The impact of changing practice on improved outcomes of paediatric renal transplantation in the United Kingdom: a 25 years review

Pharmacokinetics of Envarsus in pediatric kidney transplant recipients - phase 1 pilot conversion study

INTRODUCTION

Tacrolimus is the standard immunosuppressant for pediatric kidney transplants and is routinely administered twice daily (BD-tac). Envarsus (LCP-tac), an extended-release formulation, is approved for adults but not for pediatric patients.

METHODS

We conducted a pilot open-label phase 1 study in stable pediatric kidney transplant recipients (age < 18 at the time of study). Our primary objective was to compare the pharmacokinetics (Pk) of LCP-tac versus BD-tac. We conducted two 24-h Pk studies: pre-conversion (BD-tac) and 4 weeks post-conversion to LCP-tac. Patients were followed for 6 months, with the option to continue LCP-tac.

RESULTS

Five patients completed the study, with no returns to BD-tac. Median age was 15 years (range 11-17). LCP-tac exhibited an extended-release profile versus the bimodal profile of BD-tac. Time to maximum concentration was delayed (5 h vs. 1 h), and maximum concentration was lower (9.9 ng/mL vs. 14.4 ng/mL). Tacrolimus area under the curve (24 h) was comparable (141 ± 46.5 ng/mL vs. 164 ± 27.8 ng/mL). No new safety concerns arose. There were no rejection and no difference in eGFR at the study's end (1.5 mL/min/1.73 m2 , range - 1.7 to 2.3 mL/min/1.73 m2 ). Concentration/dose ratio was higher in LCP-tac (1.8 ± 0.64 vs. 0.8 ± 0.39). The final conversion ratio was 0.6 (BD-tac: LCP-tac).

CONCLUSION

Our pilot study confirms the extended-release Pk profile and improved absorption of LCP-tac compared to BD-tac. A larger study is needed to further evaluate the population Pk characteristics in children.

Time-Varying Determinants of Graft Failure in Pediatric Kidney Transplantation in Europe

BACKGROUND

Little is known about the time-varying determinants of kidney graft failure in children.

METHODS

We performed a retrospective study of primary pediatric kidney transplant recipients (younger than 18 years) from the Eurotransplant registry (1990-2020). Piece-wise exponential additive mixed models were applied to analyze time-varying recipient, donor, and transplant risk factors. Primary outcome was death-censored graft failure.

RESULTS

We report on 4528 kidney transplantations, of which 68% with deceased and 32% with living donor. One thousand six hundred and thirty-eight recipients experienced graft failure, and 168 died with a functioning graft. Between 2011 and 2020, the 5-year graft failure risk was 10% for deceased donor and 4% for living donor kidney transplant recipients. Risk of graft failure decreased five-fold from 1990 to 2020. The association between living donor transplantation and the lower risk of graft failure was strongest in the first month post-transplant (adjusted hazard ratio, 0.58; 95% confidence interval, 0.46 to 0.73) and remained statistically significant until 12 years post-transplant. Risk factors for graft failure in the first 2 years were deceased donor younger than 12 years or older than 46 years, potentially recurrent kidney disease, and panel-reactive antibody >0%. Other determinants of graft failure included dialysis before transplantation (until 5 years post-transplant), human leukocyte antigen mismatch 2-4 (0-15 years post-transplant), human leukocyte antigen mismatch 5-6 (2-12 years post-transplant), and hemodialysis (8-14 years post-transplant). Recipients older than 11 years at transplantation had a higher risk of graft failure 1-8 years post-transplant compared with other age groups, whereas young recipients had a lower risk throughout follow-up. Analysis of the combined effect of post-transplant time and recipient age showed a higher rate of graft failure during the first 5 years post-transplant in adolescents compared with young transplant recipients. In contrast to deceased donor younger than 12 years, deceased donor older than 46 years was consistently associated with a higher graft failure risk.

CONCLUSIONS

We report a long-term inverse association between living donor kidney transplantation and the risk of graft failure. The determinants of graft failure varied with time. There was a significant cumulative effect of adolescence and time post-transplant. The ideal donor age window was dependent on time post-transplant.

Outcomes of pediatric deceased donor kidney transplant in northeast Thailand

BACKGROUND

Kidney transplantation (KT) is the best therapy in children with end-stage renal disease (ESRD), however, improving long-term graft survival remains challenging. The aim of this study was to determine graft survival and potential risk factors in pediatric patients who undergo deceased donor KT with a steroid-based regimen.

METHODS

The medical records of children who underwent their first deceased donor KT in Srinagarind Hospital (Khon Kaen, Thailand) between 2001 and 2020 were reviewed.

RESULTS

Seventy-two patients were studied. Male adolescents were the predominant recipients and the majority of donors were young adult males. Non-glomerular disease, particularly hypoplastic/dysplastic kidney disease, was the major cause of ESRD (48.61%). The mean cold ischemic time (CIT) was 18.29 ± 5.29 h. Most of the recipients had more than 4 human leukocyte antigen (HLA) mismatched loci with positive HLA-DR mismatch (52.78%). Induction therapy was administered in 76.74% of recipients. Tacrolimus plus mycophenolate sodium and prednisolone was the most common immunosuppressive maintenance regimen (69.44%). Graft failure occurred in 18 patients, mostly due to graft rejection (50%). Graft survival at 1, 3, and 5 years after KT were 94.40%, 86.25%, and 74.92%, respectively. The only significant risk factor of graft failure in this study was delayed graft function (DGF) (adjusted HR = 3.55; 95%CI: 1.14, 11.12; p = .029). Patient survival at 1, 3, and 5 years was 100%, 98.48%, and 96.19%, respectively.

CONCLUSION

The short-term outcomes of pediatric KT from deceased donors were satisfactory; however, prevention of DGF would result in better outcomes.

Long term outcomes following kidney transplantation in children who weighed less than 15 kg - report from the UK Transplant Registry

BACKGROUND

Kidney transplantation is the treatment of choice in chronic kidney disease (CKD) stage 5. It is often delayed in younger children until a target weight is achieved due to technical feasibility and historic concerns about poorer outcomes.

METHODS

Data on all first paediatric (aged < 18 years) kidney only transplants performed in the United Kingdom between 1 January 2006 and 31 December 2016 were extracted from the UK Transplant Registry (n = 1,340). Children were categorised by weight at the time of transplant into those < 15 kg and those ≥ 15 kg. Donor, recipient and transplant characteristics were compared between groups using chi-squared or Fisher's exact test for categorical variables and Kruskal-Wallis test for continuous variables. Thirty day, one-year, five-year and ten-year patient and kidney allograft survival were compared using the Kaplan-Meier method.

RESULTS

There was no difference in patient survival following kidney transplantation when comparing children < 15 kg with those ≥ 15 kg. Ten-year kidney allograft survival was significantly better for children < 15 kg than children ≥ 15 kg (85.4% vs. 73.5% respectively, p = 0.002). For children < 15 kg, a greater proportion of kidney transplants were from living donors compared with children ≥ 15 kg (68.3% vs. 49.6% respectively, p < 0.001). There was no difference in immediate graft function between the groups (p = 0.54) and delayed graft function was seen in 4.8% and 6.8% of children < 15 kg and ≥ 15 kg respectively.

CONCLUSIONS

Our study reports significantly better ten-year kidney allograft survival in children < 15 kg and supports consideration of earlier transplantation for children with CKD stage 5. A higher resolution version of the Graphical abstract is available as Supplementary information.

Life after a pediatric kidney transplant

INTRODUCTION AND OBJECTIVES

There is currently no doubt that a kidney transplant with good function is the best treatment we can offer a child with severe kidney failure, improving their growth, development and life in general. But there are few works that follow these patients over the years to find out what their life is like as adults, their achievements and if there are any difficulties that may have arisen from their illness. That has been the objective of this work.

MATERIAL AND METHODS

We have collected the evolution of 287 patients who received at least one kidney transplant in pediatric age, analyzing not only the survival of grafts and recipients but, fundamentally, their current quality of life.

RESULTS

Over a 40-year period (1979-2019), 345 kidney transplants were performed in 287 pediatric recipients, with a rate of retransplantation before reaching the age of majority of 16.7%. Survival, both of patients and grafts, has improved remarkably in the last 20 years. The survival of transplanted patients in the period from 1979 to 1996 at 10, 20 and 25 years after the intervention was 83%, 76% and 65% respectively, and 94% and 82% at 10 and 20 years respectively in those transplanted in the period from 1997 to 2019. Graft survival in the period from 1979 to 1996 at 10 and 20 years was 39% and 18%, increasing in the second period to 68% and 34% respectively. Survival of the first living donor graft (LD) at 5 and 10 years was 94% and 89%. Currently 150 of these patients are adults. Of these, 32% have a stable partner and 6.6% have children. The level of training is lower than that of the general population and many of them have other comorbidities.

CONCLUSIONS

The life expectancy of pediatric patients with kidney failure transplanted during childhood has improved markedly in recent decades, as has graft survival, being better with a living donor. In general, they consider themselves satisfied with their lives, with great acceptance of their illness and limitations, but -analyzing their testimonies- we conclude that they lack social support, both for themselves and their families, to achieve a higher level of education and better quality of life.

The UK kidney donor risk index poorly predicts long-term transplant survival in paediatric kidney transplant recipients

Background

The UK kidney offering scheme introduced a kidney donor risk index (UK-KDRI) to improve the utility of deceased-donor kidney allocations. The UK-KDRI was derived using adult donor and recipient data. We assessed this in a paediatric cohort from the UK transplant registry.

Methods

We performed Cox survival analysis on first kidney-only deceased brain-dead transplants in paediatric (<18 years) recipients from 2000-2014. The primary outcome was death-censored allograft survival >30 days post-transplant. The main study variable was UK-KDRI derived from seven donor risk-factors, categorised into four groups (D1-low risk, D2, D3 and D4-highest risk). Follow-up ended on 31-December-2021.

Results

319/908 patients experienced transplant loss with rejection as the main cause (55%). The majority of paediatric patients received donors from D1 donors (64%). There was an increase in D2-4 donors during the study period, whilst the level of HLA mismatching improved. The KDRI was not associated with allograft failure. In multi-variate analysis, increasing recipient age [adjusted HR and 95%CI: 1.05(1.03-1.08) per-year, p<0.001], recipient minority ethnic group [1.28(1.01-1.63), p<0.05), dialysis before transplant [1.38(1.04-1.81), p<0.005], donor height [0.99 (0.98-1.00) per centimetre, p<0.05] and level of HLA mismatch [Level 3: 1.92(1.19-3.11); Level 4: 2.40(1.26-4.58) versus Level 1, p<0.01] were associated with worse outcomes. Patients with Level 1 and 2 HLA mismatches (0 DR +0/1 B mismatch) had median graft survival >17 years regardless of UK-KDRI groups. Increasing donor age was marginally associated with worse allograft survival [1.01 (1.00-1.01) per year, p=0.05].

Summary

Adult donor risk scores were not associated with long-term allograft survival in paediatric patients. The level of HLA mismatch had the most profound effect on survival. Risk models based on adult data alone may not have the same validity for paediatric patients and therefore all age-groups should be included in future risk prediction models.

Use of organs from increased infectious risk deceased donors in pediatric kidney transplantation

Living donors are the main source of transplanted kidneys for children and young people in many countries, but there still remains a significant need for deceased donor kidney transplantation. Given the waiting times associated with deceased donor kidney transplantation and the morbidity or mortality that can occur in those on the waiting list, it is essential that the utilization of kidneys from deceased donors is optimized. The use of organs from deceased donors at increased risk of transmitting human immunodeficiency virus, hepatitis B virus, or hepatitis C virus is relatively common in adults, but far less so in children. The risks and benefits of the use of kidneys from increased infectious risk donors (IIRD) are discussed. The variation of definitions of IIRD between countries is explored as is the need for pediatric nephrologists and transplant surgeons to have an understanding of the prevalence of viral diseases within the country in which they work. The role of screening tests such as nucleic acid tests is examined, along with the concept of residual risk. Finally, considerations in acquiring informed consent in the use of kidneys from IIRDs in children and young people are discussed.

Perioperative fluid management and associated complications in children receiving kidney transplants in the UK

BACKGROUND

Intravenous fluid administration is an essential part of perioperative care for children receiving a kidney transplant. There is a paucity of evidence to guide optimal perioperative fluid management. This study aimed to identify the volume of perioperative fluids administered across 5 UK paediatric kidney transplant centres and explore associations between fluid volume administered, graft function, and fluid-related adverse events.

METHODS

Data were collected from five UK paediatric kidney transplant centres on perioperative fluid volumes administered, and incidence of pulmonary oedema, systemic hypertension, and requirement for intensive care support. Children < 18 years of age who received a kidney-only transplant between 1^st January 2020 and 31^st December 2021 were included.

RESULTS

Complete data from 102 children were analysed. The median total volume of fluid administered in 72 h was 377 ml/kg (IQR 149 ml/kg) with a high degree of variability. A negative relationship between total fluid volume administered and day 7 eGFR was noted (p < 0.001). Association between urine volume post-transplant and day 7 eGFR was also negative (p < 0.001). Adverse events were frequent but no significant difference was found in the fluid volume administered to those who developed an adverse event, vs those who did not.

CONCLUSIONS

This study describes a high degree of variability in perioperative fluid volumes administered to children receiving kidney transplants. Both fluid volume and urine output were negatively associated with short-term graft function. These data contrast traditional interpretation of high urine output as a marker of graft health, and highlight the need for prospective clinical trials to optimise perioperative fluid administration for this group. A higher resolution version of the Graphical abstract is available as Supplementary information.

EBV, CMV, and BK viral infections in pediatric kidney transplantation: Frequency, risk factors, treatment, and outcomes

BACKGROUND

Improved short- and long-term outcomes of kidney transplantation have been achieved over the past decades due to improved immunosuppression. This may have increased the risk for infections and, particularly, for the viral infections: cytomegalovirus (CMV), Epstein-Barr virus (EBV), and polyoma BK virus (BKV).

METHODS

A retrospective review of viremic CMV, EBV, and BKV infections in pediatric renal transplant recipients treated and followed by a national referral center over a 10-year period.

RESULTS

Sixty-seven patients (68% males) received 68 kidney grafts (62% from living donors) during the study period; the mean follow-up period was 5.2 ± 2.4 years. Twenty-seven viremic episodes were documented (CMV: 13, EBV: 6, BKV: 8) in 24 patients (35.2%). The median time (interquartile range) to viremia post-transplant was 11 (4-38) months. The viral infection rate was significantly higher in the years 2014-2015 than in previous years (61% vs. 29%, p = .017). Compared to patients who did not develop viremia, patients with viremias were younger at the time of transplantation, were more likely to receive thymoglobulin induction pre-transplant and to develop an acute rejection. Multiple logistic regression modeling identified transplant year and recipient's age as significant risk factors for viremia. Graft outcome and eGFR at the last follow-up was similar between patients who did and did not develop viremia.

CONCLUSIONS

Viral infections continue to be a major cause of morbidity in pediatric kidney transplant recipients. However, with close monitoring and prompt intervention, patient and renal outcomes remain favorable.

Long-Term Care of the Pediatric Kidney Transplant Recipient

Pediatric kidney transplant recipients are distinguished from adult recipients by the need for many decades of graft function, the potential effect of CKD on neurodevelopment, and the changing immune environment of a developing human. The entire life of an individual who receives a transplant as a child is colored by their status as a transplant recipient. Not only must these young recipients negotiate all of the usual challenges of emerging adulthood (transition from school to work, romantic relationships, achieving independence from parents), but they must learn to manage a life-threatening medical condition independently. Regardless of the age at transplantation, graft failure rates are higher during adolescence and young adulthood than at any other age. All pediatric transplant recipients must pass through this high-risk period. Factors contributing to the high graft failure rates in this period include poor adherence to treatment, potentially exacerbated by the transfer of care from pediatric- to adult-oriented care providers, and perhaps an increased potency of the immune response. We describe the characteristics of pediatric kidney transplant recipients, particularly those factors that may influence their care throughout their lives. We also discuss the risks associated with the transition from pediatric- to adult-oriented care and provide some suggestions to optimize the transition to adult-oriented transplant care and long-term outcomes.

Improve in-depth immunological risk assessment to optimize genetic-compatibility and clinical outcomes in child and adolescent recipients of parental donor kidney transplants: protocol for the INCEPTION study

Background

Parental donor kidney transplantation is the most common treatment option for children and adolescents with kidney failure. Emerging data from observational studies have reported improved short- and medium-term allograft outcomes in recipients of paternal compared to maternal donors. The INCEPTION study aims to identify potential differences in immunological compatibility between maternal and paternal donor kidneys and ascertain how this affects kidney allograft outcomes in children and adolescents with kidney failure.

Methods

This longitudinal observational study will recruit kidney transplant recipients aged ≤18 years who have received a parental donor kidney transplant across 4 countries (Australia, New Zealand, United Kingdom and the Netherlands) between 1990 and 2020. High resolution human leukocyte antigen (HLA) typing of both recipients and corresponding parental donors will be undertaken, to provide an in-depth assessment of immunological compatibility. The primary outcome is a composite of de novo donor-specific anti-HLA antibody (DSA), biopsy-proven acute rejection or allograft loss up to 60-months post-transplantation. Secondary outcomes are de novo DSA, biopsy-proven acute rejection, acute or chronic antibody mediated rejection or Chronic Allograft Damage Index (CADI) score of > 1 on allograft biopsy post-transplant, allograft function, proteinuria and allograft loss. Using principal component analysis and Cox proportional hazards regression modelling, we will determine the associations between defined sets of immunological and clinical parameters that may identify risk stratification for the primary and secondary outcome measures among young people accepting a parental donor kidney for transplantation. This study design will allow us to specifically investigate the relative importance of accepting a maternal compared to paternal donor, for families deciding on the best option for donation.

Discussion

The INCEPTION study findings will explore potentially differential immunological risks of maternal and paternal donor kidneys for transplantation among children and adolescents. Our study will provide the evidence base underpinning the selection of parental donor in order to achieve the best projected long-term kidney transplant and overall health outcomes for children and adolescents, a recognized vulnerable population.

Trial registration

The INCEPTION study has been registered with the Australian New Zealand Clinical Trials Registry, with the trial registration number of ACTRN12620000911998 (14th September 2020).

Demographics and long-term outcomes of children with end-stage kidney disease: A 20-year territory-wide study

AIM

To evaluate the demographics and long-term patient outcomes of children with end-stage kidney disease in Hong Kong.

METHODS

We conducted a cohort study at the Paediatric Nephrology Centre, the designated site providing kidney replacement therapy (KRT) for children in Hong Kong. The clinical characteristics and outcomes of all children who initiated chronic KRT before 19 years, between 2001 and 2020, were analysed.

RESULTS

One hundred forty-seven children (50% male) received KRT at a mean age of 11.4 ± 5.7 years. The incidence of ESKD was 6.28 per million age-related population (pmarp). The leading cause of ESKD was congenital anomalies (33%). Ten children (7%) had pre-emptive kidney transplants, 104 (71%) and 33 (22%) patients received automated peritoneal dialysis and haemodialysis as initial KRT. The incidence of ESKD increased over time, and were 4.38, 5.07, 6.15 and 9.17 pmarp during 2001-2005, 2006-2010, 2011-2015 and 2016-2020, respectively (p = .005). Ninty-seven patients (66%) received kidney transplants and the median time to receive a kidney graft was 3.7 years (95% CI 3.1-4.3). Only 10 patients had pre-emptive kidney transplants. The mortality rate was 9.1 deaths per 1000-patient-years (95%CI 4.6-16.2). The survival probabilities at 1-, 5-, 10- and 15-year were 100%, 94.8% (95%CI 90.7-98.9%), 89.7% (95% CI 83.4%-95.9%), 87.1% (95% CI 79.3%-94.9%), respectively. Standardised mortality ratio was 54.5. 72% of deaths were due to infections. Young infants and those without kidney transplants were associated with worse survival (p < .01). Multivariate analysis demonstrated that dialysis was the only factor associated with significantly increased risk of death (HR_adj 12.9, 95% CI 2.7-63.2, p = .002).

CONCLUSION

We observed an increasing incidence of paediatric ESKD in Hong Kong with considerable waiting time to kidney transplant. Mortality risk is comparable to other developed countries and is highest among dialysis population. Efforts should be made to facilitate early access to paediatric kidney transplantation in Hong Kong.

CMV, EBV, JCV and BKV infection and outcome following kidney transplantation in children initiated on a corticosteroid-minimisation immunosuppressive regimen

BACKGROUND

Modern immunosuppressive regimens in paediatric kidney transplant recipients have contributed to improved long-term allograft survival, but at the expense of an increased incidence of viral infections. Here, we describe, for the first time, the incidence, risk factors and clinical outcome of CMV, EBV, BKV and JCV viraemia in a cohort of paediatric allograft recipients treated with a corticosteroid-minimisation immunosuppressive regimen (CMR).

METHODS

We retrospectively analysed 98 children treated with a CMR (basiliximab induction, corticosteroids until day 4, long-term tacrolimus and mycophenolate mofetil), who received a kidney transplant in our centre between 2009 and 2019.

RESULTS

Over the first 4 years post-transplant, the incidences of viraemia were as follows: CMV, 25.5%; EBV, 52.0%; JCV, 16.3%; BKV, 26.5%. Younger children at time of transplant were more likely to develop EBV and BKV viraemia. EBV viraemia was also associated with a regimen involving corticosteroids, but lacking MMF. Recipient CMV serology predicted the development of EBV, BKV and CMV viraemia. Fifty-six percent of CMV viraemia episodes in high-risk patients occurred whilst the graft recipients were still receiving anti-viral prophylaxis or within 3 months of cessation. There was no difference in graft function at latest follow-up between those with and without viraemia.

CONCLUSIONS

Judicious monitoring of viraemia, coupled with timely clinical intervention, can result in similar long-term outcomes for graft recipients compared to controls. The high incidence of CMV viraemia observed within a short period of cessation of anti-viral prophylaxis supports an extension of the length of prophylactic treatment in high-risk allograft recipients.

Fluid overload and renal function in children after living-donor renal transplantation: a single-center retrospective analysis

BACKGROUND

We aimed to compare renal function after kidney transplantation in children who were treated with higher vs. lower fluid volumes.

METHODS

A retrospective analysis of 81 living-donor renal transplantation pediatric patients was performed between the years 2007 and 2018. We analyzed associations of the decrease in serum creatinine (delta creatinine) with fluid balance, central venous pressure (CVP), pulmonary congestion, mean arterial pressure (MAP), and MAP-CVP percentiles in the first 3 postoperative days. After correcting creatinine for fluid overload, we also assessed associations of these variables with the above parameters. Finally, we evaluated the association between delta creatinine and estimated glomerular filtration rate (eGFR) at 3 months follow-up.

RESULTS

Both delta creatinine and delta-corrected creatinine were found to be associated with pulmonary congestion on the second and third postoperative days (p < 0.02). In addition, trends for positive correlations were found of delta creatinine with fluid balance/kg (p = 0.07), and of delta-corrected creatinine with fluid balance/kg and CVP (p = 0.06-0.07) on the second postoperative day. An association was also demonstrated between the accumulated fluid balance of the first 2 days and eGFR at 3 months after transplantation (p = 0.03).

CONCLUSIONS

An association was demonstrated between indices of fluid overload, >80 ml/kg, and greater improvement in renal function.

IMPACT

There is no consensus regarding the optimal fluid treatment after pediatric renal transplantation. In our cohort, indices of fluid overload were associated with better renal function immediately after the transplantation and 3 months thereafter. Fluid overload after living-donor renal transplantation in children may have short- and long-term benefits on renal function.

Paediatric deceased donor kidney transplant in Australia: A 30-year review-What have paediatric bonuses achieved and where to from here?

BACKGROUND

In this 30-year national review, we describe trends in DD transplantation for paediatric recipients, assess the impact of paediatric allocation bonuses and identify outstanding areas of need for this population.

METHODS

A retrospective review of all DD kidney only transplants to paediatric recipients (<18 years old) in Australia between 1989 and 2018 was conducted using deidentified extracts from the ANZDATA.

RESULTS

Of the 1011 kidney only transplants performed in paediatric recipients during the study period, 426 (42%) were from deceased donors. Paediatric candidates on the DD waiting list had consistently higher rates of transplantation and shorter time from dialysis initiation to transplantation compared with adult candidates (median 372 vs 832 days in 2018, for example). Donor characteristics remained more favourable for paediatric recipients, despite a decline in the overall quality of the donor pool. The mean number of HLA antigen mismatches for paediatric recipients of DD transplants increased each decade (2.86 [1989-1998], 3.85 [1999-2008], 4.01 [2009-2018]). Both patient and graft survival have improved for paediatric DD transplant recipients in the most recent era (5-year graft and patient survival 85% vs 65% and 99% vs 94%, respectively, for 2009-2018 vs 1999-2008).

CONCLUSIONS

The current DD kidney allocation system in Australia provides rapid access to high-quality organs for paediatric recipients, and early graft loss has decreased significantly in recent years; however, additional targeted interventions to address HLA matching may improve long-term outcomes in this population.

Acute rejection and growth outcomes in paediatric kidney allograft recipients treated with a corticosteroid minimisation immunosuppressive protocol

BACKGROUND

Corticosteroid minimisation immunosuppressive protocols (CMP) for children are an approach to safely reduce unwanted medication side effects associated with long-term exposure following kidney transplantation. Here, we provide data regarding the incidence of acute rejection and growth over an extended follow-up in children receiving the CMP used in our centre.

METHODS

We retrospectively analysed all children treated with a CMP who received a kidney transplant and had follow-up care in our centre between 2009 and 2019. Data were compared to 5 control groups from recent studies.

RESULTS

Ninety-nine kidney allograft recipients were included in the study (mean follow-up 4.4 years). There was no difference in the cumulative frequency of acute rejection in CMP-treated graft recipients compared to controls. Graft function at latest follow-up was significantly lower in graft recipients experiencing acute rejection compared to those without acute rejection (53.7 mL/min/1.73 m² vs. 66.8 mL/min/1.73 m², p = 0.021). Children experiencing >1 acute rejection episode had a greatly elevated risk of graft failure (p = 0.0009, OR 68.25). At latest follow-up, 64/90 (71.1%) graft recipients had a normal height, and younger graft recipients demonstrated greater catch up growth than older children. CMP-treated graft recipients showed a reduced rate of height deficit (28.9% vs. 55.1%, p = 0.0025), less obesity (12.2% vs. 23.9%, p = 0.031), and reduced rates of hypertension (35.4% vs. 68.2%, p< 0.0001).

CONCLUSIONS

Children treated with a CMP show greater height attainment, lower frequency of obesity, and reduced rates of hypertension, without an increased risk of acute rejection. Graphical abstract.

Significance of HLA-DQ in kidney transplantation: time to reevaluate human leukocyte antigen matching priorities to improve transplant outcomes? An expert review and recommendations

The weight of human leukocyte antigen (HLA) matching in kidney allocation algorithms, especially in the United States, has been devalued in a stepwise manner, supported by the introduction of modern immunosuppression. The intent was further to reduce the observed ethnic/racial disparity, as data emerged associating HLA matching with decreased access to transplantation for African American patients. In recent years, it has been increasingly recognized that a leading cause of graft loss is chronic antibody-mediated rejection, attributed to the development of de novo antibodies against mismatched donor HLA expressed on the graft. These antibodies are most frequently against donor HLA-DQ molecules. Beyond their impact on graft survival, generation of de novo donor-specific HLA antibodies also leads to increased sensitization, as measured by panel-reactive antibody metrics. Consequently, access to transplantation for patients returning to the waitlist in need of a second transplant is compromised. Herein, we address the implications of reduced HLA matching policies in kidney allocation. We highlight the observed diminished outcome data, the significant financial burden, the long-term health consequences, and, more important, the unintended consequences. We further provide recommendations to examine the impact of donor-recipient HLA class II and specifically HLA-DQα₁β₁ mismatching, focusing on collection of appropriate data, application of creative simulation approaches, and reconsideration of best practices to reduce inequalities while optimizing patient outcomes.

Long-term outcomes during 37 years of pediatric kidney transplantation: a cohort study comparing ethnic groups

BACKGROUND

This study aimed to evaluate short- and long-term outcomes of kidney transplantation over 37 years in a national referral center and compare outcomes between Israeli Jewish and Arab children.

METHODS

Data on 599 pediatric transplantations performed in 545 children during 1981-2017, including demographic parameters, kidney failure disease profile, and pre-transplant dialysis duration, were retrieved from our computerized database and patient files. Patient and graft survival were estimated using the Kaplan-Meier method.

RESULTS

Twenty-year patient survival was 91.4% for live donor (LD) and 80.2% for deceased donor (DD) kidney recipients. Respective 10-year and 20-year graft survival rates for first kidney-only transplants were 75.2% and 47.0% for LD and 60.7% and 38.4% for DD grafts. Long-term graft survival improved significantly (p < 0.001) over the study period for recipients of both LD and DD allografts and reached 7-year graft survival of 92.0% and 71.3%, respectively. The proportion of DD transplantations was higher in the Arab subpopulation: 73.8% vs. 48.4% (p < 0.001). Graft survival was not associated with age at transplantation and did not differ between the Arab (N = 202) and Jewish children (N = 343). Median (IQR) waiting time on dialysis did not differ significantly between the Arab and Jewish children: 18 (10-30) and 15 (9-30) months, respectively (p Mann-Whitney = 0.312).

CONCLUSIONS

Good and progressively improving long-term results were obtained in pediatric kidney transplantation at our national referral center, apparently due to expertise gained over time and advances in immunosuppression. Equal access to DD kidney transplant and similar graft survival were found between ethnic groups.

Pediatric kidney transplantation in China: an analysis from the IPNA Global Kidney Replacement Therapy Registry

BACKGROUND

The International Pediatric Nephrology Association (IPNA) Global Kidney Replacement Therapy (KRT) Registry was established to evaluate the incidence and outcomes of kidney replacement therapy (dialysis and transplantation) provided to children worldwide. Analysis of registry data for separate regions is feasible.

METHODS

Three centers located in Shanghai, Guangzhou, and Zhengzhou, which have the greatest number of pediatric kidney transplantation cases in China, participated in this analysis of transplant data. Data were registered by each center for patients under the age of 19 years who received a single-organ kidney transplant for the first time between 2011 and 2018.

RESULTS

In total, 415 patients (59.8% male) aged 1.4-18.7 (median 12.1) years were followed for 0.3-97.1 (median 27.7) months. The number of kidney transplants increased from a total of 129 during 2011-2014 to 286 cases during 2015-2018. 85.8% of patients received the transplanted kidney from a pediatric (age < 19 years) donor, and deceased donors accounted for 94% of all donors. 8.0% of grafts were lost. One and 5-year patient survival rates were 97.6% and 95.5%, respectively. The major cause of death was infection (7/14). Similar graft and patient survival rates were observed for organs from pediatric and adult donors in 6-11 and 12-18 year recipient age groups, whereas recipients < 6 years showed inferior patient and graft survival.

CONCLUSIONS

Pediatric kidney transplantation shows favorable short-term and medium-term outcomes in China. Our experience supports use of pediatric donors in pediatric kidney transplantation, but attention directed to the outcome of recipients aged under 6 is necessary. Graphical abstract.

The current status of kidney transplantation in Nigerian children: still awaiting light at the end of the tunnel

BACKGROUND

Kidney transplantation (KT) is the gold standard treatment for children with chronic kidney disease stage 5 (CKD5). It is easily accessible in well-resourced countries, but not in low/middle-income countries (LMICs). We present, a multicentre experience of paediatric KT of children domiciled in Nigeria. We aim to highlight the challenges and ethical dilemmas that children, their parents or guardians and health care staff face on a daily basis.

METHODS

A multicentre survey of Nigerian children who received KTs within or outside Nigeria from 1986 to 2019 was undertaken using a questionnaire emailed to all paediatric and adult consultants who are responsible for the care of children with kidney diseases in Nigeria. Demographic data, causes of CKD5, sources of funding, donor organs and graft and patient outcome were analysed. Using Kaplan-Meier survival analysis, we compared graft and patient survival.

RESULTS

Twenty-two children, aged 4-18 years, received 23 KTs, of which 12 were performed in Nigeria. The male-to-female ratio was 3.4:1. Duration of pre-transplant haemodialysis was 4-48 months (median 7 months). Sixteen KTs were self-funded. State governments funded 3 philanthropists 4 KTs. Overall differences in graft and patient survival between the two groups, log rank test P = 0.68 and 0.40, respectively were not statistically significant.

CONCLUSIONS

The transplant access rate for Nigerian children is dismal at < 0.2%. Poor funding is a major challenge. There is an urgent need for the federal government to fund health care and particularly KTs. Graphical Abstract.

Does HLA matching matter in the modern era of renal transplantation?

Children with end-stage kidney disease should be offered the best chance for future survival which ideally would be a well-matched pre-emptive kidney transplant. Paediatric and adult practice varies around the world depending on geography, transplant allocation schemes and different emphases on living (versus deceased) donor renal transplantation. Internationally, paediatric patients often have priority in allocation schemes and younger donors are preferentially allocated to paediatric recipients. HLA matching can be difficult and may result in longer waiting times. Additionally, with improved surgical techniques and modern immunosuppressive regimens, how important is the contribution of HLA matching to graft longevity? In this review, we discuss the relative importance of HLA matching compared with donor quality; and long-term patient outcomes including re-transplantation rates. We share empirical evidence that will be useful for clinicians and families to make decisions about best donor options. We discuss why living donation still provides the best allograft survival outcomes and what to do in the scenario of a highly mismatched living donor.