Nutrition and growth in children with chronic kidney disease

Combating chronic kidney disease-associated cachexia: A literature review of recent therapeutic approaches

In 2008, the Society on Sarcopenia, Cachexia, and Wasting Disorders introduced a generic definition for all types of cachexia: "a complex metabolic syndrome associated with the underlying illness characterized by a loss of muscle, with or without fat loss". It is well-known that the presence of inflammatory burden in end-stage renal disease (ESRD) patients may lead to the evolution of cachexia. Since the etiology of cachexia in chronic kidney disease (CKD) is multifactorial, thus the successful treatment must involve several concomitant measures (nutritional interventions, appetite stimulants, and anti-inflammatory pharmacologic agents) to provide integrated effective therapeutic modalities to combat causative factors and alleviate the outcomes of patients. Given the high mortality rate associated with cachexia, developing new therapeutic modalities are prerequisite for ameliorating patients with CKD worldwide. The present review aims to discuss some therapeutic strategies and provide an update on advances in nutritional approaches to counteract cachexia.

Patient, Parental, and Health Professional Perspectives on Growth in Children With CKD

RATIONALE & OBJECTIVE

Growth failure is a common problem among children with chronic kidney disease (CKD). Reduced height is associated with psychosocial burden, social stigma, and impaired quality of life. This study describes the aspects of growth impairment that are most impactful from the perspectives of children with CKD, their parents, and health professionals.

STUDY DESIGN

Qualitative study.

SETTINGS & PARTICIPANTS

120 children with CKD (aged 8-21 years), 250 parents, and 445 health professionals from 53 countries who participated in 16 focus groups, 2 consensus workshops, and a Delphi survey.

ANALYTICAL APPROACH

A thematic analysis of all qualitative data concerning growth from the Standardized Outcomes in Nephrology-Children and Adolescents (SONG-Kids) initiative.

RESULTS

We identified 5 themes: diminishing psychological well-being (compared to and judged by peers, tired of explaining to others, damaging self-esteem), constrained life participation and enjoyment (deprived of normal school experiences, excluded from sports or competing at a disadvantage, impaired quality of life in adulthood); grappling with impacts of symptoms and treatment (difficulty understanding short stature and accessing help, lack of appetite, uncertainty regarding bone pains, medication side effects, burden of growth hormone treatment); facilitating timely interventions and optimizing outcomes (early indicator of disease, assessing management, maximizing transplant outcomes, minimizing morbidity); and keeping growth and health priorities in perspective (quality of life and survival of utmost priority, achieved adequate height).

LIMITATIONS

Only English-speaking participants were included.

CONCLUSIONS

Impaired growth may diminish psychological well-being, self-esteem, and participation in daily activities for children with CKD. Balancing different treatments that can affect growth complicates decision making. These findings may inform the psychosocial support needed by children with CKD and their caregivers to address concerns about growth.

PLAIN-LANGUAGE SUMMARY

Children with chronic kidney disease (CKD) are often much shorter than their peers and may experience poorer mental health and quality of life. To understand the specific important issues on how growth impairment affects these children, we collected qualitative data from the Standardized Outcomes in Nephrology-Children and Adolescents (SONG-Kids) initiative and analyzed perspectives on growth from patients, parents, and health professionals. These data revealed impaired psychological health, reduced enjoyment during school and sports, difficulty dealing with medication side effects and growth hormone treatment, and concerns related to tracking health status and kidney transplant outcomes. These findings may inform the psychosocial support needed by children with CKD and their caregivers to address concerns about growth and overall health.

The effect of gastrostomy tube feeding on growth in children with chronic kidney disease and on dialysis

BACKGROUND

Gastrostomy tube (GT) feeding is used to promote nutrition and growth in children with chronic kidney disease (CKD). We explored the relationship between gastrostomy feeding and growth parameters in children with CKD, looking specifically at the nutritional composition of feeds.

METHODS

Children with CKD stages 3-5 or on dialysis in a tertiary children's kidney unit were studied. Data on anthropometry, biochemistry, and nutritional composition of feeds were collected from the time of GT insertion for 3 years or until transplantation.

RESULTS

Forty children (18 female) were included. Nineteen children were on peritoneal dialysis, 8 on hemodialysis, and 13 had CKD stages 3-5. The median (interquartile range [IQR]) age at GT insertion was 1.26 (0.61-3.58) years, with 31 (77.5%) under 5 years of age. The median duration of gastrostomy feeding was 5.32 (3.05-6.31) years. None received growth hormone treatment. Children showed a significant increase in weight standard deviation score (SDS) (p = 0.0005), weight-for-height SDS (p = 0.0007) and body mass index (BMI) SDS (p < 0.0001). None of the children developed obesity. Although not statistically significant, the median height-SDS increased into the normal range (from -2.29 to -1.85). Weight-SDS positively correlated with the percentage of energy requirements from feeds (p = 0.02), and the BMI-SDS correlated with the percentage of total energy intake as fat (p < 0.001).

CONCLUSION

GT feeding improves weight-SDS and BMI-SDS without leading to obesity. GT feeding improved height-SDS but this did not reach statistical significance, suggesting that factors in addition to nutritional optimization need to be considered for statural growth.

Growth in children with chronic kidney disease and associated risk factors for short stature

INTRODUCTION

Growth failure in chronic kidney disease is related to high morbidity and mortality. Growth retardation in this disease is multifactorial. Knowing the modifiable factors and establishing strategies to improve care for affected children is paramount.

OBJECTIVES

To describe growth patterns in children with chronic kidney disease and the risk factors associated with short stature.

METHODS

We retrospectively analyzed anthropometric and epidemiological data, birth weight, prematurity, and bicarbonate, hemoglobin, calcium, phosphate, alkaline phosphatase, and parathormone levels of children with stages 3-5 CKD not on dialysis, followed for at least one year.

RESULTS

We included 43 children, the majority of which were boys (65%). The mean height/length /age z-score of the children at the beginning and follow-up was -1.89 ± 1.84 and -2.4 ± 1.67, respectively (p = 0.011). Fifty-one percent of the children had short stature, and these children were younger than those with adequate stature (p = 0.027). PTH levels at the beginning of the follow-up correlated with height/length/age z-score. A sub-analysis with children under five (n = 17) showed that 10 (58.8%) of them failed to thrive and had a lower weight/age z-score (0.031) and lower BMI/age z-score (p = 0.047).

CONCLUSION

Children, particularly younger ones, with chronic kidney disease who were not on dialysis had a high prevalence of short stature. PTH levels were correlated with height z-score, and growth failure was associated with worse nutritional status. Therefore, it is essential to monitor the growth of these children, control hyperparathyroidism, and provide nutritional support.

Chronic Kidney Disease and Growth Failure in Children

Chronic kidney disease (CKD) is a significant challenge for pediatric endocrinologists, as children with CKD may present a variety of endocrine complications. Growth failure is common in CKD, and its severity is correlated with the degree of renal insufficiency. Management strategies include addressing reversible comorbidities, optimizing nutrition, and ensuring metabolic control. Kidney replacement therapy, including transplantation, determines a significant improvement in growth. According to a recent Consensus Statement, children with CKD stage 3-or on dialysis older >6 months-are eligible for treatment with recombinant growth hormone (rGH) in the case of persistent growth failure. Treatment with rGH may be considered for those with height between the 3rd and 10th percentile and persistent growth deceleration. In children who received kidney transplantation but continue to experience growth failure, initiation of GH therapy is recommended one year post-transplantation if spontaneous catch-up growth does not occur and steroid-free immunosuppression is not an option. In children with CKD, due to nephropathic cystinosis and persistent growth failure, GH therapy should be considered at all stages of CKD. Potential adverse effects and benefits must be regularly assessed during therapy. Treatment with GH is safe in children with CKD. However, its general efficacy is still controversial. All possible problems with a negative impact on growth should be timely addressed and resolved, whenever possible with a personalized approach to the patient. GH therapy may be useful in promoting catch-up growth in children with residual growth potential. Future research should focus on refining effective therapeutic strategies and establishing consensus guidelines to optimize growth outcomes in this population.

Indoxyl Sulfate Contributes to Impaired Height Velocity in (Pre)School Children

Introduction

Growth failure is considered the most important clinical outcome parameter in childhood chronic kidney disease (CKD). Central to the pathophysiology of growth failure is the presence of a chronic proinflammatory state, presumed to be partly driven by the accumulation of uremic toxins. In this study, we assessed the association between uremic toxin concentrations and height velocity in a longitudinal multicentric prospective pediatric CKD cohort of (pre)school-aged children and children during pubertal stages.

Methods

In a prospective, multicentric observational study, a selection of uremic toxin levels of children (aged 0-18 years) with CKD stage 1 to 5D was assessed every 3 months (maximum 2 years) along with clinical growth parameters. Linear mixed models with a random slope for age and a random intercept for child were fitted for height (in cm and SD scores [SDS]). A piecewise linear association between age and height was assumed.

Results

Data analysis included data from 560 visits of 81 children (median age 9.4 years; 2/3 male). In (pre)school aged children (aged 2-12 years), a 10% increase in concurrent indoxyl sulfate (IxS, total) concentration resulted in an estimated mean height velocity decrease of 0.002 SDS/yr (P < 0.05), given that CKD stage, growth hormone (GH), bicarbonate concentration, and dietary protein intake were held constant. No significant association with height velocity was found in children during pubertal stages (aged >12 years).

Conclusion

The present study demonstrated that, especially IxS contributes to a lower height velocity in (pre)school children, whereas we could not find a role for uremic toxins with height velocity during pubertal stages.

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.

Nutrition in Children With Chronic Kidney Disease: How to Thrive?

The nutritional status and management of children with chronic kidney disease (CKD) are complex and require a combined pediatric nephrology team work approach with physicians, nutritionists, nurses, and physical/occupational therapists. Prospective observational studies such as Children with CKD in the US, the 4C study in Europe and the International Pediatric Peritoneal Dialysis Network have advanced the field. However, most recommendations and guidelines from international task forces such as Kidney Diseases Improving Global Outcomes and Pediatric Renal Nutrition Taskforce are opinion-based rather than evidence-based. There is exciting ongoing research to improve nutrition in children with CKD to help them thrive.

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.

Associations of longitudinal height and weight with clinical outcomes in pediatric kidney replacement therapy: results from the ESPN/ERA Registry

BACKGROUND

Associations between anthropometric measures and patient outcomes in children are inconsistent and mainly based on data at kidney replacement therapy (KRT) initiation. We studied associations of height and body mass index (BMI) with access to kidney transplantation, graft failure, and death during childhood KRT.

METHODS

We included patients < 20 years starting KRT in 33 European countries from 1995-2019 with height and weight data recorded to the ESPN/ERA Registry. We defined short stature as height standard deviation scores (SDS) < -1.88 and tall stature as height SDS > 1.88. Underweight, overweight and obesity were calculated using age and sex-specific BMI for height-age criteria. Associations with outcomes were assessed using multivariable Cox models with time-dependent covariates.

RESULTS

We included 11,873 patients. Likelihood of transplantation was lower for short (aHR: 0.82, 95% CI: 0.78-0.86), tall (aHR: 0.65, 95% CI: 0.56-0.75), and underweight patients (aHR: 0.79, 95%CI: 0.71-0.87). Compared with normal height, patients with short and tall statures showed higher graft failure risk. All-cause mortality risk was higher in short (aHR: 2.30, 95% CI: 1.92-2.74), but not in tall stature. Underweight (aHR: 1.76, 95% CI: 1.38-2.23) and obese (aHR: 1.49, 95% CI: 1.11-1.99) patients showed higher all-cause mortality risk than normal weight subjects.

CONCLUSIONS

Short and tall stature and being underweight were associated with a lower likelihood of receiving a kidney allograft. Mortality risk was higher among pediatric KRT patients with a short stature or those being underweight or obese. Our results highlight the need for careful nutritional management and multidisciplinary approach for these patients. A higher resolution version of the Graphical abstract is available as Supplementary information.

Symptoms for early diagnosis of chronic kidney disease in children - a machine learning-based score

The objective of this study was to reveal the signs and symptoms for the classification of pediatric patients at risk of CKD using decision trees and extreme gradient boost models for predicting outcomes. A case-control study was carried out involving children with 376 chronic kidney disease (cases) and a control group of healthy children (n = 376). A family member responsible for the children answered a questionnaire with variables potentially associated with the disease. Decision tree and extreme gradient boost models were developed to test signs and symptoms for the classification of children. As a result, the decision tree model revealed 6 variables associated with CKD, whereas twelve variables that distinguish CKD from healthy children were found in the "XGBoost". The accuracy of the "XGBoost" model (ROC AUC = 0.939, 95%CI: 0.911 to 0.977) was the highest, while the decision tree model was a little lower (ROC AUC = 0.896, 95%CI: 0.850 to 0.942). The cross-validation of results showed that the accuracy of the evaluation database model was like that of the training.

CONCLUSION

In conclusion, a dozen symptoms that are easy to be clinically verified emerged as risk indicators for chronic kidney disease. This information can contribute to increasing awareness of the diagnosis, mainly in primary care settings. Therefore, healthcare professionals can select patients for more detailed investigation, which will reduce the chance of wasting time and improve early disease detection.

WHAT IS KNOWN

• Late diagnosis of chronic kidney disease in children is common, increasing morbidity. • Mass screening of the whole population is not cost-effective.

WHAT IS NEW

• With two machine-learning methods, this study revealed 12 symptoms to aid early CKD diagnosis. • These symptoms are easily obtainable and can be useful mainly in primary care settings.

Mineral Metabolism in Children: Interrelation between Vitamin D and FGF23

Fibroblast growth factor 23 (FGF23) was identified at the turn of the century as the long-sought circulating phosphatonin in human pathology. Since then, several clinical and experimental studies have investigated the metabolism of FGF23 and revealed its relevant pathogenic role in various diseases. Most of these studies have been performed in adult individuals. However, the mineral metabolism of the child is, to a large extent, different from that of the adult because, in addition to bone remodeling, the child undergoes a specific process of endochondral ossification responsible for adequate mineralization of long bones’ metaphysis and growth in height. Vitamin D metabolism is known to be deeply involved in these processes. FGF23 might have an influence on bones’ growth as well as on the high and age-dependent serum phosphate concentrations found in infancy and childhood. However, the interaction between FGF23 and vitamin D in children is largely unknown. Thus, this review focuses on the following aspects of FGF23 metabolism in the pediatric age: circulating concentrations’ reference values, as well as those of other major variables involved in mineral homeostasis, and the relationship with vitamin D metabolism in the neonatal period, in vitamin D deficiency, in chronic kidney disease (CKD) and in hypophosphatemic disorders.

Malnutrition Patterns in Children with Chronic Kidney Disease

Malnutrition is frequent in children with chronic kidney disease (CKD). Apart from undernutrition and protein energy wasting (PEW), overnutrition prevalence is rising, resulting in fat mass accumulation. Sedentary behavior and unbalanced diet are the most important causal factors. Both underweight and obesity are linked to adverse outcomes regarding renal function, cardiometabolic risk and mortality rate. Muscle wasting is the cornerstone finding of PEW, preceding fat loss and may lead to fatigue, musculoskeletal decline and frailty. In addition, clinical data emphasize the growing occurrence of muscle mass and strength deficits in patients with fat mass accumulation, attributed to CKD-related wasting processes, reduced physical activity and possibly to obesity-induced inflammatory diseases, leading to sarcopenic obesity. Moreover, children with CKD are susceptible to abdominal obesity, resulting from high body fat distribution into the visceral abdomen compartment. Both sarcopenic and abdominal obesity are associated with increased cardiometabolic risk. This review analyzes the pathogenetic mechanisms, current trends and outcomes of malnutrition patterns in pediatric CKD. Moreover, it underlines the importance of body composition assessment for the nutritional evaluation and summarizes the advantages and limitations of the currently available techniques. Furthermore, it highlights the benefits of growth hormone therapy and physical activity on malnutrition management.

Nutritional Assessment and Support in Children with Chronic Kidney Disease: The Benefits of Working with a Registered Dietitian

BACKGROUND

An unbalanced dietary pattern, characterized by high animal protein content: may worsen metabolic control, accelerate renal deterioration and consequently aggravate the stage of the chronic kidney disease (CKD) in pediatric patients with this condition.

AIM

to assess the effect of a registered dietitian (RD) intervention on the CKD children's eating habits.

METHODS

Anthropometric and dietetic parameters, obtained at baseline and 12 months after implementing healthy eating and nutrition education sessions, were compared in 16 patients (50% girls) of 8.1 (1-15) years. On each occasion, anthropometry, 3-day food records and a food consumption frequency questionnaire were carried out. The corresponding relative intake of macro- and micronutrients was contrasted with the current advice by the European Food Safety Authority (EFSA) and with consumption data obtained using the Spanish dietary guidelines. Student's paired t-test, Wilcoxon test and Mc Nemar test were used.

RESULTS

At Baseline 6% were overweight, 69% were of normal weight and 25% were underweight. Their diets were imbalanced in macronutrient composition. Following nutritional education and dietary intervention 63%, 75% and 56% met the Dietary Reference Values requirements for fats, carbohydrates and fiber, respectively, but not significantly. CKD children decreased protein intake (p < 0.001), increased dietary fiber intake at the expense of plant-based foods consumption (p < 0.001) and a corresponding reduction in meat, dairy and processed food intake was noticed. There were no changes in the medical treatment followed or in the progression of the stages.

CONCLUSIONS

RD-led nutrition intervention focused on good dieting is a compelling helpful therapeutic tool to improve diet quality in pediatric CKD patients.

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

Growth retardation is a major complication in children with chronic kidney disease (CKD) and on kidney replacement therapy (KRT). Conversely, better growth in childhood CKD is associated with an improvement in several hard morbidity-mortality endpoints. Data from pediatric international registries has demonstrated that improvements in the overall conservative management of CKD, the search for optimal dialysis, and advances in immunosuppression and kidney transplant techniques have led to a significant improvement of final height over time. Infancy still remains a critical period for adequate linear growth, and the loss of stature during the first years of life influences final height. Preliminary new original data from the European Society for Paediatric Nephrology/European Renal Association-European Dialysis and Transplant Association (ESPN/ERA-EDTA) Registry confirm an association between the final height and the height attained at 2 years in children on KRT.

Hypertension in 172 Chinese Children: An 8-Year Retrospective Study

BACKGROUND

We evaluated children with hypertension and compared those with essential and secondary (including renal and non-renal) hypertension.

METHODS

This retrospective study analyzed data from hypertensive children (age, 0-18 years) referred for treatment between January 2008 and December 2015. Demographic factors, causative factors, and medical treatments were evaluated. Treatment failure was defined as a systolic or diastolic blood pressure ≥95th percentile for age, gender, and height on three separate occasions, despite treatment. All patients not meeting the failure criteria were considered to have controlled hypertension. The control rate was defined as the proportion of patients with controlled blood pressure.

RESULTS

Among 172 consecutive patients, 28% had essential hypertension and 72% had secondary hypertension. As compared with children with secondary hypertension, those with essential hypertension had a higher frequency of family history of hypertension (P<0.001), a higher body mass index (BMI) (P=0.001), lower frequency of proteinuria (P=0.003), lower uric acid (P=0.04), and lower triglyceride (P=0.048). The medications used in the controlled group were similar to those used in the uncontrolled group. Angiotensin-converting enzyme inhibitors (ACEIs) were only used in nephrogenic patients, and a higher rate of ACEI use seemed to increase control rates. Control rates did not significantly differ by age, number of drugs, or cause of hypertension.

CONCLUSIONS

As compared with children with secondary hypertension, those with essential hypertension were more likely to have a family history of hypertension and had a higher BMI, lower frequency of proteinuria, and lower uric acid and triglyceride concentrations. Treatment guidelines for essential and secondary hypertension should be established for children of all ages.

An Interdisciplinary Approach to Optimize the Care of Transitioning Adolescents and Young Adults with CKD

Adolescents and young adults (AYAs) with CKD or end-stage kidney disease (ESKD) have unique medical, dental, psychosocial, neurocognitive, and academic needs and require close interdisciplinary collaboration to optimize their care. The etiology of CKD in AYAs is diverse compared to older adults. With their continuously improved survival, AYAs must start preparation for health-care transition (HCT) from pediatric- to adult-focused health care in the pediatric setting and it must continue at the adult-focused setting, given that their brain maturation and self-management skill acquisition occur until their mid-20s. While the growth and physical maturation of most visible body parts occur before 18 years of age, the prefrontal cortex of the brain, where reasoning, impulse control, and other higher executive functions reside, matures around 25 years of age. The HCT process must be monitored using patient- and caregiver-measuring tools to guide interventions. The HCT process becomes more complex when patients and/or caregivers have a language barrier, different cultural beliefs, or lower literacy levels. In this article, we discuss the unique comorbidities of pediatric-onset CKD/ESKD, provide information for a planned HCT preparation, and suggest interdisciplinary coordination as well as cultural and literacy-appropriate activities to achieve optimal patient outcomes.

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.

Protein energy wasting; what is it and what can we do to prevent it?

Some children with declining height and BMI SDS fail to respond to optimisation of nutritional intake. As well as poor growth, they have muscle wasting and relative preservation of body fat. This is termed protein energy wasting (PEW). The process results from an interaction of chronic inflammation alongside poor nutritional intake. This review discusses the causes and potential preventative therapies for PEW.

Protein Energy Wasting in Children With Chronic Kidney Disease and End-Stage Kidney Disease: An Observational Study

OBJECTIVES

Protein energy wasting (PEW), a specific nutritional comorbidity associated with increased mortality, is underrecognized in children with chronic kidney disease (CKD). The aim of this study was to determine the burden and factors associated with PEW and assess the utility of parameters used to diagnose PEW in children with CKD and End stage kidney disease (ESKD).

METHODS

Children between 2 and 18 years of age with CKD stages 2-5 were recruited over 30 months. Parameters of PEW assessed included body mass index for height, mid-upper arm circumference, height for age, appetite, serum albumin, cholesterol, transferrin, and C-reactive protein. Based on number of criteria fulfilled in each subject, PEW was further stratified as mild, standard, and modified PEW.

RESULTS

One hundred twenty-three children (male:female 3:1, 73 in CKD stages 2-4, 50 with ESKD) were recruited. PEW was observed in 58% (47% in CKD stages 2-4 vs. 73% ESKD, P = .035). Longer duration and severity of disease was associated PEW. Reduced appetite (P = .001, P = .04), low mid-upper arm circumference (P = .000, P = .006), and low body mass index for height (P = .000, P = .007) were useful criteria to diagnose PEW in CKD stages 2-4 and ESKD, while most children did not meet biochemical criteria. Inflammation observed in 47% was higher in those with ESKD [CKD stages 2-4: 72 (39%) vs. ESKD: 29 (59%), P = .02] but was associated with PEW only in CKD stages 2-4.

CONCLUSION

PEW was highly prevalent in children with CKD and ESKD. Appetite and anthropometry measures were more useful than biochemical criteria for diagnosis of PEW. Whereas inflammation was common, it was associated with PEW only in CKD stages 2-4. Pediatric CKD and ESKD may need exclusive diagnostic criteria for PEW based on anthropometry, appetite, and inflammation.

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.

Urolithiasis, growth and blood pressure in childhood: A case-control study

BACKGROUND & AIMS

Kidney stone is a life-threatening disease with subsequent complications, especially in children who overtake this disease in early ages. This study assessed the effect of kidney stone history on current blood pressure and growth parameters of children.

METHODS

A two hundred children with (n = 100) and without (n = 100) a history of urolithiasis from Pediatric Urology clinics at the Aliasghar hospital, Tehran, Iran, participated in this case-control study. Several demographic data, height, weight, body mass index (BMI), BMI for age and blood pressure index were measured as the primary outcomes.

RESULTS

type of birth and infancy feeding, carbohydrate and energy intake were significantly different between the two groups (P = 0.008, 0.002, 0.03 and < 0.001 respectively). Ordinal logistic regression analysis showed that the current weight (P = 0.001) and BMI for age (P = 0.02) of the stone formers were lower than the non-stone formers, while no significant association found between the blood pressure or current height and the history of urolithiasis.

CONCLUSION

Our findings suggest that childhood urolithiasis has no significant effect on growth failure and blood pressure in childhood but it has a little impact on weight and BMI for age in older ages.

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.

Catch-up growth in children with chronic kidney disease started on enteral feeding after 2 years of age

BACKGROUND

Enteral feeding by tube in chronic kidney disease (CKD) before 2 years of age improves growth. Whether it is effective after this age is unknown. We assessed whether height and weight SDS changed after tube feeding was started in children with CKD above 2 years of age.

METHODS

Retrospective study of pre-transplant, pre-pubertal children (< 11 years) with CKD stages 2-5 started on nasogastric tube or gastrostomy feeds for the first time after age 2 years. Children were identified by searching dietetic records and the renal database. Children on growth hormone were excluded. Height, weight, and BMI were documented 1 year prior to and at the start of tube feeds, and after 1 and 2 years. Data collection ceased at transplantation.

RESULTS

Fifty children (25 male) were included. The median (range) age at start of tube feeds was 5.6 (2.1-10.9) years. Sixteen children were dialysed (1 haemodialysis, 15 peritoneal dialysis); 34 predialysis patients had a median (range) eGFR of 22 (6-88) ml/min/1.73 m². Overall height SDS (Ht SDS) improved from - 2.39 to - 2.27 at 1 year and - 2.18 after 2 years (p = 0.02). BMI SDS improved from - 0.72 to 0.23 after 1 year and was 0.09 after 2 years of enteral feeding (p < 0.0001). Height SDS improved more in children aged 2-6 years (- 2.13 to - 1.68, p = 0.03) and in children not on dialysis (- 2.33 to - 1.99, p = 0.002).

CONCLUSIONS

Enteral tube feeding commenced after 2 years of age in prepubertal children with CKD improves height and weight SDS, with stability of BMI during the second year. Younger children and those not on dialysis had the greatest benefit.

Serum albumin and hospitalization among pediatric patients with end-stage renal disease who started dialysis therapy

BACKGROUND

Hypoalbuminemia is a strong predictor of hospitalization and mortality among adult dialysis patients. However, data are scant on the association between serum albumin and hospitalization among children new to dialysis.

METHODS

In a retrospective cohort study of children 1-17 years old with end-stage renal disease receiving dialysis therapy in a large US dialysis organization 2007-2011, we examined the association of serum albumin with hospitalization frequency and total hospitalization days using a negative binomial regression model.

RESULTS

Among 416 eligible patients, median (interquartile range) age was 14 (10-16) years and mean ± SD baseline serum albumin level was 3.7 ± 0.8 g/dL. Two hundred sixty-six patients (64%) were hospitalized during follow-up with an incidence rate of 2.2 (95%CI, 1.9-2.4) admissions per patient-year. There was a U-shaped association between serum albumin and hospitalization frequency; hospitalization rates (95%CI) were 2.7 (2.2-3.2), 1.9 (1.5-2.4), 1.6 (1.3-1.9), and 2.7 (1.7-3.6) per patient-year among patients with serum albumin levels < 3.5, 3.5- < 4.0, 4.0- < 4.5, and ≥ 4.5 g/dL, respectively. Case mix-adjusted hospitalization incidence rate ratios (IRRs) (95%CI) were 1.63 (1.24-2.13), 1.32 (1.10-1.58), and 1.25 (1.06-1.49) at serum albumin levels 3.0, 3.5, and 4.5 g/dL, respectively (reference: 4.0 g/dL). Similar trends were observed in hospitalization days. These associations remained robust against further adjustment for laboratory variables associated with malnutrition and inflammation.

CONCLUSIONS

Both high and low serum albumin were associated with higher hospitalization in children starting dialysis. Because the observed association is novel and not fully explainable especially for high serum albumin levels, interpreting the results requires caution and further studies are needed to confirm and elucidate this association before clinical recommendations are made.

Chronic Kidney Disease: Treatment of Comorbidities I: (Nutrition, Growth, Neurocognitive Function, and Mineral Bone Disease)

PURPOSE OF REVIEW

This review discusses the complications of nutrition, growth, neurocognitive function and mineral and bone disorder in pediatric chronic kidney disease. We discuss the most recent evidence-based methods for evaluation and prevention of these complications in addition to treatment strategies to address the complications and mitigate adverse effects.

RECENT FINDINGS

Frequent nutritional assessment is important, particularly for infants and young children. Due to anorexia, oral aversion and dietary restrictions, weight gain may be difficult to achieve. Adequate nutrition is important for growth. Children with CKD tend to be short, which can impact quality of life and social achievements. Once nutrition is optimized, growth hormone is an effective, but underutilized strategy to improving terminal height. Mineral and bone disorder is a difficult but common complication of CKD which may present with and be driven by abnormalities in calcium, phosphorus and parathyroid hormone levels. Treatment strategies include dietary phosphorus restriction, phosphorus binders, and inactive vitamin D and active vitamin D sterols. Effective treatment may reduce the risk for bone deformities, growth abnormalities, fractures, cardiovascular disease and mortality. Children with CKD also suffer from cognitive difficulties. Control of anemia, aggressive childhood nutrition, and decreased exposure to heavy metals (via dialysate and dietary binding agents) has provided substantial improvement to the more profound neurocognitive sequelae observed prior to the 1990s. Current prevention of cognitive sequelae may best be directed at improved blood pressure control and augmented school support.

SUMMARY

Pediatric CKD has systemic ramifications and can impact all aspects of normal development, including nutrition, growth, bone and mineral metabolism and neurocognitive function. Regular evaluation for disease complications and prompt treatment can reduce the untoward effects of CKD thereby improving the quality and duration of life.

Clinical practice recommendations for growth hormone treatment in children with chronic kidney disease

Achieving normal growth is one of the most challenging problems in the management of children with chronic kidney disease (CKD). Treatment with recombinant human growth hormone (GH) promotes longitudinal growth and likely enables children with CKD and short stature to reach normal adult height. Here, members of the European Society for Paediatric Nephrology (ESPN) CKD–Mineral and Bone Disorder (MBD), Dialysis and Transplantation working groups present clinical practice recommendations for the use of GH in children with CKD on dialysis and after renal transplantation. These recommendations have been developed with input from an external advisory group of paediatric endocrinologists, paediatric nephrologists and patient representatives. We recommend that children with stage 3–5 CKD or on dialysis should be candidates for GH therapy if they have persistent growth failure, defined as a height below the third percentile for age and sex and a height velocity below the twenty-fifth percentile, once other potentially treatable risk factors for growth failure have been adequately addressed and provided the child has growth potential. In children who have received a kidney transplant and fulfil the above growth criteria, we recommend initiation of GH therapy 1 year after transplantation if spontaneous catch-up growth does not occur and steroid-free immunosuppression is not a feasible option. GH should be given at dosages of 0.045–0.05 mg/kg per day by daily subcutaneous injections until the patient has reached their final height or until renal transplantation. In addition to providing treatment recommendations, a cost-effectiveness analysis is provided that might help guide decision-making.

This Evidence-Based Guideline developed by members of the European Society for Paediatric Nephrology CKD-MBD, Dialysis and Transplantation working groups presents clinical practice recommendations for the use of growth hormone in children with chronic kidney disease on dialysis and after renal transplantation.

Short stature in advanced pediatric CKD is associated with faster time to reduced kidney function after transplant

BACKGROUND

Among children who receive a kidney transplant, short stature is associated with a more complicated post-transplant course and increased mortality. Short stature prior to transplant may reflect the accumulated risk of multiple factors during chronic kidney disease (CKD); however, its relationship with post-transplant kidney function has not been well characterized.

METHODS

In the Chronic Kidney Disease in Children (CKiD) cohort restricted to children who received a kidney transplant, short stature (i.e., growth failure) was defined as age-sex-specific height < 3rd percentile. The outcome was time to estimated glomerular filtration rate (eGFR) < 45 ml/min/1.73 m² after transplant. Parametric survival models, including adjustment for disease severity, socioeconomic status (SES), and parental height by inverse probability weighting, described the relative times to eGFR< 45 ml/min/1.73 m².

RESULTS

Of 138 children (median CKD duration at transplant: 13 years), 20% (28) had short stature before the transplant. The median time to eGFR < 45 ml/min/1.73 m² after kidney transplantation was 6.6 years and those with short stature had a significantly faster time to the poor outcome (log-rank p value 0.004). Children with short stature tended to have lower SES, nephrotic proteinuria, higher blood pressure, and lower mid-parental height before transplant. After adjusting for these variables, children with growth failure had 40% shorter time to eGFR < 45 ml/min/1.73 m² than those with normal stature (relative time 0.60, 95%CI 0.32, 1.03).

CONCLUSIONS

Short stature was associated with a faster time to low kidney function after transplant. SES, disease severity, and parental height partially explained the association. Clinicians should be aware of the implications of growth failure on the outcome of this unique population, while continued attempts are made to define modifiable factors that contribute to this association.

Development of a risk score for earlier diagnosis of chronic kidney disease in children

Objective

To develop a clinical score for the early identification of chronic kidney disease (CKD) in children and adolescents. The early diagnosis of CKD in childhood allows the adoption of measures to slow the progression of the disease, thereby reducing morbidity and mortality. Nevertheless, the diagnosis is often made too late for proper patient management.

Study design

We preformed a case-control study of a multicenter Brazilian sample of 752 pediatric patients; the study cases (n = 376) were CKD patients with a median estimated GFR of 37 (IQR = 22 to 57) ml/min/1.73 m². The control group (n = 376) comprised age-, gender- and center-matched children who were followed for nonrenal diseases. Potential risk factors were investigated through a standard questionnaire that included symptoms, medical history, and a clinical examination. Two multivariable models (A and B) were fitted to assess predictors of the diagnosis of CKD.

Results

In model A, 9 variables were associated with CKD diagnosis: antenatal ultrasound with urinary malformation, recurrent urinary tract infection, polyuria, abnormal urine stream, nocturia, growth curve flattening, history of hypertension, foamy urine and edema (c-statistic = 0.938). Model B had the same variables as model A, except for the addition of the history of admission during the neonatal period and the exclusion of antenatal ultrasound variables (c-statistic = 0.927).

Conclusions

The present scores may serve as a warning sign for CKD diagnosis in children among professionals working in the primary care setting where the symptoms associated with a risk of CKD may be overlooked.

Peptide nutrient-energy dense enteral feeding in critically ill infants: an observational study

BACKGROUND

Enteral feeding is challenging in critically ill infants. Target intakes are often not achieved as a result of fluid restriction, procedural interruptions and perceived enteral feeding intolerance. In those infants perceived to have poor feeding tolerance, the use of a peptide nutrient-energy dense enteral feed (PEF) may improve nutritional intake and minimise feeding interruptions as a result of gastrointestinal symptoms. The aim of this observational study was to characterise the use of a PEF amongst critically ill infants in two paediatric intensive care units (PICUs).

METHODS

Records from critically ill infants aged <12 months admitted to two PICUs were retrospectively reviewed with a PICU length of stay (LOS) ≥ 7 days. Achievement of nutritional targets for the duration of PEF was reviewed. Gastrointestinal symptoms, including gastric residual volume, constipation and vomiting, were evaluated as tolerance parameters.

RESULTS

In total, 53 infants were included, with a median age on admission of 2.6 months. Median admission weight was 3.9 kg in PICU-1 and 4.7 kg in PICU-2. Median (interquatile range) energy intake in PICU-1 and PICU-2 was 68 (47-92) and 90 (63-124) kcal kg^-1 , respectively, and median (interquatile range) protein intake 1.7 (1.1-2.4) g kg^-1 and 2.5 (1.6-3.2) g kg^-1 , respectively. Feeding was withheld because of feeding intolerance in one infant (4%) on two occasions in PICU-1 for 2.5 h and in two infants (7%) on two occasions in PICU-2 for 19.5 h. Gastric residual mean (SD) volumes were 3.5 (5.4) mL kg^-1 in PICU-1 and 16.9 (15.6) mL kg^-1 in PICU-2.

CONCLUSIONS

Peptide nutrient-energy dense feeding in infants admitted to the PICU is feasible, well tolerated and nutritional targets are met. However, with this study design, it is not possible to draw any conclusions regarding the benefit of PEF over standard PE feed in critically ill children and future work is required to clarify this further.

Estimated GFR at Dialysis Initiation and Mortality in Children and Adolescents

RATIONALE & OBJECTIVE

The association of estimated glomerular filtration rate (eGFR) at dialysis therapy initiation with mortality among adult dialysis patients has been greatly debated, with some studies showing no benefit from early dialysis therapy initiation. However, this association has not been well investigated in pediatric dialysis patients. The objective of this study was to evaluate the mortality risk associated with eGFR at dialysis therapy initiation in children and adolescents with kidney failure.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

9,963 incident dialysis patients aged 1 to 17 years in the US Renal Data System registry (1995-2016).

PREDICTOR

eGFRs at dialysis therapy initiation calculated using the pediatric-specific bedside Schwartz equation (<5, 5-<7, 7-<9, 9-<12, and ≥12mL/min/1.73m²).

OUTCOME

Time to all-cause death.

ANALYTICAL APPROACH

Cox proportional hazards regression adjusted for case-mix variables, height, body mass index, hemoglobin level, and serum albumin level.

RESULTS

Median eGFR was 7.8 (IQR, 5.6-10.5) mL/min/1.73m² and median age was 13 (IQR, 9-16) years. 696 deaths were observed during the median follow-up of 1.4 (IQR, 0.7-2.7) years, and overall crude mortality rate was 31 per 1,000 patient-years. There appeared to be a trend toward higher mortality risk across higher eGFRs at dialysis therapy initiation. Compared with eGFRs of 7 to <9mL/min/1.73m², eGFRs <5 and ≥12mL/min/1.73m² were associated with lower and higher mortality, with adjusted HRs of 0.57 (95% CI, 0.43-0.74) and 1.31 (95% CI, 1.05-1.65), respectively. In age-stratified analysis, there were consistent relationships among patients 6 years and older while the eGFR-mortality association was attenuated among patients younger than 6 years (P_interaction = 0.002).

LIMITATIONS

Possible errors in eGFRs due to methods for serum creatinine measurement. Unmeasured confounders related to eGFR at dialysis therapy initiation.

CONCLUSIONS

Higher eGFR at dialysis therapy initiation was associated with higher mortality risk. Further studies of eGFR at initiation are needed in pediatric dialysis patients, especially among those younger than 6 years.

Nutrition imbalance in Chinese chronic kidney disease children

BACKGROUND

Nutrition imbalance is common in chronic kidney disease (CKD) children. This study evaluated the nutrition status of CKD children at different stages using bioimpedance analysis (BIA) compared with anthropometry.

METHODS

Fifty-five CKD children at stages III, IV, V and 19 age- and sex-matched healthy controls were recruited. Fat, protein and mineral composition on BIA were analyzed together with anthropometry for height, weight and body mass index (BMI). Biochemistry was also checked in CKD children.

RESULTS

Of the CKD children, 23.6%, 10.9% and 56.3% were underweight, overweight/obese and stunted, respectively. On BIA, 52.7%, 70.9%, 14.5% and 40.0% of the CKD children had protein reduction, fat reduction, fat enhancement and mineral reduction, respectively. Growth retardation and nutrition reduction became remarkable at stages IV and V. Approximately 65% of healthy-weight children had nutrition reduction. In the underweight and healthy-weight groups, fat reduction rates were higher than protein reduction rate. In the overweight/obese group, fat enhancement was most notable. Mineral reduction was less remarkable.

CONCLUSIONS

The nutrition imbalance in CKD children on BIA correlated well with anthropometry and disease process, supporting BIA as an auxiliary diagnosis tool.

Let food be thy medicine and medicine be thy food?

Ensuring adequate nutrition in children with chronic kidney disease whilst avoiding hyperkalaemia can be a difficult balance to achieve. Pre-treatment of feeds, whether milk, formula or enteral nutrition, with sodium polystyrene sulfonate (SPS) is practiced in some paediatric centres internationally. Such treatments are purported to avoid the potentially serious complications of direct administration of SPS, such as intestinal necrosis, aspiration pneumonitis and metabolic alkalosis to name but a few. Although described some 45 years ago, this study by Palma et al. is only the second retrospective study to describe the clinical consequence of pre-treating feeds with SPS with the majority of earlier studies describing only the in vitro effects of this method. Whilst effective in reducing serum potassium, the authors justifiably highlight the high incidence of complications, such as hypokalaemia (31.6%) and hypernatraemia (26.3%). We have further highlighted this with a summary of the available literature on this subject demonstrating the gross alterations of the electrolyte composition of feeds following SPS pre-treatment and clinical complications in its application. We heartily agree and support the conclusion by Palma et al. that where this therapy is practiced, close monitoring of electrolytes is essential and much more work is needed to identify those patient cohorts for which this can indeed be considered a safe and effective intervention.

Cachexia in children with chronic kidney disease: challenges in diagnosis and treatment

PURPOSE OF REVIEW

Although cachexia is highly prevalent in adult patients with chronic kidney disease (CKD), it is understudied and less well characterized in children. Recent evidence suggests that cachexia is also prevalent in children with CKD but presents challenges in diagnosis and treatment.

RECENT FINDINGS

A study from the CKD in children cohort showed that CKD cachexia or protein-energy wasting, using modified pediatric diagnostic criteria, such as lack of expected weight gain instead of weight loss and BMI for height age, had a prevalence of 7-20%. When growth indices such as height SD score (SDS)/height velocity SDS was included in the criteria, cachexia or PEW correlated with the morbidity outcome of increased hospitalization risk in children with CKD. Conversely, aggressive nutritional supplementation in children with advanced CKD, with nasogastric or gastric tube feeding, led to prevalence of obesity over that of cachexia. Body habitus of underweight and obesity have been shown to be associated with the worst clinical outcomes in both adults and children with CKD.

SUMMARY

Optimal nutritional therapy remains the mainstay of treatment of cachexia in CKD children with therapeutic goals of maintaining BMI as well as linear growth within the normal range.

Growth and Nutrition in Pediatric Chronic Kidney Disease

Children with chronic kidney disease (CKD) feature significant challenges to the maintenance of adequate nutrition and linear growth. Moreover, the impaired nutritional state contributes directly to poor growth. Therefore, it is necessary to consider nutritional status in the assessment of etiology and treatment of sub-optimal linear growth. The major causes of poor linear growth including dysregulation of the growth hormone/insulin-like growth factor-I (IGF-I) axis, nutritional deficiency, metabolic acidosis, anemia, renal osteodystrophy/bone mineral disease, and inflammation. This review summarizes the causes and assessment tools of growth and nutrition while providing a summary of state of the art therapies for these co-morbidities of pediatric CKD.

Effect of renal function on antihypertensive drug safety and efficacy in children

BACKGROUND

Hypertension and chronic kidney disease (CKD) are common comorbidities. Guidelines recommend treating hypertension in children with CKD because it is a modifiable risk factor for subsequent cardiovascular disease. Children with CKD are frequently excluded from antihypertensive drug trials. Consequently, safety and efficacy data for antihypertensive drugs are lacking in children with CKD.

METHODS

We determined the incidence of adverse events in 10 pediatric antihypertensive trials to determine the effect of renal function on antihypertensive safety and efficacy in children. These trials were submitted to the US Food and Drug Administration from 1998 to 2005. We determined the number and type of adverse events reported during the trials and compared these numbers in participants with normal renal function and those with decreased function (defined as an estimated glomerular filtration rate [eGFR] <90 mL/min/1.73 m2 calculated using the original Schwartz equation).

RESULTS

Among the 1,703 children in the 10 studies, 315 had decreased renal function. We observed no difference between the two cohorts in the incidence of adverse events or adverse drug reactions related to study drug. Only 5 participants, all with decreased renal function, experienced a serious adverse event; none was recorded by investigators to be study drug-related. Among treated participants, children with decreased renal function who received a high dose of study drug had a significantly larger drop in diastolic blood pressure compared with children with normal renal function.

CONCLUSIONS

These data show that antihypertensive treatment in children with renal dysfunction can be safe and efficacious, and consideration should be given to their inclusion in selected drug development programs.

Hypertension in pediatric patients with chronic kidney disease: management challenges

In contrast to adults where hypertension is a leading cause of chronic kidney disease, in pediatrics, hypertension is predominantly a sequela, however, an important one that, like in adults, is likely associated with a more rapid decline in kidney function or progression of chronic kidney disease to end stage. There is a significant issue with unrecognized, or masked, hypertension in childhood chronic kidney disease. Recent evidence and, therefore, guidelines now suggest targeting a blood pressure of <50th percentile for age, sex, and height in children with proteinuria and chronic kidney disease. This often cannot be achieved by monotherapy and additional agents need to be added. Blockade of the renin angiotensin aldosterone system represents the mainstay of therapy, although often limited by the side effect of hyperkalemia. The addition of a diuretic, at least in the earlier stages of chronic kidney disease, might help mitigate this problem.

[Somatotropic axis and molecular markers of mineral metabolism in children undergoing chronic peritoneal dialysis]

Growth failure is one of the most relevant complications in children with chronic kidney disease (CKD). Among others, growth hormone (GH) resistance and bone mineral disorders have been identified as the most important causes of growth retardation.

OBJECTIVES

1. To characterize bone mineral metabolism and growth hormone bio-markers in CKD children treated with chronic peritoneal dialysis (PD). 2. To evaluate height change with rhGH treatment.

PATIENTS AND METHOD

A longitudinal 12-month follow-up in prepuberal PD children.

EXCLUSION CRITERIA

Tanner stage >1, nephrotic syndrome, genetic disorders, steroids, intestinal absorption disorders, endocrine disturbances, treatment with GH to the entry of the study. Demographic and anthropometric data were registered. FGF23, Klotho, VitD, IGF-1, IGFBP3, and GHBP were measured to evaluate mineral and growth metabolism.

RESULTS

15 patients, 7 male, age 6.9 ± 3.0 y were included. Time on PD was 14.33 ± 12.26 months. Height/age Z score at month 1 was -1.69 ± 1.03. FGF23 and Klotho: 131.7 ± 279.4 y 125.9 ± 24.2 pg/ml, respectively. 8 patients were treated with GH during 6-12 months, showing a non-significant increase in height/age Z-score during the treatment period. Bivariate analysis showed a positive correlation between Klotho and delta ZT/E, and between GHBP vs growth velocity index (p < .05).

CONCLUSIONS

FGF23 values were high and Klotho values were reduced in children with CKD in PD, comparing to healthy children. Somatotropic axis variables were normal or elevated. rhGH tends to improve height and there is a positive correlation of GHBP and growth velocity in these children.

Assessment of dietary intake of children with chronic kidney disease

OBJECTIVE

Our aim was to characterize the nutrient intake of children with chronic kidney disease (CKD) relative to recommended intake levels.

METHODS

We conducted a cross-sectional study of dietary intake assessed by Food Frequency Questionnaire (FFQ) in The North American Chronic Kidney Disease in Children (CKiD) prospective cohort study. Nutrient intake was analyzed to estimate the daily consumption levels of various nutrients and compared with national guidelines for intake.

RESULTS

There were 658 FFQs available for analysis; 69.9 % of respondents were boys, with a median age [Interquartile range (IQR)] of 11 years (8-15). Median daily sodium, potassium, and phosphorus intake was 3089 mg (2294-4243), 2384 mg (1804-3076), and 1206 mg (894-1612) respectively. Sodium and phosphorus consumptions were higher than recommended in all age groups. Caloric intake decreased with dropping glomerular filtration rate (GFR) (p = 0.003). The median daily caloric intakes were 1307 kcal in male children 2-3 years old, 1875 kcal in children 4-8 years old, 1923 kcal in those 9-13 years old, and 2427 kcal in those 14-18 years old. Respective levels for girls were 1467 kcal, 1736 kcal, 1803 kcal, and 2281 kcal. Median protein intake exceeded recommended levels in all age groups, particularly among younger participants. Younger children were more likely than older children to exceed the recommended intakes for phosphorus (p < 0.001) and the age-specific recommended caloric intake (p < 0.001). Macronutrient distribution (carbohydrate:fat:protein) was consistent with recommendation.

CONCLUSIONS

Children in the CKiD cohort consumed more sodium, phosphorus, protein, and calories than recommended. The gap between actual consumption and recommendations indicates a need for improved nutritional counseling and monitoring.

Health-related quality of life in patients with pediatric onset of end-stage renal disease: state of the art and recommendations for clinical practice

Health-related quality of life (HRQoL) is increasingly recognized as a key outcome in both clinical and research settings in the pediatric population with end-stage renal disease (ESRD). This review aims to: (1) summarize the current knowledge on HRQoL and socioprofessional outcomes and (2) provide strategies for incorporation of HRQoL assessment into clinical practice. Studies report that pediatric patients with ESRD have significantly lower HRQoL scores compared with children with other chronic diseases. Patients treated by dialysis are at particularly high risk for impaired HRQoL. Furthermore, patients more often have impaired neurocognitive functioning and lower academic achievement. Important determinants of impaired HRQoL include medical factors (i.e., receiving dialysis, disabling comorbidities, cosmetic side effects, stunted growth), sociodemographic factors (i.e., female gender, non-Western background) and psychosocial factors (i.e., noneffective coping strategies). Contrary to the situation in childhood, adult survivors of pediatric ESRD report a normal mental HRQoL. Despite this subjective feeling of well-being, these patients have on average experienced significantly more difficulties in completing their education, developing intimate relationships, and securing employment. Several medical and psychosocial strategies may potentially improve HRQoL in children with ESRD. Regular assessment of HRQoL and neurocognitive functioning in order to identify areas in which therapies and interventions may be required should be part of standard clinical care.

Growth hormone therapy in children with CKD after more than two decades of practice

This review focuses on the evidence for the efficacy and safety of recombinant human growth hormone (rhGH) therapy in children with all stages of chronic kidney disease (CKD) and at all ages. It describes the improving height prognosis for our patients both with and without rhGH; explains the underlying hormonal abnormalities that provide the rationale for rhGH use in CKD and the endocrine changes that accompany treatment; and views on who warrants treatment, with what dose, and how long for.

Chronic kidney disease in children

Chronic kidney disease (CKD) is a major health problem worldwide. Although relatively uncommon in children, it can be a devastating illness with many long-term consequences. CKD presents unique features in childhood and may be considered, at least in part, as a stand-alone nosologic entity. Moreover, some typical features of paediatric CKD, such as the disease aetiology or cardiovascular complications, will not only influence the child's health, but also have long-term impact on the life of the adult that they will become. In this review we will focus on the unique issues of paediatric CKD, in terms of aetiology, clinical features and treatment. In addition, we will discuss factors related to CKD that start during childhood and require appropriate treatments in order to optimize health outcomes and transition to nephrologist management in adult life.

Growth and nutritional status in children with chronic kidney disease on maintenance dialysis in Poland

PURPOSE

Despite vast availability of modern methods of treatment of chronic kidney disease and its complications, the short stature still is a major point of concern in adolescents with chronic kidney disease. The aim of the study was to assess changes in growth and nutritional status of Polish children on renal replacement therapy in the decade, 2004-2013.

MATERIAL AND METHODS

The study was designed as a cross-sectional analysis of anthropometric values and selected indices of growth status amongst children receiving dialysis in Poland between the years 2004 and 2013. Data were acquired during two different multicentre studies on hypertension in dialyzed children in Poland. Basic anthropometric parameters (body weight, body height/length, body mass index - BMI), dialysis adequacy and duration of RRT were assessed.

RESULTS

The study showed that anthropometric parameters of children undergoing renal replacement therapy had not significantly changed in the last 10 years of observation. Children on RRT were still of short stature despite availability of modern methods of hormonal therapy and nutrition. Median of height z-score was -2.10 in 2004 and -2.19 in 2013. Expected clinical improvement in these measures was not proven.

CONCLUSIONS

The cause of chronic kidney disease, method of dialysis, time on dialysis or dialysis adequacy did not influence the anthropometric parameters significantly in dialyzed children in Poland.

Infectious outcomes following gastrostomy in children receiving peritoneal dialysis

BACKGROUND

Early institution of enteral feeding in paediatric end-stage kidney disease (ESKD) is recommended. For patients on peritoneal dialysis (PD) there is concern that gastrostomy tube (GT) insertion may be complicated by increased peritonitis, in particular fungal. Our unit favours early planned GT insertion, and for those with late presentation, there is prompt consideration of GT insertion following dialysis initiation. This study evaluates our rates of peritonitis with GT insertion following or concurrent with PD initiation.

METHODS

This was a retrospective, single-centre, cross-sectional study of of 17 New Zealand children with ESKD who received PD in the period 2000-2011. Inclusion criteria were GT placement while on PD or initiation of PD within 72 h of GT insertion.

RESULTS

There were no cases of fungal peritonitis among the 17 children; however, two cases of early peritonitis with organisms derived from the gastrointestinal tract were identified. No statistically significant difference was found between incident rates of bacterial peritonitis before GT placement (0.6 episodes per patient-year; 95% confidence interval (CI) 0.26-1.18) and post-GT placement (1.21 episodes per patient-year; 95% CI 0.69-1.97).

CONCLUSION

Fungal peritonitis has never been encountered by out unit during its many years of experience in GT placement in patients without advanced malnutrition. When children on PD have insufficient dietary intake to maintain appropriate growth velocity, enteral feeding should be initiated promptly. A GT is considered to be safe for long-term use in selected patients.

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.

Medication adherence and growth in children with CKD

BACKGROUND AND OBJECTIVES

Poor growth is a consequence of CKD, but can often be partially or fully prevented or corrected with the use of a number of medications. The extent of nonadherence with medications used to treat or mitigate growth failure in CKD has not been examined prospectively in children with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The prevalence of both prescription of and nonadherence to recombinant human growth hormone (rhGH), phosphate binders, alkali, active vitamin D, nutritional vitamin D, iron, and erythrocyte-stimulating agents was summarized over the first seven visits of the Chronic Kidney Disease in Children cohort study. The association between self-reported nonadherence to each medication group and the mean annual change in age- and sex-specific height z score was quantified using seven separate linear regression models with generalized estimating equations.

RESULTS

Of 834 participants, 597 reported use of at least one of these medication groups and had adherence data available. Nonadherence ranged from 4% over all visits for erythrocyte-stimulating agents to 22% over all visits for nutritional vitamin D. Of the study participants, 451 contributed data to at least one of the analyses of adherence and changes in height z score. Children nonadherent to rhGH had no change in height z score, whereas those adherent to rhGH had a significant improvement of 0.16 SDs (95% confidence interval, 0.05 to 0.27); the effect size was slightly larger and remained significant after adjustment. Among participants with height≤3rd percentile and after adjustment, adherence to rhGH was associated with a 0.33 SD (95% confidence interval, 0.10 to 0.56) greater change in height z score. Nonadherence with other medication groups was not significantly associated with a change in height z score.

CONCLUSIONS

Self-reported nonadherence to rhGH was associated with poorer growth velocity in children with CKD, suggesting an opportunity for intervention and improved patient outcome.

Growth in children with chronic kidney disease: role of nutrition, growth hormone, dialysis, and steroids

PURPOSE OF REVIEW

Children with chronic kidney disease (CKD) have impaired growth that leads to short stature in adulthood. The problem persists even with successful transplantation and steroid withdrawal protocols. The aim of this review is to provide an overview of the pressing issues related to growth failure in children with CKD both before and after transplantation.

RECENT FINDINGS

Although great strides have been made in dialysis and transplantation, the incidence of abnormal adult height in children growing up with CKD remains as high as 45-60%. The lack of catch-up growth and resultant short stature is a critical issue for self-esteem and quality of life in many children with CKD. Aggressive daily dialysis, improved nutrition, treatment of metabolic bone disease, and the use of recombinant human growth hormone provide some hope for catch-up growth in select patients.

SUMMARY

The causes of growth failure in the setting of CKD are multifactorial. Attention to all the details by optimizing nutritional, bone and mineral metabolism, correcting metabolic acidosis and anemia, achieving excellent blood pressure control, reversing cardiovascular complications such as left ventricular hypertrophy, and minimizing the use of corticosteroids is the current standard of care. Aggressive daily dialysis can reverse many of the uremic derangements. For patients not yet on dialysis or for those after renal transplant, early institution of recombinant human growth hormone can promote growth. Improved understanding of the mechanisms of hormone resistance may offer novel targets or measurements of treatment effectiveness.

Growth of children with end-stage renal disease undergoing daily hemodialysis

BACKGROUND

The aim of this report is to describe the effect of daily hemodialysis on the growth of children with end-stage renal disease (ESRD).

METHODS

We performed a prospective, observational study on 24 children with ESRD undergoing daily hemodialysis (DHD). The control group comprised 26 children on concurrent conventional hemodialysis (CHD), and the follow-up for both groups was 9.3 ± 3.0 months. No patient received growth hormone (GH) therapy.

RESULTS

At the onset of the study, the height-for-age Z-score was -2.12 ± 1.54 in the CHD group and -2.84 ± 2.27 in the DHD group (p = 0.313). Assuming an increase of 0.5 standard deviation scores (SDS) of the height-for-age parameter as an improvement of growth, there were 33 % of patients in the DHD group and 8 % in the CHD group (p = 0.035). The cumulative probability of gain in height for age at 12 months was 40 % in the DHD group versus 15 % in the CHD group (p = 0.047). Also, 98 % of patients in the DHD group had an adequate total caloric intake, whereas 38 % in the CHD group reached this goal (p < 0.001). No patient left the study due to intensification of the dialysis modality.

CONCLUSIONS

Our data show that the DHD favored a 0.5 SDS height gain in a third of patients without GH treatment. Dialysis intensification was not a cause for treatment dropouts, and DHD should be considered as a treatment for selected cases, especially small children.