Growth in children on kidney replacement therapy: a review of data from patient registries

Adolescent and Young Adult Development in Transplant Recipients

Solid organ transplantation (SOT) is the gold standard of therapy for individuals with end-organ dysfunction. Improved survival outcomes after SOT can help adolescent and young adult (AYA) recipients lead long and healthy life. However, successful SOT during adolescence and young adulthood is often complicated by the innate developmental challenges of this age group. The psychosocial tasks of adolescence include identity development, autonomous decision-making, establishing social networks, educational and vocational preparation, and navigating romantic relationships. These goals may be amplified or delayed for pediatric SOT recipients. Adolescence is also marked by rapid physical changes in linear growth and the development of secondary sexual characteristics. Yet AYA may experience physical and pubertal delays related to transplantation, as well as exaggerated body image dissatisfaction due to medication side effects. Strict adherence to medication and post-transplant regimens may interfere with adolescents' desire for normalcy and fitting in with peers. Healthcare providers should be aware that AYA value education and self-empowerment in transplant care. Transplant success needs to be defined by both medical and psychosocial outcomes, particularly when it relates to the vulnerable AYA population. Fortunately, investment from the patient, family, and care team can aid in transplant recovery and success. This article will identify the developmental challenges faced by AYA undergoing solid organ transplantation as well as strategies to engage positive outcomes.

Early prediction of growth patterns after pediatric kidney transplantation based on height-related single-nucleotide polymorphisms

BACKGROUND

Growth retardation is a common complication of chronic kidney disease in children, which can be partially relieved after renal transplantation. This study aimed to develop and validate a predictive model for growth patterns of children with end-stage renal disease (ESRD) after kidney transplantation using machine learning algorithms based on genomic and clinical variables.

METHODS

A retrospective cohort of 110 children who received kidney transplants between May 2013 and September 2021 at the First Affiliated Hospital of Zhengzhou University were recruited for whole-exome sequencing (WES), and another 39 children who underwent transplant from October 2021 to March 2022 were enrolled for external validation. Based on previous studies, we comprehensively collected 729 height-related single-nucleotide polymorphisms (SNPs) in exon regions. Seven machine learning algorithms and 10-fold cross-validation analysis were employed for model construction.

RESULTS

The 110 children were divided into two groups according to change in height-for-age Z -score. After univariate analysis, age and 19 SNPs were incorporated into the model and validated. The random forest model showed the best prediction efficacy with an accuracy of 0.8125 and an area under curve (AUC) of 0.924, and also performed well in the external validation cohort (accuracy, 0.7949; AUC, 0.796).

CONCLUSIONS

A model with good performance for predicting post-transplant growth patterns in children based on SNPs and clinical variables was constructed and validated using machine learning algorithms. The model is expected to guide clinicians in the management of children after renal transplantation, including the use of growth hormone, glucocorticoid withdrawal, and nutritional supplementation, to alleviate growth retardation in children with ESRD.

HLA (emphasis on DQ) compatibility for longer allograft survival in pediatric transplantation: Modern evidence and challenges

Kidney transplantation is the treatment of choice for children with end-stage kidney failure, yet suboptimal outcomes, the need for long-term immunosuppression, and the dependency on consecutive transplants pose significant barriers to success. Providing better HLA-matched organs to pediatric patients seems to be the most logical approach to improve graft and patient outcomes and to reduce risk of anti-HLA sensitization after graft failure. We here review recent literature on HLA matching in pediatric kidney transplantation. We further review newer approaches attempting to improve matching by using molecular mismatch load analysis. Our main focus is on the role of HLA-DQ compatibility between recipient and donor. We further emphasize the need to develop creative approaches that will support HLA (and DQ) matching utilization in organ allocation schemes, at least in those geared specifically for pediatric patients.

European chronic kidney disease registries for children not on kidney replacement therapy: tools for improving health systems and patient-centred outcomes

Chronic kidney disease (CKD) in children, from birth to late adolescence, is a unique and highly challenging condition that requires epidemiological research and large-scale, prospective cohort studies. Since its first launch in 2007, the European Society for Paediatric Nephrology/European Renal Association (ESPN/ERA) Registry has collected data on patients on kidney replacement therapy (KRT). However, slowing the progression of CKD is of particular importance and thus the possibility to extend the current registry dataset to include patients in CKD stages 4-5 should be a priority. A survey was sent to the national representatives within the ESPN/ERA Registry to collect information on whether they are running CKD registries. All the representatives from the 38 European countries involved in the ESPN/ERA Registry participated in the survey. Eight existing CKD registries have been identified. General characteristics of the national registry and detailed data on anthropometry, laboratory tests and medications at baseline and at follow-up were collected. Results provided by this survey are highly promising regarding the establishment of an ESPN CKD registry linked to the ESPN/ERA KRT registry and subsequently linking it to the ERA Registry with the same patient identifier, which would allow us to monitor disease progression in childhood and beyond. It is our belief that through such linkages, gaps in patient follow-up will be eliminated and patient-centred outcomes may be improved.

Chronic kidney disease in children: an update

Chronic kidney disease (CKD) is a major healthcare issue worldwide. However, the prevalence of pediatric CKD has never been systematically assessed and consistent information is lacking in this population. The current definition of CKD is based on glomerular filtration rate (GFR) and the extent of albuminuria. Given the physiological age-related modification of GFR in the first years of life, the definition of CKD is challenging per se in the pediatric population, resulting in high risk of underdiagnosis in this population, treatment delays and untailored clinical management. The advent and spreading of massive-parallel sequencing technology has prompted a profound revision of the epidemiology and the causes of CKD in children, supporting the hypothesis that CKD is much more frequent than currently reported in children and adolescents. This acquired knowledge will eventually converge in the identification of the molecular pathways and cellular response to damage, with new specific therapeutic targets to control disease progression and clinical features of children with CKD. In this review, we will focus on recent innovations in the field of pediatric CKD and in particular those where advances in knowledge have become available in the last years, with the aim of providing a new perspective on CKD in children and adolescents.

Understanding Similarities and Differences in CKD and Dialysis Care in Children and Adults

In lower-income settings there is often a dearth of resources and nephrologists, especially pediatric nephrologists, and individual physicians often find themselves caring for patients with chronic kidney diseases and end-stage kidney failure across the age spectrum. The management of such patients in high-income settings is relatively protocolized and permits high-volume services to run efficiently. The basic principles of managing chronic kidney disease and providing dialysis are similar for adults and children, however, given the differences in body size, causes of kidney failure, nutrition, and growth between children and adults with kidney diseases, nephrologists must understand the relevance of these differences, and have an approach to providing quality and safe dialysis to each group. Prevention, early diagnosis, and early intervention with simple therapeutic and lifestyle interventions are achievable goals to manage symptoms, complications, and reduce progression, or avoid kidney failure in children and adults. These strategies currently are easier to implement in higher-resource settings with robust health systems. In many low-resource settings, kidney diseases are only first diagnosed at end stage, and resources to pay out of pocket for appropriate care are lacking. Many barriers therefore exist in these settings, where specialist nephrology personnel may be least accessible. To improve management of patients at all ages, we highlight differences and similarities, and provide practical guidance on the management of children and adults with chronic kidney disease and kidney failure. It is important that children are managed with a view to optimizing growth and well-being and maximizing future options (eg, maintaining vein health and optimizing cardiovascular risk), and that adults are managed with attention paid to quality of life and optimization of physical health.

Evaluation of height centile growth patterns compared with parental-adjusted target height following kidney transplantation

BACKGROUND

Early steroid withdrawal (ESW) improves growth following kidney transplant (KT). It is not known whether these children achieve target height within mid-parental height range post-KT.

METHODS

Retrospective analysis of growth patterns of KT recipients following ESW in our center between 2009 and 2020 had minimum follow-up period of 12 months.

RESULTS

Forty-eight (female 29.2%) KT recipients, median age 5.3 years at first KT, were included. At KT, 29 (60.4%) recipients had normal height (SDS≥-1.88) and in 23 (47.9%), the height was within their target height (parental-adjusted height SDS within ±1.55). The proportion of children achieving normal height at 1-, 2-, 3-, and 5-years post-KT (median 5.5 years) were 75%, 83.3%, 86.5%, and 88% respectively. The proportion of children achieving target height measured at the same intervals was 68.8%, 73.8%, 73%, and 80%, respectively. Children <6 years were most growth impaired at KT but were most likely to achieve target height within first-year post-KT (72%; p = .023). All 19 children with short stature at KT received dialysis. Three children received growth hormone post-KT. Children who did not achieve target height post-KT (n = 14), five had eGFR <60 mL/min/1.73 m² , and eight were on corticosteroid therapy at latest follow-up.

CONCLUSIONS

Although vast majority of children achieved normal height post-KT following ESW during the first 5 years post-KT, 20% of these children had not achieved their target height post-KT.

Nutritional and Anthropometric Indices in Children Receiving Haemodiafiltration vs Conventional Haemodialysis - The HDF, Heart and Height (3H) Study

BACKGROUND

The "HDF-Heart-Height" study showed that haemodiafiltration (HDF) is associated with improved growth compared to conventional haemodialysis (HD). We report a post-hoc analysis of this study assessing the effect of extracorporeal dialysis therapies on nutritional indices.

METHODS

107 children were included in the baseline cross-sectional analysis, of whom 79 (43 HD, 36 HDF) completed the 12-month follow-up. Height (Ht), optimal 'dry' weight (Wt), and body mass index (BMI) standard deviations scores (SDS), waist-to-hip ratio, des-acyl ghrelin (DAG), adiponectin, leptin, insulin-like growth factor-1 (IGF-1)-SDS and insulin were measured.

RESULTS

The levels of nutritional indices were comparable between HDF and HD patients at baseline and 12-month. On univariable analyses Wt-SDS positively correlated with leptin and IGF-1-SDS, and negatively with DAG, while Ht-SDS of the overall cohort positively correlated with IGF1-SDS and inversely with DAG and adiponectin. On multivariable analyses, higher 12-month Ht-SDS was inversely associated with baseline DAG (beta = -0.13 per 500 higher; 95%CI -0.22, -0.04; P = .004). Higher Wt-SDS at 12-month was positively associated with HDF modality (beta = 0.47 vs HD; 95%CI 0.12-0.83; P = .01) and inversely with baseline DAG (beta = -0.18 per 500 higher; 95%CI -0.32, -0.05; P = .006). Growth Hormone (GH) treated patients receiving HDF had higher annualized increase in Ht SDS compared to those on HD.

CONCLUSIONS

In children on HD and HDF both Wt- and Ht-SDS independently correlated with lower baseline levels of the anorexygenic hormone DAG. HDF may attenuate the resistance to GH, but further studies are required to examine the mechanisms linking HDF to improved growth.

Epidemiology of peritoneal dialysis outcomes

Peritoneal dialysis (PD) is an important home-based treatment for kidney failure and accounts for 11% of all dialysis and 9% of all kidney replacement therapy globally. Although PD is available in 81% of countries, this provision ranges from 96% in high-income countries to 32% in low-income countries. Compared with haemodialysis, PD has numerous potential advantages, including a simpler technique, greater feasibility of use in remote communities, generally lower cost, lesser need for trained staff, fewer management challenges during natural disasters, possibly better survival in the first few years, greater ability to travel, fewer dietary restrictions, better preservation of residual kidney function, greater treatment satisfaction, better quality of life, better outcomes following subsequent kidney transplantation, delayed need for vascular access (especially in small children), reduced need for erythropoiesis-stimulating agents, and lower risk of blood-borne virus infections and of SARS-CoV-2 infection. PD outcomes have been improving over time but with great variability, driven by individual and system-level inequities and by centre effects; this variation is exacerbated by a lack of standardized outcome definitions. Potential strategies for outcome improvement include enhanced standardization, monitoring and reporting of PD outcomes, and the implementation of continuous quality improvement programmes and of PD-specific interventions, such as incremental PD, the use of biocompatible PD solutions and remote PD monitoring.

The use of peritoneal dialysis (PD) can be advantageous compared with haemodialysis treatment, although several barriers limit its broad implementation. This review examines the epidemiology of peritoneal dialysis (PD) outcomes, including clinical, patient-reported and surrogate PD outcomes.

Peritoneal dialysis (PD) has distinct advantages compared with haemodialysis, including the convenience of home treatment, improved quality of life, technical simplicity, lesser need for trained staff, greater cost-effectiveness in most countries, improved equity of access to dialysis in resource-limited settings, and improved survival, particularly in the first few years of initiating therapy.

Important barriers can hamper PD utilization in low-income settings, including the high costs of PD fluids (owing to the inability to manufacture them locally and the exorbitant costs of their import), limited workforce availability and a practice culture that limits optimal PD use, often leading to suboptimal outcomes.

PD outcomes are highly variable around the world owing in part to the use of variable outcome definitions, a heterogeneous practice culture, the lack of standardized monitoring and reporting of quality indicators, and kidney failure care gaps (including health care workforce shortages, inadequate health care financing, suboptimal governance and a lack of good health care information systems).

Key outcomes include not only clinical outcomes (typically defined as medical outcomes based on clinician assessment or diagnosis) — for example, PD-related infections, technique survival, mechanical complications, hospitalizations and PD-related mortality — but also patient-reported outcomes. These outcomes are directly reported by patients and focus on how they function or feel, typically in relation to quality of life or symptoms; patient-reported outcomes are used less frequently than clinical outcomes in day-to-day routine care.