU at the study institution. Patients with less than 6 months of follow-up were excluded. Charts were reviewed for demographics, pre-operative imaging, surgical indications, operative notes, and follow-up data. Pre-operative and intra-operative variables were tested for association with adverse outcomes including unplanned surgery, worsening hydronephrosis, and febrile UTI recurrence.

A total of 35 patients underwent UU for UD between 2009 and 2017 at the study institution. The majority (33/35) had a distal anastomosis. A concomitant re-implantation of the recipient ureter was performed in 9 (25.7%) patients. After a median follow-up of 36.7 months, adverse outcomes developed in 9 patients (25.7%). No further surgery was required in 88.6% of the subjects. Adverse outcomes were associated with female gender (p = 0.048) and hydronephrosis of both upper and lower moieties (p = 0.015) and were more likely associated with ectopic ureteroceles (50%, p = 0.074) and having a concomitant re-implant performed (44.4%, p = 0.19) (table).

In this study, the low re-operation rates of UU for treating UD in patients with ectopic ureters or intravesical ureteroceles was demonstrated. The majority of patients with ectopic ureteroceles treated with UU and concomitant ureteral re-implantation had worsening hydronephrosis of both moieties and recurrent febrile UTI in the absence of mechanical obstruction. Interestingly, some of them had progression of hydronephrosis after excision of the upper pole. While worsening of hydronephrosis of the recipient moiety after UU was historically attributed to yo-yo reflux, most of the study patients did not have worsening hydronephrosis despite having distal anastomosis. Therefore, mechanical obstruction should be ruled out, and any underlying bladder dysfunction should be aggressively managed in patients with worsening hydronephrosis or recurrent UTI after UU before considering additional surgery.

Ureteroureterostomy is a successful option for UD with a low risk of adverse events in patients with ectopic ureters or intravesical ureteroceles. However, it should be cautiously considered in patients with hydronephrosis of both moieties, with ectopic ureteroceles, or if a concomitant re-implant is needed.