The utility of native ureter in the management of ureteral complications in children after renal transplantation

Evaluation and Management of Urological Complications Following Pediatric Kidney Transplantation: Experience from a Single Tertiary Center

Background/Objectives: Kidney transplantation is the treatment of choice for children with end-stage renal disease (ESRD), but its outcome can be affected by urological complications, with incidence rates of 2.5-25%. The aim of this study was to evaluate the occurrence of urological complications and their management in a cohort of pediatric kidney transplant recipients. Materials and Methods: A retrospective analysis on 178 patients who received a renal transplant at our Pediatric Kidney Transplant Center between 2011 and 2023 was conducted. Demographic and clinical data were analyzed. Urological complications were categorized as early, intermediate, or late based on their onset time. Results: Out of 178 patients, 28 (15.7%) experienced urological complications. Most patients (61%) had a pre-existing uropathy. Early complications (7-30 days) were all obstructive, namely, ureterovesical junction obstruction and perirenal collections. Intermediate complications (1-3 months) comprised ureteral stenosis, symptomatic vesicoureteral reflux (VUR), and obstructive lymphocele. Late complications (>3 months) included symptomatic VUR and ureteral stenosis, with one case leading to ureteral rupture. Early complications were often detected due to acute graft dysfunction, while late ones were mainly identified during routine clinical, laboratory, or ultrasound follow-up. Urological complications requiring surgical or endoscopic therapy were 13.4%. Most ureteral stenoses were treated with initial endoscopic stents, followed by definitive surgery. VUR was treated with endoscopic correction with a high success rate (75%), while open surgery was reserved for cases where initial treatments failed or complications recurred. No clear correlations were found between patient characteristics and risk of urological complication. Urological complications required multiple diagnostic procedures and therapeutic interventions (+2.5 admissions in mean and approximately +EUR 24,000) compared to an uncomplicated post-transplant course. However, they did not significantly impact transplant outcomes, with a graft survival rate comparable to that of the control group. Conclusions: Regular post-transplant follow-up is crucial, especially for patients with known risk factors, to allow for timely detection and treatment of urological complications, avoiding detrimental effects on graft function and improving transplantation outcomes.

An experimental study of magnetic compression technique for ureterovesical anastomosis in rabbits

This study aimed to explore the feasibility of the magnetic compression technique (MCT) for ureterovesical anastomosis in a rabbit model with ureteral obstruction. The distal ureteral obstruction model using female New Zealand rabbits was induced by ligating the distal end of the right ureter with silk thread for four weeks. A pair of cylindrical NdFeB magnets (daughter magnet and parent magnet) with a hole in the center was used for the ureterovesical anastomosis. The daughter magnet and the parent magnet were respectively placed close to the obstruction site through the dilated proximal ureter and urethra, and then the daughter-parent magnets pair was attracted together automatically. Postoperative X-rays were taken to confirm the position of the magnets. The anastomotic stoma specimens were obtained two weeks postoperatively, and the anastomotic stoma formation was observed by the naked eye and histological staining. The operation time and the anastomotic burst pressure were measured. The ureter was significantly dilated in the fourth week after ligation, which satisfied the placement of the daughter magnet. The ureterovesical magnet placements were successfully performed in ten experimental rabbits, with an operation time of 36.5 ± 6.09 min. The parent and daughter magnets attracted each other well and were subsequently removed through the urethra two weeks postoperatively, resulting in the establishment of ureterovesical anastomosis. The anastomotic burst pressure was 147.5 ± 14.59 mmHg. Gross specimens and histological examination of the anastomotic stoma showed that the anastomotic stoma healed well. MCT is feasible and simple for ureterovesical anastomosis.

Ultrashort anisoperistaltic end-to-side ureteroureterostomy in renal transplantation

The improvement of surgical techniques in kidney transplantation aims to reduce the incidence of post-transplant complications, contributing to the reduction of hospital stay, related costs, morbidity and mortality, in addition to improving the quality of life of patients. The choice of the best technique is influenced by several factors and the most common technique for urinary tract reconstruction in transplants is performed with implantation of the ureter of the graft in the caudal position, with the anastomosis performed in the bladder. However, the kidney pole can be inverted and the graft ureter anastomosis can be performed directly on the recipient's ureter, facilitating venous and ureteral anastomoses and reducing urological complications.

Overview of pediatric kidney transplantation

Kidney transplantation is the treatment of choice for pediatric patients with end-stage kidney disease. Unlike adult recipients undergoing transplantation, special considerations must be taken when transplanting children based on the underlying etiology of kidney disease, previous surgical procedures, anatomical limitations and necessary technical adjustments. Additionally, the choice of donor must be measured to ensure optimal graft survival given a longer post-transplant life expectancy. Those topics as well as frequently encountered postoperative complications are also discussed in this publication.

Anastomose uretero-ureteral término-lateral anisoperistáltica ultracurta no transplante renal

RESUMO O aprimoramento das técnicas cirúrgicas no transplante renal tem o objetivo de reduzir a incidência de complicações pós-transplante, contribuindo com a redução do tempo de internamento hospitalar, os custos relacionados, a morbidade e a mortalidade, além de melhorar a qualidade de vida dos pacientes. A escolha da melhor técnica é influenciada por diversos fatores e a técnica mais comum de reconstrução do trato urinário nos transplantes é a realizada com implante do ureter do enxerto na posição caudal, com a anastomose feita na bexiga. No entanto, pode-se inverter o polo do rim, posicionando o polo inferior cranialmente e realizar a anastomose do ureter do enxerto diretamente no ureter do receptor, facilitando a anastomose ureteral e diminuindo as complicações urológicas.