Height at First RRT and Mortality in Children

Nutritional profile and infection-related hospital admissions in children with chronic kidney disease

BACKGROUND

Protein energy wasting (PEW) and undernutrition are highly prevalent in children with chronic kidney disease (CKD), but their impact on clinical outcomes is not well described. This prospective longitudinal study in children with CKD assessed the association of nutritional parameters with infection-related hospital admissions (IRHA).

METHODS

Children with CKD2-5D aged 2-18 years and infection-free for 1 month were recruited over 5 years. Evaluation for undernutrition by subjective global nutritional assessment and for PEW using paediatric criteria was undertaken and categorized as mild (>2 criteria), standard (>3 criteria) and modified PEW (>3 criteria with short stature). The IRHA (severe viral, bacterial or fungal infections) were recorded.

RESULTS

Among 137 children (45 on dialysis; age 123 ± 46 months; 70% males), undernutrition was seen in 60% and PEW in 52%. In over 38 ± 21 months follow-up, 107 (78%) required hospital admissions (67% IRHA). The incidence rate of IRHA in days per patient-year was higher in those with undernutrition compared to well-nourished children [1.74 (1.27, 2.31) vs. 0.65 (0.44, 0.92) p < 0.0001] and higher in those with PEW compared to no PEW [1.74 (1.30, 2.28) vs. 0.56 (0.36, 0.82) p < 0.0001] respectively. On adjusted analysis, independent risk factors for IRHA were undernutrition, low BMI, hypoalbuminemia and dialysis status with modified PEW [OR 5.34 (2.16, 13.1) p < 0.001] and raised CRP [OR 4.66 (1.56, 13.9) p = 0.006] having the highest risk. Additionally, modified PEW and BMI were noted to have a twofold risk for recurrent infections.

CONCLUSION

In children with CKD2-5D, incidence rate of IRHA was significantly higher in those with undernutrition and PEW. While dialysis, poor nutritional status and inflammation were risk factors for IRHA, modified PEW and BMI were associated with recurrent infections.

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.

Role of Nutrients in Pediatric Non-Dialysis Chronic Kidney Disease: From Pathogenesis to Correct Supplementation

Nutrition management is fundamental for children with chronic kidney disease (CKD). Fluid balance and low-protein and low-sodium diets are the more stressed fields from a nutritional point of view. At the same time, the role of micronutrients is often underestimated. Starting from the causes that could lead to potential micronutrient deficiencies in these patients, this review considers all micronutrients that could be administered in CKD to improve the prognosis of this disease.

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.

Longitudinal Relationship Between Anemia and Statural Growth Impairment in Children and Adolescents With Nonglomerular CKD: Findings From the Chronic Kidney Disease in Children (CKiD) Study

RATIONALE & OBJECTIVE

Anemia and statural growth impairment are both prevalent in children with nonglomerular chronic kidney disease (CKD) and are associated with poor quality of life and increased morbidity and mortality. However, to date no longitudinal studies have demonstrated a relationship between anemia and statural growth in this population.

STUDY DESIGN

The CKD in Children (CKiD) study is a multicenter prospective cohort study with over 15 years of follow-up observation.

SETTING & PARTICIPANTS

CKiD participants younger than 22 years with nonglomerular CKD who had not reached final adult height.

EXPOSURE

Age-, sex-, and race-specific hemoglobin z score.

OUTCOME

Age- and sex-specific height z score.

ANALYTICAL APPROACH

The relationship between hemoglobin and height was quantified using (1) multivariable repeated measures paired person-visit analysis, and (2) multivariable repeated measures linear mixed model analysis. Both models were adjusted for age, sex, body mass index, estimated glomerular filtration rate, acidosis, and medication use.

RESULTS

Overall, 67% of the 510 participants studied had declining hemoglobin z score trajectories over the follow-up period, which included 1,763 person-visits. Compared with average hemoglobin z scores of≥0, average hemoglobin z scores of less than -1.0 were independently associated with significant growth impairment at the subsequent study visit, with height z score decline ranging from 0.24 to 0.35. Importantly, in 50% of cases hemoglobin z scores of less than -1.0 corresponded to hemoglobin values higher than those used as cutoffs defining anemia in the KDIGO clinical practice guideline for anemia in CKD. When stratified by age, the magnitude of the association peaked in participants aged 9 years. In line with paired-visit analyses, our mixed model analysis demonstrated that in participants with baseline hemoglobin z score less than -1.0, a hemoglobin z score decline over the follow-up period was associated with a statistically significant concurrent decrease in height z score.

LIMITATIONS

Limited ability to infer causality.

CONCLUSIONS

Hemoglobin decline is associated with growth impairment over time in children with mild to moderate nonglomerular CKD, even before hemoglobin levels reach the cutoffs that are currently used to define anemia in this population.

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.

Epidemiology of pediatric chronic kidney disease/kidney failure: learning from registries and cohort studies

Although the concept of chronic kidney disease (CKD) in children is similar to that in adults, pediatric CKD has some peculiarities, and there is less evidence and many factors that are not clearly understood. The past decade has witnessed several additional registry and cohort studies of pediatric CKD and kidney failure. The most common underlying disease in pediatric CKD and kidney failure is congenital anomalies of the kidney and urinary tract (CAKUT), which is one of the major characteristics of CKD in children. The incidence/prevalence of CKD in children varies worldwide. Hypertension and proteinuria are independent risk factors for CKD progression; other factors that may affect CKD progression are primary disease, age, sex, racial/genetic factors, urological problems, low birth weight, and social background. Many studies based on registry data revealed that the risk factors for mortality among children with kidney failure who are receiving kidney replacement therapy are younger age, female sex, non-White race, non-CAKUT etiologies, anemia, hypoalbuminemia, and high estimated glomerular filtration rate at dialysis initiation. The evidence has contributed to clinical practice. The results of these registry-based studies are expected to lead to new improvements in pediatric CKD care.

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.

Targeting optimal PD management in children: what have we learned from the IPPN registry?

National and international registries have great potential for providing data that describe disease burden, treatments, and outcomes especially in rare diseases. In the setting of pediatric end-stage renal disease (ESRD), the available data are limited to highly developed countries, whereas the lack of data from emerging economies blurs the global perspective. In order to improve the pediatric dialysis care worldwide, provide global benchmarking of pediatric dialysis outcome, and assign useful tools and management algorithms based on evidence-based medicine, the International Pediatric Peritoneal Dialysis Network (IPPN) was established in 2007. In recent years, the Registry has provided comprehensive data on relevant clinical issues in pediatric peritoneal dialysis patients including nutritional status, growth, cardiovascular disease, anemia management, mineral and bone disorders, preservation of residual kidney function, access-related complications, and impact of associated comorbidities. A unique feature of the registry is the ability to compare practices and outcomes between countries and world regions. In the current review, we describe study design and collection methods, summarize the core IPPN findings based on its 12-year experience and 13 publications, and discuss the future perspective.

Determinants of growth after kidney transplantation in prepubertal children

BACKGROUND

Short stature is a frequent complication after pediatric kidney transplantation (KT). Whether the type of transplantation and prior treatment with recombinant human growth hormone (GH) affects post-transplant growth, is unclear.

METHODS

Body height, leg length, sitting height, and sitting height index (as a measure of body proportions) were prospectively investigated in 148 prepubertal patients enrolled in the CKD Growth and Development study with a median follow-up of 5.0 years. We used linear mixed-effects models to identify predictors for body dimensions.

RESULTS

Pre-transplant Z scores for height (- 2.18), sitting height (- 1.37), and leg length (- 2.30) were reduced, and sitting height index (1.59) was increased compared to healthy children, indicating disproportionate short stature. Catch-up growth in children aged less than 4 years was mainly due to stimulated trunk length, and in older children to improved leg length, resulting in normalization of body height and proportions before puberty in the majority of patients. Use of GH in the pre-transplant period, congenital CKD, birth parameters, parental height, time after KT, steroid exposure, and transplant function were significantly associated with growth outcome. Although, unadjusted growth data suggested superior post-transplant growth after (pre-emptive) living donor KT, this was no longer true after adjusting for the abovementioned confounders.

CONCLUSIONS

Catch-up growth after KT is mainly due to stimulated trunk growth in young children (< 4 years) and improved leg growth in older children. Beside transplant function, steroid exposure and use of GH in the pre-transplant period are the main potentially modifiable factors associated with better growth outcome.

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.

Strategies for Optimizing Growth in Children With Chronic Kidney Disease

Growth failure is a hallmark in children with chronic kidney disease (CKD). Therefore, early diagnosis and adequate management of growth failure is of utmost importance in these patients. The risk of severe growth retardation is the higher the younger the child is, which places an additional burden on patients and their families and hampers the psychosocial integration of these children. Careful monitoring of growth, and effective interventions are mandatory to prevent and treat growth failure in children with CKD at all ages and all stages of kidney failure. Early intervention is critical, as all therapeutic interventions are much more effective if they are started prior to the initiation of dialysis. Prevention and treatment of growth failure focuses on: (i) preservation of renal function, e.g., normalization of blood pressure and proteinuria by use of inhibitors of the renin-angiotensin aldosterone system, (ii) adequate energy intake, including tube feeding or gastrostomy in case of persisting malnutrition, (iii) substitution of water and electrolytes, especially in children with renal malformation, (iv) correction of metabolic acidosis, (v) control of parathyroid hormone levels within the CKD-dependent target range, (vi) use of recombinant human growth hormone in cases of persistent growth failure, and, (vii) early/preemptive kidney transplantation using steroid-minimizing immunosuppressive protocols in children with end-stage CKD. This review discusses these measures based on recent guidelines.

Evaluation of carotid intima-media thickness and factors associated with cardiovascular disease in children and adolescents with chronic kidney disease

OBJECTIVE

To assess the carotid intima-media thickness and factors associated with cardiovascular disease in children and adolescents with chronic kidney disease.

MATERIAL AND METHODS

Observational, cross-sectional study carried out at the Universidade Federal de São Paulo (chronic kidney disease outpatient clinics) with 55 patients (60% males) with a median age of 11.9 years (I25-I75: 9.2-14.8 years). Of the 55 patients, 43 were on conservative treatment and 12 were on dialysis. Serum laboratory parameters (creatinine, uric acid, C-reactive protein, total cholesterol and fractions, and triglycerides), nutritional status (z-score of body mass index, z-score of height/age), body fat (fat percentage and waist circumference), and blood pressure levels were evaluated. The carotid intima-media thickness measure was evaluated by a single ultrasonographer and compared with percentiles established according to gender and height. Data collection was performed between May 2015 and March 2016.

RESULTS

Of the children and adolescents with chronic kidney disease, 74.5% (95% CI: 61.0; 85.3) showed an increase (>P95) in carotid intima-media thickness. In patients with stages I and II hypertension, 90.9% had increased carotid intima-media thickness. Nutritional status, body fat and laboratory tests were not associated with increased carotid intima-media thickness. After multivariate adjustment, only puberty (PR=1.30, p=0.037) and stages I and II arterial hypertension (PR=1.42, p=0.011) were independently associated with carotid intima-media thickness alterations.

CONCLUSION

The prevalence of increased carotid thickness was high in children and adolescents with chronic kidney disease. Puberty and arterial hypertension were independently associated with increased carotid intima-media thickness.

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.

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.

Determinants of Statural Growth in European Children With Chronic Kidney Disease: Findings From the Cardiovascular Comorbidity in Children With Chronic Kidney Disease (4C) Study

Failure of statural growth is one of the major long-term sequelae of chronic kidney disease (CKD) in children. In recent years effective therapeutic strategies have become available that lead to evidence based practice recommendations. To assess the current growth performance of European children and adolescents with CKD, we analyzed a cohort of 594 patients from 12 European countries who were followed prospectively for up to 6 years in the 4C Study. While all patients were on conservative treatment with a mean estimated glomerular filtration rate of 28 ml/min/1.73 m² at study entry, 130 children commenced dialysis during the observation period. At time of enrolment the mean height standard deviation score (SDS) was -1.57; 36% of patients had a height below the third percentile. The prevalence of growth failure varied between countries from 7 to 44% Whereas patients on conservative treatment showed stable growth, height SDS gradually declined on those on dialysis. Parental height, pubertal status and treatment with recombinant growth hormone (GH) were positively, and the diagnosis of syndromic disease and CKD stage were negatively associated with height SDS during the observation period. Unexpectedly, higher body mass index (BMI) SDS was associated with lower height SDS both at enrolment and during follow up. Renal anemia, metabolic acidosis, and hyperparathyroidism were mostly mild and not predictive of growth rates by multivariable analysis. GH therapy was applied in only 15% of growth retarded patients with large variation between countries. When adjusting for all significant covariates listed above, the country of residence remained a highly significant predictor of overall growth performance. In conclusion, growth failure remains common in European children with CKD, despite improved general management of CKD complications. The widespread underutilization of GH, an approved efficacious therapy for CKD-associated growth failure, deserves further exploration.

Survival in children requiring chronic renal replacement therapy

Survival in the pediatric end-stage renal disease (ESRD) population has improved substantially over recent decades. Nonetheless, mortality remains at least 30 times higher than that of healthy peers. Patient survival is multifactorial and dependent on various patient and treatment characteristics and degree of economic welfare of the country in which a patient is treated. In this educational review, we aim to delineate current evidence regarding mortality risk in the pediatric ESRD population and provide pediatric nephrologists with up-to-date information required to counsel affected families.

Clinical outcomes and survival in pediatric patients initiating chronic dialysis: a report of the NAPRTCS registry

BACKGROUND

The 2011 annual report of the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) registry comprises data on 6482 dialysis patients over the past 20 years of the registry.

METHODS

The study compared clinical parameters and patient survival in the first 10 years of the registry (1992-2001) with the last decade of the registry (2002-2011).

RESULTS

There was a significant increase in hemodialysis as the initiating dialysis modality in the most recent cohort (42% vs. 36%, p < 0.001). Patients in the later cohort were less likely to have a hemoglobin <10 g/dl [odds ratio (OR) 0.68; confidence interval (CI) 0.58-0.81; p < 0.001] and height z-score <2 standard deviations (SD) below average (OR 0.68, CI 0.59-0.78, p < 0.0001). They were also more likely to have a parathyroid hormone (PTH) level two times above the upper limits of normal (OR 1.39, CI 1.21-1.60, p < 0.0001). Although hypertension was common regardless of era, patients in the 2002-2011 group were less likely to have blood pressure >90th percentile (OR 1.39, CI 1.21-1.60, p < 0.0001), and a significant improvement in survival at 36 months after dialysis initiation was observed in the 2002-2011 cohort compared with the 1992-2001 cohort (95% vs. 90%, respectively). Cardiopulmonary causes were the most common cause of death in both cohorts. Young age, growth deficit, and black race were poor predictors of survival.

CONCLUSIONS

The survival of pediatric patients on chronic dialysis has improved over two decades of dialysis registry data, specifically for children <1year.

Associations Between Weight Loss, Kidney Function Decline, and Risk of ESRD in the Chronic Kidney Disease in Children (CKiD) Cohort Study

BACKGROUND

Anorexia and malnutrition are associated with poor outcomes in children with chronic kidney disease (CKD).

STUDY DESIGN

Observational cohort study.

SETTING & PARTICIPANTS

We assessed changes in body mass index (BMI) as kidney function declines and its association with risk for end-stage renal disease (ESRD) among 854 participants followed between 2005 to 2013 in the CKD in Children (CKiD) Study.

PREDICTORS

Repeated measurements of estimated glomerular filtration rate (eGFR) by serum creatinine concentration in our trajectory analysis using mixed models; change in BMI z score (per year) after eGFR decreased to <35mL/min/1.73m² in logistic regression models.

OUTCOMES

Repeated measurements of BMI z score (as a reflection of weight status) in our trajectory analysis; ESRD in logistic regression models.

RESULTS

During a mean longitudinal follow-up of 3.4 years, BMI z scores remained stable until eGFR decreased to <35mL/min/1.73m². When eGFR decreased to <35mL/min/1.73m², a mean decline in BMI z score of 0.13 (95% CI, 0.09-0.17) was noted with each 10-mL/min/1.73m² further decline in eGFR. This was statistically significantly different from the weight trajectory when eGFR was ≥35mL/min/1.73 m² (P<0.001). Among children and adolescents with significant weight loss (defined as decline in BMI z score > 0.2 per year) after eGFR decreased to <35mL/min/1.73m², the odds of ESRD was 3.28 (95% CI, 1.53-7.05) times greater compared with participants with stable BMI z scores (BMI z score change per year of 0-0.1).

LIMITATIONS

Observational nature of our study, lack of longitudinal assessments of inflammatory markers.

CONCLUSIONS

In children and adolescents with CKD, weight loss mostly occurs when eGFR decreases to <35mL/min/1.73m², and this weight loss was associated with higher risk for ESRD. Further studies are needed to define the reasons for the association between weight loss and more rapid progression to ESRD in children and adolescents.

Care of the Pediatric Patient on Chronic Dialysis

Optimal care of the pediatric end-stage renal disease (ESRD) patient on chronic dialysis is complex and requires multidisciplinary care as well as patient/caregiver involvement. The dialysis team, along with the family and patient, should all play a role in choosing the dialysis modality which best meets the patient's needs, taking into account special considerations and management issues that may be particularly pertinent to children who receive peritoneal dialysis or hemodialysis. Meticulous attention to dialysis adequacy in terms of solute and fluid removal, as well as to a variety of clinical manifestations of ESRD, including anemia, growth and nutrition, chronic kidney disease-mineral bone disorder, cardiovascular health, and neurocognitive development, is essential. This review highlights current recommendations and advances in the care of children on dialysis with a particular focus on preventive measures to minimize ESRD-associated morbidity and mortality. Advances in dialysis care and prevention of complications related to ESRD and dialysis have led to better survival for pediatric patients on dialysis.

Chronic dialysis in children and adolescents: challenges and outcomes

Chronic dialysis is rarely required during childhood. Despite technical advances that have facilitated the treatment of even the youngest children, morbidity and mortality remain higher with chronic dialysis than after renal transplantation. The cost of equipment and skilled personnel to provide the service compromises the availability of such dialysis in parts of the world where financial resources are constrained. This Review describes the incidence and causes of end-stage kidney disease in children on long-term dialysis, and highlights management issues, including dialysis modality selection, complications, and patient outcome data.

Lack of hepcidin ameliorates anemia and improves growth in an adenine-induced mouse model of chronic kidney disease

Growth delay is common in children with chronic kidney disease (CKD), often associated with poor quality of life. The role of anemia in uremic growth delay is poorly understood. Here we describe an induction of uremic growth retardation by a 0.2% adenine diet in wild-type (WT) and hepcidin gene (Hamp) knockout (KO) mice, compared with their respective littermates fed a regular diet. Experiments were started at weaning (3 wk). After 8 wk, blood was collected and mice were euthanized. Adenine-fed WT mice developed CKD (blood urea nitrogen 82.8 ± 11.6 mg/dl and creatinine 0.57 ± 0.07 mg/dl) and were 2.1 cm shorter compared with WT controls. WT adenine-fed mice were anemic and had low serum iron, elevated Hamp, and elevated IL6 and TNF-α. WT adenine-fed mice had advanced mineral bone disease (serum phosphorus 16.9 ± 3.1 mg/dl and FGF23 204.0 ± 115.0 ng/ml) with loss of cortical and trabecular bone volume seen on microcomputed tomography. Hamp disruption rescued the anemia phenotype resulting in improved growth rate in mice with CKD, thus providing direct experimental evidence of the relationship between Hamp pathway and growth impairment in CKD. Hamp disruption ameliorated CKD-induced growth hormone-insulin-like growth factor 1 axis derangements and growth plate alterations. Disruption of Hamp did not mitigate the development of uremia, inflammation, and mineral and bone disease in this model. Taken together, these results indicate that an adenine diet can be successfully used to study growth in mice with CKD. Hepcidin appears to be related to pathways of growth retardation in CKD suggesting that investigation of hepcidin-lowering therapies in juvenile CKD is warranted.