Severe left ventricular hypertrophy in pediatric dialysis: prevalence and predictors

Real-world evidence on the dosing and safety of C.E.R.A. in pediatric dialysis patients: findings from the International Pediatric Dialysis Network registries

BACKGROUND

This retrospective real-world study used data from two registries, International Pediatric Peritoneal Dialysis Network (IPPN) and International Pediatric Hemodialysis Network (IPHN), to characterize the efficacy and safety of continuous erythropoietin receptor activator (C.E.R.A.) in pediatric patients with chronic kidney disease (CKD) on peritoneal dialysis (PD) or hemodialysis (HD).

METHODS

IPPN and IPHN collect prospective data (baseline and every 6 months) from pediatric PD and HD centers worldwide. Demographics, clinical characteristics, dialysis information, treatment, laboratory parameters, number and causes of hospitalization events, and deaths were extracted for patients on C.E.R.A. treatment (IPPN: 2007-2021; IPHN: 2013-2021).

RESULTS

We analyzed 177 patients on PD (median age 10.6 years) and 52 patients on HD (median age 14.1 years) who had ≥ 1 observation while being treated with C.E.R.A. The median (interquartile range [IQR]) observation time under C.E.R.A. exposure was 6 (0-12.5) and 12 (0-18) months, respectively. Hemoglobin concentrations were stable over time; respective means (standard deviation) at last observation were 10.9 (1.7) g/dL and 10.4 (1.7) g/dL. Respective median (IQR) monthly C.E.R.A. doses at last observation were 3.5 (2.3-5.1) µg/kg, or 95 (62-145) µg/m2 and 2.1 (1.2-3.4) µg/kg, or 63 (40-98) µg/m2. Non-elective hospitalizations occurred in 102 (58%) PD and 32 (62%) HD patients. Seven deaths occurred (19.8 deaths per 1000 observation years).

CONCLUSIONS

C.E.R.A. was associated with efficient maintenance of hemoglobin concentrations in pediatric patients with CKD on dialysis, and appeared to have a favorable safety profile. The current analysis revealed no safety signals.

ROS-Activated TRPM2 Channel: Calcium Homeostasis in Cardiovascular/renal System and Speculation in Cardiorenal Syndrome

The transient receptor potential melastatin 2 (TRPM2) channel is a nonselective calcium channel that is sensitive to oxidative stress (OS), and is widely expressed in multiple organs, such as the heart, kidney, and brain, which is inextricably related to calcium dyshomeostasis and downstream pathological events. Due to the increasing global burden of kidney or cardiovascular diseases (CVDs), safe and efficient drugs specific to novel targets are imperatively needed. Notably, investigation of the possibility to regard the TRPM2 channel as a new therapeutic target in ROS-related CVDs or renal diseases is urgently required because the roles of the TRPM2 channel in heart or kidney diseases have not received enough attention and thus have not been fully elaborated. Therefore, we aimed to review the involvement of the TRPM2 channel in cardiovascular disorders related to kidney or typical renal diseases and attempted to speculate about TRPM2-mediated mechanisms of cardiorenal syndrome (CRS) to provide representative perspectives for future research about novel and effective therapeutic strategies.

Nephrectomy improves both antihypertensive requirement and left ventricular mass for pediatric renal hypertension

BACKGROUND

Renal hypertension causes left ventricular (LV) hypertrophy leading to cardiomyopathy. Nephrectomy has been utilized to improve blood pressure and prepare for kidney transplantation in the pediatric population. We sought to investigate antihypertensive medication (AHM) requirement and LV mass in patients undergoing nephrectomy with renal hypertension.

METHODS

We performed a single institution retrospective review from 2009 to 2021 of children who have undergone nephrectomy for hypertension. Primary outcome was decrease in number of AHM. Secondary outcomes included change in LV mass and elimination of AHM. LV mass was measured using echocardiogram area-length and linear measurements. Non-parametric analyses were utilized to assess significance.

RESULTS

Thirty-one patients underwent nephrectomy. Median age was 12.5 years (0.8-19 years). Median of 3 AHM (range 1-5 medications) were used pre-operatively and patients had been managed for median 2.5 years. Twenty-nine had preoperative echocardiogram. Forty-eight percent of patients had LVH at nephrectomy. Median AHM after surgery was 1 (range 0-4 medications) at 30 days and 12 months, (p < 0.001). By 12 months after nephrectomy, 79.2% of patients had decreased the number of AHM. Eight (26%) patients were on no AHM 30 days after surgery, and 13 (43%) at 12 months. Systemic vascular disease and multicystic dysplastic kidney were the only factors associated with lack of improvement in AHM (p = 0.040). Fourteen patients had pre- and post-operative echocardiogram and 11 (79%) had improvement in LV mass (p = 0.016, 0.035).

CONCLUSIONS

Nephrectomy is effective in improving LV mass and reducing AHM for children with renal hypertension. Improvement is less likely in patients with systemic vascular disease and multicystic dysplastic kidneys. A higher resolution version of the Graphical abstract is available as Supplementary information.

Survival analysis among pediatric patients receiving kidney replacement therapy: a Japanese nationwide cohort study

BACKGROUND

Limited data are available on the survival and causes of death in pediatric patients with chronic kidney disease (CKD) stage 5 receiving kidney replacement therapy (KRT) in Asia.

METHODS

Data were obtained from the Japanese nationwide cross-sectional CKD stage 5 survey on pediatric patients (<20 years of age) who started KRT from 2006 to 2013. The cohort was divided into three groups according to age at the start of KRT: <1, 1-5, and 6-19 years.

RESULTS

Among the 701 children who were included, 59.3% were boys. Peritoneal dialysis was the most common initial modality of KRT (60.3%). Median age at KRT initiation was 10.2 years. Infants (<1 year old) accounted for 16.0% of the total cohort. Overall survival at 1 and 5 years was 97.2% and 92.5%, respectively. Infants had significantly lower survival rates than the other groups (hazard ratio, 5.35; 95% CI, 2.60-11.03; P < 0.001). In contrast, after the age of 1 year, the survival rate improved and did not differ from that of other age groups. The most common causes of death were infection (35.9%) and sudden death (15.4%).

CONCLUSIONS

The overall survival rate of pediatric patients with CKD stage 5 in Japan is like that in other high-income countries. Age at initiation of KRT is an important factor affecting survival since the poorest survival rate was observed in infants. Further improvement in infant dialysis therapy is still needed to improve survival of the youngest children. A higher resolution version of the Graphical abstract is available as Supplementary information.

Echocardiogram screening in pediatric dialysis and transplantation

Transthoracic echocardiography is commonly used to identify structural and functional cardiac abnormalities that can be prevalent in childhood chronic kidney failure (KF). Left ventricular mass (LVM) increase is most frequently reported and may persist post-kidney transplant especially with hypertension and obesity. While systolic dysfunction is infrequently seen in childhood chronic KF, systolic strain identified by speckle tracking echocardiography has been frequently identified in dialysis and it can also persist post-transplant. Echocardiogram association with long-term outcomes has not been studied in childhood KF but there are many adult studies demonstrating associations between increased LVM, systolic dysfunction, strain, diastolic dysfunction, and cardiovascular events and mortality. There has been limited study of interventions to improve echocardiogram status. In childhood, improved blood pressure has been associated with better LVM, and conversion from hemodialysis to hemodiafiltration has been associated with better diastolic and systolic function. Whether long-term cardiac outcomes are also improved with these interventions is unclear. Echocardiography is a well-established technique, and regular use in childhood chronic KF seems justified. A case can be made to extend screening to include speckle tracking echocardiography and intradialytic studies in high-risk populations. Further longitudinal studies including these newer echocardiogram modalities, interventions, and long-term outcomes would help clarify recommendations for optimal use as a screening tool.

Nutritional management of the infant with chronic kidney disease stages 2-5 and on dialysis

The nutritional management of children with chronic kidney disease (CKD) is of prime importance in meeting the challenge of maintaining normal growth and development in this population. The objective of this review is to integrate the Pediatric Renal Nutrition Taskforce clinical practice recommendations for children with CKD stages 2-5 and on dialysis, as they relate to the infant from full term birth up to 1 year of age, for healthcare professionals, including dietitians, physicians, and nurses. It addresses nutritional assessment, energy and protein requirements, delivery of the nutritional prescription, and necessary dietary modifications in the case of abnormal serum levels of calcium, phosphate, and potassium. We focus on the particular nutritional needs of infants with CKD for whom dietary recommendations for energy and protein, based on body weight, are higher compared with children over 1 year of age in order to support both linear and brain growth, which are normally maximal in the first 6 months of life. Attention to nutrition during infancy is important given that growth is predominantly nutrition dependent in the infantile phase and the growth of infants is acutely impaired by disruption to their nutritional intake, particularly during the first 6 months. Inadequate nutritional intake can result in the failure to achieve full adult height potential and an increased risk for abnormal neurodevelopment. We strongly suggest that physicians work closely with pediatric renal dietitians to ensure that the infant with CKD receives the best possible nutritional management to optimize their growth and development.

Left ventricular hypertrophy in pediatric patients on maintenance dialysis: a report of the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS)

BACKGROUND

Cardiovascular disease is the leading cause of death in pediatric patients with kidney failure. Left ventricular hypertrophy (LVH) is recognized as the most common cardiovascular abnormality in these patients. There remains a paucity of longitudinal studies evaluating LVH during maintenance dialysis in children. NAPRTCS has collected echocardiographic data of pediatric maintenance dialysis patients since 2013 and is one of the largest registries to assess longitudinal changes in LVH.

METHODS

Patients aged 1-18 years with echocardiographic data and without underlying structural cardiovascular diseases were included. LVH was defined as left ventricular mass index (LVMI, height-indexed) > 95th percentile for age and sex. Univariate and multivariable logistic regression was performed to assess risk factors for LVH at baseline. Generalized estimating equation was used to assess risk factors of changes in LVH during maintenance dialysis.

RESULTS

A total of 518 patients had echocardiographic data available for analysis during time on maintenance dialysis. Of 179 patients with baseline echocardiography (within 30 days of dialysis initiation), 67% had LVH. In multivariable logistic regression adjusted for age, race, and sex, uncontrolled hypertension (OR 9.4, 95% CI 2.8-31) and anemia (OR 2.3, 95% CI 1.0-5.3) were associated with LVH at baseline. Prevalence of LVH remained high at 40-50% during follow-up. Controlled and uncontrolled hypertension as well as phosphorus level were independently associated with increased likelihood of LVH during maintenance dialysis.

CONCLUSIONS

LVH is prevalent in pediatric patients at dialysis initiation and remains prevalent during follow-up. Hypertension is the strongest risk factor for LVH in children on maintenance dialysis. A higher resolution version of the Graphical abstract is available as Supplementary information.

Evaluation of Asymmetric Dimethylarginine Serum Level and Left Ventricular Function by 2D Speckle Tracking Echocardiography in Children on Regular Hemodialysis

Cardiovascular disease is the leading cause of morbidity and mortality in children with chronic kidney disease. Asymmetric dimethylarginine (ADMA) is thought to be related to chronic kidney disease patients' adverse cardiovascular effects. Our study is to assess ADMA concentrations in children on hemodialysis (HD) as a marker of cardiovascular risk and detect the relation to the left ventricular (LV) function by traditional and speckled tracking echo. Forty children with end-stage renal disease on regular HD were enrolled in the study and selected from the nephrology HD unit of Al-Zahraa Hospital, Al-Azhar University. Another group of 40 healthy children matches age and sex with the patient's group as a control. ADMA serum level, traditional echo, and tissue Doppler imaging spackled tracking were performed to assess: LV functions for both groups in the same line with the routine laboratory investigations. Moreover, bioimpedance was assessed after the HD session. Children on regular HD have a significantly higher (ADMA) serum level compared to their controls; the median is (72.5 ng/mL) and (25 ng/mL), respectively (P = 0.001) and a significant increase in high-sensitivity C-reactive protein and the median is (3.6 ng/mL) and (2.5 ng/mL), respectively (P = 0.001). Moreover, conventional echo detects 27 (67.5%) patients out of 40 had an impaired LV function; meanwhile, 33 (82.5%) had a global LV strain (LV GLS) detected by 2D (Speckle echo), a negative correlation between LV ejection fraction with serum (urea, cholesterol, and triglyceride) and a positive correlation between ADMA and LV systolic diameter. LV GLS (Speckle echo) is negatively correlated with LV end-diastolic diameter, LV end-systolic diameter and positively correlated with LV inter ventricular septum in diastole and reduced average systolic velocity (ml). The sensitivity and specificity of (ADMA), high-sensitivity C-reactive protein (hs-CRP), traditional, and Speckle echo for early left ventricular (LV) dysfunction were 92.50, 92, and 67.50, 97 and 67.50, 90.00, and 80.00, 92, respectively. An ADMA emerges as a sensitive and specific marker for early LV dysfunction in children on hemodialysis (HD); drugs targeting ADMA isessential in the future direction after clinical approval, to avoid early LV changes, furthermore (Speckle echo) is superior to the traditional echo for early detection of LV changes in chronic kidney disease (CKD) children.

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.

Prognostic significance of concentric left ventricular hypertrophy at peritoneal dialysis initiation

Background

Concentric left ventricular hypertrophy (cLVH) is a common left ventricular geometric pattern in patients undergoing maintenance dialysis, including peritoneal dialysis (PD). The relationship between cLVH at PD initiation and the prognosis of patients remains unclear, however. This study aimed to investigate the impact of cLVH at PD initiation on patient survival and major adverse cardiovascular events (MACE).

Methods

The retrospective cohort study included 131 patients who underwent echocardiography during the PD initiation period. Based on echocardiographic measurements, cLVH was defined as a condition with increased LV mass index and increased relative wall thickness. The relationship between cLVH and the prognosis was assessed.

Results

Concentric LVH was identified in 29 patients (22%) at PD initiation, and patient survival, MACE-free survival and PD continuation were significantly reduced in the cLVH group compared with the non-cLVH group. In the Cox regression analysis, cLVH was demonstrated as an independent risk factor of mortality (HR [95%CI]: 3.32 [1.13–9.70]) for all patients. For patients over 65 years old, cLVH was significantly associated with mortality and MACE (HR [95%CI]: 3.51 [1.06–11.58] and 2.97 [1.26–7.01], respectively). Serum albumin at PD initiation was independently correlated with cLVH.

Conclusions

In our study, cLVH at PD initiation was independently associated with survival in all patients and with both survival and MACE in elderly patients. Evaluation of LV geometry at PD initiation might therefore help identify high-risk patients. Further studies involving larger numbers of patients are needed to confirm the findings from this study and clarify whether treatment interventions for factors such as nutrition status could ameliorate cLVH and improve patient outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02321-1.

Coronary microcirculation and left ventricular diastolic function: comparison between patients on hemodialysis and peritoneal dialysis

BACKGROUND

End-stage renal disease is considered to influence coronary microcirculation and left ventricular (LV) diastolic function. We investigated whether differences exist in LV diastolic function indices and coronary flow reserve (CFR) between patients on hemodialysis (HD) and peritoneal dialysis (PD).

METHODS

A complete transthoracic echocardiographic study was performed on 21 HD and 22 PD patients and LV diastolic function was evaluated. CFR was estimated using transthoracic Doppler echocardiography on the left anterior descending artery, during high-dose dypiridamole infusion.

RESULTS

HD and PD groups did not differ regarding Doppler-derived diastolic indices, but they significantly differed in the frequency of severe LV hypertrophy (38.1% in HD vs 4.5% in PD group, p = 0.009) and grade II diastolic dysfunction (42.9% in HD vs 4.5% in PD group, p = 0.004). No patient had restrictive filling pattern. There was no difference in the prevalence of arterial hypertension and diabetes mellitus in patients with grade II vs less than grade II dysfunction. Mean CFR was similar in the HD and PD groups (2.25 ± 0.65 vs 2.36 ± 0.76, p = 0.635) and lower in patients with grade II diastolic dysfunction (1.87 ± 0.43 vs 2.44 ± 0.72, p = 0.023) and diabetes (1.70 ± 0.59 vs 2.39 ± 0.68, p = 0.04). LV mass index was negatively associated with CFR (r = - 0.308, p = 0.045).

CONCLUSION

Patients on HD had more advanced diastolic dysfunction compared to PD, independently of the presence of hypertension and diabetes. CFR did not differ between HD and PD patients, but it was significantly lower in diabetics and in patients with more advanced diastolic dysfunction.

Long-term all-cause mortality and cardiovascular outcomes in Scottish children after initiation of renal replacement therapy: a national cohort study

BACKGROUND

Data on long-term outcomes in children who have received renal replacement therapy (RRT) for end-stage renal disease are limited.

METHODS

We studied long-term survival and incidence of fatal and nonfatal cardiovascular disease (CVD) events and determinants of these outcomes in children who initiated RRT between 1961 and 2013 using data from the Scottish Renal Registry (SRR). Linkage to morbidity records was available from 1981.

RESULTS

A total of 477 children of whom 55% were boys, almost 50% had congenital urinary tract disease (CAKUT), 10% received a transplant as the first mode of RRT and almost 60% were over 11 years of age at start of RRT were followed for a median of 17.8 years (interquartile range (IQR) 8.7-26.6 years). Survival was 87.3% (95% confidence interval (CI) 84.0-90.1) at 10 years and 77.6% (95% CI 73.3-81.7) at 20 years. During a median follow-up of 14.96 years (IQR 7.1-22.9), 20.9% of the 381 patients with morbidity data available had an incident of CVD event. Age < 2 years at start of RRT, receiving dialysis rather than a kidney transplant and primary renal disease (PRD) other than CAKUT or glomerulonephritis (GN), were associated with a higher risk of all-cause mortality. Male sex, receiving dialysis rather than a kidney transplant and PRD other than CAKUT or GN, was associated with a higher risk of CVD incidence.

CONCLUSIONS

Mortality and CVD incidence among children receiving RRT are high. PRD and RRT modality were associated with increased risk of both all-cause mortality and CVD incidence.

Cardiac Remodeling in Chronic Kidney Disease

Cardiac remodeling occurs frequently in chronic kidney disease patients and affects quality of life and survival. Current treatment options are highly inadequate. As kidney function declines, numerous metabolic pathways are disturbed. Kidney and heart functions are highly connected by organ crosstalk. Among others, altered volume and pressure status, ischemia, accelerated atherosclerosis and arteriosclerosis, disturbed mineral metabolism, renal anemia, activation of the renin-angiotensin system, uremic toxins, oxidative stress and upregulation of cytokines stress the sensitive interplay between different cardiac cell types. The fatal consequences are left-ventricular hypertrophy, fibrosis and capillary rarefaction, which lead to systolic and/or diastolic left-ventricular failure. Furthermore, fibrosis triggers electric instability and sudden cardiac death. This review focuses on established and potential pathophysiological cardiorenal crosstalk mechanisms that drive uremia-induced senescence and disease progression, including potential known targets and animal models that might help us to better understand the disease and to identify novel therapeutics.

The dietary management of calcium and phosphate in children with CKD stages 2-5 and on dialysis-clinical practice recommendation from the Pediatric Renal Nutrition Taskforce

In children with chronic kidney disease (CKD), optimal control of bone and mineral homeostasis is essential, not only for the prevention of debilitating skeletal complications and achieving adequate growth but also for preventing vascular calcification and cardiovascular disease. Complications of mineral bone disease (MBD) are common and contribute to the high morbidity and mortality seen in children with CKD. Although several studies describe the prevalence of abnormal calcium, phosphate, parathyroid hormone, and vitamin D levels as well as associated clinical and radiological complications and their medical management, little is known about the dietary requirements and management of calcium (Ca) and phosphate (P) in children with CKD. The Pediatric Renal Nutrition Taskforce (PRNT) is an international team of pediatric renal dietitians and pediatric nephrologists, who develop clinical practice recommendations (CPRs) for the nutritional management of various aspects of renal disease management in children. We present CPRs for the dietary intake of Ca and P in children with CKD stages 2-5 and on dialysis (CKD2-5D), describing the common Ca- and P-containing foods, the assessment of dietary Ca and P intake, requirements for Ca and P in healthy children and necessary modifications for children with CKD2-5D, and dietary management of hypo- and hypercalcemia and hyperphosphatemia. The statements have been graded, and statements with a low grade or those that are opinion-based must be carefully considered and adapted to individual patient needs based on the clinical judgment of the treating physician and dietitian. These CPRs will be regularly audited and updated by the PRNT.

Impact of Dialysis Adequacy on Cardiac Function in Pediatric CAPD Patients

Background

Left ventricular hypertrophy is a major cause of morbidity and mortality among patients with chronic renal failure. Uremia-related risk factors play a fundamental role in its occurrence, thus better prognosis and prolonged survival can be attained by successful dialytic therapies.

Objective

To investigate whether dialysis adequacy has a beneficial effect on cardiac structure and function in children receiving continuous ambulatory peritoneal dialysis (CAPD).

Design

Cross-sectional study in the Pediatric Peritoneal Dialysis Unit of a university hospital.

Patients

Eighteen children, aged 13.3 ± 2.8 years, being treated with CAPD, and 20 healthy age- and sex-matched control subjects were enrolled in this study.

Main Outcome Measures

Echocardiographic evaluation was performed in all subjects. Dialysis adequacy indices [weekly urea (Kt/V) and creatinine clearance (TCCr)] were calculated in the dialysis group.

Results

Interventricular septal thickness, left ventricular (LV) posterior wall thickness, LV mass index (LVMI), and LV end systolic and diastolic dimensions were all found to be significantly higher in the CAPD group compared to the control subjects ( p < 0.01). Ejection fraction and fractional shortening of the LV were not significantly different between the two groups. Mean Kt/V was 2.02 ± 0.71 and mean TCCr was 58 ± 33 L/wk/1.73 m2. There were significant negative correlations between dialysis adequacy indices and LV end systolic and diastolic dimensions ( p < 0.05 and p < 0.001). Ejection fraction and fractional shortening were positively correlated with Kt/V ( p < 0.01). Systolic and diastolic blood pressures were positively correlated with LVMI ( r = 0.501 and r = 0.523). Significant inverse correlations between mean arterial pressure and both Kt/V and TCCr ( r = -0.555 and r = -0.520) were detected.

Conclusion

These data clearly document that cardiac structure and function are remarkably influenced by the uremic state and dialysis therapy in pediatric CAPD patients. The close relationships between echocardiographic findings and dialysis adequacy indices suggest that adequate dialysis has a beneficial effect on cardiac function via effective removal of toxic substances.

Effects of changes in adult erythropoietin dosing guidelines on erythropoietin dosing practices, anemia, and blood transfusion in children on hemodialysis: findings from North American Pediatric Renal Trials and Collaborative Studies (NAPRTCS)

BACKGROUND

While adult hemodialysis (HD) patients have increased morbidity with higher target hemoglobin levels, similar findings have not been demonstrated in pediatric patients. We evaluated changes in transfusions, anemia frequency, and erythropoietin (epo) dosing among pediatric HD patients before, during, and after implementation of federal dialysis payment policies regarding epo dosing for adult HD patients.

METHODS

This is a retrospective cohort study of pediatric HD patients enrolled in NAPRTCS. We evaluated need for transfusion, anemia, median hemoglobin, and median epo dose 6 months after starting HD in 3 eras: baseline (2003-2007), implementation (2008-2011), and post implementation (2012-2016). We used multivariate logistic regression models to evaluate potential differences in transfusion across the eras.

RESULTS

Six months after dialysis initiation, 12.6% of patients required transfusion pre-implementation, 17.9% during implementation, and 15.5% post implementation. Anemia occurred in 17.4% of patients pre, 23.5% during, and 23.8% post implementation, with median hemoglobin levels of 11.9 g/dL pre, 11 g/dL during, and 11 g/dL post implementation. Epo use was high across all 3 eras, but epo dosing decreased during and post implementation, despite more anemia during these periods. Odds of transfusion in implementation era compared with pre-implementation was 1.75 (95% CI 1.11-2.77) and odds of transfusion in post implementation era compared with pre was 1.19 (95% CI 0.71-1.98), controlling for age, race, gender, and prior transplant status.

CONCLUSIONS

During and following implementation of adult epo dosing guidelines, transfusion and anemia frequency increased in pediatric HD patients. Ideal target hemoglobin levels for pediatric dialysis patients warrant further study.

Cardiovascular risk factors in children on dialysis: an update

Cardiovascular disease (CVD) is a life-limiting comorbidity in patients with chronic kidney disease (CKD). In childhood, imaging studies have demonstrated early phenotypic characteristics including increases in left ventricular mass, carotid artery intima-media thickness, and pulse wave velocity, which occur even in young children with early stages of CKD. Vascular calcifications are the signature of an advanced phenotype and are mainly found in adolescents and young adults treated with dialysis. Association studies have provided valuable information regarding the significance of a multitude of risk factors in promoting CVD in children with CKD by using intermediate endpoints of measurements of surrogate parameters of CVD. Dialysis aggravates pre-existing risk factors and accelerates the progression of CVD with additional dialysis-related risk factors. Coronary artery calcifications in children and young adults with CKD accumulate in a time-dependent manner on dialysis. Identification of risk factors has led to improved understanding of principal mechanisms of CKD-induced damage to the cardiovascular system. Treatment strategies include assessment and monitoring of individual risk factor load, optimization of treatment of modifiable risk factors, and intensified hemodialysis if early transplantation is not possible.

Perioperative renal transplantation management in small children using adult-sized living or deceased donor kidneys: A single-center experience

Kidney transplantation remains the treatment of choice for children with ESRD. Optimal perioperative management is critical in small recipients of ASK to assure adequate graft perfusion. We present a single-center experience outlining management for patients weighing <20 kg who underwent primary renal transplantation with ASKs between 2007 and 2016. Sixty-three patients met study criteria and underwent 34 living-related, six living-unrelated, and 23 deceased donor kidney transplants. Median age and weight at transplant were 25 months (IQR 18-37 months; range 11 months-6 years) and 11.0 kg (IQR 9.2-14.5 kg; range 7.1-19.5 kg). Eighty-nine percent of patients required vasoactive agents intra-operatively, with twenty patients requiring prolonged vasoactive agents post-operatively. Intra-operatively, patients received 51.9 mL/kg of crystalloid, 27.3 mL/kg of 5% albumin, and 13.6 mL/kg of packed red blood cells. Most (93.7%) patients were extubated on POD#0. Weights peaked on post-operative days three through five. Over a median follow-up of 49 months (IQR 31-86 months; range 0-130 months), four grafts were lost, two due to thrombosis and two secondary to chronic rejection. There was one patient death six months post-transplant due to causes unrelated to transplantation. Graft survival at 1, 5, and 10 years was 98.4%, 96.6%, and 84.2%, respectively. Of surviving allografts, the median 1, 5, and 10 years post-transplant eGFR was 122.9, 90.0, and 59.2 mL/min/1.73 m² as determined by the 2009 Schwartz formula. Renal transplantation in small children using ASKs requires meticulous perioperative management including adequate fluid resuscitation and judicious use of pressors to assure adequate graft perfusion. The use of ASKs from living or deceased donors results in satisfactory short and long-term outcomes.

Improved blood pressure and left ventricular remodelling in children on chronic intermittent haemodialysis: a longitudinal study

OBJECTIVES

We aimed to examine longitudinal changes in left ventricular (LV) structure and function and evaluate factors associated with LV remodelling in children on chronic haemodialysis.

METHODS

Retrospective longitudinal study including all children from the start of chronic haemodialysis with two or more m-mode 2D echocardiograms and tissue Doppler studies. Left ventricular mass (LVM) in g/m^2.7, geometry and LV function were compared at baseline (dialysis start) with follow-up studies at least 6 months following commencement. Left ventricular hypertrophy (LVH) was defined if greater than 95th percentile as per age-specific centiles. We also defined LVH as indexed LV mass index (LVMI) > 51 g/m^2.7 and using LV mass-for-height z-scores greater than the 95th percentile. Biochemical data, interdialytic weight change and blood pressure level were assessed for their association with change in indexed LVM.

RESULTS

Twenty-three of the 32 children < 18 years were included (n = 5, < 5 years) with last follow-up study performed following dialysis after a median (IQR) of 21 (10-34) months. The prevalence of LVH reduced significantly (69.6%, (n = 16/23) vs. 39.1% (n = 9/23), P = 0.002); LV geometry improved (13% concentric and 56.5% eccentric vs. 8.7% and 17.4% respectively) with mean ± SD reduction in indexed LVM (50.8 ± 23.1 g/m^2.7 vs. 38.6 ± 14.7 g/m^2.7, P = 0.002) and LV mass-for-height z-scores (0.67 ± 1.66 vs. - 0.46 ± 1.88, P = 0.002) from baseline to last follow-up respectively. There was no change in systolic function (LV fractional shortening, 37% vs. 38%, P = 0.39) and diastolic function (mean E/E' 10.8 vs. 9.0, P = 0.09). Multiple regression analysis identified improved systolic BP control (β = 0.41, P = 0.04) as an independent predictor for change in indexed LVM.

CONCLUSIONS

LV structure and function can improve in children despite long-term chronic intermittent haemodialysis. Cardiovascular health in this population does not always deteriorate but can be stabilised and indeed improved with optimal blood pressure management.

Ambulatory blood pressures and central blood pressures are associated with cardiovascular morbidity in adolescent and young adult patients receiving chronic hemodialysis

BACKGROUND

Left ventricular hypertrophy (LVH) and arterial stiffness measured by pulse wave velocity (PWV) are independent predictors of cardiovascular (CV) mortality in adults receiving chronic dialysis. Hypertension strongly associates with elevated left ventricular mass index (LVMI) and PWV, with ambulatory blood pressure monitoring (ABPM), and central blood pressure (CBP) superior to office blood pressures (BP) in predicting CV morbidity. Few studies have described associations of office BP, ABPM, and CBP with LVMI and PWV in adolescent and young adult patients receiving hemodialysis (HD).

METHODS

Cross-sectional study of 22 adolescents and young adults receiving chronic HD. Pre- and post-dialysis office BP and CBP using applanation tonometry were obtained. Twenty-four-hour ABPM was obtained midweek post-dialysis. Pre- and post-dialysis carotid-brachial PWV were obtained same day as BP measurements. Annual echocardiograms for standard care were reviewed for LVH.

RESULTS

Pre-dialysis CBP index correlated with LVMI (r = 0.3, p = 0.04) and PWV (r = 0.48, p = 0.02). Hypertensive patients identified by ABPM had worse LVMI; daytime ABPM systolic BP index correlated with LVMI (r = 0.5, p = 0.02). Office BP was not associated with LVMI; only office diastolic BP was associated with PWV (r = 0.46, p = 0.02). There was no correlation of LVMI or PWV with bone health parameters, anemia, interdialytic weight gain, or residual renal function.

CONCLUSIONS

Ambulatory blood pressure monitoring is superior to casual office BP obtained at time of dialysis in delineating cardiovascular morbidity in adolescent and young adult HD patients. CBP is easily performed and correlates with LVMI and PWV in adolescent and young adult HD patients; however, large-scale normative data is needed.

Free Water Transport and Its Association with Cardiovascular Status in Children on Peritoneal Dialysis

Background:Volume overload is one of the most important factors associated with left ventricular hypertrophy (LVH) and cardiovascular disease in chronic peritoneal dialysis (PD) patients. MiniPET is a reliable tool to evaluate free water transport (FWT). In a clinical setting, the significance of FWT has not been evaluated in terms of outcome in children on PD. The objective was to define a FWT value of clinical significance in children on PD, fixing its relationship to left ventricular mass index (LVMI) as a well-known outcome parameter.Methods:MiniPET was performed with 3.86% glucose, 1-h long, to measure FWT in PD patients > 6 years old. An echocardiogram (ECG) was performed within 2 months of the MiniPET. Left ventricular hypertrophy was defined as LVMI ≥ 38.6 g/height^2.7 (95th percentile). Receiver operating characteristic curve (ROC) analysis was used to determine the cut-off value of FWT searching the highest sensitivity and specificity to differentiate patients with normal/abnormal LVMI. A p < 0.05 was considered significant.Results:Forty-six studies were performed on 32 patients, 16 males; mean age 11.59 ± 3.07 years. Mean normalized FWT (nFWT) was 144.4 ± 84.8 mL/m², corresponding to 46.7% of total ultrafiltration. Mean LVMI was 42 ± 11.3 g/m^2.7 with a negative correlation to nFWT (p < 0.01). Eighteen out of 32 patients had LVH. The ROC analysis (nFWT vs LVMI) showed an area under the curve of 0.71 (95% confidence interval [CI], 0.53 - 0.89; p = 0.04), allowing a cut-off nFWT value of 110 mL/m² to be defined, dividing the population into 2 groups of patients according to the LVMI cut-off value of 38,6 g/m^2.7.Conclusions:The nFWT showed an inverse correlation to LVMI. A nFWT value < 110 mL/m² was significantly associated with LVH. The negative relationship observed between nFWT and LVMI, and the cut-off level for nFWT according to the 95th percentile of LVMI, suggest that the regular evaluation of nFWT could become a useful tool in assessing the capacity of PD treatment to keep patients' volume status under control, avoiding cardiovascular impairment.

Cardiovascular Disease in Children and Adolescents With Chronic Kidney Disease

The lifespan of children with advanced chronic kidney disease (CKD), although improved over the past 2 decades, remains low compared with the general pediatric population. Similar to adults with CKD, cardiovascular disease accounts for a majority of deaths in children with CKD because these patients have a high prevalence of traditional and uremia-related risk factors for cardiovascular disease. The cardiovascular alterations that cause these terminal events begin early in pediatric CKD. Initially, these act to maintain hemodynamic homeostasis. However, as the disease progresses, these modifications are unable to sustain cardiovascular function in the long term, leading to left ventricular failure, depressed cardiorespiratory fitness, and sudden death. In this review, we discuss the prevalence of the risk factors associated with cardiovascular disease in pediatric patients with CKD, the pathophysiology that stimulates these changes, the cardiac and vascular adaptations that occur in these patients, and management of the cardiovascular risk in these patients.

Effects of Hemodiafiltration versus Conventional Hemodialysis in Children with ESKD: The HDF, Heart and Height Study

BACKGROUND

Hypertension and cardiovascular disease are common in children undergoing dialysis. Studies suggest that hemodiafiltration (HDF) may reduce cardiovascular mortality in adults, but data for children are scarce.

METHODS

The HDF, Heart and Height study is a nonrandomized observational study comparing outcomes on conventional hemodialysis (HD) versus postdilution online HDF in children. Primary outcome measures were annualized changes in carotid intima-media thickness (cIMT) SD score and height SD score.

RESULTS

We enrolled 190 children from 28 centers; 78 on HD and 55 on HDF completed 1-year follow-up. The groups were comparable for age, dialysis vintage, access type, dialysis frequency, blood flow, and residual renal function. At 1 year, cIMT SD score increased significantly in children on HD but remained static in the HDF cohort. On propensity score analysis, HD was associated with a +0.47 higher annualized cIMT SD score compared with HDF. Height SD score increased in HDF but remained static in HD. Mean arterial pressure SD score increased with HD only. Factors associated with higher cIMT and mean arterial pressure SD-scores were HD group, higher ultrafiltration rate, and higher β2-microglobulin. The HDF cohort had lower β2-microglobulin, parathyroid hormone, and high-sensitivity C-reactive protein at 1 year; fewer headaches, dizziness, or cramps; and shorter postdialysis recovery time.

CONCLUSIONS

HDF is associated with a lack of progression in vascular measures versus progression with HD, as well as an increase in height not seen in the HD cohort. Patient-related outcomes improved among children on HDF correlating with improved BP control and clearances. Confirmation through randomized trials is required.

Early predictors of cardiac dysfunction in Egyptian children with chronic kidney disease

Background:

Cardiovascular morbidity (CVM) is the main etiology of mortality in children and adolescents with chronic kidney disease (CKD). CKD associated cardiovascular mortality is more common in children with diastolic cardiac dysfunction which was considered as an early indicator for death, while increased left ventricular mass (LVM) is a strong independent risk factor for these patients. Vitamin D deficiency was previously studied as one of the risk factors for CVM.

Aim:

The aim of the work was to investigate the relationship between biomarkers of mineral bone disorder including serum 25(OH) Vitamin D3 (25-OH D3), phosphorus and calcium × phosphorus (Ca×Po4) product with diastolic cardiac function and LVM in children and adolescents with CKD.

Subjects and Methods:

This was a cross-sectional observational study. Participants were classified into two groups: Group I including 86 pediatric patients with CKD (stages 4 or 5) and Group II including 40 healthy controls. Group I was subdivided into IA included children with diastolic dysfunction and IB included cases without diastolic dysfunction. 25-OH D3 level was measured by enhanced chemiluminescence method and intact parathyroid hormone (iPTH) by electrochemiluminescence method. Parameters for diastolic function and LVM were assessed by Doppler echocardiography, tissue Doppler imaging, and M-mode echocardiography.

Results:

25-OH D3 level was significantly lower in Group I when compared to Group II. Diastolic dysfunction was present in 48.8% of the studied patients and was significantly associated with increased serum phosphorus and calcium-phosphorus product but not with decreased level of 25-OH D3. There was a significant positive correlation between LVM and iPTH.

Conclusions:

Hyperphosphatemia and high Ca×Po4 product were considered of prognostic value as they predict early diastolic dysfunction and increased LVM in children with CKD.

Cardiovascular risk in children and adolescents with end stage renal disease

OBJECTIVES

To evaluate cardiovascular involvement in children and adolescents with End Stage Renal Disease (ESRD) and to characterize the main risk factors associated with this outcome.

METHODS

Cross-sectional study of 69 children and adolescents at renal transplantation and 33 healthy individuals matched by age and gender. The study outcomes were left ventricular mass z-score (LVMZ) and carotid artery intima-media thickness (CIMT). The potential risk factors considered were age, gender, CKD etiology, use of oral vitamin D and calcium-based phosphate binders, systolic and diastolic blood pressure, body mass index z-score, time since diagnosis, dialysis duration, serum levels of ionic calcium, phosphorus, parathyroid hormone, fibroblast growth factor (FGF 23), uric acid, homocysteine, cholesterol, triglycerides, C-reactive protein (CRP), vitamin D and hemoglobin.

RESULTS

In the multivariate analysis, the factors associated with LVMZ were dialysis duration, age, systolic blood pressure, serum hemoglobin and HDL cholesterol levels. Regarding CIMT, in the multivariate analysis, systolic blood pressure was the only factor associated with the outcome.

CONCLUSION

Children exhibited important cardiovascular involvement at the time of the renal transplantation. Both of the studied outcomes were independently associated with systolic blood pressure. For this reason, controlling blood pressure seems to be the main therapy to minimize cardiovascular involvement in children with ESRD.

Towards cardiovascular risks in children with chronic kidney disease: a prospective cohort study

Background: Children with chronic kidney disease (CKD) are at substantially high risk of morbidity and mortality from cardiovascular disease (CVD). Although this issue has been extensively studied in adults, little is known whether similar associations exist in the paediatric population. We therefore aimed to evaluate the cardiac structure and function in children with CKD, and investigate the factors that contribute to the development of CVD. Methods: A prospective cohort was established following 40 children with CKD treated in the nephrology unit at a high-volume, tertiary, teaching hospital and compared to age- and gender-matched controls of the same number.  We reviewed the patients’ medical records, assessed growth parameters, measured blood pressure, took blood samples, and performed echocardiography. Results: More than half of the CKD patients are hypertensive (N = 22; 55%) and were found to have a higher proportion of increased left ventricular mass index (LVMI) (75.5%; P = 0.001). In contrast, we did not find any significant association between CKD and both valvular calcification & left ventricular (LV) fractional shortening (FS) in children (P = 0.314). Furthermore, high LVMI is found to be correlated well with the following: anaemia, hypertension, CKD duration > one year, hyperparathyroidism, estimated glomerular filtration rate (eGFR) < 15ml/minute/1.73 m2 and death (P < 0.05). Conclusions: Despite the fact that LV systolic function is preserved and valvular calcification is usually absent, left ventricular hypertrophy (LVH) is common in children with CKD. Hypertension, anaemia, hyperparathyroidism, as well as the severity and duration of renal impairment, are amongst the additional risk factors that predispose to LVH. We contribute this study to the growing information of the review articles regarding the association between CKD and CVD in paediatrics.

Evaluation of T-wave alternans in pediatric patients with chronic renal failure

INTRODUCTION

Microvolt T-wave alternans (TWA) is known to be useful in prediction of ischemia and sudden death in high-risk populations and there are no studies in children with chronic renal failure (CRF). Cardiac problems seem to be responsible for an important part of death in children and young adults with CRF. The aim of this study is to evaluate Holter microvolts TWA measurements in children with CRF comparing to the control group.

METHODS

This prospective study included 40 patients with CRF and 48 healthy controls. The history, echocardiography and microvolt TWA values based on 24-hour ECG recordings of the patients were evaluated. Analysis of microvolt TWA was considered on the basis of three leads (V5, V1 and AVF).

RESULTS

Compared with the controls, the mean systolic and diastolic blood pressure values and average heart rates were significantly higher in the children with CRF (p = 0.001 and p = 0.026, respectively). Also, the values of left ventricular internal dimensions at end diastole and end-diastolic volume were significantly higher in CRF group (p = 0.01 and p = 0.049, respectively) and couplet ventricular extrasystole was detected in 2 patients with CRF. Consequently, all TWA values in three leads were increased in CRF group than the control group but the only increase in V5 lead was statistically significant (p = 0.028).

CONCLUSIONS

This study has demonstrated that microvolt TWA values increased in pediatric patients with CRF. TWA might be used for early risk assessment in pediatric patients with CRF in the future.

The first hour refill index: a promising marker of volume overload in children and young adults on chronic hemodialysis

BACKGROUND

Volume overload is a known risk factor for cardiovascular complications in children on hemodialysis (HD), but a measurable index of volume overload is still lacking.

METHODS

We propose a novel index of pre-HD volume overload based on blood volume (BV) monitoring, the first hour refill index (RI), calculated as the ratio between the ultrafiltration rate indexed for body weight during the first HD hour and the percent BV change at the first hour of the treatment. This parameter was retrospectively calculated in 121 sessions in 11 oligoanuric children and young adults on chronic HD, with median age 14.3 years (range 5.4-22.4), and its association with left-ventricular mass index, pre-HD blood pressure, and number of antihypertensive medications was evaluated.

RESULTS

The median RI was 2.07 ml/kg/h/%. There was a significant correlation between RI and median LVMI (r 0.66, p = 0.028), which was 53.4 g/m^2.7 (45.7-64) in patients with a median RI > 2, and 36.6 g/m^2.7 (24.9-47) in those with a median RI < 2 ml/kg/h/% (p = 0.01). The number of antihypertensive drugs per patient was significantly higher in patients with a RI > 2 than in those with a RI < 2 ml/kg/h/% (three vs one per patient; p = 0.02) while blood pressure was not significantly different between the two groups.

CONCLUSIONS

The ratio between the ultrafiltration rate per body weight and the BV change during the first hour of a HD session could be a promising index of refill capacity and pre-HD volume overload in children and young adults on chronic HD.

Factors associated with reduction of left ventricular mass in children on peritoneal dialysis

AIM

This study aimed to investigate sensitive factors involved in left ventricular mass reduction in children with end-stage renal disease (ESRD) undergoing peritoneal dialysis.

METHODS

Thirty-five subjects on peritoneal dialysis were enrolled. Two successive echocardiographic and clinical data for each subject were obtained. Blood pressure and left ventricular mass index (LVMI) were indexed through a division with the normal 95^th percentile value. Differences in numeric data between two datasets were calculated.

RESULTS

The mean age was 12.9 ± 4.6 years. Predictors of left ventricular hypertrophy and its persistence were systolic blood pressure index (P = 0.019 and P = 0.046) and E' velocity (P = 0.035 and P = 0.031) in univariate analysis. However, differences in these predictors between the datasets were not related to the change in indexed LVMI. Reduction in indexed LVMI was correlated to a reduction of indexed left atrial volume (R = 0.638, P = 0.001), trans-mitral A velocity (R = 0.443, P = 0.011), and serum blood urea nitrogen level (R = 0.372, P = 0.028) and an elevation of haemoglobin level (R = -0.374, P = 0.027).

CONCLUSION

The extent of circulating volume expansion is potentially the main predictive factor for change of LVMI, because the volume dependent diastolic functional variables correlate to the change of LVMI. Further study with a large number of ESRD children including a group under fluid volume control is needed to investigate the role of volume expansion on the change of LVMI.

A comprehensive characterization of myocardial and vascular phenotype in pediatric chronic kidney disease using cardiovascular magnetic resonance imaging

BACKGROUND

Children with chronic kidney disease (CKD) have increased cardiovascular mortality. Identifying high-risk children who may benefit from further therapeutic intervention is difficult as cardiovascular abnormalities are subtle. Although transthoracic echocardiography may be used to detect sub-clinical abnormalities, it has well-known problems with reproducibility that limit its ability to accurately detect these changes. Cardiovascular magnetic resonance (CMR) is the reference standard method for assessing blood flow, cardiac structure and function. Furthermore, recent innovations enable the assessment of radial and longitudinal myocardial velocity, such that detection of sub-clinical changes is now possible. Thus, CMR may be ideal for cardiovascular assessment in pediatric CKD. This study aims to comprehensively assess cardiovascular function in pediatric CKD using CMR and determine its relationship with CKD severity.

METHODS

A total of 120 children (40 mild, 40 moderate, 20 severe pre-dialysis CKD subjects and 20 healthy controls) underwent CMR with non-invasive blood pressure (BP) measurements. Cardiovascular parameters measured included systemic vascular resistance (SVR), total arterial compliance (TAC), left ventricular (LV) structure, ejection fraction (EF), cardiac timings, radial and longitudinal systolic and diastolic myocardial velocities. Between group comparisons and regression modelling were used to identify abnormalities in CKD and determine the effects of renal severity on myocardial function.

RESULTS

The elevation in mean BP in CKD was accompanied by significantly increased afterload (SVR), without evidence of arterial stiffness (TAC) or increased fluid overload. Left ventricular volumes and global function were not abnormal in CKD. However, there was evidence of LV remodelling, prolongation of isovolumic relaxation time and reduced systolic and diastolic myocardial velocities.

CONCLUSION

Abnormal cardiovascular function is evident in pre-dialysis pediatric CKD. Novel CMR biomarkers may be useful for the detection of subtle abnormalities in this population. Further studies are needed to determine to prognostic value of these biomarkers.

Darbepoetin Alfa in Young Infants With Renal Failure: Single Center Experience, a Case Series and Review of the Literature

Background: Anemia treatment in infants with advanced or chronic kidney disease (CKD) represents an important challenge to nephrologists. The use of darbepoetin alfa, a novel erythropoiesis stimulating agent, has largely replaced recombinant human erythropoietin in older children and in adults with CKD. However, studies reporting the use of darbepoetin alfa in infants below 1 year of age are rare. Case presentation: We report the data of three infants with advanced stage kidney failure, aged 1, 4, and 7 months, who were treated with darbepoetin alfa and followed for 18-41 months. Hemoglobin levels increased in all three patients, reaching the target levels of 10.7-12 g/dl by 11, 19, and 22 weeks respectively, without any documented adverse effects. Patients younger than 1 year of age required a larger darbepoetin alfa dosage (ranged from 1.2 to 2.9 μg/kg per month) as compared to older children. A review of the literature found only three studies using darbepoetin alfa successfully in such young infants, with similar dosage and clinical success. Conclusion: In these three patients with advanced kidney disease, darbepoetin alfa was effective in correcting anemia with no observed side effects. It reinforces its potential use in very young patients with advanced CKD.

Hypertension and improved left ventricular mass index in children after renal transplantation

This study was conducted to evaluate the changes in BP and LVH after the transplantation and to evaluate the effect of BP changes in LVH. Forty-three pediatric renal transplant patients, with a mean age of 16.99 ± 3.88 years, were enrolled in this study. Twenty-three (53.5%) of the patients were male. Medical records for pretransplantation period (closest to the time of transplantation) and for post-transplantation period (9-12 months after transplantation) were reviewed. All the patients had BP measurements and echocardiographic evaluation in pre- and post-transplantation period. Hypertension was defined as an average systolic and/or diastolic BP that is ≥95th percentile for sex, age, and height. Although the number of patients with hypertension increased from 30 (69.76%) to 35 (81.4%), the number of patients with LVH decreased from 19 (44.1%) to 9 (20.9%) after the transplantation. Although the only significant difference in BP measurements was between the mean Z scores of 24 hour and nighttime mean DBP before and after the transplantation; the mean LVMI, and the prevalence of LVH was significantly lower after the transplantation. There was no significant correlation between the LVMI and the BP measurements. Even though hypertension may persist, there is significant improvement in LVH after renal transplantation.

Effect of high-dose oral cholecalciferol on cardiac mechanics in children with chronic kidney disease

Cardiovascular factors are an important cause of mortality in chronic kidney disease, and vitamin-D deficiency is common in this patient population. Therefore, we aimed to investigate the effect of oral cholecalciferol on cardiac mechanics in children with chronic kidney disease. A total of 41 children with chronic kidney disease - the patient group - and 24 healthy subjects - the control group - free of any underlying cardiac or renal disease with low 25-hydroxyvitamin-D3 levels were evaluated by conventional tissue Doppler imaging and two-dimensional speckle-tracking echocardiography, both at baseline and following Stoss vitamin-D supplementation. Left ventricular strain and strain rate values were compared between the study groups. Initial longitudinal and radial strain as well as strain rate values of the left ventricle were significantly lower in patients. After vitamin-D supplementation, these improved significantly in patients, whereas no significant change was observed in the control group. Our study showed that, although conventional and tissue Doppler imaging methods could not determine any effect, two-dimensional speckle-tracking echocardiography revealed the favourable effects of high-dose cholecalciferol on cardiac mechanics, implying the importance of vitamin-D supplementation in children with chronic kidney disease.

Lung ultrasound: a novel technique for detecting fluid overload in children on dialysis

Background

Optimizing the target weight of infants and children on dialysis remains an important clinical challenge. The use of ultrasound to detect fluid overload in adult patients on dialysis is receiving growing attention. We hypothesized that fluid overload can be quantified in infants and children receiving dialysis using lung ultrasound.

Methods

In this prospective observational study, infants and children receiving dialysis for end-stage renal disease (ESRD) or acute kidney injury (AKI) in a regional paediatric nephrology centre were eligible. Lung ultrasound examinations were performed during in-centre dialysis, on home visits or in an outpatient clinic. Fluid overload was assessed by quantifying B-lines on ultrasound and compared with proportional (%) increase in patient weight from the target weight.

Results

A total of 142 ultrasound assessments were performed in 23 children. In children with AKI, median B-line score reduced from 5 (range 0-22) at presentation to 1.5 (0-4) at recovery (P = 0.04) with concurrent improvement in fluid overload judged by weight from 7.2 (-1.9 to 15.2)% to 0%. A linear correlation between lung ultrasound B-line score and fluid overload judged by weight was observed in children with AKI (r = 0.83) and ESRD (r = 0.61). Inter-observer variability was acceptable.

Conclusions

Lung ultrasound is a practical and sensitive method of quantifying subclinical fluid overload in infants and children on dialysis. Interventional studies to determine the benefits of using lung ultrasound to optimize the target weight for children with ESRD are merited.

Extrarenal effects of FGF23

Chronic kidney disease (CKD) is associated with an increased risk of cardiovascular mortality, infections, and impaired cognitive function. It is characterized by excessively increased levels of the phosphaturic hormone fibroblast growth factor 23 (FGF23) and a deficiency of its co-receptor Klotho. Despite the important physiological effect of FGF23 in maintaining phosphate homeostasis, there is increasing evidence that higher FGF23 levels are a risk factor for mortality and cardiovascular disease. FGF23 directly induces left ventricular hypertrophy via activation of the FGF receptor 4/calcineurin/nuclear factor of activated T cells signaling pathway. By contrast, the impact of FGF23 on endothelial function and the development of atherosclerosis are poorly understood. The results of recent experimental studies indicate that FGF23 directly impacts on hippocampal neurons and may thereby impair learning and memory function in CKD patients. Finally, it has been shown that FGF23 interferes with the immune system by directly acting on polymorphonuclear leukocytes and macrophages. In this review, we discuss recent data from clinical and experimental studies on the extrarenal effects of FGF23 with respect to the cardiovascular, central nervous, and immune systems.

Left Ventricular Hypertrophy in Pediatric Hypertension: A Mini Review

Adults with arterial hypertension (HTN) have stroke, myocardial infarction, end-stage renal disease (ESRD), or die at higher rates than those without. In children, HTN leads to target organ damage, which includes kidney, brain, eye, blood vessels, and heart, which precedes "hard outcomes" observed in adults. Left ventricular hypertrophy (LVH) or an anatomic and pathologic increase in left ventricular mass (LVM) in response to the HTN is a pediatric surrogate marker for HTN-induced morbidity and mortality in adults. This mini review discusses current definitions, clinically relevant methods of LVM measurements and normalization methods, its epidemiology, management, and issue of reversibility in children with HTN. Pediatric definition of LVH and abnormal LVM is not uniformed. With multiple definitions, prevalence of pediatric HTN-induced LVH is difficult to ascertain. In addition while in adults cardiac magnetic resonance imaging is considered "the gold standard" for LVM and LVH determination, pediatric data are limited to "special populations": ESRD, transplant, and obese children. We summarize available data on pediatric LVH treatment and reversibility and offer future directions in addressing LVH in children with HTN.

Comparison of reticulocyte hemoglobin equivalent with traditional markers of iron and erythropoiesis in pediatric dialysis

BACKGROUND

Anemia is a major complication for patients on chronic dialysis. Erythropoietin is effective if iron is available, however unnecessary iron supplementation results in iron overload. Reticulocyte hemoglobin equivalent (Ret-He) may be useful for assessing iron status.

METHODS

A national retrospective cohort study including all children on chronic dialysis in New Zealand between 2007 and 2013, pairing Ret-He with demographic information, anemia indices, and markers of iron status.

RESULTS

In 606 observations, we found a modest relationship between Ret-He and transferrin saturation (TSAT) (r = 0.34, p < 0.001) and a poor correlation between Ret-He and ferritin (r = 0.09, p = 0.04). There was a negative correlation between ferritin and hemoglobin (r = -0.14, p = 0.002), a weak positive correlation between TSAT and hemoglobin (r = 0.12, p = 0.007), and a modest positive correlation between Ret-He and hemoglobin (r = 0.22, p < 0.001). The diagnostic performance of Ret-He to detect absolute iron deficiency (cut-off value 28.9 pg, sensitivity 90 %, specificity 75 %, AUC 0.87) was good.

CONCLUSIONS

Ret-He is a more relevant marker of iron status than ferritin and TSAT. This supports prospectively testing Ret-He to distinguish between iron deficiency and suboptimal erythropoietin dosing as competing causes for anemia. Ferritin is an unhelpful biomarker of iron deficiency in this setting.

Left Ventricular Mass Indexing in Infants, Children, and Adolescents: A Simplified Approach for the Identification of Left Ventricular Hypertrophy in Clinical Practice

OBJECTIVE

To determine a simplified method to identify presence of left ventricular hypertrophy (LVH) in pediatric populations because the relationship between heart growth and body growth in children has made indexing difficult for younger ages.

STUDY DESIGN

Healthy children (n = 400; 52% boys, 0-18 years of age) from 2 different European hospitals were studied to derive a simplified formula. Left ventricular mass (LVM) was calculated according to the Devereux formula. The derived approach to index LVM was tested on a validation cohort of 130 healthy children from a different hospital center.

RESULTS

There was a strong nonlinear correlation between height and LVM. LVM was best related to height to a power of 2.16 with a correction factor of 0.09. Analysis of residuals for LVM/[(height(2.16)) + 0.09] showed an homoscedastic distribution in both sexes throughout the entire height range. A partition value of 45 g/m(2.16) was defined as the upper normal limit for LVM index. As opposed to formula suggested by current guidelines (ie, LVM/height(2.7)) when applying the proposed approach in the validation cohort of 130 healthy participants, no false positives for LVH were found (0% vs 8%; P < .01).

CONCLUSIONS

Our data support the possibility to have a single partition (ie, 45 g/m(2.16)) value across the whole pediatric age range to identify LVH, without the time-consuming need of computing specific percentiles for height and sex.

Effect of cholecalciferol on local arterial stiffness and endothelial dysfunction in children with chronic kidney disease

BACKGROUND

As cardiovascular factors are the leading cause of mortality in chronic kidney disease (CKD) and as vitamin D deficiency is prevalent in this population, we aimed to examine the effect of oral cholecalciferol on cardiac parameters and biomarkers for endothelial cell activation in children with CKD.

METHODS

Forty-one children with CKD and 24 healthy subjects free of any underlying cardiac or renal disease with low 25-hydroxyvitamin D3 (25OHD) levels were evaluated using echocardiography basally and following Stoss vitamin D supplementation. The local vascular stiffness and endothelial dysfunction markers were compared among the groups.

RESULTS

Initial flow-mediated dilatation (FMD) measurements were lower and local arterial stiffness was significantly higher in patients. After vitamin D supplementation, these improved significantly in patients, while no significant change was observed for the healthy group. Homocysteine showed inverse correlation with baseline vitamin D level in CKD children and von Willebrand factor emerged as an independent risk factor for FMD impairment.

CONCLUSIONS

Our interventional study revealed the favorable effects of high-dose cholecalciferol on cardiovascular and endothelial parameters, implying the importance of vitamin D supplementation in children with CKD.

Echocardiographic assessment of right ventricular functions in nondiabetic normotensive hemodialysis patients

PURPOSE

Heart is affected structurally and functionally in end-stage renal disease (ESRD). However, the data available about adverse effects of ESRD on right ventricle (RV) is scarce. We aimed to evaluate echocardiographic parameters of RV in nondiabetic, normotensive patients with ESRD undergoing hemodialysis (HD).

METHODS

A total of 45 (24 women; mean age 52.4 ± 12.4 years) consecutive nondiabetic, normotensive patients with ESRD undergoing HD and 39 healthy age and sex-matched control subjects (22 women; mean age 50.3 ± 6.6 years) were enrolled in the study. M-mode and two dimensional images, color, pulsed and continuous wave Doppler, and tissue Doppler measurements were acquired from all subjects. Echocardiographic evaluation was performed in the days between HD dates of the patients.

RESULTS

RV fractional area change, tricuspid annular plane systolic excursion, tricuspid E velocity, E/A ratio, tricuspid annular E´ velocity, and E´/A´ ratio were lower in patients than controls (p < 0.001, p = 0.003, p = 0.007, p = 0.005, p < 0.001, and p = 0.034, respectively). However, RV diastolic area, RV myocardial performance index, E/E´ ratio, and mean and systolic pulmonary artery pressure were higher in patients than controls (p < 0.001, p = 0.007, p = 0.005, p < 0.001, p = 0.006, respectively).

CONCLUSIONS

RV systolic and diastolic functions of nondiabetic, normotensive HD patients are deteriorated as compared to healthy controls.

Children with chronic renal disease undergoing dialysis or conservative treatment--differences in structural and functional echocardiographic parameters

Cardiac disease frequently occurs in children with chronic kidney disease (CKD) undergoing dialysis (DI), but it is not well studied in patients undergoing conservative treatment (CT). The aim of our study was to use echocardiography to analyze and compare the cardiac involvement of children with CKD undergoing DI or CT.

METHODS

Seventy-one children with CKD were included; 41 undergoing DI and 30 undergoing CT. There were 33 controls. Measurements of arterial pressure and structural and functional echocardiographic variables were obtained; the children were followed up for 18 months. Tests of comparison and multiple regression were used; significant if P < 0.05.

RESULTS

Arterial hypertension (AH) was present in 37 of 71 (52%) children with CKD: 27 (65.8%) in DI and 10 (33.3%) in CT (X2 = 8.7; P = 0.003). An abnormal left ventricular geometric pattern was present in 37/41 (90.3%) undergoing DI, 33 had left ventricular hypertrophy (LVH), and in 14/30 (46.7%) undergoing CT, 5 had LVH. Ejection fraction was normal in all groups; diastolic function alteration (DFA) occurred in 28/41 (68.3%) children on DI and in 10/30 (33.3%) on CT (X2 = 9.2; P = 0.002). For children with CKD, DI (P = 0.002) and hypertension (P = 0.04) were associated with LVH; among those on DI, only AH was associated with LVH (P = 0.02). During the follow-up, 18 (43.9%) children undergoing DI had at least one cardiovascular event.

CONCLUSION

Children with CKD undergoing CT had less cardiac involvement than those undergoing DI. LVH was associated with DI and AH in all children with CKD and with AH in those on DI.

Interdialytic weight gain in oligoanuric children and adolescents on chronic hemodialysis

BACKGROUND

Little is known about the clinical impact of interdialytic weight gain (IDWG) on oligoanuric children undergoing chronic hemodialysis (HD).

METHODS

We retrospectively assessed IDWG, left ventricular mass index (LVMI) and its changes (ΔLVMI), pre-HD systolic and diastolic blood pressure (DBP), residual urine output, Kt/V, the frequency of intradialytic symptoms, normalized protein catabolic rate, and the 3-month change in the dry weight of 16 hemodialyzed oligoanuric patients with a median age of 14.8 years (range 5.0-17.9).

RESULTS

There was a significant correlation between IDWG and median LVMI (r 0.55, p = 0.026), which was 27.3 g/m(2.7) (22.5-37.6) in the patients with a median IDWG of <4 %, and 44.3 g/m(2.7) (28.2-68.7) in those with a median IDWG of >4 % (p = 0.003). None of the four patients with an IDWG of <4 % showed left ventricular hypertrophy, compared with 10 of the 12 patients (83.3 %) with an IDWG of >4 % (p = 0.003); the former also had a better median ΔLVMI (-33.5 % vs -13.0 %; p = 0.02) and a lower median DBP sds (0.24 vs 1.72, p = 0.04).

CONCLUSIONS

There is a significant correlation between IDWG and LVMI in pediatric oligoanuric patients on chronic HD: those with an IDWG of >4 % are at a higher risk of left ventricular hypertrophy.

44-h ambulatory blood pressure monitoring: revealing the true burden of hypertension in pediatric hemodialysis patients

BACKGROUND

The blood pressure (BP) burden is high in pediatric hemodialysis (HD) patients and adversely affects prognosis. The aim of this study was to examine whether 44-h ambulatory BP monitoring (ABPM) provides additional relevant BP data compared with 24-h ABPM.

METHODS

ABPM was initiated at the end of the mid-week dialysis run in 13 stable pediatric HD patients and continued until the next run for 44 h. Day 1 was defined as the initial 24-h ABPM and Day 2 as the time period after that until the next dialysis run. All patients had an echocardiogram to calculate the left ventricular mass index (LVMI).

RESULTS

A higher percentage of patients were diagnosed with hypertension from the 44-h ABPM than from the 24-h ABPM. All BP indexes and loads (except nighttime diastolic load) were significantly higher on Day 2 than on Day 1. Patients with BP loads of ≥ 25 % on 44-h ABPM had significantly higher LVMI than those patients with normal BP loads. No such association was found with 24-h ABPM and LVMI. Higher interdialytic weight gain was associated with higher Day-2 nighttime systolic BP load.

CONCLUSIONS

The 44-h ABPM provides more information than the 24-h ABPM in terms of diagnosing and assessing the true burden of hypertension in pediatric HD patients. Elevated BP loads from 44-h ABPM correlate with a higher LVMI on the echocardiogram.

Assessment and management of hypertension in patients on dialysis

Hypertension is common, difficult to diagnose, and poorly controlled among patients with ESRD. However, controversy surrounds the diagnosis and treatment of hypertension. Here, we describe the diagnosis, epidemiology, and management of hypertension in dialysis patients, and examine the data sparking debate over appropriate methods for diagnosing and treating hypertension. Furthermore, we consider the issues uniquely related to hypertension in pediatric dialysis patients. Future clinical trials designed to clarify the controversial results discussed here should lead to the implementation of diagnostic and therapeutic techniques that improve long-term cardiovascular outcomes in patients with ESRD.

Are endothelial microparticles early markers of pulmonary hypertension?

OBJECTIVE

To find out the relation between endothelial microparticles (EMPs), pulmonary arterial stiffness and thickness of pulmonary artery intima media to determine the prognosis of Eisenmenger syndrome and their correlation with echocardiographic and hemodynamic parameters.

METHODS

Sixteen patients with Eisenmenger syndrome and 37 control patients were included. Electron microparticles levels, angiographic and echocardiographic findings were compared.

RESULTS

Thickness of pulmonary arterial intima media and systolic and diastolic diameters of pulmonary artery were found significant in the patient group. CD144 and CD146 EMP values of patient group were statistically high. However, there was not any significant difference in pulmonary arterial strain, elasticity and stiffness. Positive significant relationship was found between pulmonary artery intima media thickness and CD144 in patient group. But there was not any significance between CD 146 and pulmonary artery intimamedia thickness.

CONCLUSIONS

Invasive methods remain as the gold standard for pulmonary hypertension diagnosis, follow-up and treatment, but it is risky and can even be fatal. Our study showed that EMPs, thickness of pulmonary artery intima media and pulmonary stiffness could be novel noninvasive modalities for the follow-up pulmonary hypertensive patients.