Limitations of U25 CKiD and CKD-EPI eGFR formulae in patients 2-20 years of age with measured GFR > 60 mL/min/1.73 m2-a cross-sectional study.

BACKGROUND: When applying Pierce U25 formula for estimating glomerular filtration rate (eGFR), we observed a higher proportion of eGFR < 90 mL/min/1.73 m2 (chronic kidney disease (CKD) stage 2). We compared agreement and accuracy of the Pierce U25 (ages 2-25), Pottel (ages 2-100), and CKD-EPI (ages 18-100) formulae to GFR measurements. METHODS: Post hoc analysis of the three eGFRs compared to 367 99m technetium-diethylene-triamine penta-acetic acid (99Tc DTPA) GFR measurements (240 patients) using 3 sampling points and Brockner/Mørtensen correction (body surface area calculation based on ideal weight) on simultaneous serum creatinine and cystatin C measurements. RESULTS: Overall, the U25 formula performed well with a Spearman r of 0.8102 (95% confidence interval 0.7706 to 0.8435, p < 0.0001) while diagnostic accuracy was low in patients with normal mGFR. The U25 formula reclassified 29.5% of patients with normal mGFR as CKD stage 2; whereas the average of the modified Schwartz formula based on serum creatinine and the Filler formula based on cystatin C, only over-diagnosed CKD stage 2 in 8.5%, 24.5% within 10% and 62.7% within 30%. We therefore combined both. The average Schwartz/Filler eGFR had 36.5% of results within 10%, 84.7% within 30%, and normal mGFR accuracy was 26.8%, 63.9% for 10% and 30%, respectively, outperforming the CKD-EPI and Pottel formulae. CONCLUSIONS: The Pierce U25 formula results correlated well with mGFR < 75 mL/min/1.73 m2. Over the entire GFR range, accuracy was better for patients with a higher mGFR, when averaging the combined Schwartz/Filler formulae. More work is needed to prospectively confirm our findings in other centers.

Kt/V or Bicarbonate: What Is More Important for Growth in Pediatric Peritoneal Dialysis Patients?

INTRODUCTION: Growth retardation is a common problem in pediatric patients with chronic kidney disease. It is unknown if the growth of children on peritoneal dialysis (PD) can be augmented by more dialysis. METHODS: We studied the effect of various peritoneal adequacy parameters on delta height standard deviation scores (SDSs) and growth velocity z-scores in 53 children (27 males) on PD, who underwent 2 longitudinal adequacy tests at 9-month intervals. None of the patients were on growth hormone. Intraperitoneal pressure and standard KDOQI guidelines were compared to the outcome measures delta height SDS and height velocity z-scores, using univariate and multivariate tests. RESULTS: At the time of the second PD adequacy test, their mean age was 9.2 ± 5.3 years; mean fill volume was 961 ± 254 mL/m2; and median total infused dialysate volume was 5.26 L/m2/day (range 2.03-15.32 L). The median total weekly Kt/V was 3.79 (range 0.9-9.5), and the median total creatinine clearance was 56.6 (range 7.6-133.48) L/week, higher than previous pediatric studies. The delta height SDS was a median of -0.12 (range -2 to +3.95)/year. The mean height velocity z-score was -1.6 ± 4.0. The only relationships discovered were between the delta height SDS and age, bicarbonate, and intraperitoneal pressure, but not for Kt/V or creatinine clearance. CONCLUSION: Our findings highlight the importance of normalization of bicarbonate concentrations to improve height z-score.

Translation and validation of the STARx questionnaire in transitioning Chinese adolescents and young adults with chronic health conditions.

BACKGROUND: Adolescent/young adults (AYAs) with chronic conditions must undergo healthcare transition (HCT) preparation until their mid-twenties. Valid HCT readiness measures are lacking in China. METHODS: The present study translated, back-translated, and adapted the Self-Management and Transition to Adulthood with Rx = Treatment (STARx) Questionnaire. We examined the psychometric properties of this tool in a relatively large in-patient sample of AYAs with various chronic health conditions at a Chinese tertiary general hospital. RESULTS: We enrolled 624 AYAs aged 10-25 years (19.66 ±â€¯3.64) with various chronic health conditions. The Chinese version of the STARx Questionnaire demonstrated excellent internal consistency (Cronbach's alpha = 0.83) and reliability with a two-week test-retest (ICC = 0.88, p < .001). Furthermore, the Chinese version revealed a three-factor structure (self-management, disease knowledge, and provider communication) consistent with the revised English version of the STARx Questionnaire. In terms of discriminant validity, the total score of the Chinese STARx Questionnaire showed a significant positive correlation with age but no gender differences were found. In terms of predictive validity, the Chinese STARx Questionnaire was significantly correlated with shorter length of hospitalization and higher frequency of emergency room visit, but the correlations became insignificant after controlling for age. CONCLUSIONS: The results suggest that the Chinese version of the STARx Questionnaire is a robust HCT readiness tool in AYAs with chronic conditions and clinicians may find it useful to develop individualized interventions.

The self-management and transition manual "ALL YOU NEED IS LOVE" for adolescents with chronic kidney disease.

PURPOSE: To examine the effects of "ALL YOU NEED IS LOVE", a novel six-week, self-directed patient education manual designed to improve chronic kidney disease knowledge/self-management, health care transition readiness, self-advocacy, and mindfulness skills among adolescents with chronic kidney disease. DESIGN AND METHODS: We enrolled 49 adolescents aged 11-17 years (mean age 14.7 ± 1.9; 53.1% males) from a university hospital kidney center who had CKD stages 3 and greater, who were randomly assigned into the "ALL YOU NEED IS LOVE" patient education only group (n = 31) or the "ALL YOU NEED IS LOVE" patient education plus mindfulness training group (n = 18). Participants completed Qualtrics surveys at baseline, post-intervention, and three-month follow-up. The survey included measures of outcome variables (i.e., self-management/transition readiness, patient self-advocacy, and mindfulness), and an additional demographic questionnaire was included in the baseline survey. Multilevel model analyses were used to examine the effects of group and time on the outcome variables. RESULTS: Multilevel model analyses showed an overall significant time effect across all outcome variables in both groups. However, the group effects were not statistically significant across the outcome variables. CONCLUSIONS: Both interventions significantly increased participants' self-management/HCT readiness, self-advocacy, and mindfulness over time. Mindfulness training may not bring additional benefits to the "ALL YOU NEED IS LOVE" education manual. PRACTICE IMPLICATIONS: Pediatric nurses and clinicians may utilize the self-directed "ALL YOU NEED IS LOVE" manual to increase self-management/transition readiness, self-advocacy, and mindfulness among adolescents with chronic kidney disease.

Trends and Disparities in Health Care Transition Preparation from 2016 to 2019: Findings from the US National Survey of Children's Health.

OBJECTIVES: To evaluate national trends in health care transition preparation over a 4-year period using the National Survey of Children's Health (NSCH) and to identify and examine disparities in receipt of health care transition preparation over the study period. STUDY DESIGN: Data from the NSCH, an annual serial cross-sectional survey conducted from 2016 to 2019, were examined. Caregivers answered questions regarding one of their children within each of a random sample of households across the US. The primary analysis examined trends in health care transition preparation based on the year of survey completion. A secondary analysis examined the associations of race/ethnicity, primary household language, insurance type, and children with special health care needs (CSHCN) with receipt of health care transition preparation. RESULTS: We included data from 54 434 youths (20 708 in 2016, 8909 in 2017, 12 587 in 2018, and 12 230 in 2019) aged 12-17 years whose caregivers completed the NSCH between 2016 and 2019. The sample was weighted to be nationally representative based on weights provided by the NSCH. The proportion of youths receiving necessary health care transition preparation increased over the study period, from 14.8% in 2016 to 20.5% in 2019 (P < .001). Multivariable logistic regression demonstrated increased odds of receiving health care transition preparation in 2018 and 2019, as well as for White non-Hispanic youths, those with English or Spanish as a primary household language, those with private insurance, and CSHCN. CONCLUSIONS: Although the proportion of youths receiving health care transition preparation has increased since 2016, the need for ongoing improvement and elimination of disparities in health care transition preparation remains.

Novel Renal Autologous Cell Therapy for Type 2 Diabetes Mellitus Chronic Diabetic Kidney Disease: Clinical Trial Design.

BACKGROUND: Cell therapies explore unmet clinical needs of patients with chronic kidney disease with the potential to alter the pathway toward end-stage kidney disease. We describe the design and baseline patient characteristics of a phase II multicenter clinical trial utilizing the novel renal autologous cell therapy (REACT), by direct kidney parenchymal injection via the percutaneous approach in adults with type 2 diabetic kidney disease (T2DKD), to delay or potentially avoid renal replacement therapy. DESIGN: The study conducted a prospective, multicenter, randomized control, open-label, phase II clinical trial between an active treatment group (ATG) receiving REACT from the beginning of the trial and a contemporaneous deferred treatment group (DTG) receiving standard of care for 12 months before crossing over to receive REACT. OBJECTIVES: The objective of this study was to establish the safety and efficacy of 2 REACT injections with computed tomography guidance, into the renal cortex of patients with T2DKD administered 6 months apart, and to compare the longitudinal change in renal function between the ATG and the DTG. SETTING: This was a multicenter study conducted in major US hospitals. PATIENTS: We enrolled eighty-three adult patients with T2DKD, who have estimated glomerular filtration rates (eGFRs) between 20 and 50 mL/min/1.73 m2. METHODS: All patients undergo an image-guided percutaneous kidney biopsy to obtain epithelial phenotype selective renal cells isolated from the kidney tissue that is then expanded ex vivo over 4-6 weeks, resulting in the REACT biologic product. Patients are randomized 1:1 into the ATG or the DTG. Primary efficacy endpoints for both study groups include eGFR measurements at baseline and at 3-month intervals, through 24 months after the last REACT injection. Safety analyses include biopsy-related complications, REACT injection, and cellular-related adverse events. The study utilizes Good Clinical and Manufacturing Practices and a Data and Safety Monitoring Board. The sample size confers a statistical power of 80% to detect an eGFR change in the ATG compared to the DTG at 24 months with an α = 0.05. LIMITATIONS: Blinding cannot occur due to the intent to treat procedure, biopsy in both groups, and open trial design. CONCLUSION: This multicenter phase II randomized clinical trial is designed to determine the efficacy and safety of REACT in improving or stabilizing renal function among patients with T2DKD stages 3a-4.

Trajectories of the Transition Readiness Assessment Questionnaire Among Youth With Inflammatory Bowel Disease.

OBJECTIVE: The objective of this study was to describe in detail the trends of the Transition Readiness Assessment Questionnaire (TRAQ-20) with respect to patient age and gender among a cohort of 655 youth with inflammatory bowel disease (IBD) to enhance the tool's utility in clinical and research settings. MATERIALS AND METHODS: All participants in the Crohn's and Colitis Foundation's IBD Partners and IBD Partners Kids and Teens Cohorts ages 12 to 21 who completed the TRAQ-20 at least once were included. We computed centile scores for the TRAQ-20 and applied Kernel regression to generate curves. We computed mean scores for each TRAQ-20 domain by age for the overall cohort and stratified by gender. RESULTS: TRAQ-20 scores generally increase with age. Males have a steeper trajectory from ages 17 to 19 compared with females. By age 21, median overall TRAQ-20 scores for women and men were 4.4 and 4.7, respectively. The "Talking with Providers" domain of the TRAQ-20 had high scores throughout the age range of the cohort, while others had lower scores in younger ages and higher scores in older ages. All TRAQ-20 domains had mean scores of 4 or greater (out of a possible 5) among 21-year-olds. CONCLUSIONS: TRAQ-20 scores increase with age. The rate of increase varies by gender. Rates of increase also differ across domains. The use of transition readiness growth curves can help providers and researchers identify patients who are not achieving expected levels of transition readiness and determine the level of transition readiness that a patient much achieve before transfer to adult care.

Histopathological Changes of Long-Term Peritoneal Dialysis Using Physiological Solutions: A Case Report and Review of the Literature.

BACKGROUND: Long-term peritoneal dialysis (PD), especially with nonphysiological solutions, is afflicted with the severe complication of encapsulating peritoneal sclerosis (EPS). Physiologic PD solutions have been introduced to reduce pH trauma. Data on peritoneal biopsies in pediatrics with long-term PD using physiological solutions are scant. CASE REPORT: We report an adolescent who had been on 10-h continuous hourly cycles using mostly 2.27% Physioneal™ for 5 years. There were two episodes of peritonitis in October 2017 (Klebsiella oxytoca) and May 2018 (Klebsiella pneumoniae), which were treated promptly. This adolescent, who lost two kidney transplants from recurrent focal and segmental glomerulosclerosis, underwent a peritoneal membrane biopsy at the time of a third PD catheter placement, 16 months after the second renal transplant. Laparoscopically, the peritoneum appeared grossly normal, but fibrosis and abundant hemosiderin deposition were noted on histology. The thickness of the peritoneum was 200-900 (mean 680) µm; normal for age of 14 years is 297 [IQR 229, 384] µm. The peritoneum biopsy did not show specific EPS findings, as the mesothelial cells were intact, and there was a lack of fibrin exudation, neo-membrane, fibroblast proliferation, infiltration, or calcification. CONCLUSIONS: While the biopsy was reassuring with respect to the absence of EPS, significant histopathological changes suggest that avoiding pH trauma may not ameliorate the effects of glucose exposure in long-term PD.

A.L.L. Y.O.U. N.E.E.D. I.S. L.O.V.E. Manual on health self-management and patient-reported outcomes among low-income young adult Mexicans on chronic dialysis: Feasibility study.

PURPOSE: We evaluated disease knowledge/self-management skills among low-income Mexican young adults maintained on dialysis and to test the effectiveness of the A.L.L. Y.O.U. N.E.E.D. I.S. L.O.V.E (AYNIL) Manual - Spanish Version on patient-reported outcomes. This is a low literacy teaching tool designed with patients and educators' input. DESIGN AND METHODS: A quasi-experimental study was conducted in 17 chronic dialysis patients at Mexico City's Hospital General de México, Dr. Eduardo Liceaga. Ages 18-30-year-old completed disease knowledge/self-management and quality of life measures before the intervention and 6 weeks later. RESULTS: Significant increases were observed on disease knowledge/self-management scores in the STARx questionnaire from 47 (IQ: 40,51) to 50 (IQ: 48,54) p = 0.04. The UNC-TRxANSITION Index increased significantly from 4.8 (IQ: 3.9,5.7) to 7.7 (IQ: 7.5,8.2) p ≤0.001. Significant increases in scores were detected in the "Burden of kidney disease" (p = 0.008), "Effects of kidney disease" " (p = 0.03) and " Dialysis staff encouragement" (p = 0.027) based on the KDQoL survey. CONCLUSIONS: In this vulnerable population, the Spanish version of the A.L.L. Y.O.U. N.E.E.D. I.S. L.O.V.E. - AYNIL Manual improved CKD/ESRD disease knowledge/self-management skills and HRQoL. This study highlighted the need for low-literacy educational tools to improve patient-reported outcomes. PRACTICE IMPLICATIONS: Young adults with CKD/ESRD can benefit from patient-centered educational interventions to enhance their autonomy and the development of self-management behaviors that improve patient-reported outcomes and potential complications of the disease. Special attention is needed in low-income patients with low rates of adherence to treatments and poor self-management skills.

Health-related quality of life in children with chronic kidney disease is affected by the number of medications.

INTRODUCTION: The number of medications could serve as a surrogate for burden of care at home and may affect health-related quality of life (HRQoL) in children with chronic kidney disease (CKD). METHODS: Using baseline data from the Chronic Kidney Disease in Children (CKiD) Study, we modeled HRQoL scores, self-reported by the child (if ≥ 8 years old) and/or caregiver (all children) on unique counts and administrations of CKD- and non-CKD-related medications, using multivariate linear regression. Heterogeneity of associations between HRQoL and medication burden by age group (≥ 8 vs. < 8 years old) were explored. RESULTS: 734 participants median age 11 years, disease duration 8 years, median eGFR 53 mL/min/1.73 m2, 61% male, 22% African-American, 31% glomerular disease were prescribed median 3 unique CKD-related medications. Regarding HRQoL assessment, 201 children were < 8 years old and had only parent-proxy HRQoL score; 533 children ≥ 8 years of age had both child and parent-proxy scores. Overall, parents of children < 8 years old reported higher HRQoL scores than parents of older children: 84 vs. 76. However, in a unified multivariate regression model, HRQoL scores of children < 8 years showed greater decreases as the number of CKD-related medications increased compared to scores for children ≥ 8 years old. CONCLUSION: Average HRQoL scores reported by parents of younger CKD children were higher than those of older CKD children but decreased more with increased CKD medication counts than scores of older children. Considerations of HRQoL may be of particular importance for clinicians and caregivers when managing chronic disease comorbidities in younger children.

Protocol and Baseline Data on Renal Autologous Cell Therapy Injection in Adults with Chronic Kidney Disease Secondary to Congenital Anomalies of the Kidney and Urinary Tract.

BACKGROUND: Advanced cell therapies with autologous, homologous cells show promise to affect reparative and restorative changes in the chronic kidney disease (CKD) nephron. We present our protocol and preliminary analysis of an IRB-approved, phase I single-group, open-label trial that tests the safety and efficacy of Renal Autologous Cell Therapy (REACT; NCT04115345) in adults with congenital anomalies of the kidney and urinary tract (CAKUT). METHODS: Adults with surgically corrected CAKUT and CKD stages 3 and 4 signed an informed consent and served as their "own" baseline control. REACT is an active biological ingredient acquired from a percutaneous tissue acquisition from the patient's kidney cortex. The specimen undergoes a GMP-compliant manufacturing process that harvests the selected renal cells composed of progenitors for renal repair, followed by image-guided locoregional reinjection into the patient's renal cortex. Participants receive 2 doses at 6-month intervals. Primary outcomes are stable renal function and stable/improved quality of life. Additional exploratory endpoints include the impact of REACT on blood pressure, vitamin D levels, hemoglobin, hematocrit and kidney volume by MRI analysis. RESULTS: Four men and 1 woman were enrolled and underwent 5 cell injections. Their characteristics were as follows: mean 52.8 years (SD 17.7 years), 1 Hispanic, 4 non-Hispanic, and 5 white. There were no renal tissue acquisition, cell injection, or cell product-related complications at baseline. CONCLUSION: REACT is demonstrating feasibility and patient safety in preliminary analysis. Autologous cell therapy treatment has the potential to stabilize or improve renal function in CAKUT-associated CKD to delay or avert dialysis. Patient enrollment and follow-up are underway.

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

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

How should we assess renal function in neonates and infants?

AIM: Review of current knowledge on assessing renal function in term and preterm neonates. METHODS: Literature review and analysis of own data. RESULTS: Prematurity, genetic, environmental and maternal factors may alter peak nephron endowment and life-long renal function. Nephrogenesis continues until 34-36 weeks of gestation, but it is altered with premature delivery. Variability of nephron endowment has a substantial impact on the clearance of renally excreted drugs. Postnatally, glomerular function rate (GFR) increases daily, doubles by two weeks, and slowly reaches full maturity at 18 months of age. Ideally, renal function biomarkers should be expressed as age-independent z-scores, and evidence suggests indexing these values to post-conceptual age rather than chronological age. Newborn and maternal serum creatinine correlate tightly for more than 72 hours after delivery, rendering this biomarker unsuitable for the assessment of neonatal renal function. Cystatin C does not cross the placenta and may be the preferred biomarker in the neonate. Here, we provide preliminary data on the natural evolution of the cystatin C eGFR in infancy. CONCLUSION: Cystatin C may be superior for GFR estimation in neonates, but the best approach to drug dosing of renally excreted drugs remains to be established.

Evaluation of the TRxANSITION Index-Parent Version for Assessment of Readiness to Transition to Adult Care Among Youth with Chronic Conditions.

PURPOSE: To develop and evaluate a parent-proxy measure of youth HCT readiness: the TRxANSITION Index-Parent Version. DESIGN AND METHODS: We recruited parents (77% female) and youth (ages 12 to 25) to complete transition readiness measures during outpatient clinic visits. The TRxANSITION Index-Parent Version contains two domains: the Parent Knowledge Domain assessing a parent's knowledge of their youth's illness, and the Parent Proxy Domain, which provides a parental perspective regarding a youth's transition readiness skills. We evaluated the TRxANSITION Index - Parent Version for differences between parent and youth reports of HCT readiness, associations between parent's score and youth's characteristics, and item-category, item-sub-index, and sub-index category correlations. RESULTS: Data from 93 parents-youth dyads were analyzed. Parents scored significantly higher than youth in the Parent Knowledge Domain and similarly in the Parent Proxy Domain. Parents of daughters had significantly higher scores in the Parent Knowledge Domain than parents of sons and reported similar scores to Parents of sons in the Parent Proxy Domain. Only the self-management sub-index significantly correlated with youth's age. The sub-index-domain, item-sub-index, and item-domain correlations assessed were generally large in magnitude (r > 0.5). CONCLUSIONS: The TRxANSITION Index-Parent Version shows promise as a means of assessing parent knowledge of a youth's illness and may provide an accurate proxy assessment of a youth HCT readiness skills. PRACTICE IMPLICATIONS: Obtaining parental perspective on a youth's HCT readiness may provide useful clinical information during the transition process.

School Nurses Practices Promoting Self-Management and Healthcare Transition Skills for Adolescents with Chronic Conditions in Urban Public Schools: A Mixed Methods Study.

Background: Adolescents and young adults (AYA) with chronic conditions should acquire self-management skills as part of their healthcare transition (HCT) from pediatric to adult-focused care. HCT/self-management skills have the potential to help mitigate health disparities among minority AYA with chronic conditions. This study investigated school nurses' practices promoting HCT/self-management skills in urban public schools. Methods: Seventy-nine nurses from three urban school districts in Massachusetts completed a survey of 32 Likert-type questions on HCT/self-management skills, eight demographic questions, and five open-ended practice questions assessing how often they have asked students with chronic conditions about HCT/self-management skills, based on the UNC TRxANSITION IndexTM. Results: Among the 79 school nurses who participated (response rate 76%), 67% never or rarely assessed students' knowledge of HCT/self-management, and 90% would use a tool that promotes/measures HCT/self-management skills. Conclusion: In our study sample, most school nurses acknowledged the importance of assessing HCT/self-management skills. The majority favored using a tool to promote these skills.

A Cross-Sectional Study of Growth and Metabolic Bone Disease in a Pediatric Global Cohort Undergoing Chronic Hemodialysis.

OBJECTIVE: We sought to assess worldwide differences among pediatric patients undergoing hemodialysis. Because practices differ widely regarding nutritional resources, treatment practice, and access to renal replacement therapy, investigators from the Pediatric Investigation and Close Collaboration to examine Ongoing Life Outcomes, the pediatric subset of the MONitoring Dialysis Outcomes Cohort (PICCOLO MONDO) performed this cross-sectional study. We hypothesized that growth would be better in developed countries, possibly at the expense of bone mineral disease. STUDY DESIGN: In this cross-sectional study, we analyzed growth by height z score and recommended age-specific bone mineral metabolism markers from 225 patients <18 years of age maintained on hemodialysis, between the years of 2000 to 2012 from 21 countries in different regions. RESULTS: The patients' median age was 16 (IQR 14-17) years, and 45% were females. A height z score less than the third percentile was noted in 34% of the cohort, whereas >66% of patients reported normal heights, with patients from North America having the greatest proportion (>80%). More than 70% of the entire cohort had greater than the age-recommended levels of phosphorus, particularly in the Asia-Pacific and North America, where we also observed the greatest body mass index z score (0.99 ± 1.6) and parathyroid hormone levels (557.1 [268.4-740.5]). Below-recommended parathyroid hormone levels were noted in 26% and elevated levels in 61% of the entire sample, particularly in the Asia Pacific region. Lower-than-recommended calcium levels were noted in 36% of the entire cohort, particularly in Latin America. CONCLUSIONS: We found regional differences in growth- and age-adjusted bone mineral metabolism markers. Children from North America had the best growth, received the most dialysis, but also had the worst phosphate control and body mass index z scores.