Endoscopic dilatation/incision of primary obstructive megaureter. A systematic review. On behalf of the EAU paediatric urology guidelines panel.

INTRODUCTION: Historically, ureteral reimplantation (UR) has been the gold standard for treatment of primary obstructive megaureter (POM) with declining renal function, worsening obstruction, or recurrent urinary tract infections. In infants, open surgery with reimplantation of a grossly dilated ureter into a small bladder, can be technically challenging with significant morbidity. Therefore, less invasive endoscopic management such as dilatation or incision of the ureter-vesical junction, has emerged as an alternative to reimplantation during the last decades.

OBJECTIVE: To systematically evaluate the effectivity, safety, and potential benefits of endoscopic treatment (dilatation with or without balloon or incision) of POM in comparison to UR.

STUDY DESIGN: A systematic review was conducted. Randomized controlled trials (RCTs), nonrandomized comparative studies (NRSs), and single-arm case series including a minimum of 20 participants and a mean follow-up more than 12 months were eligible for inclusion.

RESULTS: Of 504 articles identified, 8 articles including 338 patients were eligible for inclusion (0 RCTs, 1 NRSs, and 7 case series). Age at time of surgery was minimum 15 days to a maximum of 192 months. Indications for endoscopic treatment (ET) included patients with loss of split renal function (>10%) and worsening of hydroureteronephrosis. The studies analysed reported a success rate ranging from 35% to 97%. Success was defined as stabilization of differential renal function without further procedures. A post-operative complication rate of 23-60% was reported (mostly transient haematuria, urinary tract infections and stent migration or intolerance). In 14% of the cases salvage UR following initial ET, was performed due to relapse of symptomatic POM.

CONCLUSION: Endoscopic treatment for persistent or progressive POM in children is a minimally invasive alternative to UR with a long-term modest success rate. Additionally, it can be performed within a wide age span, with equal success rate and complication rates.