Risk Factors and Treatment Success for Ureteral Obstruction After Pediatric Renal Transplantation

TLDR

Ureteral obstruction after pediatric renal transplantation is a poorly understood, challenging complication that requires clinical vigilance. The study aims to identify risk factors and evaluate treatment efficacy for ureteral obstruction in pediatric renal transplant recipients. The authors performed a retrospective review of 449 children (526 transplants) from 1984–2008, collecting donor/recipient demographics, surgical details, and outcomes. Ureteral obstruction occurred in 8% of cases; posterior urethral valves were the sole significant risk factor (OR 4.93 univariate, 7.59 multivariate), with 48% presenting within 100 days, yet obstruction did not increase graft loss or mortality.

Abstract

Risk factors and treatment efficacy for ureteral obstruction following pediatric renal transplantation are poorly understood. We describe a single center experience with pediatric transplant recipients in an effort to discern risk factors and treatment efficacy.We retrospectively reviewed the pediatric renal transplant database at our institution from January 1984 to March 2008. Donor and recipient demographics, treatment indications, graft characteristics, surgical techniques, treatment course, complications and graft outcomes were abstracted from clinical records.A total of 449 children (mean age 8.6 years) who underwent 526 renal transplants were included in the study. Ureteral obstruction requiring intervention developed in 42 cases (8%). Recipient age and gender, recipient and donor race, donor harvest technique, ureterovesical anastomosis with or without stenting, number of donor arteries, number of human leukocyte antigen mismatches, prior renal transplant and ischemia time were not significantly associated with increased incidence of ureteral obstruction. Renal failure secondary to posterior urethral valves was the only parameter significantly associated with increased incidence of ureteral obstruction (univariate OR 4.93, p = <0.0001; multivariate point estimate 7.59, p <0.0001). Of patients with ureteral obstruction 48% presented within 100 days after transplant. Kaplan-Meier analysis showed significantly decreased ureteral obstruction-free survival in patients with vs without posterior urethral valves (log rank test, p <0.0001). Ureteral obstruction, stenting and dilation were not significantly associated with increased graft loss or patient death.Ureteral obstruction after renal transplantation in children is a challenging complication that demands clinical vigilance. Posterior urethral valves appear to be a significant risk factor for post-transplant ureteral obstruction likely due to local factors such as ischemia, thick bladder wall and collagen remodeling.