Urological complications and their impact on survival after kidney transplantation from deceased cardiac death donors

Renal transplantation in pediatric recipients: Considerations and preoperative assessment strategies

INTRODUCTION AND OBJECTIVE

Renal transplantation in the pediatric population differs from adults in many aspects. This review will focus on the unique issues of the pediatric recipient.

MATERIAL AND METHODS

A narrative review on the scarce literature regarding preoperative evaluation before kidney transplantation of the paediatric recipient with an educational focus was conducted. The literature search allowed for identification of publications in English from January 2000 to October 2022. Published studies were identified by searching the following electronic databases: PubMed (MEDLINE), WHO/UNAIDS, Google-Scholar, Semantic-Scholar and Research Gate. For efficiency and reliability, recent randomized controlled trials, meta-analyses, high quality systematic reviews and large well-designed studies were used if available. Internet searches were conducted for other relevant information (definitions, policies or guidelines).

RESULTS

Management of congenital urogenital anomalies and lower urinary tract dysfunction along with optimal pediatric urological preoperative assessment for renal transplantation in children is addressed in the light of the available literature. Furthermore, particular considerations including pre-emptive transplantation, transplantation of an adult-size kidney into an infant or small child is discussed.

CONCLUSIONS

Outcomes of RT in children have shown progressive improvement over the past 15 years. Transplantation with living related donor gives the best results and pre-emptive transplantation provides with benefits of avoiding dialysis. Surgical and medical considerations in both the pre-transplant and post-transplant management of the pediatric kidney recipient are extremely crucial in order to achieve better short and long-term results.

Paediatric kidney transplantation: Towards a framework for pretransplant urological evaluation

The role of the urologist in paediatric kidney transplantation has evolved alongside advances in management for the various causes of end-stage kidney disease. Improvements in antenatal intervention and postnatal care have seen children with increasingly complex urological anomalies survive until transplant. Once solely responsible for the oversight of a child's surgical care, the paediatric urologist now works within a multidisciplinary transplant team, alongside transplant surgeons, paediatric nephrologists, transplant coordinators, psychologists, social workers, and transitional care specialists. We sought to identify available pretransplant evaluation frameworks to guide urological preparation and decision-making. Drawing from available evidence and reflecting on multi-institutional experience, we propose a streamlined approach to urologic assessment, which recognises that optimal transplant outcomes in this heterogenous cohort require lower urinary tract dysfunction to be carefully defined preoperatively.

Urologic Evaluation and Management of Pediatric Kidney Transplant Patients

Urologic causes of end-stage renal disease are estimated between 25% and 40% of causes. The goal of renal transplantation in chronic kidney disease patients is to provide renal replacement therapy with less morbidity, better quality of life, and improved overall survival compared with dialysis. A patient's urologic history can be a significant source of problems related to infections, recurrence of disease, and surgical complications. Many of the urologic risks are modifiable. Proper evaluation and management can mitigate the potential problems after transplantation, and these patients with complex urologic problems are seen to have similar graft function outcomes.

Perigraft fluid collections after kidney transplantation: Does the type of donor (uncontrolled donation after circulatory death vs. donation after brain death) have a role?

Introduction

Perigraft fluid collection (PFC) is a common complication after kidney transplant. Its etiology is not clear and not all the causes have been identified. The influence of the type of donor has never been evaluated. Our aim was to compare the incidence, severity and management of PFC in recipients of grafts from uncontrolled donors after circulatory death (DCD) with normothermic extracorporeal membrane oxygenation (NECMO) versus recipients of grafts from donors after brain death (DBD).

Material and methods

We conducted a retrospective cohort study of 300 kidney transplants performed in our center between 2007 and 2012. Patients were divided in two groups: 150 recipients of Maastricht II DCD graft and 150 recipients of the DBD graft. Incidence, severity according to Clavien scale and management were analyzed in both groups, and comparison was carried out using Chi-square.

Results

Of the 300 kidney recipients analyzed, 93 (31.4%) suffered PFC, showing no difference between DBD (32.0%) and DCD (30.8%) groups (p = 0.9). Complicated PFC rate (defined as a PFC generating vascular compression, fever or urinary tract obstruction) was 22.9% in the DBD group versus 22.2% in the DCD group (p = 1); most complicated PFC were due to urinary tract obstruction (81%), with no difference between the groups (p = 1). Concerning Clavien scale, 78.5% of the PFC in our series were Clavien I, 19.4% Clavien IIIa and 2.2% Clavien IIIb, with no difference between both groups (p = 1).

Conclusions

PFC is a frequent complication that appears in a third of our patients, showing no difference in the incidence or severity between DBD and uncontrolled DCD graft recipients.

[Management of urological complications after renal transplantation]

Urological complications after kidney transplantation can cause a major reduction in renal function. Surgical complications like urinary leakage and ureteral obstruction need to be solved by a specialist in the field of endourological procedures and open surgical interventions. The article summarizes this and other common urological problems after kidney transplantation.

Independent risk factors for urological complications after deceased donor kidney transplantation

Urological complications after kidney transplantation are mostly related to the ureteroneocystostomy, often requiring interventions with additional costs, morbidity and mortality. Our aim was to assess risk factors for urological complications in deceased donor kidney transplantation. Between January 2000 and December 2011, 566 kidney transplantations were performed with deceased donor kidneys. Recipients were divided in a group with, and a group without urological complications, defined as the need for a percutaneous nephrostomy catheter or surgical revision of the ureteroneocystostomy. Univariate and multivariate analyses were performed. Univariate analysis showed increased number of male donors (p = 0.041), male recipients (p = 0.002), pre-emptively transplanted recipients (p = 0.007), and arterial reconstructions (p = 0.004) in the group with urological complications. Less urological complications occurred in recipients on hemodialysis (p = 0.005). More overall surgical interventions (p<0.001), surgical site infections (p = 0.042), urinary tract infections (p<0.001) and lymphoceles (p<0.001) occurred in the group with urological complications. Multivariate analysis showed that male recipients (p = 0.010) and arterial reconstructions (p = 0.019) were independent risk factors. No difference was found between both groups in patient or graft survival. In conclusion, recipient male gender and arterial reconstruction are independent risk factors for urological complications after deceased donor kidney transplantation. Nevertheless, graft and recipient survival is not different between both groups.

Microvascular damage in type 1 diabetic patients is reversed in the first year after simultaneous pancreas-kidney transplantation

Simultaneous pancreas-kidney transplantation (SPK) is an advanced treatment option for type 1 diabetes mellitus (DM) patients with microvascular disease including nephropathy. Sidestreamdarkfield (SDF) imaging has emerged as a noninvasive tool to visualize the human microcirculation. This study assessed the effect of SPK in diabetic nephropathy (DN) patients on microvascular alterations using SDF and correlated this with markers for endothelial dysfunction. Microvascular morphology was visualized using SDF of the oral mucosa in DN (n = 26) and SPK patients (n = 38), healthy controls (n = 20), DM1 patients (n = 15, DM ≥ 40 mL/min) and DN patients with a kidney transplant (KTx, n = 15). Furthermore, 21 DN patients were studied longitudinally up to 12 months after SPK. Circulating levels of angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2) and soluble thrombomodulin (sTM) were measured using ELISA. Capillary tortuosity in the DN (1.83 ± 0.42) and DM ≥ 40 mL/min (1.55 ± 0.1) group was increased and showed reversal after SPK (1.31 ± 0.3, p < 0.001), but not after KTx (1.64 ± 0.1). sTM levels were increased in DN patients and reduced in SPK and KTx recipients (p < 0.05), while the Ang-2/Ang-1 ratio was normalized after SPK and not after KTx alone (from 0.16 ± 0.04 to 0.08 ± 0.02, p < 0.05). Interestingly, in the longitudinal study, reversal of capillary tortuosity and decrease in Ang-2/Ang-1 ratio and sTM was observed within 12 months after SPK. SPK is effective in reversing the systemic microvascular structural abnormalities in DN patients in the first year after transplantation.