Dismembered Pyeloplasty in Infants 6 Months Old or Younger With and Without External Trans-anastomotic Nephrostent: A Prospective Randomized Study.

Objective: To compare the outcome of dismembered pyeloplasty in infants with and without external nephro-ureteric stent (ENUS) for treatment of congenital ureteropelvic junction obstruction.

Methods: This is a parallel, randomized comparative study between October 2013 and September 2014. Thirty infants ≤6 months old with ureteropelvic junction obstruction indicated for dismembered pyeloplasty were randomly assigned (block randomization, closed envelope method) into two groups: group A (stentless) and group B (ENUS). Infants with solitary kidney, gross pyuria, huge pelvis, vesicoureteric reflux, or other renal anomalies were excluded. Operative data, complications, and ultrasonographic and nuclear scintigraphy criteria were compared after at least 18 months of follow-up using Student t, Mann-Whitney U, Kruskal-Wallis, chi-square, and Fisher exact tests when appropriate. Occurrence of urinary leakage was the primary outcome.

Results: Included patients completed the study with intention-to-treat analysis. All children had normal renal function. The mean operative time was 85.3 ± 6.3 (60-90) minutes in group A and 92.6 ± 15.3 (70-120) minutes in group B (P = .2). Although there was a significant postoperative improvement in each group in split renal function and anterior-posterior renal pelvis diameter, there was no significant difference between both groups. The mean hospital stay for group A and group B was 5.9 ± 2 (4-10) days versus 3.5 ± 0.8 (2-5) days, respectively (P < .001). Postoperative urinary leakage was reported only in group A (40%). All complications were managed by double J insertion. Auxiliary interventions were higher in group A. The overall success rate was 93.4%. Redo pyeloplasty was performed in one case in each group.

Conclusion: ENUS significantly reduces hospital stay and complications. It saves the infant hazards of auxiliary interventions under general anesthesia for management of leakage or double J removal if placed at time of pyeloplasty.