Evaluating Outcomes of Differential Surgical Management of Nonfunctioning Upper Pole Renal Moieties in Duplex Collecting Systems

Objective: To evaluate the management and clinical outcomes of nonfunctioning upper pole moieties treated with either upper pole heminephrectomy or upper pole preservation with lower ureteral reconstruction at a single tertiary institution. Methods: After Institutional Review Board (IRB) approval, patients with duplicated systems undergoing upper pole heminephrectomy, ureteroureterostomy, or common sheath ureteral reimplantation from 2012-2017 were identified. Only patients with a nonfunctioning upper pole moiety on ultrasound or renal scan were included. Patients undergoing upper pole heminephrectomy were compared to those undergoing upper pole preservation with respect to demographics, anatomic variations preoperatively, and postoperative outcomes. Results: Twenty-seven (57%) patients underwent upper pole preservation with lower ureteral reconstruction; 20 (43%) patients underwent upper pole heminephrectomy. Patients undergoing lower ureteral reconstruction were older (1.63 vs 2.76 years, P =.018) and more commonly presented with lower pole vesicoureteral reflux (67% vs 25%, P =.008). No significant difference in postoperative complications was seen between the two groups. After ureteroureterostomy, one patient developed new onset symptomatic reflux to the upper pole requiring intravesical reimplantation. In the heminephrectomy group, 4 of 11 patients with ureteroceles had ureterocelectomy with concomitant lower pole reimplantation. After heminephrectomy, two additional patients required further interventions: ureterocele excision and transurethral polyp excision. Conclusion: For patients with nonfunctional upper poles, lower tract reconstruction is a safe alternative to upper pole heminephrectomy. No significant difference in outcomes was seen. Considering that nearly 1 of 3 of patients with upper pole heminephrectomy required additional lower urinary tract procedures, pursuing upper pole preservation with lower urinary tract reconstruction may be favorable.