Survival advantage of pediatric recipients of a first kidney transplant among children awaiting kidney transplantation

Holistic care and symptom management for pediatric kidney transplant recipients

While many aspects of life may improve substantially for children and young people undergoing kidney transplant, there may be new challenges including symptoms that can be detrimental to health-related quality of life. Addressing symptoms requires attention to patient and family perspectives and a holistic approach grounded in symptom management. The interdisciplinary pediatric nephrology transplant team should be attuned to the prevalence of common symptoms including fatigue, anxiety, depression, post-traumatic stress, pain, and sleep disturbances, as well as poor body image and sexual health. These common symptoms require regular assessment with a focus on appropriate interventions and how care may be impacted by transplant status.

Kidney transplant to vesicostomy: A safe strategy for children with end stage renal disease and lower urinary tract anomalies

INTRODUCTION

Resolution of underlying urinary tract anomalies prior to kidney transplantation in patients with end stage renal disease (ESRD) secondary to uropathy, has been historically supported under the argument that this would help prevent infectious complications and graft loss. We propose to perform earlier kidney transplantation with a transient vesicostomy, deferring resolution of the uropathy to the post-transplantation period. The aim of this study was to evaluate the outcomes of kidney transplantation in children with a vesicostomy.

MATERIAL AND METHODS

A retrospective, multicenter study was performed including all patients under 18 years of age who underwent kidney transplantation with a vesicostomy, between January 2005 and December 2020 and had at least one year of follow up. Data related with the indication and timing of vesicostomy, time until transplantation, post-transplantation complications, urinary tract infections (UTI) and graft survival rate were collected.

RESULTS

Of the 758 transplantations performed in the study period, 16 patients met the inclusion criteria. Mean age at transplantation was 58 months (range 20-151), and mean weight was 13.5 Kg (range 8.4-20). Mean time from vesicostomy to kidney transplantation was 30 months (range 0-70). There were 2 (12.5%) ureteral complications that required reoperation. Eighteen episodes of UTI were identified in 8 patients (50%), accounting for 0.4 UTIs per patient-year of follow-up. UTIs did not lead to graft loss in any of the cases. Urinary tract reconstruction was performed in 5 patients (31.3%) at an interval of 1-91 months post-transplantation. After a mean follow-up of 44.8 months (range 13-200) from transplantation, patients with vesicostomy had a mean creatinine clearance of 86.6 ml/min/1.73 m2, with a mean serum creatinine level of 0.6 mg/dl. Graft survival rate was 100%.

DISCUSSION

Early kidney transplantation into a vesicostomy permits a resolution of the ESRD, avoiding deleterious effects related to dialysis. With a low rate of UTIs, we found no graft loss due to infectious complications. This strategy permits careful planning and better timing for the urinary tract reconstruction without delaying kidney transplantation.

CONCLUSION

Kidney transplantation in pediatric patients with vesicostomy seems to be a safe and effective strategy. UTI rate was similar to that reported in the literature of patients with corrected urinary anomalies undergoing kidney transplantation without urinary diversion.

Pediatric Kidney Transplantation: Cancer and Cancer Risk

Children with end-stage kidney disease (ESKD) face a lifetime of complex medical care, alternating between maintenance chronic dialysis and kidney transplantation. Kidney transplantation has emerged as the optimal treatment of ESKD for children and provides important quality of life and survival advantages. Although transplantation is the preferred therapy, lifetime exposure to immunosuppression among children with ESKD is associated with increased morbidity, including an increased risk of cancer. Following pediatric kidney transplantation, cancer events occurring during childhood or young adulthood can be divided into two broad categories: post-transplant lymphoproliferative disorders and non-lymphoproliferative solid tumors. This review provides an overview of cancer incidence, types, outcomes, and preventive strategies in this population.

Trajectories of eGFR after kidney transplantation according to trajectories of eGFR prior to kidney replacement therapies in children with chronic kidney disease

BACKGROUND

In children with chronic kidney disease (CKD), certain risk factors are associated with faster eGFR decline and earlier kidney failure. Whether these factors have lingering effects on post-transplant eGFR trajectory remains unclear. We characterized pre- and post-transplant eGFR trajectories in pediatric kidney transplant recipients by their pre-kidney replacement therapy (KRT) risk factors.

METHODS

We studied eGFR trajectories before KRT initiation and after transplantation among Chronic Kidney Disease in Children (CKiD) Study participants. We used mixed-effects models to compare pre-KRT versus post-transplant eGFR trajectories within individual participants by 7 pre-KRT risk factors: glomerular/non-glomerular etiology, race, preemptive transplant, proteinuria, albuminuria, and systolic/diastolic blood pressure (SBP/DBP).

RESULTS

We analyzed 1602 pre-KRT and 592 post-transplant eGFR measurements from 246 transplant recipients. Mean annual eGFR decline was decreased from 18.0% pre-KRT (95%CI, 16.1-19.8) to 5.0% post-transplant (95%CI, 3.3-6.7). All 7 pre-KRT risk factors showed strong associations with faster pre-KRT eGFR decline, but not with post-transplant eGFR decline; only albuminuria, high SBP, and high DBP reached statistical significance with notably attenuated associations. In our multivariable model of the pre-KRT risk factors, post-transplant eGFR decline was more rapid only when albuminuria and high SBP were both present.

CONCLUSIONS

eGFR decline substantially slows down after transplant even among children with rapidly progressing forms of CKD. Nonetheless, those who had albuminuria and high SBP before KRT might continue to show faster eGFR decline after transplant, specifically when both risk factors were present. This subgroup might benefit from intensive pre-transplant management for at least one of the two risk factors. A higher resolution version of the Graphical abstract is available as Supplementary information.

Survival of Tunneled Double Lumen-Cuffed Catheters in Children on Maintenance Hemodialysis - A Retrospective Cohort Study

Introduction

Survival of tunneled cuffed catheters (TCC), used widely in children, is complicated by infections and catheter dysfunction. In resource limited settings, where risk of complications could be higher and waiting period for transplantation longer, catheter survival determines patient survival. This study was conducted to determine infection free catheter survival rates, incidence of catheter failure and associated risk factors.

Methods

Children <18 years of age receiving maintenance hemodialysis through TCC at nephrology division of a pediatric hospital, over a period of 6 years. Data was collected with consecutive selection by a complete enumeration technique from pre-collected data sheets in the records. Exposure detected were catheter infections, thrombosis, and mechanical complications.

Results

Forty-five TCCs in 36 children studied for 12,590 catheter days showed catheter failure in 36%, due to catheter related infections in 75% and mechanical complications in 25%. The incidence of complications per 1000 catheter days was 1.19 infection, 1.03 thrombus, and 0.39 mechanical. Catheter-related blood stream infection (CRBSI) (15/36) was associated with thrombus in nine and led to mortality in three. The mean infection free catheter survival was 449 ± 42 days for cohort with 388 ± 38 days in Group A (premature catheter removal) and 593 ± 43 days in Group B (elective removal) (P = 0.03). Catheterization duration of 267 days predicted CRBSI (sensitivity 93%, specificity 66.7%) with area under the curve of 0.808.

Conclusions

Median infection free catheter survival was 449 days with catheter failure in 36%. CRBSI was the main cause of failure. Duration of catheterization greater than 267 days was a predictor of CRBSI.

Why Do Not All Living Kidney Donor Candidates Are Accepted for Donation? A Pediatric Center Experience

BACKGROUND

Living donor kidney transplantation is the best type of renal replacement therapy for patients with end-stage renal disease. Living kidney donors (LKDs) undergo an extensive evaluation before donating, and many potential LKDs are declined. This study aimed to define the reasons for the decline in LKD candidates referred to our center.

METHODS

We retrospectively analyzed clinical data of all potential LKDs evaluated between January 2001 and December 2021 at our institution,Western National Medical Center, Pediatric Hospital. Data were obtained by review of an electronic database.

RESULTS

A total of 1332 potential LKDs were evaluated, 796 (59.7%) successfully donated; 20 (1.5%) had a complete evaluation, were accepted for donation, and were on the waiting list for intervention; 56 (4.2%) continued in the evaluation process; 200 (15%) were discharged from the program due to administrative aspects, death (donor or receptor), or cadaveric renal transplantation in order of frequency; 56 (4.2%) withdraw by personal choice; and 204 (15.3%) were rejected for donation. Donor-related reasons included medical contraindications (n = 134, 65.7%), anatomic contraindications (n = 38, 18.6%), immunologic barriers (n = 18, 8.8%), and psychological reasons (n = 11, 5.4%).

CONCLUSIONS

Despite the large number of potential LKDs, a significant proportion did not proceed for donation for different reasons; in our description, it represents 40.3%. The largest proportion is because of donor-related causes, and most of the reasons result from the candidate's unnoticed chronic diseases.

Kidney transplant access for children and young adults with congenital anomalies of the kidney and urinary tract

PURPOSE

Although congenital anomalies of the kidney and urinary tract (CAKUT) are among the leading causes of end-stage kidney disease (ESKD) in children and young adults, kidney transplantation access for this population has not been well studied in the US. We compared transplantation access in the US based on whether the etiology of kidney disease was secondary to CAKUT, and additionally by CAKUT subgroups (anatomic vs. inherited causes of CAKUT).

METHODS

Using the United States Renal Data System, we conducted a retrospective cohort study of 80,531 children and young adults who started dialysis between 1995 and 2015. We used adjusted Cox models to examine the association between etiology of kidney disease (CAKUT vs. non-CAKUT, anatomic vs. inherited) and receipt of kidney transplantation, and secondarily, receipt of a living vs. deceased donor kidney transplant.

RESULTS

Overall, we found an increased likelihood of kidney transplantation access for participants with CAKUT compared to those without CAKUT (HR 1.23; 95% CI 1.20-1.27). Among the subset of individuals with CAKUT as the attributed cause of ESKD, we found a lower likelihood of kidney transplantation in those with anatomic causes of CAKUT compared to those with inherited causes of CAKUT (adjusted HR 0.85; 0.81-0.90).

CONCLUSION

There are notable disparities in kidney transplantation rates among CAKUT subgroups. Those with anatomic causes of CAKUT started on dialysis have significantly reduced access to kidney transplantations compared to individuals with inherited causes of CAKUT who were initiated on dialysis. Further studies are needed to understand barriers to transplantation access in this population.

Multidrug resistant 1 (MDR1) C3435T and G2677T gene polymorphism: impact on the risk of acute rejection in pediatric kidney transplant recipients

BACKGROUND

Tacrolimus is the backbone drug in kidney transplantation. Single nucleotide polymorphism of Multidrug resistant 1 gene can affect tacrolimus metabolism consequently it can affect tacrolimus trough level and incidence of acute rejection. The aim of this study is to investigate the impact of Multidrug resistant 1 gene, C3435T and G2677T Single nucleotide polymorphisms on tacrolimus pharmacokinetics and on the risk of acute rejection in pediatric kidney transplant recipients.

METHODS

Typing of Multidrug resistant 1 gene, C3435T and G2677T gene polymorphism was done using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for 83 pediatric kidney transplant recipients and 80 matched healthy controls.

RESULTS

In Multidrug resistant 1 gene (C3435T), CC, CT genotypes and C allele were significantly associated with risk of acute rejection when compared to none acute rejection group (P = 0.008, 0.001 and 0.01 respectively). The required tacrolimus doses to achieve trough level were significantly higher among CC than CT than TT genotypes through the 1st 6 months after kidney transplantation. While, in Multidrug resistant 1 gene (G2677T), GT, TT genotypes and T allele were associated with acute rejection when compared to none acute rejection (P = 0.023, 0.033 and 0.028 respectively). The required tacrolimus doses to achieve trough level were significantly higher among TT than GT than GG genotypes through the 1st 6 months after kidney transplantation.

CONCLUSION

The C allele, CC and CT genotypes of Multidrug resistant 1 gene (C3435T) and the T allele, GT and TT genotypes of Multidrug resistant 1 gene (G2677T) gene polymorphism may be risk factors for acute rejection and this can be attributed to their effect on tacrolimus pharmacokinetics. Tacrolimus therapy may be tailored according to the recipient genotype for better outcome.

Kidney-transplanted Adolescents-Nonadherence and Graft Outcomes During the Transition Phase: A Nationwide Analysis, 2000-2020

BACKGROUND

The transition from pediatric to young adult care is a vulnerable period for the renal transplant patient. We aimed to identify medication nonadherence (noninitiation, nonimplementation, and nonpersistence) and graft loss rates among adolescents and young adults and elucidate the influence of the transition phase on transplant outcomes.

METHODS

A retrospective nationwide cohort analysis of all renal transplantations in Norway from 2000 to 2020 was performed. Data were retrieved from the Norwegian Renal Registry, and adherence data from hospital charts. Patients transplanted aged <50 y, with functioning graft at 6 mo, were included. Recipients transplanted aged <26 y were compared with recipients transplanted aged 26-50 y. Graft loss, acute rejection, and development of de novo donor-specific antibodies were assessed in relation to the transition phase, defined as 14-26 y.

RESULTS

Data from 1830 kidney recipients were included: 371 (20%) transplanted <26 y (64% male, 68% living donor) versus 1459 transplanted 26-50 y (63% male, 44% living donor). There were 298 graft losses, 78 (21%) in the <26-y group versus 220 (15%) in the 26- to 50-y group. During the transition phase, 36 grafts were lost, 29 (81%) after transfer to the adult service. Medication nonadherence was the reason for 58% (21 of 36) of the losses during the transition phase, versus 12% (27 of 220) in the 26- to 50-y group ( P < 0.001). The 5-y graft survival rate was 89% (95% confidence interval, 85%-92%) and 94% (92%-95%), respectively ( P = 0.01).

CONCLUSIONS

Nonadherence was verified as the main cause of kidney graft loss in the transition phase.

Retroperitoneal kidney transplantation with liver and native kidney mobilization: a safe technique for pediatric recipients

BACKGROUND

Pediatric kidney transplant (KT) using larger, deceased or living donor adult kidneys can be challenging in the pediatric population due to limited space in the retroperitoneum. Liver and native kidney (L/NK) mobilization techniques can be used in smaller and younger transplant recipients to aid in retroperitoneal placement of the renal allograft. Here, we compare the clinical outcomes of pediatric retroperitoneal KT with and without L/NK mobilization.

METHODS

We retrospectively analyzed pediatric renal transplant recipients treated between January 2015 and May 2021. Donor and recipient demographics, intraoperative data, and recipient outcomes were included. Recipients were divided into two groups according to the surgical technique utilized: with L/NK mobilization (Group 1) and without L/NK mobilization (Group 2). Baseline variables were described using frequency distributions for categorical variables and means and standard errors for continuous variables. Tests of association with the likelihood of using L/NK mobilization were performed using standard χ2 tests, t tests, and the log-rank test.

RESULTS

Forty-six pediatric recipients were evaluated and categorized into Group 1 (n = 26) and Group 2 (n = 20). Recipients in Group 1 were younger (6.7 ± 0.8 years vs. 15. 3 ± 0.7, P < 0.001), shorter (109.5 ± 3.7 vs. 154.2 ± 3.8 cm, P < 0.001) and weighed less (21.4 ± 2.0 vs. 48.6 ± 3.4 kg, P < 0.001) than those in Group 2. Other baseline characteristics did not differ between Groups 1 and 2. One urologic complication was encountered in Group 2; no vascular or surgical complications were observed in either group. Additionally, no stents or drains were used in any of the patients. There were no cases of delayed graft function or graft primary nonfunction. The median follow-up of the study was 24.6 months post-transplant. Two patients developed death-censored graft failure (both in Group 2, P = 0.22), and there was one death with a functioning graft (in Group 2, P = 0.21).

CONCLUSIONS

Retroperitoneal liver/kidney mobilization is a feasible and safe technique that facilitates implantation of adult kidney allografts into pediatric transplant recipients with no increased risk of developing post-operative complications, graft loss, or mortality.

The Importance Of Avoiding Time-Dependent Bias When Testing The Prognostic Value Of An Intervening Event - Two Acute Cellular Rejection Examples In Intestinal Transplantation

In testing the prognostic value of the occurrence of an intervening event (clinical event that occurs post-transplant), 3 proper statistical methodologies for testing its prognostic value exist (time dependent covariate, landmark, and semi-Markov modelling methods). However, time-dependent bias has appeared in many clinical reports, whereby the intervening event is statistically treated as a baseline variable (as if it occurred at transplant). Using a single-center cohort of 445 intestinal transplant cases to test the prognostic value of 1^st acute cellular rejection (ACR) and severe (grade of) ACR on the hazard rate of developing graft loss, we demonstrate how the inclusion of such time-dependent bias can lead to severe underestimation of the true hazard ratio (HR). The (statistically more powerful) time dependent covariate method in Cox's multivariable model yielded significantly unfavorable effects of 1^st ACR (P<.0001; HR=2.492) and severe ACR (P<.0001; HR=4.531). In contrast, when using the time-dependent biased approach, multivariable analysis yielded an incorrect conclusion for the prognostic value of 1^st ACR (P=.31, HR=0.877, 35.2% of 2.492) and a much smaller estimated effect of severe ACR (P=.0008; HR=1.589; 35.1% of 4.531). In conclusion, this study demonstrates the importance of avoiding time-dependent bias when testing the prognostic value of an intervening event.

Dialysis in Israeli Children between 1990 and 2020: Trends and International Comparisons

BACKGROUND

Childhood kidney failure is a rare condition with worldwide clinical variability. We used a nationwide multicenter analysis to study the pretransplant course of the entire Israeli pediatric kidney failure population over 30 years.

METHODS

In this nationwide, population-based, historical cohort study, we analyzed medical and demographic data of all children treated with KRT and reported to the Israeli kidney failure registry in 1990-2020. Statistical analysis was performed with incidence rate corrected for age, ethnicity, and calendar year, using the appropriate age-related general population as denominator.

RESULTS

During the last 30 years, childhood incidence of kidney failure decreased. Average incidence in 2015-2019 was 9.1 cases per million age-related population (pmarp). Arab and Druze children exhibited higher kidney failure incidence rates than Jewish children (18.4 versus 7.0 cases pmarp for minorities versus Jews). The most common kidney failure etiologies among Arab and Jewish children were congenital anomalies of the kidney and urinary tract (approximately 27%), followed by cystic kidney diseases among Arab children (13%) and glomerulonephritis among Jewish children (16%). The most common etiology among Druze children was primary hyperoxaluria type 1 (33%). Israel's national health insurance provides access to primary health care to all citizens. Accordingly, waiting time for deceased-donor transplantation was equal between all ethnicities. Living-donor kidney transplantation rates among minority populations remained low in comparison with Jews over the entire study period. Although all patient groups demonstrated improvement in survival, overall survival rates were mainly etiology dependent.

CONCLUSIONS

In Israel, Arab and Druze children had a higher incidence of kidney failure, a unique etiological distribution, and a lower rate of living-donor kidney transplantations compared with Jewish children.

The kidney allocation system and pediatric transplantation at 5 years

BACKGROUND

A new Kidney Allocation System (KAS) was implemented in the United States in 2014 with the goal of improving equity and utility.

METHODS

In this study, we compare outcomes for kidney-alone candidates less than 18 years of age, at the time of listing, in the 5 years prior to and following policy implementation using Organ Procurement and Transplantation Network data.

RESULTS

While the pediatric deceased donor transplant rate increased under KAS, this increase was due solely to improved access for children aged 11-17 years; there was an 18.9% decrease in the deceased donor transplant rate among children 0-5 years old, from 117.94 to 95.8 transplants per 100 person-years (p = .001). The cumulative incidence of deceased donor transplantation by 1 year after listing decreased from 39.3% in the pre-KAS era to 35.5% in the post-KAS era (p = .004), a decline that was driven entirely by longer wait times for children 0-5 years old (p = .017). Candidates with a calculated panel reactive antibody of 98%-100% experienced a significant increase in transplant rate, but there was no change in transplant rate for Black or Hispanic candidates.

CONCLUSION

Overall, KAS increased transplantation access for teenaged and highly sensitized candidates but resulted in decreased access for the youngest children with no improvement in racial/ethnic equality.

Non-Immunologic Causes of Late Death-Censored Kidney Graft Failure: A Personalized Approach

Despite continuous advances in surgical and immunosuppressive protocols, the long-term survival of transplanted kidneys is still far from being satisfactory. Antibody-mediated rejection, recurrent autoimmune diseases, and death with functioning graft are the most frequent causes of late-kidney allograft failure. However, in addition to these complications, a number of other non-immunologic events may impair the function of transplanted kidneys and directly or indirectly lead to their failure. In this narrative review, we will list and discuss the most important nonimmune causes of late death-censored kidney graft failure, including quality of the donated kidney, adherence to prescriptions, drug toxicities, arterial hypertension, dyslipidemia, new onset diabetes mellitus, hyperuricemia, and lifestyle of the renal transplant recipient. For each of these risk factors, we will report the etiopathogenesis and the potential consequences on graft function, keeping in mind that in many cases, two or more risk factors may negatively interact together.

Transplantation Mediates Much of the Racial Disparity in Survival from Childhood-Onset Kidney Failure

BACKGROUND

The role of kidney transplantation in differential survival in Black and White patients with childhood-onset kidney failure is unexplored.

METHODS

We analyzed 30-year cohort data of children beginning RRT before 18 years of age between January 1980 and December 2017 (n=28,337) in the US Renal Data System. Cox regression identified transplant factors associated with survival by race. The survival mediational g-formula estimated the excess mortality among Black patients that could be eliminated if an intervention equalized their time with a transplant to that of White patients.

RESULTS

Black children comprised 24% of the cohort and their crude 30-year survival was 39% compared with 57% for White children (log rank P<0.001). Black children had 45% higher risk of death (adjusted hazard ratio [aHR], 1.45; 95% confidence interval [95% CI], 1.36 to 1.54), 31% lower incidence of first transplant (aHR, 0.69; 95% CI, 0.67 to 0.72), and 39% lower incidence of second transplant (aHR, 0.61; 95% CI, 0.57 to 0.65). Children and young adults are likely to require multiple transplants, yet even after their first transplant, Black patients had 11% fewer total transplants (adjusted incidence rate ratio [aIRR], 0.89; 95% CI, 0.86 to 0.92). In Black patients, grafts failed earlier after first and second transplants. Overall, Black patients spent 24% less of their RRT time with a transplant than did White patients (aIRR, 0.76; 95% CI, 0.74 to 0.78). Transplantation compared with dialysis strongly protected against death (aHR, 0.28; 95% CI, 0.16 to 0.48) by time-varying analysis. Mediation analyses estimated that equalizing transplant duration could prevent 35% (P<0.001) of excess deaths in Black patients.

CONCLUSIONS

Equalizing time with a functioning transplant for Black patients may equalize survival of childhood-onset ESKD with White patients.

Understanding disparities and barriers associated with pediatric transplant evaluation and time to listing: Moving toward a more comprehensive picture

BACKGROUND

Delayed time to listing (TTL) for pediatric transplant patients is associated with increased risks of mortality and morbidity. The full range of health disparities, sociodemographic factors, and other barriers associated with delays in listing in the pediatric transplant candidate evaluation process has not been fully examined.

METHODS

Retrospective chart reviews were conducted for 183 kidney, liver, and heart transplant candidates ages 0-18 who were referred for evaluation during 2012-2015. Demographic information and potential barriers (e g., social/medical factors, financial concerns) were gathered from pre-transplant evaluations and included in a comprehensive model to evaluate mechanisms that explain differences in TTL. Descriptive statistics, logistic regression models, Cox proportional hazards models, and path analysis were used for analyses.

RESULTS

Candidates included 26.8% heart, 33.3% liver, and 39.9% kidney patients. The most common barrier to listing was financial (71.6%), followed by caregiver psychological or substance use (57.9%), and medical problems (49.7%). Higher age, kidney, and liver organ type (relative to the heart), and presence of social, medical, administrative/motivation, and financial barriers were all directly associated with longer TTL. Public insurance was indirectly associated with TTL through social, administrative/motivation, and financial barriers. Organ type was indirectly associated with TTL through financial barriers.

CONCLUSIONS

Results suggest social problems, administrative issues, and financial issues act as mechanisms through which insurance type and liver transplant candidates face increased risk of delays in transplant listing time. There are numerous clinical implications and interventions that are warranted to reduce TTL among pediatric transplant candidates with co-occurring barriers.

Paediatric kidney transplantation in under-resourced regions-a panoramic view

Kidney transplantation is the ideal choice of kidney replacement therapy in children as it offers a low risk of mortality and a better quality of life. A wide variance in the access to kidney replacement therapies exists across the world with only 21% of low- and low-middle income countries (LLMIC) undertaking kidney transplantation. Pediatric kidney transplantation rates in these under-resourced regions are reported to be as low as < 4 pmcp [per million child population]. A robust kidney failure care program forms the cornerstone of a transplant program. Even the smallest transplant program entails a multidisciplinary workforce and expertise besides ensuring family commitment towards long-term care and economic burden. In general, the short-term graft survival rates from under-resourced regions are comparable to most high-income countries (HIC) and the challenge lies in the long-term outcomes. This review focuses on specific issues relevant to kidney transplants in children in under-resourced regions by highlighting limitations in the capacity and health workforce, regulatory norms, medical issues, economic burden, factors beyond financial hardship and ethical considerations relevant to these regions. Finally, the perspective of strengthening transplant programs in these regions should factor in the bigger challenges that exist in achieving the health-related sustainable development goals by 2030.

Extraperitoneal kidney transplantation: a comparison between children weighting ≤15 kg and >15 kg. Experience of a single institution

Extraperitoneal approach is sometimes recommended for kidney transplantation (KT) in children weighting <15 kg. We hypothesized that this approach might be as successful as in patients with normal weight. Data of all consecutive KTs performed between 2013 and 2019 were retrospectively reviewed. Early outcomes and surgical complications were compared between children weighing ≤15 kg (low‐weight (LW) group) and those weighing >15 kg (Normal‐weight (NW) group). All the 108 KTs were performed through an extraperitoneal approach. The LW group included 31 patients (mean age 3.5 ± 1.4 years), whose mean weight was 11.1 ± 2.0 kg. In the LW group,—a primary graft nonfunction (PNGF) occurred in one patient (3.2%), surgical complications occurred in nine (29%), with four venous thrombosis. In the NW group, PNGF occurred in one case (1.3%), delayed graft function (DGF) in eight (10%), surgical complications in 11 (14%) with only one case of venous thrombosis. In both groups, no need for patch during wound closure and no wound dehiscence were reported. The extraperitoneal approach can be effectively used in LW children. No differences were observed in the overall complication rate (P = 0.10), except for the occurrence of venous thrombosis (P = 0.02). This might be related to patients’ characteristics of the LW group.

The impact of multi-organ transplant allocation priority on waitlisted kidney transplant candidates

Kidney-alone transplant (KAT) candidates may be disadvantaged by the allocation priority given to multi-organ transplant (MOT) candidates. This study identified potential KAT candidates not receiving a given kidney offer due to its allocation for MOT. Using the Organ Procurement and Transplant Network (OPTN) database, we identified deceased donors from 2002 to 2017 who had one kidney allocated for MOT and the other kidney allocated for KAT or simultaneous pancreas-kidney transplant (SPK) (n = 7,378). Potential transplant recipient data were used to identify the "next-sequential KAT candidate" who would have received a given kidney offer had it not been allocated to a higher prioritized MOT candidate. In this analysis, next-sequential KAT candidates were younger (p < .001), more likely to be racial/ethnic minorities (p < .001), and more highly sensitized than MOT recipients (p < .001). A total of 2,113 (28.6%) next-sequential KAT candidates subsequently either died or were removed from the waiting list without receiving a transplant. In a multivariable model, despite adjacent position on the kidney match-run, mortality risk was significantly higher for next-sequential KAT candidates compared to KAT/SPK recipients (hazard ratio 1.55, 95% confidence interval 1.44, 1.66). These results highlight implications of MOT allocation prioritization, and potential consequences to KAT candidates prioritized below MOT candidates.

An Integrated Transcriptomic Approach to Identify Molecular Markers of Calcineurin Inhibitor Nephrotoxicity in Pediatric Kidney Transplant Recipients

Calcineurin inhibitors are highly efficacious immunosuppressive agents used in pediatric kidney transplantation. However, calcineurin inhibitor nephrotoxicity (CNIT) has been associated with the development of chronic renal allograft dysfunction and decreased graft survival. This study evaluated 37 formalin-fixed paraffin-embedded biopsies from pediatric kidney transplant recipients using gene expression profiling. Normal allograft samples (n = 12) served as negative controls and were compared to biopsies exhibiting CNIT (n = 11). The remaining samples served as positive controls to validate CNIT marker specificity and were characterized by other common causes of graft failure such as acute rejection (n = 7) and interstitial fibrosis/tubular atrophy (n = 7). MiRNA profiles served as the platform for data integration. Oxidative phosphorylation and mitochondrial dysfunction were the top molecular pathways associated with overexpressed genes in CNIT samples. Decreased ATP synthesis was identified as a significant biological function in CNIT, while key toxicology pathways included NRF2-mediated oxidative stress response and increased permeability transition of mitochondria. An integrative analysis demonstrated a panel of 13 significant miRNAs and their 33 CNIT-specific gene targets involved with mitochondrial activity and function. We also identified a candidate panel of miRNAs/genes, which may serve as future molecular markers for CNIT diagnosis as well as potential therapeutic targets.

Resident foreign patients receive adequate dialysis but fewer preemptive transplantations: data from the Italian pediatric dialysis registry

BACKGROUND

Sociocultural issues play a key role in children needing kidney replacement therapy (KRT).

METHODS

Data of incident patients < 18 years treated with chronic dialysis or preemptive kidney transplantation (pTx) between 2007 and 2016 were retrospectively collected from the Italian Pediatric Dialysis Registry; KRT modality and outcome were compared between patients with at least one non-Italian parent ("resident foreign patients," RFPs) and those from native parents ("domestic patients," DPs) and between the quinquennium 2007-2011 (period 1) and 2012-2016 (period 2).

RESULTS

We included 448 children (26.8% RFPs). The percentage of RFPs increased from 23 to 30.3% (p = 0.08) from periods 1 to 2. They were younger (6.7 vs. 9.4 years, p = 0.025) and less often treated with pTx (3.3 vs. 13.4%, p = 0.009) than DPs. The percentage of pTx increased from period 1 to 2 in RFPs only (8.4-18.6%, p = 0.006). Independent predictors of a lower probability of pTx were lower age, belonging to RFPs group, starting KRT in period 1 and focal segmental glomerulosclerosis or glomerulopathy as primary kidney disease. Peritoneal dialysis was the preferred dialysis modality in both groups. Age, primary kidney disease, and center size were independently associated with dialysis modality choice. Patient survival, waiting time to Tx, and dialysis modality survival were not different between the two groups.

CONCLUSIONS

The proportion of patients receiving KRT born from immigrant families increased in recent years in Italy. They were younger and less often treated with pTx than domestic patients. In case of dialysis, the outcome was not different between the two groups. Graphical abstract.

Glucose tolerance in a cohort of Egyptian children after kidney transplantation

BACKGROUND

Post- transplantation diabetes mellitus (PTDM) in children is a serious metabolic complication that can endanger both graft and patient survival. These complications can be partially reduced by early diagnosis & prompt treatment of impaired glucose tolerance. The aim of this study was to assess glucose tolerance & insulin resistance among a cohort of kidney transplanted children.

METHODS

Thirty consecutive pediatric kidney transplant recipients were subjected to basal evaluation of plasma glucose and insulin then underwent oral glucose tolerance test (OGTT).

RESULTS

Abnormal glucose metabolism was detected in 7 (23.3%) patients; 3 (10%) patients with PTDM; 3 (10%) patients with impaired fasting glucose (IFG) and 1 (3.3%) patient with IFG and impaired glucose tolerance (IGT). Four (13.3%) patients had high Homeostatic model assessment of insulin resistance (HOMA-IR). Patients with abnormal glucose metabolism had significantly higher tacrolimus trough levels and higher maintainence steroid doses (p values = 0.003,0.026). Significant positive correlation existed between pre-transplantation glucose level and post-transplantation fasting glucose (p = 0.001, r = 0.69), glucose at 120 min (p = 0.018, r = 0.429) and HOMA-IR (p = 0.008, r = 0.47).

CONCLUSION

Abnormalities in glucose metabolism (IFG, IGT &PTDM) are frequent in Egyptian pediatric kidney transplant recipients. OGTT is the gold standard for assessment of abnormalities in glucose metabolism.

Setting reasonable objectives for improving preemptive kidney transplantation rates in children

BACKGROUND

This study aims to develop a method to estimate the potential of preemptive kidney transplantation (PKT) by identifying patients who were transplanted after a dialysis period (non-preemptive kidney transplantation (NPKT)) despite being medically suitable for PKT.

METHODS

All children (< 18 years old) starting kidney replacement therapy (KRT) in France, between 2010 and 2016 and transplanted before December 31, 2017, were included. A propensity score (PS) of receiving PKT was estimated by multivariate logistic regression based on recipient medical characteristics. Healthcare use during the 24 months prior to KRT initiation was extracted from the French National Health Insurance database, and a pre-KRT follow-up of more than 18 months was considered sufficient to allow preemptive transplantation.

RESULTS

Among 643 patients who started KRT, 149 (23.2%) were preemptively transplanted. Using PS stratification, among 391 NPKT patients, we identified 145 patients (37%) suitable for PKT, according to clinical characteristics. Mean age was 12.3 years, 67% were males, and 56% had urological abnormalities. Among those 145 patients, we identified 79 NPKT patients who started on dialysis despite early referral to a nephrologist (more than 18 months prior to KRT initiation).

CONCLUSIONS

This method estimates a potential of 228 (149 + 79) PKT (35%) among pediatric patients in France. A similar method could be used in adults or in other countries. Estimation of the rate of patients with CKD stage 5 medically suitable for PKT will be of interest for health policy makers when setting up objectives for improvement in preemptive kidney transplant access.

Outcome of kidney transplantation from young pediatric donors (aged less than 6 years) to young size-matched recipients

INTRODUCTION

Pediatric donation is underutilized because of presumed increased risk of vascular thrombosis (VT) and graft loss. Using young pediatric donors (YPDs) for young pediatric recipients (YPRs) is suggested to be even at greater risk and therefore precluded in many centers. The aim of this study was to analyze the outcome of kidney transplantation (KT) from YPD to age-matched YPR.

PATIENT AND METHODS

A retrospective study of 118 pediatric KT performed between January 2007-July 2017. The authors identified KT with YPD (considered as those aged <6 years) and age-matched YPR. Organ allocation was performed based on the best paired size (YPR for YPR). Data were collected regarding donor and recipient characteristics, surgical and urological complications, graft loss, and outcomes.

RESULTS

Forty cases of YPD to age-matched YPR were identified (33.89% of the cohort). Mean recipient and donor age were 2.9 years (SD 1.68) and 2.24 years (SD 1.5), respectively. Mean recipient and donor weight were 12.7 kg (SD 4.1) and 13.7 kg (SD 4.15), respectively. Thirty of those young recipients (75%) weighed <15 kg. The most frequent primary renal disease was the congenital nephrotic syndrome. Nine out of 40 patients (22.5%) had received a previous KT before. Three received a combined liver-KT. Eight (20%) were classified as high immunological risk and 19 (47.5%) as high thrombotic risk. All allografts were implanted extraperitoneally and anastomosed to the iliac vessels. Major complications requiring reintervention occurred in seven patients (17.5%): three VT, three bleeding episodes, and one ureteral necrosis. Remarkably, only one surgical complication (VT) resulted in graft loss. Regarding long-term urological complications, four patients (10%) all with obstructive uropathy-developed vesicoureteral reflux to the graft. Actuarial graft survival at 1,5, and 10 years in the YPD to age-matched YPR cohort was 83% -78% -78%, respectively. Mean follow-up was 3.6 years (SD 3.2) (r = 7-10). Over time, eight patients lost their graft, not related to surgical factors in seven out of eight cases.

CONCLUSION

The authors suggest that KT using YPD for age-match YPR yields good results in expert centers, even in high-risk patients and is associated with good graft survival. In this series, surgical complications were rarely related to graft loss.

Living or deceased donor kidney transplantation in children

PURPOSE OF REVIEW

Kidney transplantation is the preferred treatment modality for children with end-stage renal disease. In this review, we discuss the factors affecting the selection of the appropriate donor to ensure the best possible short and long-term outcomes.

RECENT FINDINGS

Outcomes of pediatric renal transplantation from living donors are superior to those obtained from deceased donors. Despite this, the rate of living donor kidney transplantation has declined over the last decade. Living donation is considered to be safe but long-term outcomes, especially for parents who are often young donors, are not well understood. Living donation can also cause a financial impact to the donor and family. Barriers to living donation must be sought and defeated. Deceased donor organs are now the primary source of kidneys. How the risk of extended time on dialysis must be weighed against the improved outcomes that may accrue from better matching is controversial. Increasing the donor pool may be accomplished by reassessing sources that are currently avoided, such as donation after cardiac death and infant kidneys transplanted en bloc.

SUMMARY

The pediatric nephrologist must balance waiting for the highest quality kidney against the need for the shortest possible waiting time.

Composite Health Outcomes in Pediatric and Young Adult Kidney Transplant Recipients

OBJECTIVE

To assess composite health outcomes in pediatric and young adult kidney transplant recipients following kidney transplantation.

STUDY DESIGN

We conducted a cross-sectional study of all recipients at our center who had a 1-, 3-, 5-, and/or 10-year transplant anniversary visit between October 2008 and February 2015. The kidney transplant recipients were assessed at each time point according to an outcome measure consisting of 15 pass/fail criteria in 5 domains: allograft health, rejection and immunology, infection, cardiovascular health, and growth.

RESULTS

We analyzed 148 patients at 231 transplantation anniversary visit time points; 52 of 82 (63%) patients assessed at 1 year had an ideal outcome, meeting at least 13 of the 15 criteria. This decreased to 37% at year 3, 40% at year 5, and 26% at year 10 (P < .01). The most common failures across all time points occurred in the domains of growth (43%-52% passing) and cardiovascular health (33%-51% passing). Allograft health declined significantly, decreasing from 74% at year 1 to 33% at year 10 (P < .01). The percentage of patients with graft failure increased from 2.4% at 1 year to 39.5% at 10 years (P < .01), and patient deaths increased from 0 to 11% (P < .01) in the same time frame.

CONCLUSIONS

Ideal outcomes for pediatric kidney transplant recipients decrease over time with growth, cardiovascular health, and allograft health as the primary failure modes. Understanding the composite health of young recipients will allow primary care providers and nephrologists alike to evaluate the overall health of kidney transplant recipients and focus clinical care on the most common sequelae.

Recovery of Kidney Function in Children Treated with Maintenance Dialysis

BACKGROUND AND OBJECTIVES

Data on recovery of kidney function in pediatric patients with presumed ESKD are scarce. We examined the occurrence of recovery of kidney function and its determinants in a large cohort of pediatric patients on maintenance dialysis in Europe.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data for 6574 patients from 36 European countries commencing dialysis at an age below 15 years, between 1990 and 2014 were extracted from the European Society for Pediatric Nephrology/European Renal Association-European Dialysis and Transplant Association Registry. Recovery of kidney function was defined as discontinuation of dialysis for at least 30 days. Time to recovery was studied using a cumulative incidence competing risk approach and adjusted Cox proportional hazard models.

RESULTS

Two years after dialysis initiation, 130 patients (2%) experienced recovery of their kidney function after a median of 5.0 (interquartile range, 2.0-9.6) months on dialysis. Compared with patients with congenital anomalies of the kidney and urinary tract, recovery more often occurred in patients with vasculitis (11% at 2 years; adjusted hazard ratio [HR], 20.4; 95% confidence interval [95% CI], 9.7 to 42.8), ischemic kidney failure (12%; adjusted HR, 11.4; 95% CI, 5.6 to 23.1), and hemolytic uremic syndrome (13%; adjusted HR, 15.6; 95% CI, 8.9 to 27.3). Younger age and initiation on hemodialysis instead of peritoneal dialysis were also associated with recovery. For 42 patients (32%), recovery was transient as they returned to kidney replacement therapy after a median recovery period of 19.7 (interquartile range, 9.0-41.3) months.

CONCLUSIONS

We demonstrate a recovery rate of 2% within 2 years after dialysis initiation in a large cohort of pediatric patients on maintenance dialysis. There is a clinically important chance of recovery in patients on dialysis with vasculitis, ischemic kidney failure, and hemolytic uremic syndrome, which should be considered when planning kidney transplantation in these children.

Is donor age 6 years or less related to increased risk of surgical complications in pediatric kidney transplantation?

INTRODUCTION

Despite the widespread organ shortage dilemma, there is hesitancy regarding utilization of young donors (aged ≤6 years) because previous reports have suggested that this is associated with an increased risk of surgical complications and graft loss.

OBJECTIVE

The aim of this study was to determine if donor age ≤6 years is related to increased risk of surgical complications or allograft loss in pediatric kidney transplantation (KT).

STUDY DESIGN

A retrospective study of pediatric kidney transplants (KT) undertaken between January 2000 and July 2015. The incidence of surgical and urological complications, and allograft loss were analyzed and compared between donors aged ≤6 years (Group 1) and donors aged >6 years (Group 2).

RESULTS

A total of 171 pediatric KTs were performed at the current center during the study period. Twenty-eight patients were excluded; as a result, the study comprised 143 patients: 60 (Group 1) and 83 (Group 2). Mean recipient weight was 17 kg (SD 9.7; range 3.2-47) in Group 1 and 38.2 kg (SD 15.3; range 7.8-73) in Group 2. Despite a significantly higher proportion of risk factors in Group 1, no significant between-group differences were observed in terms of: surgical complications (OR 0.4; range 0.1-1.2), early urological complications (OR 2.2; range 0.4-11), late urological complications (OR 0.3; range 0.8-1.4), lymphoceles (OR 6.2; range 0.7-51.7) and allograft loss (OR 1.5; range 0.7-3.1, summary Table). Graft survival at 1 and 5 years was: 81% and 70% (Group 1) and 92% and 79% (Group 2), respectively (P = 0.093). Mean follow-up was 90.13 ± 49.7 months.

DISCUSSION

The main finding of this retrospective study was that pediatric donor kidneys from donors aged ≤6 years could safely be used in pediatric recipients without an increased risk of surgical and urological complications or graft loss. Nevertheless, KT with small donor kidneys is challenging and should be performed at experienced pediatric centers.

CONCLUSION

In line with these results, the outcomes of KT using donors aged ≤6 years were encouraging and similar to those obtained with older donors. Thus, this study supported using kidney grafts from young donors, given the organ shortage and potential high mortality risk while awaiting KT.

Why is transition between child and adult services a dangerous time for young people with chronic kidney disease? A mixed-method systematic review

Young people age 14-25 years with chronic kidney disease have been identified as generally having poor health outcomes and are a high-risk group for kidney transplant loss due in part to poor self-management. This raises a key question as to what happens during transition from child to adult services? This paper presents a mixed-method systematic review of health and social care evidence concerning young people with chronic kidney disease transitioning from child to adult health and social care services. Quantitative and qualitative evidence were synthesised in streams followed by an overarching synthesis. Literature searches (2000 to March 2017) were conducted using Pubmed, BioMed Central and Cochrane Library, grey literature sources ZETOC, .gov.uk, third sector organisations, NHS Evidence, SCIE, TRIP, Opengrey. Snowball searching was conducted in the databases Ovid, CINAHL, ISI Web of Science, Scopus and Google Scholar. Of 3,125 records screened, 60 texts were included. We found that while strategies to support transition contained consistent messages, they supported the principle of a health-dominated pathway. Well-being is mainly defined and measured in clinical terms and the transition process is often presented as a linear, one-dimensional conduit. Individual characteristics, along with social, familial and societal relationships are rarely considered. Evidence from young people and their families highlights transition as a zone of conflict between independence and dependency with young people feeling powerless on one hand and overwhelmed on the other. We found few novel interventions and fewer that had been evaluated. Studies were rarely conducted by allied health and social care professionals (e.g. renal social workers and psychologists) as part of multi-disciplinary renal teams. We conclude that there is a lack of good evidence to inform providers of health and social care services about how best to meet the needs of this small but vulnerable cohort.

Decreasing deceased donor transplant rates among children (≤6 years) under the new kidney allocation system

The Kidney Allocation System (KAS) was implemented in December 2014 with unknown impact on the pediatric waitlist. To understand the effect of KAS on pediatric registrants, deceased donor kidney transplant (DDKT) rate was assessed using interrupted time series analysis and time-to-event analysis. Two allocation eras were defined with an intermediary washout period: Era 1 (01/01/2013-09/01/2014), Era 2 (09/01/2014-03/01/2015), and Era 3(03/01/2015-03/01/2017). When using Cox proportional hazards, there was no significant association between allocation era and DDKT likelihood as compared to Era 1 (Era 3: aHR: 1.07, 95% CI: 0.97-1.18, P = .17). However, this was not consistent across all subgroups. Specifically, while highly sensitized pediatric registrants were consistently less likely to be transplanted than their less sensitized counterparts, this disparity was attenuated in Era 3 (Era 1 aHR: 0.04, 95%CI: 0.01-0.14, P < .001; Era 3 aHR: 0.33, 95% CI: 0.21-0.53, P < .001) whereas the youngest registrants aged 0-6 experienced a 21% decrease in DDKT likelihood in Era 3 as compared to Era 1 (aHR: 0.79, 95% CI: 0.64-0.98, P = .03). Thus, while overall DDKT likelihood remained stable with the introduction of KAS, registrants ≤ 6 years of age were disadvantaged, warranting further study to ensure equitable access to transplantation.

Outcome of renal transplantation in small infants: a match-controlled analysis

BACKGROUND

Infants with a body weight of less than 10 kg are often not considered to be suitable candidates for renal transplantation (RTx). The objective of this study was to evaluate this arbitrary weight threshold for pediatric RTx.

METHODS

We conducted a multicenter, retrospective, match-controlled cohort study on infants weighing less than 10 kg at time of engrafting (low-weight group [LWG], n = 38) compared to a matched control group (n = 76) with a body weight of 10-15 kg, using data from the first 2 years post-transplant derived from the CERTAIN Registry.

RESULTS

Patient survival was 97 and 100% in the LWG and control groups, respectively (P = 0.33), and death-censored graft survival was 100 and 95% in the LWG and control groups, respectively (P = 0.30). Estimated glomerular filtration rate at 2 years post-transplant was excellent and comparable between the groups (LWG 77.6 ± 34.9 mL/min/1.73 m²; control 74.8 ± 29.1 mL/min/1.73 m²; P = 0.68). The overall incidences of surgery-related complications (LWG 11%, control 23%; P = 0.12) and medical outcome measures (LWG 23%, control 36%, P = 0.17) were not significantly different between the groups. The medical outcome measures included transplant-related viral diseases (LWG 10%, control 21%; P = 0.20), acute rejection episodes (LWG 14%, control 29%; P = 0.092), malignancies (LWG 3%, control 0%; P = 0.33) and arterial hypertension (LWG 73%, control 67%; P = 0.57).

CONCLUSIONS

These data suggest that RTx in low-weight children is a feasible option, at least in selected centers with appropriate surgical and medical expertise.

The association of donor and recipient age with graft survival in paediatric renal transplant recipients in a European Society for Paediatric Nephrology/European Renal Association-European Dialysis and Transplantation Association Registry study

Background

The impact of donor age in paediatric kidney transplantation is unclear. We therefore examined the association of donor-recipient age combinations with graft survival in children.

Methods

Data for 4686 first kidney transplantations performed in 13 countries in 1990-2013 were extracted from the ESPN/ERA-EDTA Registry. The effect of donor and recipient age combinations on 5-year graft-failure risk, stratified by donor source, was estimated using Kaplan-Meier survival curves and Cox regression, while adjusting for sex, primary renal diseases with a high risk of recurrence, pre-emptive transplantation, year of transplantation and country.

Results

The risk of graft failure in older living donors (50-75 years old) was similar to that of younger living donors {adjusted hazard ratio [aHR] 0.74 [95% confidence interval (CI) 0.38-1.47]}. Deceased donor (DD) age was non-linearly associated with graft survival, with the highest risk of graft failure found in the youngest donor age group [0-5 years; compared with donor ages 12-19 years; aHR 1.69 (95% CI 1.26-2.26)], especially among the youngest recipients (0-11 years). DD age had little effect on graft failure in recipients' ages 12-19 years.

Conclusions

Our results suggest that donations from older living donors provide excellent graft outcomes in all paediatric recipients. For young recipients, the allocation of DDs over the age of 5 years should be prioritized.

Infection-related hospitalizations after kidney transplantation in children: incidence, risk factors, and cost

BACKGROUND

Infection is the leading cause of death and hospitalization in renal transplant recipients. We describe posttransplant infections requiring hospitalization, their risk factors and cost in a national pediatric kidney transplantation cohort.

METHODS

Data on renal transplant recipients <20 years were extracted from the French National Medicoadministrative Hospital Discharge database between 2008 and 2013 and matched with the Renal Transplant Database. We used Cox regression to study risk factors of hospitalization and calculated the instantaneous risk of hospitalization per month for all infections and by infection type.

RESULTS

Five hundred and ninety-three patients were included, and 660 infection-related hospitalizations were identified in 260 patients. The leading cause of hospitalization was urinary tract infection (UTI), followed by viral infection (16.6 and 15.6 per 100 person-years, respectively). Risk factors were younger age at transplantation, high number of HLA mismatches, and use cyclosporine rather than tacrolimus as first anticalcineurin treatment. Risk factors varied by infection type. Female gender, uropathy, cold ischemia time, and cyclosporine were associated with increased risk of UTI, while only age at transplantation inversely correlated with virus-related hospitalizations. Instantaneous risk of all infections decreased with time, except for cytomegalovirus (CMV) infection that displayed a peak at 6 months posttransplantation after prophylaxis withdrawal. Total cost of infection-related hospitalizations was 1600 kilo-euro (k€) (933 €/person-years).

CONCLUSIONS

This study highlights the high burden of infection in transplanted pediatric patients, especially the youngest. This should be considered both for pretransplantation information and designing procedures aiming to decrease hospitalization rate and duration.

Kidney transplantation in children weighing 15 kg or less is challenging but associated with good outcome

OBJECTIVE

Pediatric kidney transplantation (KT) in small children is assumed to be related to potential surgical complications that may cause severe morbidity and graft loss. The aim of our study was to analyze the outcome of KT recipients weighing ≤15 kg, focusing on surgical complications, associated morbidity and mortality, as well as allograft loss.

METHODS

We reviewed our retrospective institutional database for recipients of KT between January 2000 and December 2014 with body weight ≤15 kg.

RESULTS

Forty-four children weighing ≤15 kg, out of a total of 164 children (26.8%), received a deceased donor KT at our center during the study period. Mean weight was 10.10 ± 2.9 kg (3-15 kg), and weight was ≤10 kg in 23 patients (52.3%). The allograft was implanted intraperitoneally in two cases (4.5%) and extraperitoneally in the remaining 42 (95.5%). Two patients received a simultaneous double liver-kidney transplant. Postoperative complications appeared in 10 patients (22.7%) and eight required reintervention. Five allografts (11.4%) were lost secondary to surgical complications. No statistically significant differences in surgical complications were observed when compared with patients weighing >15 kg. Actuarial graft survival was 81% and 73% at 1 and 5 years, respectively. No significant differences in graft survival were observed compared with patients >15 kg. Mean follow-up was 84.95 ± 50 months (1-190 months).

CONCLUSIONS

Our results demonstrate that KT in children weighing ≤15 kg is challenging but not associated with increased risk of surgical complications or early graft loss.

Safety and Efficacy of Alemtuzumab Induction in Highly Sensitized Pediatric Renal Transplant Recipients

BACKGROUND

Studies show that alemtuzumab, a potent lymphocyte-depleting agent, is well tolerated in pediatric renal transplantation. We report on the use of alemtuzumab induction in highly HLA sensitized (HS) pediatric kidney transplant patients.

METHODS

Fifty pediatric renal transplants were performed from 1/2009-12/2014. 15 HS patients received IVIG (2 g/kg ×2 doses)/rituximab (375 mg/m ×1) for desensitization with alemtuzumab induction (15-30 mg, 1 dose, subcutaneous), whereas 35 nonsensitized patients received anti-IL-2R. Graft survival and infections were compared between 2 groups.

RESULTS

All HS patients had received a prior transplant and were older with lower risk for viral infections due to serostatus. Patient survival was 100%, and graft outcomes were similar with mean 1-year creatinine of 1.03 ± 0.45 versus 0.99 ± 0.6 (P = 0.48). Although a higher incidence of acute cellular rejection was seen in HS patients receiving alemtuzumab (P = 0.001), there was a nonsignificant difference in antibody-mediated rejection. White blood cell and absolute lymphocyte count were significantly lower in alemtuzumab group at 30 days (P < 0.0001) and at 1 year (P = 0.026 and P = 0.001), respectively. There was no significant difference in bacterial, viral, or fungal infections after transplant.

CONCLUSIONS

Alemtuzumab induction with desensitization led to nearly equivalent graft survival and functional outcomes in HS pediatric patients as nonsensitized patients receiving anti-IL-2R induction. With this small sample size, we observed significant reduction of white blood cell and absolute lymphocyte count up to 1 year posttransplant. The risk of infection was comparable between the 2 groups; however, patients who received alemtuzumab were older and at lower risk of viral infection due to serostatus.

Racial and Ethnic Disparities in Survival of Children with ESRD

Observational studies have reported that black and Hispanic adults receiving maintenance dialysis survive longer than non-Hispanic white counterparts. Whether there are racial disparities in survival of children with ESRD is not clear. We compared mortality risk among non-Hispanic black, Hispanic, and non-Hispanic white children who started RRT between 1995 and 2011 and were followed through 2012. We examined all-cause mortality using adjusted Cox models. Of 12,123 children included for analysis, 1600 died during the median follow-up of 7.1 years. Approximately 25% of children were non-Hispanic black, and 26% of children were of Hispanic ethnicity. Non-Hispanic black children had a 36% higher risk of death (95% confidence interval [95% CI], 1.21 to 1.52) and Hispanic children had a 34% lower risk of death (95% CI, 0.57 to 0.77) than non-Hispanic white children. Adjustment for transplant as a time-dependent covariate abolished the higher risk of death in non-Hispanic black children (hazard ratio, 0.99; 95% CI, 0.88 to 1.12) but did not attenuate the finding of a lower risk of death in Hispanic children (hazard ratio, 0.59; 95% CI, 0.51 to 0.68). In conclusion, Hispanic children had lower mortality than non-Hispanic white children. Non-Hispanic black children had higher mortality than non-Hispanic white children, which was related to differences in access to transplantation by race. Parity in access to transplantation in children and improvements in strategies to prolong graft survival could substantially reduce disparities in mortality risk of non-Hispanic black children treated with RRT.

Effects of acute rejection vs new-onset diabetes after transplant on transplant outcomes in pediatric kidney recipients: analysis of the Organ Procurement and Transplant Network/United Network for Organ Sharing (OPTN/UNOS) database

Improving long-term transplant and patient survival is still an ongoing challenge in kidney transplant medicine. Our objective was to identify the subsequent risks of new-onset diabetes after transplant (NODAT) and acute rejection (AR) in the first year post-transplant in predicting mortality and transplant failure. A total of 4687 patients without preexisting diabetes (age 2-20 years, 2004-2010) surviving with a functioning transplant for longer than 1 year with at least one follow-up report were identified from the OPTN/UNOS database as of September 2014. Study population was stratified into four mutually exclusive groups: Group 1, patients with a history of AR; Group 2, NODAT+; Group 3, NODAT+ AR+; and Group 4, the reference group (neither). Multivariate regression was used to analyze the relative risks for the outcomes of transplant failure and mortality. The median follow-up time was 1827 days after 1 year post-transplant. AR was associated with an increased risk of adjusted graft and death-censored graft failure (HR 2.87, CI 2.48-3.33, P < .001 and HR 2.11, CI 1.81-2.47, P < .001), respectively. NODAT and AR were identified in 3.5% and 14.5% of all study patients, respectively. AR in the first year post-transplant was a major risk factor for overall and death-censored graft failure, but not mortality. However, NODAT was not a risk factor on graft survival or mortality.

Gender Disparities in Access to Pediatric Renal Transplantation in Europe: Data From the ESPN/ERA-EDTA Registry

Inequalities between genders in access to transplantation have been demonstrated. We aimed to validate this gender inequality in a large pediatric population and to investigate its causes. This cohort study included 6454 patients starting renal replacement therapy before 18 years old, in 35 countries participating in the European Society for Paediatric Nephrology/European Renal Association-European Dialysis and Transplant Association Registry. We used cumulative incidence competing risk and proportional hazards frailty models to study the time to receive a transplant and hierarchical logistic regression to investigate access to preemptive transplantation. Girls had a slower access to renal transplantation because of a 23% lower probability of receiving preemptive transplantation. We found a longer follow-up time before renal replacement therapy in boys compared with girls despite a similar estimated glomerular filtration rate at first appointment. Girls tend to progress faster toward end-stage renal disease than boys, which may contribute to a shorter time available for pretransplantation workup. Overall, medical factors explained only 70% of the gender difference. In Europe, girls have less access to preemptive transplantation for reasons that are only partially related to medical factors. Nonmedical factors such as patient motivation and parent and physician attitudes toward transplantation and organ donation may contribute to this inequality. Our study should raise awareness for the management of girls with renal diseases.

Effect of Immigration Status on Outcomes in Pediatric Kidney Transplant Recipients

Kidney transplantation is the optimal treatment for children with end-stage renal disease. For children with undocumented immigration status, access to kidney transplantation is limited, and data on transplant outcomes in this population are scarce. The goal of the present retrospective single-center study was to compare outcomes after kidney transplantation in undocumented children with those of US citizen children. Undocumented residency status was identified in 48 (17%) of 289 children who received a kidney transplant between 1998 and 2010. In undocumented recipients, graft survival at 1 and 5 years posttransplantation was similar, and mean estimated glomerular filtration rate at 1 year was higher than that in recipients who were citizens. The risk of allograft failure was lower in undocumented recipients relative to that in citizens at 5 years posttransplantation, after adjustment for patient age, donor age, donor type, and HLA mismatch (p < 0.04). In contrast, nearly one in five undocumented recipients who reached 21 years of age lost their graft, primarily because they were unable to pay for immunosuppressive medications once their state-funded insurance had ended. These findings support the ongoing need for immigration policies for the undocumented that facilitate access to work-permits and employment-related insurance for this disadvantaged group.

Long-term effects of paediatric kidney transplantation

Renal transplantation in paediatric patients usually provides excellent short-term and medium-term results. Early diagnosis of chronic kidney disease and active therapy of end-stage renal disease before and after transplantation enables the majority of children to grow and develop normally. The adverse effects of immunosuppressive medication and reduced graft function might, however, hamper long-term outcomes in these patients and can lead to metabolic complications, cardiovascular disease, reduced bone health, and malignancies. The neurocognitive development and quality of life of paediatric transplant recipients largely depend on the primary diagnosis and on graft function. Poor adherence to immunosuppression is an important risk factor for graft loss in adolescents, and controlled transition to adult care is of utmost importance to ensure a continued normal life. In this Review, we discuss the outcomes and long-term effects of renal transplantation in paediatric recipients, including consequences on growth, development, bone, metabolic, and cardiovascular disorders. We discuss the key problems in the care of paediatric renal transplant recipients and the remaining challenges that should be the focus of future research.

Pediatric deceased donor renal transplantation: An approach to decision making I. Pediatric kidney allocation in the USA: The old and the new

Renal transplantation is the treatment of choice for children with end-stage renal disease. More than 50% of children receive a deceased donor renal transplant. Marked disparity between the number of children on the renal transplant wait list and the supply has prompted numerous advances to increase supply as well as maximize the utility of donor organs. Allocation of deceased donor kidneys is based on several criteria. The organ allocation system policy is continually evaluated and changed incrementally to optimize allocation. We, in the United States, are in the process of transitioning into a new kidney allocation system to enhance post-transplant survival benefit, increase utilization of donated kidneys, and increase transplant access for biologically disadvantaged candidates. This review will provide a brief overview of the organ sharing system in the United States, compare the "old" and the "new" allocation system, and discuss the considerations for the pediatric nephrologist while accepting a deceased donor kidney for a particular pediatric patient.

Outcome differences between young children and adolescents undergoing kidney transplantation

BACKGROUND/PURPOSE

Although graft loss remains the biggest challenge for all pediatric kidney transplant (KT) recipients, unique challenges exist within different age groups. We aim to evaluate the different characteristics and graft survival outcomes of young children and adolescents undergoing KT.

METHODS

Children who underwent isolated KT between 2000 and 2013 at our institution were included in this retrospective analysis. Patient characteristics and outcomes were compared using student's t-test, chi-square test, Kaplan-Meier curve and Cox proportional hazards model.

RESULTS

Of 73 children who underwent KT, 31 were <12 (young children), and 42 were ≥ 12 years old (adolescents). Overall patient survival was 100%. The younger group had superior 5-year (100% vs. 75.5%) and 10-year (94.4% vs. 43.8%) graft survival (p=0.008). Factors predictive of poor graft survival on multivariate analysis were older age at transplantation (HR 1.2, CI 1-1.4, p=0.047), female gender (HR 9.0, CI 1.9-43, p=0.006), and acute rejection episodes (HR 13, CI 2-90, p=0.008). The most common causes of graft loss were acute and chronic rejection episodes and immunosuppression nonadherence.

CONCLUSION

Adolescents undergoing KT have inferior graft survival compared to younger children. In adjusted modeling, children with older age, female gender, and acute rejection episodes have inferior graft survival.

The mortality risk with graft function has decreased among children receiving a first kidney transplant in the United States

Mortality has decreased in children with end stage kidney disease. Decreases in mortality during dialysis and improved graft survival contributed to this improvement. However, it is unknown if rates of death with graft function have also improved. We measured this in first transplant recipients under 21 years old registered in the USRDS. Cox models were used with a time-dependent renal replacement therapy modality variable to estimate the hazard ratios for death with graft function associated with a 1-year increment in the calendar year of transplant. There were 157,201 person-years of observation among 17,468 recipients with 82.2% of study time during graft function and 17.8% during dialysis after graft failure. There were 2003 deaths (12.7 deaths/1000 person-years) overall of which 985 occurred with graft function (7.6 deaths/1000 person-years) and 1018 occurred during dialysis after graft failure (36.1 deaths/1000 person-years). Each 1-year increment in calendar year of first transplant was associated with a significantly lower risk of death, both over all observation (HR 0.97 [0.96, 0.98]) and focusing on time with graft function (HR 0.98 [0.97, 0.99]). Living donation was significantly associated with better survival while dialysis after graft failure was associated with a much higher mortality risk (HR 4.85 [4.40, 5.35]) compared with graft function. Thus, the risk of death with graft function has decreased in children receiving a first kidney transplant. Increasing living donation and minimizing dialysis may further improve outcomes.