Pediatric renal transplantation: comparative study with renal transplantation in the adult population

Successful ABO and HLA incompatible kidney transplantation in children in the UK

BACKGROUND

There is increasing evidence of good short-term and medium-term outcomes of ABO incompatible (ABOi) and HLA incompatible (HLAi) kidney transplantation with pre-transplant positive crossmatches in paediatric practice. However, there remain concerns regarding the higher risks of infective complications and antibody-mediated rejections. The aim of our study is to show longer-term follow-up on all ABOi and HLAi paediatric kidney transplant recipients (pKTR) in the UK.

METHODS

Questionnaires specifying kidney transplant type, desensitisation requirement and kidney allograft function were sent to 13 paediatric nephrology centres that performed kidney transplantation in children and young people under 18 years of age who received an ABOi and/or HLAi transplant between 1 January 2006 and 31 December 2016. Patient and kidney allograft survival were compared between ABOi, HLAi and ABO/HLA compatible (ABOc/HLAc) groups.

RESULTS

Among 711 living donor kidney transplants performed in the UK, 23 were ABOi and 6 were HLAi. Patient survival was 87%, 100% and 96% in ABOi, HLAi and ABOc/HLAc groups, respectively, at median follow-up of 6.8 (3.6-14.0) years post-transplant. Death-censored kidney allograft survival was 100% in all 3 groups at last follow-up. There were no cases of primary non-function in ABOi or HLAi groups, but 2% in the ABOc/HLAc group. There was one reported case of Epstein-Barr viral-induced post-transplant lymphoproliferative disorder.

CONCLUSION

Longer term follow-up has shown that ABOi and HLAi kidney transplantation are feasible for pKTR where no compatible donors are available, and that minimising desensitisation should be achieved where possible. A higher resolution version of the Graphical abstract is available as Supplementary information.

Pearls and Pitfalls in Pediatric Kidney Transplantation After 5 Decades

Worldwide, over 1,300 pediatric kidney transplantations are performed every year. Since the first transplantation in 1959, healthcare has evolved dramatically. Pre-emptive transplantations with grafts from living donors have become more common. Despite a subsequent improvement in graft survival, there are still challenges to face. This study attempts to summarize how our understanding of pediatric kidney transplantation has developed and improved since its beginnings, whilst also highlighting those areas where future research should concentrate in order to help resolve as yet unanswered questions. Existing literature was compared to our own data of 411 single-center pediatric kidney transplantations between 1968 and 2020, in order to find discrepancies and allow identification of future challenges. Important issues for future care are innovations in immunosuppressive medication, improving medication adherence, careful donor selection with regard to characteristics of both donor and recipient, improvement of surgical techniques and increased attention for lower urinary tract dysfunction and voiding behavior in all patients.

Pediatric Renal Transplantation: Evaluation of Long-Term Outcomes and Comparison to Adult Population

BACKGROUND

In Europe, pediatric transplantation accounts for only about 4% of all kidney transplantations performed. The aim of our work is to evaluate the evolution of pediatric renal transplantation in our department over time, but also to compare this special population with the adult one.

METHODS

We evaluated all pediatric renal transplantations performed in our department between January 1981 and December 2016. We performed the analysis of clinical, analytical, and surgical factors to look for predictive factors of graft loss or decrease of survival. In addition, we performed a comparative study of pediatric and adult populations and an evaluation of the evolution of pediatric renal transplantation in our department over time.

RESULTS

We evaluated 101 renal transplantations performed in patients younger than 18 years. Pediatric transplantations corresponded to 3.4% of all renal transplantations performed in our department. The rate of living donors was 12%. Donors of grafts for the pediatric population were significantly younger than in the adult population. The increase in donor age was associated with lower renal graft survival rates. Acute rejections were more frequent in the pediatric population. Eleven pediatric recipients (10.9%) died in the follow-up period. Renal graft survival in the pediatric population was 94.8%, 77.4%, and 66.5% at 1, 5, and 10 years, respectively. There was no significant difference in graft survival in the pediatric and adult population. The pediatric overall survival rate at 1, 5 and 10 years was 97.9%, 96.8%, and 91.9%, respectively.

CONCLUSION

Pediatric renal transplantation presents results identical to those identified in adults.

Pediatric kidney transplantation is different from adult kidney transplantation

Kidney transplantation (KT) is the gold standard for renal replacement therapy in pediatric patients with end-stage renal disease. Recently, it has been observed that the outcome of pediatric KT is nearly identical to that in adults owing to the development and application of a variety of immunosuppressants and newer surgical techniques. However, owing to several differences in characteristics between children and adults, pediatric KT requires that additional information be learned and is associated with added concerns. These differences include post-KT complications, donor-recipient size mismatch, problems related to growth, and nonadherence to therapy, among others. This review was aimed at elucidating the clinical characteristics of pediatric KT that differ from those observed in adults.

Current status of pediatric renal transplant pathology

Histopathology is still an indispensable tool for the diagnosis of kidney transplant dysfunction in adult and pediatric patients. This review presents consolidated knowledge, recent developments and future prospects on the biopsy procedure, the diagnostic work-up, classification schemes, the histopathology of rejection, including antibody-mediated forms, ABO-incompatible transplants, protocol biopsies, recurrent and de novo disease, post-transplant lymphoproliferative disorder, infectious complications and drug-induced toxicity. It is acknowledged that frequently the correct diagnosis can only be reached in consensus with clinical, serological, immunogenetical, bacteriological and virological findings. This review shall enhance the understanding of the pediatric nephrologist for the thought processes of nephropathologists with the aim to facilitate teamwork between these specialist groups for the benefit of the patient.

Calcineurin inhibitor sparing strategies in renal transplantation, part one: Late sparing strategies

Kidney transplantation improves quality of life and reduces the risk of mortality. A majority of the success of kidney transplantation is attributable to the calcineurin inhibitors (CNIs), cyclosporine and tacrolimus, and their ability to reduce acute rejection rates. However, long-term graft survival rates have not improved over time, and although controversial, evidence does suggest a role of chronic CNI toxicity in this failure to improve outcomes. Consequently, there is interest in reducing or removing CNIs from immunosuppressive regimens in an attempt to improve outcomes. Several strategies exist to spare calcineurin inhibitors, including use of agents such as mycophenolate mofetil (MMF), mycophenolate sodium (MPS), sirolimus, everolimus or belatacept to facilitate late calcineurin inhibitor withdrawal, beyond 6 mo post-transplant; or using these agents to plan early withdrawal within 6 mo; or to avoid the CNIs all together using CNI-free regimens. Although numerous reviews have been written on this topic, practice varies significantly between centers. This review organizes the data based on patient characteristics (i.e., the baseline immunosuppressive regimen) as a means to aid the practicing clinician in caring for their patients, by matching up their situation with the relevant literature. The current review, the first in a series of two, examines the potential of immunosuppressive agents to facilitate late CNI withdrawal beyond 6 mo post-transplant, and has demonstrated that the strongest evidence resides with MMF/MPS. MMF or MPS can be successfully introduced/maintained to facilitate late CNI withdrawal and improve renal function in the setting of graft deterioration, albeit with an increased risk of acute rejection and infection. Additional benefits may include improved blood pressure, lipid profile and serum glucose. Sirolimus has less data directly comparing CNI withdrawal to an active CNI-containing regimen, but modest improvement in short-term renal function is possible, with an increased risk of proteinuria, especially in the setting of baseline renal dysfunction and/or proteinuria. Renal outcomes may be improved when sirolimus is used in combination with MMF. Although data with everolimus is less robust, results appear similar to those observed with sirolimus.

Pediatric renal transplantation: results and prognostic factors

BACKGROUND/OBJECTIVE

As renal transplantation may increase survival rates and improve quality of life for children with end-stage renal disease, we investigated the long-term outcomes and prognostic factors of pediatric renal transplantation.

METHODS

A retrospective study was conducted to review 25 pediatric renal transplantations, either from live or deceased donors, in our hospital from 1995 to 2008. The cumulative graft survival rate was calculated using the Kaplan-Meier method. Log rank tests were employed to identify categorical prognostic factors for graft survival of the pediatric renal transplantations, and Cox regression analysis for numeric factors.

RESULTS

The mean age of our study subjects was 11.63±3.76 years, and the mean follow-up period was 49.24±33.72 months. The 12-month and 36-month graft survival rates were 92% and 82.14%, respectively. The rejection-free survival rates were 88% and 72.88% in the first and third years, respectively. All of the patients were alive during the follow-up period. Acute rejection (p=0.0175) and male sex (p=0.0384) were found to be significant factors for graft survival.

CONCLUSION

For pediatric patients, we found that renal transplantation is now a safe and effective surgical procedure for children with end-stage renal disease. Acute rejection and male gender were identified as prognostic factors for poor graft survival.

Development and validation of a new statistical model for prognosis of long-term graft function after pediatric kidney transplantation

BACKGROUND

No adequate statistical model has been established to estimate future glomerular filtration rate (GFR) in children after kidney transplantation (KTX). Equations based on simple linear regression analysis as used in adults are not established in children.

METHODS

An optimal prognostic model of GFR was generated for 63 children at 3-7 years after KTX. The main regression model for prediction of the log-transformed GFR (logGFR) included the mean monthly change of GFR in the period 3-24 months after KTX (∆GFR), the baseline GFR at 3 months (bGFR), and an intercept. Additionally, we investigated if the inclusion of cofactors leads to more precise predictions. The model was validated by leave-one-out cross-validation for years 3-7 after KTX. Prognostic quality was determined with the mean squared error (MSE) and mean absolute error (MAE). Results were compared with the simple linear regression model used in adults.

RESULTS

The following statistical model was calculated for every prognosis year (i = 3, …, 7):[Formula: see text] [Formula: see text] Comparison of the new statistical model and the simple linear model for adults led to relevantly lower MSEs and MAEs for the new model (year 7: New model: MSE 0.1, MAE 0.3/adult model: MSE 1069, MAE 18). The benefit of inclusion of cofactors was not relevant.

CONCLUSIONS

This statistical model is able to predict long-term graft function in children with very high precision.

Long-term survival of living donor renal transplants: A single center study

Kidney transplantation is the treatment of choice for end-stage renal disease. The aim of this study was to determine the ten-year graft survival rate of renal transplantation in patients who have been transplanted from live donors. This is a historical cohort study designed to determine the organ survival rate after kidney transplantation from live donor during a 10-year period (from March 1999 to March 2009) on 843 patients receiving kidney transplant in the transplantation center of Namazi hospital in Shiraz, Iran. Kaplan-Meier method was used to determine the survival rate, log-rank test was used to compare survival curves, and Cox proportional hazard model was used to multivariate analysis. Mean follow-up was 53.07 ± 34.61 months. Allograft survival rates at 1, 3, 5, 7, and 10 years were 98.3, 96.4, 92.5, 90.8, and 89.2%, respectively. Using Cox proportional hazard model, the age and gender of the donors along with the creatinine level of the patients at discharge were shown to have a significant influence on survival. The 10-year graft survival rate of renal transplantation from living donor in this center is 89.2%, and graft survival rate in our cohort is satisfactory and comparable with reports from large centers in the world.

Effect of donor and recipient variables on the long-term live-donor renal allograft survival in children

Objective

We aimed to analyse donor and recipient predictors of graft survival in children who received live-donor renal grafts.

Patients and methods

The study comprised 273 children who received live-donor renal transplants at our center between March 1976 and October 2010. The follow-up ranged from 6 months to 25 years. Donor variables included donor age, gender, donor/recipient body weight ratio (DR BWR), ABO blood groups, human leukocyte antigen, and DR mismatching. Donor-specific problems, e.g., ischemia time during surgery and number of renal arteries, were included. Recipient variables included recipient age, sex, original kidney disease, ischemia time, acute tubular necrosis (ATN) after transplantation, immunosuppression, number of acute rejection episodes, re-transplantation, and development of hypertension.

Results

Independent variables with a sustained effect on the 5- and 10-year graft survival on multivariate analysis were: ATN after transplant, number of acute rejections, hypertension, and DR BWR. At the last follow-up, 185 patients (67.8%) had a functioning graft, while 82 (30.0%) had graft failure. Only six patients (0.02%) were lost to follow-up.

Conclusion

Donor and recipient variables that affect short- and long-term graft survival in children with a live-donor renal allograft are DR BWR, number of acute rejections, ATN and hypertension after transplant. Considering these variables provides a better outcome.

Second cadaveric kidney transplantations in the pediatric population

OBJECTIVE

To evaluate the functional outcomes and complications among a series of second in comparison to first kidney transplantations in pediatric patients.

MATERIALS AND METHODS

We reviewed 163 consecutive kidney transplants in pediatric recipients performed from 1978 to present: 120 cases (69.3%) were first transplants (group A) and 43 (24.8%), second transplant (group B). We analyzed the incidences of delayed graft function (DGF), medical and surgical complications, as well as medium- and long-term graft survivals.

RESULTS

We observed DGF among 51 group A patients (43%) versus 32.5% of group B. Ten patients suffered vascular complications in group A (8.3%) versus one in group B (2.3%) (P < .05). The 15-year graft survivals were 54.2% for group A and 45% for group B. The 15-year patient survivals were 84.9% in group A versus 93.6% in group B.

CONCLUSIONS

Second kidney transplantations for children are a satisfactory option that achieves good functional results as well as acceptable graft and patient survivals.

Sex, race, and socioeconomic disparities in kidney disease in children

Racial and gender differences in the prevalence and treatment of chronic kidney disease in US children have been reported. Girls have lower rates of kidney transplantation than boys. Incidence of end-stage renal disease is twice as high among black patients compared with whites. African Americans are less likely than white patients to achieve hemoglobin targets on dialysis, are more likely to be treated with hemodialysis, and to wait longer for a transplant. Reasons for these disparities in disease burden and treatment choices are not known, but possible causes include genetic factors and socioeconomic and sociocultural influences on accessing medical care.

The relationship of donor source and age on short- and long-term allograft survival in pediatric renal transplantation

Limited pediatric data on allograft survival from advanced aged kidney donors exist. To determine the influence of donor source and age on allograft survival in pediatric renal transplant recipients, we analyzed the OPTN database. Allograft survival for 7291 pediatric renal transplants was evaluated. Up to five yr post-transplantation, graft survival was higher for LD vs. DD recipients. At seven yr, allograft survival was 71% in 18-54 yr-old LD recipients, 59.1% in >or=55 yr-old LD, and 45.1% in >or=50 yr-old DD recipients. An approximate 35% improvement in allograft survival in 18-54 yr-old LD recipients was observed. Multivariate results showed that recipients of LD 35-49 (aRR 0.66, 95% CI 0.55-0.80) and LD 50-54 (aRR 0.65, 95% CI 0.45-0.94) have a graft survival advantage over the ideal DD. In LD >or=55 yr, no improvement in graft survival was observed when compared with the 18-34 yr-old DD. In summary, we observed in a pediatric population, <55 yr-old LD kidneys afford improved long-term allograft survival when compared with DD kidney recipients. Increasing awareness of the long-term graft survival advantage for children receiving an LD kidney, even from older donors, should be a priority.

The long-term outcomes of pediatric kidney transplantation: a single-centre experience in China

To explore the long-term outcomes of paediatric kidney transplantation and the effects of renal allograft on growth, education, employment, marriage and procreation. Twenty-seven children with ESRD received the renal allograft from 1985 to 2001. The patient and kidney survival rate, renal function, growth and employment, etc., were reviewed retrospectively. The average follow-up period was 10.3 +/- 4.4 yr. The one-, three-, five- and 10-yr graft survival rates were 96.3%, 88.9%, 81.5% and 66.7%, respectively, and the corresponding patient survival rates were 100%, 92.6%, 85.2% and 68.8%. The body weight gain was 4-10 kg in one-yr post-operative and the height increased 0-2 cm for girls and 2-5 cm for boys. A total of 44.4% of the recipients accomplished their education above junior high school. The employment rate was 46.2% in males, and 57.2% in females. Twelve patients were married. Non-adherence occurred in 30% of the recipients. Forty percent of the surviving recipients developed complications. Seven patients died. More attention should be paid to non-adherence of medications and more supports from the society are required to improve the life quality of paediatric recipients, especially in employment and education.

Factors affecting graft function in pediatric and adult recipients of adult live donor kidney transplants

The aims of this investigation were to compare changes of function of adult living kidney grafts transplanted into adult and child recipients and to analyze factors associated with graft function during the first post-transplant year. The study involved 53 adult and 23 pediatric recipients with immediate graft function and without complications that could influence graft function. In comparison to children, adult recipients and their donors were older, and having been longer on hemodialysis they had received more transfusions. Although similar baseline graft function--GFR(0) was transplanted in both groups, absolute and relative GFR in adults rose and maintained stable, while in children absolute GFR decreased and remained similar to the GFR(0) until the end of the study. Significant predictors of kidney function in both adult and child recipients were donor age, ratio between GFR(0) and recipient BSA, induction immunosuppression, and systolic hypertension. In conclusion, the function of adult live kidney grafts changed differently in children and adults because of different functional requirements of recipients but donor age, induction immunosuppression and hypertension are significant predictor of graft function in both adults and children.

Outcome of Living Kidney Transplant: Pediatric in Comparison to Adults

BACKGROUND

Renal transplantation is the most optimal way to manage children with end-stage renal disease. Despite its benefits, pediatric renal transplantation is a challenge for several transplantation centers in terms of achieving a satisfactory outcome. We sought to compare the long-term outcome of pediatric versus adult recipients who underwent renal transplantation.

METHOD

We examined, 2631 recipients of a first kidney from a living donor between 1982 and 2002. The two groups were matched for immunosuppressive therapy and number of HLA mismatches. The patients were divided into a pediatric (n=301; age <or= 18 years) and an adult group (n=2330; age > 18 years) to compare 5-year patient and graft survivals.

RESULTS

The mean ages of the pediatric and adult groups were 40 +/- 13 and 14 +/- 13 years, respectively. The 5-year graft survival was lower among the pediatric versus the adult group (56% vs 68%; P=.015) with no difference in patient survival (88% vs 86%; P>.05).

CONCLUSION

The poorer graft survival in pediatric transplantation may be due to the nature of pediatric transplantation, in terms of inconsistent adherence to medication regimens, worse side effects of medications, higher rate of graft rejection due to recurrent disease, and more intense immunoreactivity of children.