Renal transplantation and congenital anomaly of the kidney and urinary tract

Abstract

Paediatric renal transplantation in children differs from adult series because of the high incidence of abnormalities of the lower urinary tract. We report our experience concerning five children with end-stage renal disease and associated bladder dysfunction due to posterior urethral valves, and lower urinary tract abnormalities (‘valve bladder’), who underwent renal transplantation without prior correction of the uropathy. Of 151 paediatric patients (aged 34 months to 23 years) who underwent renal transplantation, 58 had lower urinary tract abnormalities, and 42 underwent surgical correction of the uropathy prior to renal transplantation. In 15 patients, the uropathy was fibrotic bladder secondary to posterior urethral valves (‘valve bladder’). After clinical and urodynamic evaluation, all 15 patients were considered as candidates for bladder augmentation. In 10 patients, the bladder augmentation was performed prior to renal transplantation. The remaining five patients presented with oligoanuria at the time of the evaluation, and the decision to consider bladder augmentation was postponed until the post-transplant period. At the time of renal transplantation, 2 of the 5 patients underwent ureterostomy, and three had a ureteral reimplant associated with a suprapubic catheter for 2 months. Periodic assessment of renal function and bladder capacity/compliance was performed, as was renal ultrasound. After 4 months, the five patients were re-evaluated for the need for bladder augmentation. At 1, 2, 3 and 4 months follow-up, the five patients had normal renal function with improvement of bladder capacity and absence of hydronephrosis. In 3 of the 5 children, bladder augmentation was judged to be no longer necessary due to the complete restoration of clinical and urodynamic parameters. Therefore, renal transplantation can be safely performed without pre-emptive reconstruction of the lower urinary tract. When possible, ureteral reimplantation is recommended, even in a very small valve bladder, since the initial indication for bladder augmentation may be modified once normal diuresis has been restored.