Long-term outcome of JJ stent insertion for primary obstructive megaureter in children

Background/aim Endoscopic stenting is an accepted treatment option for children with symptomatic or progressive primary obstructive megaureter (PROM). Here, long-term outcomes with endoscopic stenting are reviewed. Methods Patients with PROM treated surgically over a 12-year period were identified using a prospectively maintained departmental database. Data were analysed using Microsoft Excel 2013 and unpaired t-tests through GraphPad Software QuickCalcs. Results Fifty-seven patients with PROM were surgically managed in the study centre from 2005 to 2017. Twenty-nine of fifty-seven patients had the stent as the primary procedure, whereas the remainder had ureterostomy, re-implantation or nephrectomy. Six patients had bilateral PROM, giving a total of 35 renal units that were fully analysed. There was 7:1 male predominance, and 20 of 29 patients (69%) were diagnosed antenatally. The median age at stent insertion was 8 months (40 days-10 years); the median prestent ureteric diameter was 19 mm and the median pre-operative function on MAG3 was 44%. Cystoscopic stent insertion was feasible in all patients. The stent was left for a median of 183 days. In 9 of 35 (26%) renal units, the JJ stent was a successful sole long-term treatment, with median follow-up of 5 years and 8 months. The success rate was not different in children aged < 1 year (8/22; 36%) in comparison to children aged > 1 year (1/13; 8%), P = 0.1. The remaining 26 renal units required further surgical intervention: ureteric re-implantation in 25 and nephrectomy in one. Indications for further surgery were stent complications in 11 renal units and stent failure in 15 (Table 1). Complications related to the stent were noted in 14 renal units (41%), half being stent migration. Other complications included UTIs, stent encrustation and recurrent haematuria. There was no identifiable prestent parameter, whether clinical or radiological, that could predict which patients were likely to be successfully managed solely by stent insertion. Stent insertion was never successful as a definitive procedure when the distal ureteric diameter was > 12 mm on the ultrasound after stent removal. Discussion Success rates with primary stenting as a sole treatment for PROM was 26%, which is less than that seen in other reports (50-66%). This may be attributed to the long-term follow-up in this study, together with the strict criteria for success. Conclusion In the authors' experience, cystoscopically inserted JJ stents are of limited success as the sole treatment for PROM. In infants aged < 1 year, stent insertion remains a reasonable temporising measure until the infant is old enough for a definitive procedure. [GRAPHICS]