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

Advances and potential of regenerative medicine in pediatric nephrology

The endogenous capacity of the kidney to repair is limited, and generation of new nephrons after injury for adequate function recovery remains a need. Discovery of factors that promote the endogenous regenerative capacity of the injured kidney or generation of transplantable kidney tissue represent promising therapeutic strategies. While several encouraging results are obtained after administration of stem or progenitor cells, stem cell secretome, or extracellular vesicles in experimental kidney injury models, very little data exist in the clinical setting to make conclusions about their efficacy. In this review, we provide an overview of the cutting-edge knowledge on kidney regeneration, including pre-clinical methodologies used to elucidate regenerative pathways and describe the perspectives of regenerative medicine for kidney patients.

Children Are Not Small Adults: Similarities and Differences in Renal Transplantation Between Adults and Pediatrics

Kidney transplantation is the treatment of choice for all patients with end-stage kidney disease, including pediatric patients. Graft survival in pediatrics was lagging behind adults, but now is comparable with the adult cohort. Although many of the protocols have been adopted from adults, there are issues unique to pediatrics that one should be aware of to take care of this population. These issues include recipient size consideration, increased incidence of viral infections, problems related to growth, common occurrence of underlying urological issues, and psychosocial issues. This article addresses the similarities and differences in renal transplantation, from preparing a patient for transplant, the transplant process, to post-transplant complications.

Protein Biomarkers in Chronic Kidney Disease in Children-What Do We Know So Far?

Chronic kidney disease (CKD) in children is a major concern of medical care and public health as it is related to high morbidity and mortality due to progression to end-stage kidney disease (ESKD). It is essential to identify patients with a risk of developing CKD to implement therapeutic interventions. Unfortunately, conventional markers of CKD, such as serum creatinine, glomerular filtration rate (GFR) and proteinuria, have many limitations in serving as an early and specific diagnostic tool for this condition. Despite the above, they are still the most frequently utilized as we do not have better. Studies from the last decade identified multiple CKD blood and urine protein biomarkers but mostly assessed the adult population. This article outlines some recent achievements and new perspectives in finding a set of protein biomarkers that might improve our ability to prognose CKD progression in children, monitor the response to treatment, or even become a potential therapeutic target.

Psychological aspects in children and parents of children with chronic kidney disease and their families

Pediatric chronic kidney disease (CKD) is a chronic illness that affects the overall quality of life of patients during childhood. This article highlights the psychological and social burden of CKD in patients and their families. Patients with CKD and their families require comprehensive treatment for psychosocial problems. Therefore, it is crucial for pediatricians to screen for these issues and refer patients and their families for therapy. Tools that are short, easy to administer, and easy to score, such as the Pediatric Quality of Life Inventory or the Childhood Depression Inventory, can be utilized during routine clinical appointments. Reducing the negative impact of CKD on the family will improve the well-being and coping skills of patients and their families.

Evaluation of Pupils' Knowledge about Kidney Health

The purpose of this study was to investigate the level of renal function knowledge of primary school pupils in Greece. We conducted a cross-sectional study with a convenience sample of 220 pupils, coming from the 5th and 6th grades of general education schools. A questionnaire consisting of 11 questions was developed from scratch. However, based on an analysis of Cronbach's alpha values obtained when individual questions were deleted, two questions were removed from the analysis, and only nine remained for analysis and participated in the calculation of the knowledge score. Moreover, the gender and daily habits of pupils regarding water consumption and frequency of urination were recorded. Pupils had a high percentage of correct knowledge about the number of kidneys (95.2%), whether a child may have problems with the kidneys (85.5%) and whether a person can survive with one kidney (68.5%). Low levels of knowledge were observed in the function and role of the kidneys (36.4%), as well as the part of the body where the kidneys are located (30.9%). The median (interquartile range (IQR)) total knowledge score was 6 (5-7), with no difference detected between genders (p = 0.135). A statistically significant difference between pupils of 5th and 6th grades was found but the difference did not seem to be clinically significant (p = 0.035). The present research demonstrates that pupils' knowledge of renal function and the protection of their kidneys needs improvement.

Plasma and Urine Biomarkers of CKD: A Review of Findings in the CKiD Study

Serum creatinine and level of proteinuria, as biomarkers of chronic kidney disease (CKD) progression, inadequately explain the variability of glomerular filtration rate decline, and are late markers of glomerular filtration rate decline. Recent studies have identified plasma and urine biomarkers at higher levels in children with CKD and also associate independently with CKD progression, even after adjustment for serum creatinine and proteinuria. These novel biomarkers represent diverse biologic pathways of tubular injury, tubular dysfunction, inflammation, and tubular health, and can be used as a liquid biopsy to better characterize CKD in children. In this review, we highlight the biomarker findings from the Chronic Kidney Disease in Children cohort, a large longitudinal study of children with CKD, and compare results with those from other pediatric CKD cohorts. The biomarkers in focus in this review include plasma kidney injury molecule-1, monocyte chemoattractant protein-1, fibroblast growth factor-23, tumor necrosis factor receptor-1, tumor necrosis factor receptor-2, soluble urokinase plasminogen activator receptor, and chitinase-3-like protein 1, as well as urine epidermal growth factor, α-1 microglobulin, kidney injury molecule-1, monocyte chemoattractant protein-1, and chitinase-3-like protein 1. Blood and urine biomarkers improve our ability to prognosticate CKD progression and may improve our understanding of CKD pathophysiology. Further research is required to establish how these biomarkers can be used in the clinical setting to improve the clinical management of CKD.

Children on chronic hemodialysis before the first year of age in Brazil: A 3-year survival analysis

INTRODUCTION

The limited data on survival rates of small children undergoing hemodialysis preclude comparison with other countries. The goal of this study was to determine the mortality rate and its risk factors in children starting hemodialysis during their first year of life.

METHODS

We performed a retrospective cohort study, based on data from a reference dialysis center in São Paulo city. Data from 47 (8 females) children who underwent chronic hemodialysis before the first year of age were analyzed. Survival was characterized using Kaplan-Meier methods and log-rank tests, followed by a multivariable Cox regression model.

RESULTS

The survival rates were 93%, 75%, and 64% at 1, 2, and 3 years, respectively. Only cardiovascular comorbidity was significantly associated with the mortality outcome (HR = 5.7, 95% CI = 1.7-19.6, p = 0.006).

CONCLUSION

The survival rate among children who started hemodialysis in their first year of life was reasonable, similar to international standards.

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.

Neurological Complications and Associated Risk Factors in Children Affected with Chronic Kidney Disease

To investigate the correlation between chronic kidney disease (CKD) and the development of neurological disease among pediatric patients in Saudi Arabia. The present retrospective study recruited patients admitted to King Abdulaziz University Hospital during 2018. We reviewed electronic records to collect data on essential demographics including age, gender, and nationality; history of prior CNS disease or related symptoms; results of neurological physical examination; and findings of radiological investigations such as abdominal ultrasound, dimercaptosuccinic acid scan, micturating cystourethrogram, diethylene triamine pentaacetic acid scan, brain computed tomography, and magnetic resonance imaging. The most commonly diagnosed renal pathologies were neurogenic bladder and cystic kidney disease. The most common neurological manifestation was seizure disorder. Males were more frequently affected with neurological sequelae than females. The prevalence of neurological disorders was higher in patients over two years old. The most frequently observed stage of chronic kidney disease was stage 5. Most children who were affected with a neurological disorder required hemodialysis as part of their management plan. Patients with chronic kidney disease are at a high risk of neurocognitive defects. The type of management and renal diagnosis are significant factors that should be considered when anticipating central nervous system involvement in the case of chronic kidney disease.

Sex and Glomerular Filtration Rate Trajectories in Children

BACKGROUND AND OBJECTIVES

Differences in CKD progression by sex have been hypothesized to explain disparities in access to kidney transplantation in children. This study aims to identify distinct trajectories of eGFR decline and to investigate the association of sex with eGFR decline.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We used data from the CKD in Children study. Latent class mixed models were used to identify eGFR trajectories and patient characteristics were compared between trajectories. Progression was studied to two outcomes: ESKD (dialysis or transplantation) and a combined outcome of ESKD or 50% eGFR decline from baseline, using multivariable parametric failure time models.

RESULTS

Among 888 patients, 613 with nonglomerular and 275 with glomerular diseases, we observed four and two distinct GFR trajectories, respectively. Among patients with nonglomerular diseases, there was a higher proportion of males in the group with a low baseline GFR. This group had an increased risk of ESKD or 50% GFR decline, despite a similar absolute decline in GFR. Eight patients with nonglomerular diseases, mostly males with obstructive uropathies, had a more rapid absolute GFR decline. However, the association between male sex and rapid absolute GFR decline was NS after adjustment for age, baseline GFR, and proteinuria. Among patients with glomerular diseases, a subgroup including mostly females with systemic immunologic diseases or crescentic GN had a rapid absolute GFR decline.

CONCLUSIONS

This study identifies different trajectories of CKD progression in children and found a faster progression of CKD in females in patients with glomerular diseases, but no significant sex difference in patients with nonglomerular diseases. The differences in progression seem likely explained by sex differences in the underlying primary kidney disease and in baseline GFR rather than by a direct effect of sex on progression.

Concentrations of representative uraemic toxins in a healthy versus non-dialysis chronic kidney disease paediatric population

Background

Chronic kidney disease (CKD) in childhood is poorly explained by routine markers (e.g. urea and creatinine) and is better depicted in adults by other uraemic toxins. This study describes concentrations of representative uraemic toxins in non-dialysis CKD versus healthy children.

Methods

In 50 healthy children and 57 children with CKD Stages 1-5 [median estimated glomerular filtration rate 48 (25th-75th percentile 24-71) mL/min/1.73 m2; none on dialysis], serum concentrations of small solutes [symmetric and asymmetric dimethyl-arginine (SDMA and ADMA, respectively)], middle molecules [β2-microglobuline (β2M), complement factor D (CfD)] and protein-bound solutes [p-cresylglucuronide (pCG), hippuric acid (HA), indole-acetic acid (IAA), indoxyl sulphate (IxS), p-cresyl sulphate (pCS) and 3-carboxy-4-methyl-5-propyl-furanpropionic acid (CMPF)] were measured. Concentrations in the CKD group were expressed as z-score relative to controls and matched for age and gender.

Results

SDMA, CfD, β2M, IxS, pCS, IAA, CMPF and HA concentrations were higher in the overall CKD group compared with controls, ranging from 1.7 standard deviations (SD) for IAA and HA to 11.1 SD for SDMA. SDMA, CfD, β2M, IxS and CMPF in CKD Stages 1-2 with concentrations 4.8, 2.8, 4.5, 1.9 and 1.6 SD higher, respectively. In contrast, pCS, pCG and IAA concentrations were only higher than controls from CKD Stages 3-4 onwards, but only in CKD Stage 5 for ADMA and HA (z-score 2.6 and 20.2, respectively).

Conclusions

This is the first study to establish reference values for a wide range of uraemic toxins in non-dialysis CKD and healthy children. We observed an accumulation of multiple uraemic toxins, each with a particular retention profile according to the different CKD stages.

Association of nutritional status and health-related quality of life in children with chronic kidney disease

PURPOSE

Health-related quality of life (HRQoL) is an important, patient-centred measure. Although nutritional status is altered in children with CKD, the impact of nutritional status on HRQoL in this population has not been explored. The aims of this study are to report the HRQoL scores as assessed by the validated PedsQL™ questionnaire and to explore the relationship of HRQoL scores to markers of nutritional status. It will also examine the concordance between the scores of the child and their parent/carer.

METHODS

A single-centre, cross-sectional, observational study was performed exploring the markers of nutritional status (anthropometry-including presence of obesity, micronutrient status and appetite) and HRQoL and assessed by the PedsQL™ questionnaire in children aged 3-18 years with pre-dialysis, conservatively managed CKD.

RESULTS

A total of 46 children were recruited, with a mean age of 10.5 years. HRQoL scores were lower than in healthy controls throughout all domains. Lower scores were associated with short stature and poor appetite. Markers of obesity or micronutrient status were not associated with HRQoL scores.

DISCUSSION

Nutritional status impacts upon HRQoL. Further study is needed to evaluate how changing nutritional status may affect HRQoL in children with CKD, and this may be used to facilitate the development of patient-centred treatment goals and plans.

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.

Management of Denys-Drash syndrome: A case series based on an international survey

Denys-Drash syndrome (DDS), a condition caused by mutations in the tumor-suppressor gene WT-1, is associated with a triad of disorders: ambiguous genitalia, nephrotic syndrome leading to end-stage renal disease (ESRD), and Wilms’ tumor. Given the variable disease course, management is challenging. We aimed to describe the evolution of DDS and the range of management strategies by summarizing the clinical courses of cases collected from a questionnaire sent to the international pediatric nephrology community. 15 respondents provided information on 23 patients; 21 DDS cases were confirmed and analyzed. At DDS diagnosis, 6 patients had a Wilms’ tumor (group A) and 15 had no Wilms’ tumor (group B). Three group A patients had unilateral nephrectomy. Two of these still had renal function, with no second tumor, at 36 months and 16 years of age, and 1 progressed to ESRD. Three had bilateral nephrectomy before ESRD. Eight group B patients progressed to ESRD, all of whom later had all renal tissue removed. Two group B patients subsequently developed a unilateral Wilms’ tumor and had bilateral nephrectomy pre-ESRD. Three had bilateral nephrectomy prior to reaching ESRD without ever having a Wilms’ tumor. Two group B patients remained tumor-free with renal function at last follow-up. Two main management approaches were taken: pre-emptive nephrectomy prior to ESRD and conservative surveillance. Based on the known risks associated with ESRD in infants and young children, the variable course of DDS, and the relatively good prognosis associated with Wilms’ tumor, a guiding principle of preservation of renal function is most logical. Most would advocate bilateral prophylactic nephrectomy after ESRD is reached due to the high tumor risk, which is likely heightened after transplant.

Impact of next generation sequencing on our understanding of CAKUT

Congenital abnormalities of the kidney and urinary tract (CAKUT) form the leading cause of pediatric end-stage renal disease. Knowledge on the molecular mechanisms that underlie CAKUT leads to the improvement of DNA diagnostics and counseling regarding prognosis and recurrence risk estimation for CAKUT patients and their relatives. Implementation of next generation sequencing in research and diagnostic settings has led to the identification of the molecular basis of many developmental diseases. In this review, we summarize the efforts on next generation sequencing in CAKUT research and we discuss how next generation sequencing added to our understanding of CAKUT genetics. Although next generation sequencing has certainly proven to be a game changer in the field of disease gene identification and novel CAKUT-causing gene variants have been identified, most CAKUT cases still remain unsolved. Occurring with genetic and phenotypic heterogeneity along with incomplete penetrance, the identification of CAKUT etiology poses many challenges. We see great potential for combined -omics approaches that include next generation sequencing in the identification of CAKUT-specific biomarkers, which is necessary to optimize the care for CAKUT patients.

Adolescent nephrology: An emerging frontier for kidney care in sub-Saharan Africa

Adolescents make up a quarter of the world's population and are important users of health services. In South Africa little is known about the extent of renal disease or outcomes in this group. Adolescents are a vulnerable age group, due to their neurocognitive development, engagement in high-risk social activities, prevalence of mental illness and increasing rates of HIV infection. In Africa access to renal replacement therapy is rationed, therefore the focus of renal disease must be one of prevention rather than dealing with the management of end stage renal disease. Treating adolescents is a challenging field, as compliance is essential as a preventative strategy. This review will outline how a cost effective adolescent service was established in a resource limited setting. The adolescent friendly clinic aims to ease transition of adolescents, improve engagement within the health service and ultimately aims to improve compliance. In order to treat adolescents, it is important to deliver age-appropriate treatment that can be implemented in any chronic disease setting to give the adolescent the greatest chance of success.

Risk Factors for Neurocognitive Functioning in Children with Autosomal Recessive Polycystic Kidney Disease

This mini review provides an overview of the issues and challenges inherent in autosomal recessive polycystic kidney disease (ARPKD), with a particular focus on the neurological factors and neurocognitive functioning of this population. ARPKD typically is discovered at the end of pregnancy or during the neonatal developmental period and occurs in approximately 1 in 20,000 live births. During the neonatal period, there is a relatively high risk of death, with many infants dying from respiratory failure. As the child ages, they experience progressive kidney disease and become increasingly vulnerable to liver disease, with many individuals eventually requiring dual organ transplants. This mini review provides a brief description of ARPKD and describes the various factors that place children with ARPKD at risk for neurological and neuropsychological impairment (e.g., a genetic condition leading to chronic kidney disease and eventual transplant; difficult-to-treat hypertension; eventual liver disease; possible dual transplantation of the kidneys and liver; chronic lung disease), including that these factors are present during a critical period of brain development. Further, the mini review discusses the available studies that have addressed the neurocognitive functioning in children with ARPKD. This paper concludes by providing the key clinical and research challenges that face the field of pediatric nephrology with respect to the clinical and scientific study of the neurocognitive functioning of children with ARPKD. Selected directions are offered in both the clinical and research arenas for this multiorgan chronic condition.

Arginine dimethylation products in pediatric patients with chronic kidney disease

Background

arginine and its metabolites have been linked to pediatric chronic kidney disease (CKD). We aimed to estimate serum levels of argninine (Arg), asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) in pediatric CKD patients and its relation to altered kidney function.

Patients and methods

132 pediatric patients with CKD and 120 healthy age and sex matched controls were compared regarding; serum Arg, ADMA and SDMA levels.

Results

In comparison to their values in control subjects, serum Arg levels were significantly lower; serum ADMA levels were non-significantly higher, but serum SDMA levels were significantly higher in CKD patients (p values: < 0.000; = 0.054; <0.000, respectively).

Calculated Arg/ADMA and Arg/SDMA ratios were significantly higher in patients compared to controls (p values: 0.001, and <0.000, respectively). However ADMA/SDMA ratio was significantly lower in patients compared to controls (p = 0.001. Serum Arg levels showed positive significant correlation, while serum ADMA and SDMA levels showed negative significant correlation with eGFR. Moreover, Arg/ADMA ratio showed negative significant correlation, while ADMA/SDMA ratio showed positive significant correlation with eGFR of patients. Regression analysis defined high serum SDMA level as persistently significant predictor for low eGFR.

Conclusion

Disturbed serum levels of arginine and its dimethyl derivatives may underlie development and/or progression of CKD. Elevated serum SDMA level is strongly correlated with impaired kidney functions and could be considered as a predictor for kidney functions deterioration and CKD progression.

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The underlying pathogenic mechanisms for pediatric CKD are multiple and interlocking.

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Disturbed serum levels of Arg and its dimethyl derivatives may underlie development and/or progression of CKD.

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Elevated serum SDMA level is strongly correlated with impaired kidney functions.

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Elevated SDMA level can be a predictor for kidney functions deterioration and CKD progression.

Physical activity and screen time in adolescents in the chronic kidney disease in children (CKiD) cohort

BACKGROUND

Self-reported physical activity (PA) and screen time exposure in adolescents with chronic kidney disease (CKD) has not been evaluated.

METHODS

We performed a cross-sectional analysis of PA and screen time in 224 adolescents at entry into the Chronic Kidney Disease in Children (CKiD) cohort. We compared proportions of CKiD vs. healthy 2012 National Health and Nutrition Examination Survey (NHANES) participants reporting the recommended 60 min of PA 7 days/week or ≤ 2 h/day of entertainment screen time (binomial probability test). Within CKiD, we assessed correlates of PA and screen time using multivariable logistic and linear regression and examined longitudinal data for 136 participants.

RESULTS

Median age of CKiD participants was 15 years, and 60 % were male. Median estimated glomerular filtration rate (eGFR) was 41.3 (IQR 30.8, 52.3) ml/min/1.73 m(2). Only 13 % of CKiD participants met recommendations for PA vs. 25 % of NHANES (p < 0.001), while 98 % in CKiD exceeded the recommended screen time vs. 73 % in NHANES (p < 0.001). Within CKiD, obesity (p = 0.04) and lower eGFR (p = 0.02) were independently associated with greater screen time.

CONCLUSIONS

Adolescents with CKD engage in significantly less PA and greater screen time than healthy youth in the United States, and this may worsen over time.

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.

Chronic kidney disease in children and adolescents in Brunei Darussalam

AIM: To determine epidemiology of Bruneian paediatric chronic kidney disease (CKD) patients and factors that affect growth and progression of disease.

METHODS: A cross-sectional study conducted on all children below 18 years old who were diagnosed with CKD over a ten year period (2004 to 2013). The reference population was all children (< 18 years old) suffering from CKD and attending the tertiary paediatric nephrology clinic in Brunei Darussalam. Demographic (current age, age of diagnosis, gender, ethnicity), anthropometric (weight and height), diagnosis, laboratory data (serum creatinine and haemoglobin, urinalysis) and blood pressure were extracted from the patients’ clinical case notes and recorded using a data collection form.

RESULTS: The study revealed a high national prevalence [736 per million child population (pmcp)] and incidence (91 pcmp) of CKD. If CKD was defined at Stage 1, 2, 3, 4 or 5, the associated prevalence figures were 736, 132, 83, 50 and 33 pmcp. Glomerulonephritis accounted for 69% of all prevalent cases, followed by congenital abnormalities of kidney and urinary tract (20%) and tubulointerstitial diseases (8%). Minimal change disease being the most common histological diagnosis. The median age of diagnosis was 4.5 years, with congenital disease patients experiencing an earlier onset of diagnosis. A large proportion of patients were below the 5% percentile for height and weight. Non-glomerular diseases, adolescent and female patients were significantly associated with poor growth, but not glomerular filtration rate, age of diagnosis or steroid usage.

CONCLUSION: Brunei has a high prevalence of chronic kidney disease in the paediatric population with glomerulonephritis being the most common disease.

Obsessive Compulsive Inventory-Child Version (OCV-CI) to Evaluate Obsessive Compulsive Disorder in Children With Early Stages of Chronic Kidney Disease: A Case Control Study

Background:

Chronic kidney disease (CKD) is a common medical condition among children and obsessive-compulsive disorder (OCD) is a frequent, chronic, costly, and disabling disorder among them.

Objectives:

The aim of this study was to investigate obsessive-compulsive disorder (OCD) in children with early stages of CKD, and to compare it with the occurrence of OCD in healthy children.

Patients and Methods:

In this case-control study, we evaluated 160 children aged 7 to 17 years old who were visited in the pediatric clinics of Amir-Kabir hospital, Arak, Iran. The control group consisted of 80 healthy children and the case group included 80 children with Stage 1 to 3 CKD. The ages and sex of the children in the two groups were matched. OCD in children was evaluated using the obsessive compulsive inventory-child version (OCI-CV).

Results:

The mean scores of doubting/checking (case: 3.52 ± 2.54, control: 2.5 ± 2.32, P = 0.007) and ordering (case: 2.59 ± 1.81, control: 1.5 ± 2.56, P = 0.005) in the children with CKD was significantly higher than in the healthy ones. Moreover, the mean total scores for the OCI-CV of the children with CKD at 15.32 ± 7.69 was significantly higher than the scores of the healthy ones at 11.12 ± 2.54 (P = 0.021). There was a significant correlation between the CKD duration and doubting/checking (P = 0.004, correlation coefficient (CC): 0.4), obsessing (P = 0.06, CC: 0.02), washing (P = 0.031, CC: 0.8), ordering (P = 0.001, CC: 0.2), and the total scores of the OCI-CV questionnaire (P = 0.04, CC: 0.4).

Conclusions:

The risk of OCD in children with CKD is significantly higher than that in healthy children. Although the results seem to suggest that psychiatric intervention can be helpful in treating OCD in children with CKD, further investigation into the medical condition is required so as to obtain more definitive conclusions.

Animal models of pediatric chronic kidney disease. Is adenine intake an appropriate model?

Pediatric chronic kidney disease (CKD) has peculiar features. In particular, growth impairment is a major clinical manifestation of CKD that debuts in pediatric age because it presents in a large proportion of infants and children with CKD and has a profound impact on the self-esteem and social integration of the stunted patients. Several factors associated with CKD may lead to growth retardation by interfering with the normal physiology of growth plate, the organ where longitudinal growth rate takes place. The study of growth plate is hardly possible in humans and justifies the use of animal models. Young rats made uremic by 5/6 nephrectomy have been widely used as a model to investigate growth retardation in CKD. This article examines the characteristics of this model and analyzes the utilization of CKD induced by high adenine diet as an alternative research protocol.

Attention deficit hyperactivity disorder in children with early stages of chronic kidney disease

BACKGROUND

Attention Deficit Hyperactivity Disorder (ADHD) is the most common childhood neurological disorder. This disorder is more prevalent in some chronic diseases. The aim of this study was to investigate ADHD in children with early stages of chronic kidney disease (CKD) and to compare it with healthy children.

METHODS

Seventy five 5-16-year-old children with early stages of CKD (stage 1, 2 and 3) and 75 healthy children without CKD were included in this case - control study as case and control groups, respectively. The participants were selected from those children who were referred to the pediatric clinic of Amir Kabir Hospital of Arak (Iran) in the form of simple probability and based on inclusion and exclusion criteria. ADHD was diagnosed using Conner's Parent Rating Scale - 48 (CPRS-48) and DSM-IV criteria and was confirmed by a psychologist consultant. Data were analyzed by Binomial test in SPSS18.

RESULTS

ADHD inattentive type was observed in 8 cases (10.6%) with CKD and 2 controls (2.6%) (p= 0.109). Moreover, in the case and control groups, 7 (9.3%) and 6 (8%) children were affected by ADHD hyperactiveimpulsive type (p= 0.997), and 9 (12%) and 12 (16%) children were affected by ADHD mixed type (p= 0.664), respectively.

CONCLUSION

No differences were found between the prevalence of ADHD in the children with early stages of CKD and the control group. However, due to the importance of the relationships between different types of psychiatric disorders and CKD and lack of enough evidence concerning the relationship between ADHD and different stages of CKD in children, conducting further studies in this field is recommended.

Developing a framework for evaluating kidney transplantation candidacy in children with multiple comorbidities

Children with multiple comorbidities, including neurodevelopmental delay, can develop end-stage kidney disease (ESKD). When and if these children should be eligible for kidney transplantation is an area of debate within the pediatric nephrology community and the public. Discussions focus on expected survival and quality of life posttransplant, as well as resource allocation decisions, as donor kidneys remain a limited resource. This paper focuses on the evidence available regarding outcomes in this population and the ethical issues that should be considered. The authors offer a framework for transplant teams evaluating children with comorbidities for kidney transplant, focusing on the benefits and burdens that transplantation can be expected to achieve.

Next-generation sequencing for research and diagnostics in kidney disease

The advent of next-generation sequencing technologies has enabled genetic nephrology research to move beyond single gene analysis to the simultaneous investigation of hundreds of genes and entire pathways. These new sequencing approaches have been used to identify and characterize causal factors that underlie inherited heterogeneous kidney diseases such as nephronophthisis and congenital anomalies of the kidney and urinary tract. In this Review, we describe the development of next-generation sequencing in basic and clinical research and discuss the implementation of this novel technology in routine patient management. Widespread use of targeted and nontargeted approaches for gene identification in clinical practice will require consistent phenotyping, appropriate disease modelling and collaborative efforts to combine and integrate data analyses. Next-generation sequencing is an exceptionally promising technique that has the potential to improve the management of patients with inherited kidney diseases. However, identifying the molecular mechanisms that lead to renal developmental disorders and ciliopathies is difficult. A major challenge in the near future will be how best to integrate data obtained using next-generation sequencing with personalized medicine, including use of high-throughput disease modelling as a tool to support the clinical diagnosis of kidney diseases.

Proteomics in acute kidney injury--current status and future promise

Pediatric acute kidney injury (AKI) is associated with increased morbidity, mortality and associated healthcare costs. Unfortunately, there are currently no effective therapies available, and this has been attributed in part to the late diagnosis of AKI. Therefore, significant efforts have been made to develop early diagnostic tools for AKI in the hope that early identification of renal injury will allow for effective therapeutic intervention. Different transcriptomic, proteomic and metabolomic technologies offer unbiased approaches to identifying novel biomarkers of AKI. This review will provide an overview of non-invasive pediatric AKI biomarkers. It will focus on unbiased technologies by using examples of biomarkers identified with "-omic" technologies and different methodological and implementation challenges will be highlighted. Finally, emerging proteomic techniques that may be applicable to biomarker discovery will be presented. Ultimately, the development of novel biomarkers of AKI may lead to the early diagnosis and effective therapeutic intervention of AKI to improve patient outcomes.

Geographic determinants of access to pediatric deceased donor kidney transplantation

Children receive priority in the allocation of deceased donor kidneys for transplantation in the United States, but because allocation begins locally, geographic differences in population and organ supply may enable variation in pediatric access to transplantation. We assembled a cohort of 3764 individual listings for pediatric kidney transplantation in 2005-2010. For each donor service area, we assigned a category of short (<180 days), medium (181-270 days), or long (>270 days) median waiting time and calculated the ratio of pediatric-quality kidneys to pediatric candidates and the percentage of these kidneys locally diverted to adults. We used multivariable Cox regression analyses to examine the association between donor service area characteristics and time to deceased donor kidney transplantation. The Kaplan-Meier estimate of median waiting time to transplantation was 284 days (95% confidence interval, 263 to 300 days) and varied from 14 to 1313 days across donor service areas. Overall, 29% of pediatric-quality kidneys were locally diverted to adults. Compared with areas with short waiting times, areas with long waiting times had a lower ratio of pediatric-quality kidneys to candidates (3.1 versus 5.9; P<0.001) and more diversions to adults (31% versus 27%; P<0.001). In multivariable regression, a lower kidney to candidate ratio remained associated with longer waiting time (hazard ratio, 0.56 for areas with <2:1 versus reference areas with ≥5:1 kidneys/candidates; P<0.01). Large geographic variation in waiting time for pediatric deceased donor kidney transplantation exists and is highly associated with local supply and demand factors. Future organ allocation policy should address this geographic inequity.

B-type natriuretic peptides are reliable markers of cardiac strain in CKD pediatric patients

Myocardial damage and strain are common in children with chronic renal failure. The most prevalent pathologies, as defined by echocardiography, are left ventricular hypertrophy (LVH), diastolic and systolic dysfunction, and altered LV geometry. Troponin I and T, as well as B-type natriuretic peptide (BNP) and its cleavage fragment NT-proBNP, are known to be good markers of myocardial damage and stress, respectively, in the general adult population and among those with chronic kidney disease (CKD). In this study we measured the levels of troponins I and T, BNP, and NT-proBNP in a group of children and young adults with CKD stages 3-5 and determined their respective correlations with echocardiographic and laboratory abnormalities. BNP and NT-proBNP levels and their log values correlated well with the following parameters: diastolic blood pressure, estimated glomerular filtration rate, time-averaged hemoglobin levels, and LV mass. Both BNP and NT-proBNP levels, but not those of either troponin, were found to be reliable surrogate markers of strained hearts, defined as having LVH or diastolic or systolic dysfunction, in the pediatric CKD stages 3-4 group. The log NT-proBNP value was also found to be a good marker of cardiac strain in the CKD stage 5 group of patients. Serum BNP and NT-proBNP threshold concentrations of 43 and 529 pg/ml, respectively, were found to have the best sensitivity and specificity in predicting strained hearts. Based on these findings, we conclude that both BNP and NT-proBNP levels, but not those of troponins I and T, can serve as inexpensive, simple, and reliable markers of stressed hearts in the pediatric CKD patient population.

Epidemiology of chronic kidney disease in children

In the past 30 years there have been major improvements in the care of children with chronic kidney disease (CKD). However, most of the available epidemiological data stem from end-stage renal disease (ESRD) registries and information on the earlier stages of pediatric CKD is still limited. The median reported incidence of renal replacement therapy (RRT) in children aged 0-19 years across the world in 2008 was 9 (range: 4-18) [corrected] per million of the age-related population). [corrected] The prevalence of RRT in 2008 ranged from 18 to 100 per million of the age-related population. Congenital disorders, including congenital anomalies of the kidney and urinary tract (CAKUT) and hereditary nephropathies, are responsible for about two thirds of all cases of CKD in developed countries, while acquired causes predominate in developing countries. Children with congenital disorders experience a slower progression of CKD than those with glomerulonephritis, resulting in a lower proportion of CAKUT in the ESRD population compared with less advanced stages of CKD. Most children with ESRD start on dialysis and then receive a transplant. While the survival rate of children with ERSD has improved, it remains about 30 times lower than that of healthy peers. Children now mainly die of cardiovascular causes and infection rather than from renal failure.

Exercise for children with chronic kidney disease and end-stage renal disease

It is well known that adults suffering from chronic kidney disease (CKD) experience muscle wasting and excessive fatigue, which results in a reduced exercise capacity and muscle weakness compared to their healthy counterparts, but research suggests that this can be improved through exercise. There is very limited data available regarding exercise tolerance in children with CKD and even less on the effects of exercise training programs. However, the available evidence does suggest that like adults, children also suffer from poor exercise capacity and reduced muscle strength, although the reasons for these limitations remain unclear. Studies that have attempted to implement exercise training programs in pediatric CKD populations have experienced high dropout rates, suggesting that the approach used to implement such programs in children needs to be different from the approach used for adults. This review summarizes the current knowledge regarding exercise capacity and muscle strength in children with CKD, the methods used to perform these assessments, and the possible causes of physical limitations. The results of exercise training studies, and the potential reasons as to why training programs have proved relatively unsuccessful are also discussed.

The association between abnormal birth history and growth in children with CKD

BACKGROUND AND OBJECTIVES

Poor linear growth is a well described complication of chronic kidney disease (CKD). This study evaluated whether abnormal birth history defined by low birth weight (LBW; <2500 g), prematurity (gestational age <36 weeks), small for gestational age (SGA; birth weight <10th percentile for gestational age), or intensive care unit (ICU) at birth were risk factors for poor growth outcomes in children with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Growth outcomes were quantified by age-sex-specific height and weight z-scores during 1393 visits from 426 participants of the Chronic Kidney Disease in Children Study, an observational cohort of children with CKD. Median baseline GFR was 42.9 ml/min per 1.73 m(2), 21% had a glomerular diagnosis, and 52% had CKD for ≥ 90% of their lifetime.

RESULTS

A high prevalence of LBW (17%), SGA (14%), prematurity (12%), and ICU after delivery (40%) was observed. Multivariate analyses demonstrated a negative effect of LBW (-0.43 ± 0.14; P < 0.01 for height and -0.37 ± 0.16; P = 0.02 for weight) and of SGA (-0.29 ± 0.16; P = 0.07 for height and -0.41 ± 0.19; P = 0.03 for weight) on current height and weight. In children with glomerular versus nonglomerular diagnoses, the effect of SGA (-1.08 versus -0.18; P = 0.029) on attained weight was more pronounced in children with a glomerular diagnosis.

CONCLUSIONS

LBW and SGA are novel risk factors for short stature and lower weight percentiles in children with mild to moderate CKD independent of kidney function.

Pediatric renal supportive therapies: the changing face of pediatric renal replacement approaches

PURPOSE OF REVIEW

The term 'renal replacement therapy' has been employed for describing dialytic interventions for acute and chronic patients. The implications of this terminology do not correctly reflect the extent that we are able to address native renal function. Provision of correct terminology to describe dialytic therapies may provide insight and investigation into the 'nonreplaceable' aspects of renal function in the acute and chronic settings.

RECENT FINDINGS

The terms 'chronic kidney disease' and 'acute kidney injury' have replaced the terms chronic renal failure and acute renal failure, respectively. Changing terminology has improved definitions and clinical care in these patient groups. Improvements in dialytic therapies have not been paralleled by changes in our understanding of the native renal function components that are not replaced during dialysis.

SUMMARY

A paradigm shift in our understanding of replacement of renal function is necessary. The terminology of 'renal replacement therapy' should be supplanted by more appropriate terminology, 'renal supportive therapy'. The benefits of employing terminology that adequately reflects the extent to which we can offer supportive dialytic treatment to our acute and chronic patients may be realized as a significant stimulus for scientific investigation and clinical care improvements.