Can extended upper pole ureterectomy prevent ureteral stump syndrome after proximal approach for duplex kidneys?

INTRODUCTION: Symptomatic duplex kidneys usually present with recurrent urinary tract infection due to ureteral obstruction (megaureter, ureterocele or ectopic ureter) and/or vesicoureteral reflux. Upper-pole nephrectomy is a widely accepted procedure to correct symptomatic duplex systems with poor functioning moieties, also known as upper or proximal approach. The distal ureteral stump syndrome (DUSS) can be a late complication of this approach. There is no consensus upon the length of ureteral dissection and the better approach to symptomatic disease in duplex systems, so we aim to identify if extended ureteral dissection can prevent DUSS in top-down approach. MATERIALS AND METHODS: Forty-four consecutive patients with symptomatic duplex system were retrospectively classified into two groups: those with limited ureteral excision after heminephrectomy (HN) (group-1) and those with extended ureterectomy after HN (group-2). Patients were followed-up for at least 36 months regarding outcomes of distal ureteral stump. RESULTS: Overall complication was 20%. A total of 8 patients required unplanned further surgery in Group-1 (30%) whereas only 1 patient required unplanned surgery in group 2 (6%) (p=0.07). Subgroup analysis showed that Group-1 presented more DUSS requiring surgery during follow-up than group-2 (p=0.04). Factors possibly affecting complications incidence (such as ureterocele or ectopic ureter) did not differ between groups (p=0.72 and p=0.78). CONCLUSION: Upper pole nephrectomy should be performed with extended distal ureteral dissection to prevent ureteral stump complications.