Use of rhGH in children with chronic kidney disease: lessons from NAPRTCS

Optimizing growth in pediatric renal transplant recipients: An update

Growth retardation is a significant complication observed in pediatric renal transplant recipients, originating from a multifactorial etiology. Factors contributing to growth impairment encompass pre-transplant conditions such as primary kidney disease, malnutrition, quality of care, growth deficits at the time of transplantation, dialysis adequacy, and the use of recombinant human growth hormone. Additionally, elements related to the renal transplant itself, such as living donors, corticosteroid usage, and graft functioning, further compound the challenge. Although renal transplantation is the preferred renal replacement therapy, its impact on achieving final height and normal growth in children remains uncertain. The consequences of growth delay extend beyond the physiological realm, negatively influencing the quality of life and social conditions of pediatric renal transplant recipients, and ultimately affecting their educational and employment outcomes. Despite advancements in graft survival rates, growth retardation remains a formidable clinical concern among children undergoing renal transplantation. Major risk factors for delayed final adult height include young age at transplantation, pre-existing short stature, and the use of specific immunosuppressive drugs, particularly steroids. Effective management of growth retardation necessitates early intervention, commencing even before transplantation. Strategies involving the administration of recombinant growth hormone both pre- and post-transplant, along with protocols aimed at minimizing steroid usage, are important for achieving catch-up growth. This review provides a comprehensive outline of the multifaceted nature of growth retardation in pediatric renal transplant recipients, emphasizing the importance of early and targeted interventions to mitigate its impact on the long-term well-being of these children from birth to adolescence.

Chronic Kidney Disease Interplay with Comorbidities and Carbohydrate Metabolism: A Review

Chronic kidney disease (CKD) poses a global health challenge, engendering various physiological and metabolic shifts that significantly impact health and escalate the susceptibility to severe illnesses. This comprehensive review delves into the intricate complexities of CKD, scrutinizing its influence on cellular growth homeostasis, hormonal equilibrium, wasting, malnutrition, and its interconnectedness with inflammation, oxidative stress, and cardiovascular diseases. Exploring the genetic, birth-related, and comorbidity factors associated with CKD, alongside considerations of metabolic disturbances, anemia, and malnutrition, the review elucidates how CKD orchestrates cellular growth control. A pivotal focus lies on the nexus between CKD and insulin resistance, where debates persist regarding its chronological relationship with impaired kidney function. The prevalence of insulin abnormalities in CKD is emphasized, contributing to glucose intolerance and raising questions about its role as a precursor or consequence. Moreover, the review sheds light on disruptions in the growth hormone and insulin-like growth factor axis in CKD, underscoring the heightened vulnerability to illness and mortality in cases of severe growth retardation. Wasting, a prevalent concern affecting up to 75% of end-stage renal disease (ESRD) patients, is analyzed, elucidating the manifestations of cachexia and its impact on appetite, energy expenditure, and protein reserves. Taste disturbances in CKD, affecting sour, umami, and salty tastes, are explored for their implications on food palatability and nutritional status. Independent of age and gender, these taste alterations have the potential to sway dietary choices, further complicating the management of CKD. The intricate interplay between CKD, inflammation, oxidative stress, and cardiovascular diseases is unraveled, emphasizing the profound repercussions on overall health. Additionally, the review extends its analysis to CKD's broader impact on cognitive function, emotional well-being, taste perception, and endothelial dysfunction. Concluding with an emphasis on dietary interventions as crucial components in CKD management, this comprehensive review navigates the multifaceted dimensions of CKD, providing a nuanced understanding essential for developing targeted therapeutic strategies.

Unveiling the Clinical Benefits of High-Volume Hemodiafiltration: Optimizing the Removal of Medium-Weight Uremic Toxins and Beyond

Dialysis treatment has improved the survival of patients with kidney failure. However, the hospitalization and mortality rates remain alarmingly high, primarily due to incomplete uremic toxin elimination. High-volume hemodiafiltration (HDF) has emerged as a promising approach that significantly improves patient outcomes by effectively eliminating medium and large uremic toxins, which explains its increasing adoption, particularly in Europe and Japan. Interest in this therapy has grown following the findings of the recently published CONVINCE study, as well as the need to understand the mechanisms behind the benefits. This comprehensive review aims to enhance the scientific understanding by explaining the underlying physiological mechanisms that contribute to the positive effects of HDF in terms of short-term benefits, like hemodynamic tolerance and cardiovascular disease. Additionally, it explores the rationale behind the medium-term clinical benefits, including phosphorus removal, the modulation of inflammation and oxidative stress, anemia management, immune response modulation, nutritional effects, the mitigation of bone disorders, neuropathy relief, and amyloidosis reduction. This review also analyzes the impact of HDF on patient-reported outcomes and mortality. Considering the importance of applying personalized uremic toxin removal strategies tailored to the unique needs of each patient, high-volume HDF appears to be the most effective treatment to date for patients with renal failure. This justifies the need to prioritize its application in clinical practice, initially focusing on the groups with the greatest potential benefits and subsequently extending its use to a larger number of patients.

Effectiveness and Overall Safety of NutropinAq® for Growth Hormone Deficiency and Other Paediatric Growth Hormone Disorders: Completion of the International Cooperative Growth Study, NutropinAq® European Registry (iNCGS)

Objective

The International Cooperative Growth Study, NutropinAq® European Registry (iNCGS) (NCT00455728) monitored long-term safety and effectiveness of recombinant human growth hormone (rhGH; NutropinAq® [somatropin]) in paediatric growth disorders.

Methods

Open-label, non-interventional, post-marketing surveillance study recruiting children with growth disorders. Endpoints included gain in height standard deviation score (SDS), adult height, and occurrence of adverse events (AEs).

Results

2792 patients were enrolled. 2082 patients (74.6%) had growth hormone deficiency (GHD), which was isolated idiopathic in 1825 patients (87.7%). Non-GHD diagnoses included Turner syndrome (TS) (n=199), chronic renal insufficiency (CRI) (n=10), other non-GHD (n=498), and missing data for three participants. Improvements from baseline height SDS occurred at all time points to Month 132, and in all subgroups by disease aetiology. At Month 12, mean (95% CI) change in height SDS by aetiology was: idiopathic GHD 0.63 (0.61;0.66), organic GHD 0.71 (0.62;0.80), TS 0.59 (0.53; 0.65), CRI 0.54 (-0.49;1.56), and other non-GHD 0.64 (0.59;0.69). Mean height ( ± SD) at the last visit among the 235 patients with adult or near-adult height recorded was 154.0 cm ( ± 8.0) for girls and 166.7 cm ( ± 8.0) for boys. The most frequent biological and clinical non-serious drug-related AEs were increased insulin-like growth factor concentrations (314 events) and injection site haematoma (99 events). Serious AEs related to rhGH according to investigators were reported (n=30); the most frequent were scoliosis (4 events), epiphysiolysis (3 events), and strabismus (2 events).

Conclusions

There was an improvement in mean height SDS in all aetiology subgroups after rhGH treatment. No new safety concerns were identified.

The Role of Growth Hormone in Chronic Kidney Disease

Growth hormone (GH) has become a critical therapy for treating growth delay and failure in pediatric chronic kidney disease. Recombinant human GH treatment is safe and significantly improves height and height velocity in these growing patients and improved growth outcomes are associated with decreased morbidity and mortality as well as improved quality of life. However, the utility of recombinant human GH in adults with chronic kidney disease and end-stage renal disease for optimization of body habitus and reducing frailty remains uncertain. Semin Nephrol 41:x-xx © 2021 Elsevier Inc. All rights reserved.

Summary of Expert Opinion on the Management of Children With Chronic Kidney Disease and Growth Failure With Human Growth Hormone

Background: The management of children and adolescents with chronic kidney disease (CKD) and growth failure candidate for recombinant human growth hormone therapy (rhGH) is based on an appraisal of the literature established on a 2006 consensus statement and 2019 Clinical practice recommendations. The performance of these guidelines has never been tested. Aims: The objective of this study was to establish the level of adherence to international guidelines based on the 2006 consensus and the 2019 criteria that lead to the initiation of growth hormone treatment by both pediatric endocrinologists and pediatric nephrologists. Methods: A multidisciplinary team of pediatric endocrinologists and pediatric nephrologists, members of the Italian Society of Pediatric Endocrinology or of the Italian Society of Pediatric Nephrology, discussed and reviewed the main issues related to the management of pediatric patients with CKD who need treatment with rhGH. Experts developed 11 questions focusing on risk assessment and decision makings in October 2019 and a survey was sent to forty pediatric endocrinologists (n = 20) and nephrologists (n = 20) covering the whole national territory. The results were then analyzed and discussed in light of current clinical practice guidelines and recent recommendations. Results: Responses were received from 32 of the 40 invited specialists, 17 of whom were pediatric endocrinologists (42.5%) and 15 pediatric nephrologists (37.5%). Although all the centers that participated in the survey agreed to follow the clinical and biochemical diagnostic work-up and the criteria for the treatment of patients with CKD, among the Italian centers there was a wide variety of decision-making processes. Conclusions: Despite current guidelines for the management of children with CKD and growth failure, its use varies widely between centers and rhGH is prescribed in a relatively small number of patients and rarely after kidney transplantation. Several raised issues are not taken into account by international guidelines and a multidisciplinary approach with mutual collaboration between specialists will improve patient care based on their unmet needs.

Growth characterization in a cohort of renal allograft recipients

INTRODUCTION

Growth retardation is a common problem in children with CKD. This study aims to describe growth, prevalence of short stature before RTx, catch-up growth after RTx, and associated factors.

METHODS

We retrospectively reviewed 74 renal allograft recipients who underwent RTx at Fundación Cardioinfantil, Colombia, between January 2008 and September 2016 with follow-up for 2 years afterwards. Pre-RTx Height_SDS and demographic characteristics were compared between children with normal and short stature. Post-RTx Height_SDS at 1 and 2 years post-RTx and FAH, when available, were retrieved. Children were classified into catch-up growth and no catch-up growth groups depending on whether or not Height_SDS increased ≥0.5 per year within the first 2 years post-RTx. Possible associated factors were compared.

RESULTS

Seventy-four patients were included. Mean age at RTx was 11 ± 4.0 years, and 43.2% (32/74) were females. Mean Height_SDS for the entire study population at pre-RTx was -2.8 ± 1.5. Before RTx, 68.9% (51/74) had short stature, and 44.6% (33/74) had severe short stature. 37.2% presented catch-up growth post-RTx. Time on dialysis was associated with short pre-RTx stature (OR 1.66; 95% CI [1.15-2.39]; P = .006) and catch-up growth (OR 2.15; 95% CI [1.15-3.99]; P = .016). 44.59% (33/74) reached FAH, and 48.4% (16/33) presented short FAH.

CONCLUSIONS

Growth continues to be suboptimal after RTx. Given that pre-RTx height is a significantly associated factor, it is important to plan early interventions in terms of growth improvement in these children.

Mental health and psychosocial adjustment in pediatric chronic kidney disease derived from the KNOW-Ped CKD study

BACKGROUND

Psychosocial development of pediatric chronic kidney disease (CKD) patients is substantially affected due to growth retardation, frequent school absences, and difficulties engaging in normal peer relationship activities. While many studies focus on specific issues such as depression, anxiety, or neurocognitive function, few evaluate prevalence of various types of mental health and psychosocial adjustment problems among children with CKD. This study aimed to investigate these within the KoreaN cohort study for Outcomes in patients With Pediatric Chronic Kidney Disease (KNOW-Ped CKD).

METHODS

One hundred sixty-six subjects who completed the Korean-Child Behavioral Checklist (K-CBCL) were included. The clinical group comprised subjects with scores indicating psychosocial adjustment or mental health problems using the T scores for the 14 subscales of the K-CBCL. We analyzed associations between mental health or adjustment problems in pediatric CKD and each variable.

RESULTS

Mean age was 11.1 (± 3.9) years, number of males was 117 (70.5%), and 20.5% and 22.3% of children had significant mental health problems and psychosocial adjustment problems, respectively. Overall, 33.1% were assigned to the clinical group, and exhibited short stature and higher rates of preterm birth history compared to the non-clinical group. Subjects with adjustment problems had higher comorbidities such as CNS disease, developmental delay, cardiovascular disease, and multi-organ involvement. Logistic regression analysis revealed preterm birth and developmental delay correlated highly with clinical group.

CONCLUSIONS

A significant proportion of children and adolescents with CKD experience mental health and adjustment problems. In particular, patients with developmental delay or preterm birth history require screening and targeted follow-up.

Health-related quality of life of children with pre-dialysis chronic kidney disease

BACKGROUND

The goal of this study was to evaluate the quality of life (QOL) of Asian children with pre-dialysis chronic kidney disease (CKD) and to reveal the factors influencing the QOL of children with CKD.

METHODS

We performed a cross-sectional study of the PedsQL 4.0 Generic Core Scale Module in the KNOW-PedCKD (KoreaN cohort study for Outcome in patients with Pediatric Chronic Kidney Disease) cohort, and compared the child self-reported and parent proxy-reported QOL of the pediatric cohort. From 2011 through 2016, a total of 376 children with CKD were enrolled after informed consent was obtained from parents or caregivers in seven pediatric nephrology centers.

RESULTS

In parent proxy-reports, male patients had a better QOL than female patients in the Physical Functioning category. In child self-reports, male patients had better QOL than female patients in the Physical, Emotional, and School Functioning categories. According to CKD stage, there were significant differences in the QOL score in all categories of parent proxy-reports, and patients with higher CKD stage (lower glomerular filtration rate) had a worse QOL. Growth parameters showed a significantly positive correlation with the QOL score in all categories.

CONCLUSIONS

The QOL of children with predialysis CKD is affected by various factors, including sex, glomerular filtration rate (GFR), socio-economic status, existence of co-morbidities, anemia, growth retardation, and behavioral disorders. To improve their QOL, it is important to objectively understand the respective effects of these factors and attempt early intervention.

Approach to growth hormone therapy in children with chronic kidney disease varies across North America: the Midwest Pediatric Nephrology Consortium report

Background

Growth impairment remains common in children with chronic kidney disease (CKD). Available literature indicates low level of recombinant human growth hormone (rhGH) utilization in short children with CKD. Despite efforts at consensus guidelines, lack of high-level evidence continues to complicate rhGH therapy decision-making and the level of practice variability in rhGH treatment by pediatric nephrologists is unknown.

Methods

Cross-sectional online survey electronically distributed to pediatric nephrologists through the Midwest Pediatric Nephrology Consortium and American Society of Pediatric Nephrology.

Results

Seventy three pediatric nephrologists completed the survey. While the majority (52.1%) rarely involve endocrinology in rhGH management, 26.8% reported that endocrinology managed most aspects of rhGH treatment in their centers. The majority of centers (68.5%) have a dedicated renal dietitian, but 20.6% reported the nephrologist as the primary source of nutritional support for children with CKD. Children with growth failure did not receive rhGH most commonly because of family refusal. Differences in initial work-up for rhGH therapy include variable use of bone age (95%), thyroid function (58%), insulin-like growth factor-1 (40%), hip/knee X-ray (36%), and ophthalmologic evaluation (7%). Most pediatric nephrologists (95%) believe that rhGH treatment improves quality of life, but only 24% believe that it improves physical function; 44% indicated that rhGH improves lean body mass.

Conclusions

There is substantial variation in pediatric nephrology practice in addressing short stature and rhGH utilization in children with CKD. Hence, there may be opportunities to standardize care to study and improve growth outcomes in short children with CKD.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-017-0599-1) contains supplementary material, which is available to authorized users.

PROGRESSION OF CHRONIC KIDNEY DISEASE AFTER ACUTE KIDNEY INJURY

The incidence of chronic kidney disease (CKD) in children and adults is increasing. Cardiologists have become indispensable members of the care provider team for children with CKD. This is partly due to the high incidence of CKD in children and adults with congenital heart disease, with current estimates of 30-50%. In addition, the high incidence of acute kidney injury (AKI) due to cardiac dysfunction or following pediatric cardiac surgery that may progress to CKD is also well documented. It is now apparent that AKI and CKD are uniquely intertwined as interconnected syndromes. Furthermore, the well-known long-term cardiovascular morbidity and mortality associated with CKD require the joint attention of both nephrologists and cardiologists. Children with both congenital heart disease and CKD are increasingly surviving to adulthood, with synergistically negative medical, financial, and quality of life impact. An improved understanding of the epidemiology, mechanisms, early diagnosis, and preventive measures is of importance to cardiologists, nephrologists, scientists, economists, and policy makers alike. Herein, we report the current definitions, epidemiology, and complications of CKD in children, with an emphasis on children with congenital heart disease. We then focus on the clinical and experimental evidence for the progression of CKD after episodes of AKI commonly encountered in children with heart disease, and explore the role of novel biomarkers for the prediction of CKD progression.

KNOW-Ped CKD (KoreaN cohort study for outcomes in patients with pediatric CKD): Design and methods

Background

The global prevalence of chronic kidney disease (CKD) is increasing. In children, CKD exhibits unique etiologies and can have serious impacts on children’s growth and development. Therefore, an aggressive approach to preventing the progression of CKD and its complications is imperative. To improve the understanding and management of Asian pediatric patients with CKD, we designed and launched KNOW-Ped CKD (KoreaN cohort study for Outcome in patients With Pediatric Chronic Kidney Disease), a nationwide, prospective, and observational cohort study of pediatric CKD with funding from the Korean government.

Methods/design

From seven major centers, 450 patients <20 years of age with CKD stages I to V are recruited for the comprehensive assessment of clinical findings, structured follow-up, and bio-specimen collection. The primary endpoints include CKD progression, defined as a decline of estimated glomerular filtration rate by 50 %, and a requirement for renal replacement therapy or death. The secondary outcomes include the development of left ventricular hypertrophy or hypertension, impairment of growth, neuropsychological status, behavioral status, kidney growth, and quality of life.

Discussion

With this study, we expect to obtain more information on pediatric CKD, which can be translated to better management for the patients.

Trial registration

NCT02165878 (ClinicalTrials.gov), submitted on June 11, 2014.

Growth in Children with Autosomal Recessive Polycystic Kidney Disease in the CKiD Cohort Study

BACKGROUND

Previous studies have suggested that some children with autosomal recessive polycystic kidney disease (ARPKD) have growth impairment out of proportion to their degree of chronic kidney disease (CKD). The objective of this study was to systematically compare growth parameters in children with ARPKD to those with other congenital causes of CKD in the chronic kidney disease in Children (CKiD) prospective cohort study.

METHODS

Height SD scores (z-scores), proportion of children with severe short stature (z-score < -1.88), rates of growth hormone use, and annual change in height z-score were analyzed in children with ARPKD (n = 22) compared with two matched control groups: children with aplastic/hypoplastic/dysplastic kidneys (n = 44) and obstructive uropathy (OU) (n = 44). Differences in baseline characteristics were tested by Wilcoxon rank-sum test or Fisher's exact test. Matched differences in annual change in height z-score were tested by Wilcoxon signed-rank test.

RESULTS

Median height z-score in children with ARPKD was -1.1 [interquartile range -1.5, -0.2]; 14% of the ARPKD group had height z-score < -1.88, and 18% were using growth hormone. There were no significant differences in median height z-score, proportion with height z-score < -1.88, growth hormone use, or annual change in height z-score between the ARPKD and control groups.

CONCLUSION

Children with ARPKD and mild-to-moderate CKD in the CKiD cohort have a high prevalence of growth abnormalities, but these are similar to children with other congenital causes of CKD. This study does not support a disease-specific effect of ARPKD on growth, at least in the subset of children with mild-to-moderate CKD.

Chronic Kidney Disease in Children: Recent Update

The incidence of end stage of renal disease (ESRD) in US children age 0-19 years is 12.9 per million/year (2012). The economic and social burden of diagnosing, treating and preventing chronic kidney disease (CKD) in children and adults remains substantial. Advances in identifying factors that predict development of CKD and its progression, as well as advances in the management of co-morbid conditions including anemia, cardiovascular disease, growth, mineral and bone disorder, and neurocognitive function are discussed. Despite recent reports from retrospective registry data analysis and multi-center prospective studies which have significantly advanced our knowledge of CKD, and despite advances in the understanding of the pathogenesis, diagnosis and treatment of CKD much work remains to be done to improve the long term outcome of this disease.

Growth hormone therapy in children with chronic renal failure

Growth is impaired in a chronic renal failure. Anemia, acidosis, reduced intake of calories and protein, decreased synthesis of vitamin D and increased parathyroid hormone levels, hyperphosphatemia, renal osteodystrophy and changes in growth hormone-insulin-like growth factor and the gonadotropin-gonadal axis are implicated in this study. Growth is adversely affected by immunosuppressives and corticosteroids after kidney transplantation. Treating metabolic disorders using the recombinant human growth hormone is an effective option for patients with inadequate growth rates.

Anthropometric and biochemical profile of children and adolescents with chronic kidney disease in a predialysis pediatric interdisciplinary program

This is longitudinal retrospective observational cohort study that evaluated anthropometric and biochemical variables of children and adolescents admitted to a Predialysis Interdisciplinary Management Program (PDIMP) responsible for the follow-up of children and adolescents at stages 2 to 4 of chronic kidney disease (CKD) at a tertiary center. One hundred thirty-eight patients with CKD on predialysis treatment with median age at admission of 9 years and the median follow-up time of 5 years were evaluated. Seventy-four (53%) had CKD stage 3 at admission and 70 (51%) reached CKD stage 5 at the end of the follow-up. There was no significant difference between the mean initial and final hemoglobin and serum albumin. However, the final serum bicarbonate presented a significant improvement. Analyses stratified according to clinical variables of interest showed a significant improvement in body mass index (BMI) Z score, especially in the subgroup of children admitted under two years of age. In relation to stature-for-age Z score, data show a significant improvement in stature SD at the end of the study. In conclusion, the present study showed improvement of nutritional status of CKD patients and that the deterioration of renal function was not correlated with BMI-for-age Z score.

Isolated growth hormone deficiency (GHD) in childhood and adolescence: recent advances

The diagnosis of GH deficiency (GHD) in childhood is a multistep process involving clinical history, examination with detailed auxology, biochemical testing, and pituitary imaging, with an increasing contribution from genetics in patients with congenital GHD. Our increasing understanding of the factors involved in the development of somatotropes and the dynamic function of the somatotrope network may explain, at least in part, the development and progression of childhood GHD in different age groups. With respect to the genetic etiology of isolated GHD (IGHD), mutations in known genes such as those encoding GH (GH1), GHRH receptor (GHRHR), or transcription factors involved in pituitary development, are identified in a relatively small percentage of patients suggesting the involvement of other, yet unidentified, factors. Genome-wide association studies point toward an increasing number of genes involved in the control of growth, but their role in the etiology of IGHD remains unknown. Despite the many years of research in the area of GHD, there are still controversies on the etiology, diagnosis, and management of IGHD in children. Recent data suggest that childhood IGHD may have a wider impact on the health and neurodevelopment of children, but it is yet unknown to what extent treatment with recombinant human GH can reverse this effect. Finally, the safety of recombinant human GH is currently the subject of much debate and research, and it is clear that long-term controlled studies are needed to clarify the consequences of childhood IGHD and the long-term safety of its treatment.

The utility of the IGF-I generation test in children with chronic kidney disease

BACKGROUND

To determine if the insulin-like-growth factor (IGF-I) generation test is a marker for growth hormone (GH) sensitivity in children with chronic kidney disease (CKD).

METHODS

This was a randomized cross-over study in which children with CKD received low-dose (0.025 mg/kg/day) and high-dose (0.05 mg/kg/day) GH therapy in the framework of a 7-day IGF-I generation test. Blood samples were collected on day 1 (D1; pre-dose) and on day 8 (D8; post 7 doses) of GH therapy. All subjects received GH for 12 months at 0.05 mg/kg/day. Serum IGF-I was measured by radioimmunometric assay. Normative historic data from healthy children and those with idiopathic short stature were used for comparison.

RESULTS

Sixteen subjects (age 2-13 years) with creatinine clearances of between 25 and 75 ml/min/1.73 m(2) were enrolled. Annualized height velocity for all subjects was 10.3 ± 1.1 cm/year (mean ± standard deviation), with an annual change in height Z score of 0.7 ± 1.0. No correlation was found between the generated serum IGF-I levels (D8 - D1) and creatinine clearances, and with changes in height Z scores. Serum IGF-I levels on D1 and D8 in CKD subjects were lower than normative data, but with adequate IGF-I generation on D8.

CONCLUSIONS

Children with CKD were able to respond to GH therapy with both growth and an increase in serum IGF-I levels, but the IGF-I generation test was not a good predictor of growth response in this cohort.

The impact of short stature on health-related quality of life in children with chronic kidney disease

OBJECTIVES

To compare the health-related quality of life (HRQoL) of children with chronic kidney disease (CKD) and short stature (SS) with that of children with CKD and normal height (NH), to evaluate the impact of catch-up growth and growth hormone (GH) use on HRQoL, and to describe the concordance of perceptions of HRQoL between children with SS and NH and their parents.

STUDY DESIGN

Four hundred eighty-three children and/or parents enrolled in the multicenter Chronic Kidney Disease in Children study who had completed the Pediatric Quality of Life Inventory (Version 4.0) on at least 2 Chronic Kidney Disease in Children study visits composed this substudy population. Participants were dichotomized into NH or SS groups. The demographic characteristics that varied at baseline (sex, glomerular filtration rate, and parent education) were controlled for in the main analysis evaluating the impact of catch-up growth and use of GH on HRQoL.

RESULTS

Multivariate modeling (controlling for confounding variables) revealed a significant association between both catch-up growth and GH use on parent-proxy reports of child physical functioning (P < .05) and social functioning (P < .05). Older children with CKD (15-17 years old) had significantly higher ratings than their parents on the Pediatric Quality of Life Inventory Physical, Emotional, Social, and School Functioning scales compared with younger children (8-14 years old).

CONCLUSION

The finding that height gains and GH use are associated with increases in physical and social functioning by parent report provides additional support for interventions to improve height in children with CKD. The importance of evaluating both the parent and child perceptions of HRQoL is supported by our results.

Growth and growth hormone treatment in children with chronic diseases

Growth hormone has been available for treatment of various conditions for over 50 years. There have been a number of chronic disease states in which it has been used, such as chronic kidney disease, which became a US Food and Drug Administration (FDA)-approved indication in 1993. For other chronic disease states there have been clinical studies supporting its use, but they have not yet been approved as a indications by the FDA. Examples of such diseases are cystic fibrosis, chronic arthritis, short bowel syndrome, burn trauma, and hypophosphatemic rickets.

The consequences of chronic kidney disease on bone metabolism and growth in children

Growth retardation, decreased final height and renal osteodystrophy (ROD) are common complications of childhood chronic kidney disease (CKD), resulting from a combination of abnormalities in the growth hormone (GH) axis, vitamin D deficiency, hyperparathyroidism, hypogonadism, inadequate nutrition, cachexia and drug toxicity. The impact of CKD-associated bone and mineral disorders (CKD-MBD) may be immediate (serum phosphate/calcium disequilibrium) or delayed (poor growth, ROD, fractures, vascular calcifications, increased morbidity and mortality). In 2012, the clinical management of CKD-MBD in children needs to focus on three main objectives: (i) to provide an optimal growth in order to maximize the final height with an early management with recombinant GH therapy when required, (ii) to equilibrate calcium/phosphate metabolism so as to obtain acceptable bone quality and cardiovascular status and (iii) to correct all metabolic and clinical abnormalities that can worsen bone disease, growth and cardiovascular disease, i.e. metabolic acidosis, anaemia, malnutrition and 25(OH)vitamin D deficiency. The aim of this review is to provide an overview of the mineral, bone and vascular abnormalities associated with CKD in children in terms of pathophysiology, diagnosis and clinical management.

Uric acid and IGF1 as possible determinants of FGF23 metabolism in children with normal renal function

BACKGROUND

Fibroblast growth factor 23 (FGF23) is a phosphaturic hormone and a suppressor of renal 1α hydroxylase. Although circulating values of FGF23 are increased in early chronic kidney disease (CKD), the interplay between FGF23 levels, growth and nutritional biomarkers has not been evaluated in children with normal renal function.

METHODS

We performed a secondary analysis of the cross-sectional observational INU23 study in 98 children (51 boys, mean age 10.5 ± 3.9 years) with preserved renal function (glomerular filtration rate (GFR) 114 ± 14 ml/min/1.73 m(2)).

RESULTS

In bivariate analyses, C-terminal FGF23 levels were positively related to phosphorus and uric acid levels. Intact FGF23 levels were positively associated with uric acid and insulin growth factor 1 (IGF1) levels, with similar results for age, body mass index (BMI), and 25OH vitamin D (25(OH)D). By multivariable analyses, 25(OH)D, uric acid, and phosphorus were independent predictors of C-terminal FGF23, while 25(OH)D, uric acid, and IGF1 were independent predictors of intact FGF23.

CONCLUSIONS

In children with preserved kidney function, the association between FGF23, uric acid, and IGF1 suggests that FGF23 could be an early nutritional indicator of high protein and phosphate intake. The association between FGF23 and IGF1 also suggests a relationship between FGF23 and growth, and warrants further investigation.

Functional and total IGFBP3 for the assessment of disorders of the GH/IGF1 axis in children with chronic kidney disease, GH deficiency, or short stature after SGA status at birth

OBJECTIVE

IGFBP3 immunoreactivity may appear elevated in patients with chronic kidney disease (CKD), in part due to accumulation of low molecular fragments. The importance of these IGFBP3 variants for binding and inactivation of IGF1 and their relevance for the impaired growth of uremic children are unclear. Nevertheless, IGFBP3, measured as total (t-)IGFBP3, is frequently used as a diagnostic parameter in pediatric CKD patients. A new assay for functional (f-)IGFBP3 exclusively detects IGFBP3 capable of IGF binding. The aim of the study was to evaluate the significance of f-IGFBP3 measurements for the assessment of uremic abnormalities of the GH/IGF1 axis.

DESIGN

Prospective cross-sectional study.

METHODS

t-IGFBP3, f-IGFBP3, and IGF1 were measured in pediatric CKD patients, including patients with CKD stage 3-4 not on dialysis (CKD, n=33), on dialysis treatment (DT, n=26), patients after renal transplantation (RTx, n=89), healthy children (n=29), children with GH deficiency (GHD, n=42), and small for gestational age (SGA) children (SGA, n=34).

RESULTS

Mean t-IGFBP3 SDS was elevated in CKD, DT, and RTx children compared with controls and GHD patients (P≤0.0004). Highest values were reached in DT (P<0.0001 vs all groups). In contrast, mean f-IGFBP3 was similar in all groups (P=0.30).

CONCLUSIONS

Pediatric CKD patients displayed elevated serum concentrations of t-IGFBP3 but not f-IGFBP3, supporting the hypothesis that IGFBP3 fragments not binding IGF1 accumulate during uremia. f-IGFBP3 is an indicator of IGFBP3 fragmentation and seems to reflect IGF1 binding in CKD better than t-IGFBP3. However, the role of f-IGFBP3 for the diagnosis of disturbances of the GH/IGF hormonal axis appears to be limited.

HTLV-1 positive and negative T cells cloned from infected individuals display telomerase and telomere genes deregulation that predominate in activated but untransformed CD4+ T cells

Untransformed HTLV-1 positive CD4(+) cells from infected individuals are selected for expressing tax and displaying morphological features consistent with telomere dysfunctions. We show that in resting HTLV-1 positive CD4(+) cells cloned from patients, hTERT expression parallels tax expression and cell cycling. Upon activation, these cells dramatically augment tax expression, whereas their increase in telomerase activity is about 20 times lower than that of their uninfected counterpart. Activated HTLV-1 positive CD4(+) but not uninfected CD4(+) or CD8(+) clones also repress the transcription of TRF1, TPP1, TANK1, POT1, DNA-PKc and Ku80. Both infected and uninfected lymphocytes from infected individuals shared common telomere gene deregulations toward a pattern consistent with premature senescence. ATLL cells displayed the highest telomerase activity (TA) whereas recovered a telomere gene transcriptome close to that of normal CD4(+) cells. In conclusion HTLV-1-dependent telomere modulations seem involved in clonal expansion, immunosuppression, tumor initiation and progression.

Growth in chronic kidney disease

Poor growth is a common sequela of CKD in childhood. It not only affects the psychosocial development of a child but also has significant effects even in the adult life. The multifactorial etiology and severe consequences of growth failure in CKD warrant evaluation of all the modifiable and nonmodifiable causes. Treatment strategies must be directed toward the specific factors for each child with CKD. Among the various metabolic, nutritional, and hormonal disturbances complicating CKD, disordered growth hormone (GH) and insulin-like growth factor-1 axis are important contributors toward poor growth in children with CKD. CKD is recognized as a state of GH resistance rather than GH deficiency, with multiple mechanisms contributing to this GH resistance. Recombinant GH (rGH) therapy can be used in this population to accelerate growth velocity. Although its use has been shown to be effective and safe in children with CKD, there continues to be some uncertainty and reluctance among practitioners and families regarding its usage, thereby resulting in a surprisingly low use in children with CKD. This review focuses on the pathogenesis of growth failure, its effect, and management strategies in children with CKD.

Telomere deregulations possess cytogenetic, phenotype, and prognostic specificities in acute leukemias

OBJECTIVE

Telomeres are protected by tightly regulated factors and elongated by telomerase. Short and/or deprotected chromosomes are recombinogenic and thereby cancer prone.

MATERIALS AND METHODS

Together with the quantification of telomerase activity (TA), measuring telomere length (TL) and expression of the genes that govern telomere protection and elongation are useful for assessing telomere homeostasis.

RESULTS

By these means we demonstrate that TL, hTERT, and TA are in the order acute myelogenous leukemia (AML) > T-cell acute lymphoblastic leukemia (T-ALL) > B-cell acute lymphoblastic leukemia (B-ALL) > T-ALL > AML, and B-ALL > AML > T-ALL. AML0 and AML3 display the lowest amounts of hTERT transcripts, and ALL and AML cells with cytogenetic abnormalities possess the shortest telomeres. hTERT expression includes phenotype-specific RNA maturation and correlates with TA but not with TL. A wide ratio of TA to hTERT expression between leukemia subtypes suggests phenotype-specific hTERT post-transcriptional deregulations. B- and T-ALL overexpress Ku70 and Pinx1, T-ALL PTOP and RAP1, and B-ALL TRF2, the expression of which is significantly higher in cases with abnormal karyotype. hTERT transcription and TL correlate with response to intensive chemotherapy, and hTERT and RAD50 are independent prognostic factors for survival.

CONCLUSIONS

Each leukemia subtype possesses specific telomere dysregulations that rely on phenotype, karyotype, response to treatment, and survival.

Predicting the response to growth hormone treatment in short children with chronic kidney disease

CONTEXT

Short stature in children with chronic kidney disease (CKD) is due to various underlying congenital or acquired renal disorders resulting in variable impairment of renal function and variable response to GH treatment.

OBJECTIVE

It was the aim to develop a mathematical model that allows the prediction of the individual growth response and to identify nonresponders.

DESIGN

Data from 208 prepubertal children on conservative or dialysis treatment in a large pharmaco-epidemiological survey, the KIGS (Pfizer International Growth Database), were used for the model and data from 67 similar CKD patients registered at the Dutch Growth Research Foundation for validation.

RESULTS

Annualized height velocity (centimeters per year) during the first year of GH treatment was best predicted by age at start, weight sd score, underlying renal disorder (hereditary kidney disorder), glomerular filtration rate (at baseline), and GH dosage. Using these parameters, the final model explained 37% of the overall variability of growth response. Standard error of the estimates was 1.6 cm. Age was the most important predictor of growth response (20.3% of variability) followed by weight sd score at start, and 27.2% of the variability of the second-year response could be predicted by the first-year response and glomerular filtration rate. Nonresponders of the validation group could be correctly identified.

CONCLUSION

Based on simple clinical variables, a robust prediction model was developed that provides realistic expectations of individual growth response to GH in short children with CKD. The model will help in identifying nonresponders and to tailor treatment strategies.

The effect of rhGH on height velocity and BMI in children with CKD: a report of the NAPRTCS registry

The aim of this investigation was to evaluate the impact of recombinant human growth hormone (rhGH) therapy on height velocity (HV), estimated glomerular filtration rate (eGFR) and body mass index (BMI) in a large cohort of children with chronic kidney disease (CKD). We reviewed longitudinal data from patients enrolled in the chronic renal insufficiency registry of the North American Pediatric Renal Trials and Collaborative Studies (NAPRTCS). Of the 7189 patients enrolled in the registry, 827 (11.5%) received rhGH. A total of 787 children with CKD previously rhGH naïve who received rhGH for 1-4 years (median 1.5 years) were paired with 787 control patients, and over 100 of the case-controls were followed for 4 years. The control group was matched for age, gender, height and length of time in the NAPRTCS registry. Height velocity was also compared to the general U.S. population. The eGFR of the treated group (37.5 ml/min per 1.73 m(2)) was significantly less than that of the control group (42.3 ml/min per 1.73 m(2); p < 0.001). The rhGH-treated group had a significantly greater HV standard deviation score (SDS) than the control group (p < 0.01) at each 6-months post-rhGH treatment initiation point for 2.5 years (p < 0.007). Among 220 pairs at 2 years, the height SDS of the rhGH group was 0.56 SDS higher than that of the control group (p < 0.05). Treatment with rhGH had no significant impact on the BMI or eGFR. As demonstrated in smaller cohorts, rhGH usage is associated with improved HV in children with CKD. In contrast, rhGH does not appear to have any impact on BMI or kidney function in this population of patients.

[Short stature in chronic kidney disease: physiopathology and treatment with growth hormone]

Growth failure is frequent and a clinically important issue in children with chronic kidney disease (CKD). Many factors contribute to impaired growth in these children, including abnormalities in the growth hormone (GH)--insulin-like growth factor 1 (IGF-1) axis, malnutrition, acidosis, renal bone disease and glucocorticoid associated treatment. The management of growth failure in children with CKD is complicated by the presence of other-disease related complications requiring medical intervention. Despite evidence of GH efficacy and safety in this population, this therapy is still underutilized. This review shows the impact, the causes and the treatment of growth failure in children with CKD.

Current advances in chronic kidney disease in children: growth, cardiovascular, and neurocognitive risk factors

Linear growth and neurocognitive development are two of the most important differences between adults and children, in terms of clinical issues that must be addressed in patients with chronic kidney disease (CKD). Correction of metabolic acidosis, nutritional deficiency, and renal osteodystrophy improve linear growth, but many children require administration of growth hormone to achieve normal growth. A variety of neurocognitive deficits occur in children with CKD, although there has been an improvement in outcome via improved dialysis, correction of malnutrition, and decreased aluminum exposure. Although growth and neurocognitive development are delayed, cardiovascular complications are accelerated in children with CKD, and are reflected in a dramatic increase in cardiovascular mortality compared with healthy children. Other early cardiovascular complications in children with CKD include left ventricular hypertrophy, cardiac dysfunction, and vascular calcifications.

Gene therapy by electroporation for the treatment of chronic renal failure in companion animals

Background

Growth hormone-releasing hormone (GHRH) plasmid-based therapy for the treatment of chronic renal failure and its complications was examined. Companion dogs (13.1 ± 0.8 years, 29.4 ± 5.01 kg) and cats (13.2 ± 0.9 years, 8.5 ± 0.37 kg) received a single 0.4 mg or 0.1 mg species-specific plasmid injection, respectively, intramuscularly followed by electroporation, and analyzed up to 75 days post-treatment; controls underwent electroporation without plasmid administration.

Results

Plasmid-treated animals showed an increase in body weight (dogs 22.5% and cats 3.2%) compared to control animals, and displayed improved quality of life parameters including significant increases in appetite, activity, mentation and exercise tolerance levels. Insulin-like growth factor I (IGF-I, the downstream effector of GHRH) levels were increased in the plasmid treated animals. Hematological parameters were also significantly improved. Protein metabolism changes were observed suggesting a shift from a catabolic to an anabolic state in the treated animals. Blood urea nitrogen and creatinine did not show any significant changes suggesting maintenance of kidney function whereas the control animal's renal function deteriorated. Treated animals survived longer than control animals with 70% of dogs and 80% of cats surviving until study day 75. Only 17% and 40% of the control dogs and cats, respectively, survived to day 75.

Conclusion

Improved quality of life, survival and general well-being indicate that further investigation is warranted, and show the potential of a plasmid-based therapy by electroporation in preventing and managing complications of renal insufficiency.

Long-term outcome of chronic dialysis in children

As the prevalence of children on renal replacement therapy (RRT) increases world wide and such therapy comprises at least 2% of any national dialysis or transplant programme, it is essential that paediatric nephrologists are able to advise families on the possible outcome for their child on dialysis. Most children start dialysis with the expectation that successful renal transplantation is an achievable goal and will provide the best survival and quality of life. However, some will require long-term dialysis or may return intermittently to dialysis during the course of their chronic kidney disease (CKD). This article reviews the available outcome data for children on chronic dialysis as well as extrapolating data from the larger adult dialysis experience to inform our paediatric practice. The multiple factors that may influence outcome, and, particularly, those that can potentially be modified, are discussed.

Clinical outcome of children with chronic kidney disease in a pre-dialysis interdisciplinary program

The purpose of this retrospective cohort study was to describe the outcome of 107 patients with chronic kidney disease (CKD) admitted to a pre-dialysis interdisciplinary management program from 1990 to 2006. The events of interest were progression to CKD stage 5 (renal survival), patient survival, hypertension, and somatic growth. Survival was studied by the Kaplan-Meier method. Patients were classified into four groups according to their primary renal disease: congenital nephro-uropathies; glomerular diseases; cystic disease, and miscellaneous. Median follow-up time was 94 months [Interquartile (IQ) range 38-145]. The probability of reaching CKD stage 5 was estimated to be 36% by 5 years after admission. As a whole, the mean estimated glomerular filtration rate (GFR) decrease per year was 5.8 ml/min per 1.73 m(2) body surface area [standard deviation (SD) 12.4]. The glomerular diseases group showed a median rate of GFR deterioration of 10 ml/min per 1.73 m(2) per year (IQ range -24 to -5.7), whereas the median rate of GFR deterioration for the groups with cystic diseases, congenital nephro-uropathies, and miscellanea were 2.5 ml/min (IQ range -10 to +0.34), 2.2 ml/min (IQ range -5.0 to -0.52), and 0.36 ml/min (IQ range -2.5 to +2.6), respectively (P < 0.001). The results of this study support the view that children and adolescents with glomerular diseases present a faster deterioration of renal function. Therefore, patients with glomerular diseases need to be referred early to a pediatric nephrology center so that suboptimal pre-dialysis care might possibly be avoided.

Long-term results of rhGH treatment in children with renal failure: experience of the French Society of Pediatric Nephrology

Few publications have described the long-term effects of recombinant human growth hormone (rhGH) in uremic patients. This study reports the results of rhGH therapy at the end of treatment and at adult age in 178 French patients. At enrollment, 63 patients were under conservative treatment (CT), 40 under hemodialysis (HD), and 75 had a functioning renal transplant (RT). Under rhGH treatment, height velocities (HV) significantly increased in all patients, but the effect was significantly better in the CT group. The HV gain (HV under rhGH-HV before treatment) was similar in all three groups. Increases in HV allowed height standard deviation scores (SDS) catch up, and this effect persisted over a 5-year period. SDS height at the completion of treatment was significantly related to group (best in CT) and response to treatment during the first year. Data on adult height was available for 102 patients. Mean adult height was 162.2 cm in men and 152.9 cm in women, and 46% were > -2 SDS for height. Adult height SDS was correlated with height SDS and spontaneous HV before treatment and effect of treatment. Analysis of adult height in the 49 patients who entered the protocol with a height SDS between -2 and -3 (the current recommendation for rhGH use) revealed that 65% had an adult-height SDS >-2. These adult heights were significantly better if compared with historical cohorts of patients not treated by rhGH; rhGH significantly improves the adult-height prognosis of uremic patients suffering from growth retardation. Early rhGH administration during CT gives better height SDS at both the end of rhGH therapy and in adulthood.

Obstacles to the prescribing of growth hormone in children with chronic kidney disease

Despite its effectiveness, recombinant human growth hormone (rhGH) is under-utilized in short children with chronic kidney disease (CKD). We conducted a multicenter study to explore the obstacles preventing children with CKD from receiving rhGH. We investigated the use of rhGH in 307 children with CKD from seven pediatric nephrology centers. Among the 110 patients who fell below the 5th percentile, 56 (51%) had not received rhGH. The most common reasons given for these children not receiving rhGH were family refusal, secondary hyperparathyroidism, and non-compliance. However, no explanation was apparent for 25% of the short children with CKD. Boys were more likely than girls to receive rhGH (65% vs 31%; P = 0.002). Use of rhGH was similar in African Americans and non-Hispanic Whites. Children who had received rhGH achieved a 0.5 increase in height z-score in the first year after the initiation of rhGH therapy. Children who had not received rhGH achieved a 0.03 increase in height z-score during the first year after falling below the 5th percentile (P = 0.005 vs the children who had received rhGH). Waiting for insurance company approval led to a significant delay in the initiation of rhGH treatment in 18% of patients. The fact that more than 50% of short children with CKD did not receive rhGH is secondary to multiple factors, many of which may be amenable to intervention efforts.

Factors predicting the near-final height in growth hormone-treated children and adolescents with chronic kidney disease

CONTEXT

GH therapy is an accepted measure to increase adult height in young prepubertal patients suffering from growth failure related to chronic kidney disease (CKD). The impact of GH therapy on final height (FH) in CKD patients of pubertal age is unclear.

OBJECTIVE

This study set out to analyze near-FH in a cohort of GH-treated CKD patients.

DESIGN, SETTINGS, AND PATIENTS

Of 240 evaluable patients in the Pfizer International Growth Database (KIGS) with CKD, 39% were prepubertal and 61% were pubertal at baseline; 45% were on conservative treatment for CKD, 28% were on dialysis, and 27% were in the period after renal transplantation.

MAIN OUTCOME MEASURES

Near-FH, relation to pubertal stage, and factors predictive of growth response were the main outcome measures.

RESULTS

Mean height sd scores increased continuously during GH treatment until near-FH by 1.2 and 1.6 in boys and girls, respectively. Mean near-FH differed significantly from prepubertal patients showing severely delayed puberty (-3.6), late pubertal patients (-2.9), early pubertal patients (-2.2), and prepubertal patients with normal onset of puberty (-2.0). The initial degree of stunting, degree of bone age retardation, duration of GH therapy, time spent on conservative treatment/dialysis, pubertal delay (>2 sd), gender, and age at start of GH treatment were significant predictors of growth response to GH therapy, explaining between 33 and 61% of the overall variability.

CONCLUSIONS

Long-term GH therapy of CKD patients in prepubertal and pubertal age results in an increased adult height, but response is diminished in patients on dialysis and/or with severely delayed puberty.