Changes in the cardiovascular risk profile in children approaching kidney replacement therapy.

Background: Despite significant cardiovascular (CV) morbidity in children on dialysis and after kidney transplantation, data on the evolution of CV damage in children with chronic kidney disease (CKD) approaching kidney replacement therapy (KRT) is unknown. Methods: The burden, progression, and predictors of CV damage before KRT onset were explored in two prospective multicenter cohorts from Europe and Canada: Cardiovascular Comorbidity in Children with CKD (4C) and Haemodiafiltration, Heart and Height (3H) studies, conducted from 2009-19 and 2013-16, respectively. CV damage and risk factors were evaluated (i) cross sectionally at KRT-start (n = 248), and (ii) longitudinally over the 2-years preceding KRT start (n = 157; 331 patient-visits). Longitudinal analyses with mixed-effects models estimated associations of modifiable CV risk factors with change in carotid intima-media thickness (cIMT) standard deviation score (SDS), pulse wave velocity (PWV-SDS), left ventricular (LV) mass and systolic dysfunction. Findings: 248 patients, age 14.3 (12.2, 16.2) years were evaluated at median 35 (28-114) days before KRT start. Elevated cIMT-SDS and PWV-SDS were present in 43% and 25%, and LV hypertrophy and systolic dysfunction in 49% and 33%. Aortic stiffness and LV hypertrophy significantly increased, especially in the year before KRT start (adjusted odds ratio, OR 0.33, P = 0.002 and OR 0.54, P = 0.01, respectively). 79% of children had >3 modifiable CV risk factors at KRT onset. Diastolic BP and BMI were strongly associated with a linear increase in all CV measures. After controlling for CV risk factors, the time to KRT onset no longer predicted the burden of CV damage. Interpretation: This comprehensive CV evaluation shows the progressive accrual of modifiable risk factors and a high burden of CV damage in the years preceding KRT onset. CV damage in the pre-KRT period is preventable. Funding: Supported by EU4Health Programme (101085068) and Kidney Research UK (RP39/2013).

Factors influencing circuit lifetime in paediatric continuous kidney replacement therapies - results from the EurAKId registry.

BACKGROUND: Continuous kidney replacement therapy (CKRT) has recently become the preferred kidney replacement modality for children with acute kidney injury (AKI). We hypothesise that CKRT technical parameters and treatment settings in addition to the clinical characteristics of patients may influence the circuit lifetime in children. METHODS: The study involved children included in the EurAKId registry (NCT02960867), who underwent CKRT treatment. We analysed patient characteristics and CKRT parameters. The primary end point was mean circuit lifetime (MCL). Secondary end points were number of elective circuit changes and occurrence of dialysis-related complications. RESULTS: The analysis was composed of 247 children who underwent 37,562 h of CKRT (median 78, IQR 37-165 h per patient). A total of 1357 circuits were utilised (3, IQR 2-6 per patient). MCL was longer in regional citrate anticoagulation (RCA), compared to heparin (HA) and no anticoagulation (NA) (42, IQR 32-58 h; 24, IQR 14-34 h; 18, IQR 12-24 h, respectively, p < 0.001). RCA was associated with longer MCL regardless of the patient's age or dialyser surface. In multivariate analysis, MCL correlated with dialyser surface area (beta = 0.14, p = 0.016), left internal jugular vein vascular access site (beta = -0.37, p = 0.027), and the use of HA (beta = -0.14, p = 0.038) or NA (beta = -0.37, p < 0.001) vs. RCA. RCA was associated with the highest ratio of elective circuit changes and the lowest incidence of complications. CONCLUSION: Anticoagulation modality, dialyser surface, and vascular access site influence MCL. RCA should be considered when choosing first-line anticoagulation for CKRT in children. Further efforts should focus on developing guidelines and clinical practice recommendations for paediatric CKRT.

Prospective Study of Modifiable Risk Factors of Arterial Hypertension and Left Ventricular Hypertrophy in Pediatric Patients on Hemodialysis.

Introduction: Fluid and salt overload in patients on dialysis result in high blood pressure (BP), left ventricular hypertrophy (LVH) and hemodynamic instability, resulting in cardiovascular morbidity. Methods: Analysis of 910 pediatric patients on maintenance hemodialysis/hemodiafiltration (HD/HDF), prospectively followed-up with 2758 observations recorded every 6-months in the International Pediatric Hemodialysis Network (IPHN). Results: Uncontrolled hypertension was present in 55% of observations, with 27% of patients exhibiting persistently elevated predialysis BP. Systolic and diastolic age- and height-standardized BP (BP-SDS) were independently associated with the number of antihypertensive medications (odds ratio [OR] = 1.47, 95% confidence interval 1.39-1.56, 1.36 [1.23-1.36]) and interdialytic weight gain (IDWG; 1.19 [1.14-1.22], 1.09 [1.06-1.11]; all P < 0.0001). IDWG was related to urine output (OR = 0.27 [0.23-0.32]) and dialysate sodium (dNa; 1.06 [1.01-1.10]; all P < 0.0001). The prevalence of masked hypertension was 24%, and HD versus HDF use was an independent risk factor of elevated age- and height-standardized mean arterial pressure (MAP-SDS) (OR = 2.28 [1.18-4.41], P = 0.01). Of the 1135 echocardiograms, 51% demonstrated LVH. Modifiable risk factors included predialysis systolic BP-SDS (OR = 1.06 [1.04-1.09], P < 0.0001), blood hemoglobin (0.97 [0.95-0.99], P = 0.004), HD versus HDF modality (1.09 [1.02-1.18], P = 0.01), and IDWG (1.02 [1.02-1.03], P = 0.04). In addition, HD modality increased the risk of LVH progression (OR = 1.23 [1.03-1.48], P = 0.02). Intradialytic hypotension (IDH) was prevalent in patients progressing to LVH and independently associated with predialysis BP-SDS below 25th percentile, lower number of antihypertensives, HD versus HDF modality, ultrafiltration (UF) rate, and urine output, but not with dNa. Conclusion: Uncontrolled hypertension and LVH are common in pediatric HD, despite intense pharmacologic therapy. The outcome may improve with use of HDF, and superior anemia and IDWG control; the latter via lowering dNa, without increasing the risk of IDH.

Best Practice of Peritoneal Dialysis-Associated Gram-Negative Peritonitis in Children: Insights From the International Pediatric Peritoneal Dialysis Network Registry.

Introduction: Gram-negative peritonitis (GNP) is associated with significant morbidity in children receiving long-term peritoneal dialysis (PD) and current treatment recommendations are based on limited data. Methods: Analysis of 379 GNP episodes in 308 children (median age 6.9 years, interquartile range [IQR]: 3.0-13.6) from 45 centers in 28 countries reported to the International Pediatric Peritoneal Dialysis Network registry between 2011 and 2023. Results: Overall, 74% of episodes responded well to empiric therapy and full functional recovery (FFR) was achieved in 82% of cases. In vitro bacterial susceptibility to empiric antibiotics and lack of severe abdominal pain at onset were associated with a good initial response. Risk factors for failure to achieve FFR included severe abdominal pain at onset and at 60 to 72 hours from treatment initiation (odds ratio [OR]: 3.81, 95% confidence interval [CI]: 2.01-7.2 and OR: 3.94, 95% CI: 1.06-14.67, respectively), Pseudomonas spp. etiology (OR: 1.73, 95% CI: 1.71-4.21]) and in vitro bacterial resistance to empiric antibiotics (OR: 2.40, 95% CI: 1.21-4.79); the risk was lower with the use of monotherapy as definitive treatment (OR: 0.40, 95% CI: 0.21-0.77). Multivariate analysis showed no benefit of dual antibiotic therapy for treatment of Pseudomonas peritonitis after adjustment for age, presenting symptomatology, 60 to 72-hour treatment response, and treatment duration. Monotherapy with cefazolin in susceptible Enterobacterales peritonitis resulted in a similar FFR rate (91% vs. 93%) as treatment with ceftazidime or cefepime monotherapy. Conclusion: Detailed microbiological assessment, consisting of patient-specific and center-specific antimicrobial susceptibility data, should guide empiric treatment. Treatment "deescalation" with the use of monotherapy and narrow spectrum antibiotics according to susceptibility data is not associated with inferior outcomes and should be advocated in the context of emerging bacterial resistance.

Dyslipidemia in children with chronic kidney disease-findings from the Cardiovascular Comorbidity in Children with Chronic Kidney Disease (4C) study.

BACKGROUND: Dyslipidemia is an important and modifiable risk factor for CVD in children with CKD. METHODS: In a cross-sectional study of baseline serum lipid levels in a large prospective cohort study of children with stage 3-5 (predialysis) CKD, frequencies of abnormal lipid levels and types of dyslipidemia were analyzed in the entire cohort and in subpopulations defined by fasting status or by the presence of nephrotic range proteinuria. Associated clinical and laboratory characteristics were determined by multivariable linear regression analysis. RESULTS: A total of 681 patients aged 12.2 ± 3.3 years with a mean eGFR of 26.9 ± 11.6 ml/min/1.73 m2 were included. Kidney diagnosis was classified as CAKUT in 69%, glomerulopathy in 8.4%, and other disorders in 22.6% of patients. Nephrotic range proteinuria (defined by a urinary albumin/creatinine ratio > 1.1 g/g) was present in 26.9%. Dyslipidemia was found in 71.8%, and high triglyceride (TG) levels were the most common abnormality (54.7%). Fasting status (38.9%) had no effect on dyslipidemia status. Except for a significant increase in TG in more advanced CKD, lipid levels and frequencies of dyslipidemia were not significantly different between CKD stages. Hypertriglyceridemia was associated with younger age, lower eGFR, shorter duration of CKD, higher body mass index (BMI-SDS), lower serum albumin, and higher diastolic blood pressure. CONCLUSIONS: Dyslipidemia involving all lipid fractions, but mainly TG, is present in the majority of patients with CKD irrespective of CKD stage or fasting status and is significantly associated with other cardiovascular risk factors.

Steroid-Resistant Nephrotic Syndrome due to NPHS2 Variants Is Not Associated With Posttransplant Recurrence.

Introduction: Unlike idiopathic nephrotic syndrome (NS), hereditary podocytopathies are not expected to recur after kidney transplantation. However, some reports of posttransplant recurrence of NS in patients carrying variants in the NPHS2 gene have been described, notably with the p.Arg138Gln variant, which is more prevalent in Europe. The objective of this study was to assess the risk of recurrence after kidney transplantation in a large cohort of patients with biallelic NPHS2 pathogenic variants. Methods: Since January 2010, 61 patients identified at Necker-Enfants Malades Hospital and 56 enrolled in the PodoNet Registry with biallelic variants in the NPHS2 gene were transplanted and were compared with 44 transplanted children with steroid-resistant NS (SRNS) without any identified pathogenic variant. Results: Of the 117 patients, 23 carried the p.Arg138Gln variant in the homozygous state and 16 in the compound heterozygous state. The other 78 patients carried different variants in the homozygous (n = 44) or compound heterozygous state. Only 1 patient with NPHS2-related SRNS experienced posttransplant recurrence (median follow-up of cohort 8.5 years [2.5-15]). Conversely, 7 of 44 patients (16%) without any identified pathogenic variant recurred within a maximum of 7 days after transplantation (median follow-up 8.9 years [0.6-13.9]). Conclusion: In this large cohort, the risk of patients with causative variants in the NPHS2 gene to develop NS recurrence after kidney transplantation was extremely low. This is coherent with the pathophysiology of intrinsic slit-diaphragm disease. These data are reassuring and should be considered when counselling patients, making living kidney donation, whether related or not, a safe choice.

The creation of an adaptable informed consent form for research purposes to overcome national and institutional bottlenecks in ethics review: experience from rare disease registries.

Background: The lack of harmonization of evaluation criteria by Ethics Committees in the European Union (EU) has led to inconsistent ethics reviews received by research sites participating in multicenter non-interventional studies. The European General Data Protection Regulation (GDPR) appears to be implemented at national level with a substantial degree of variance in interpretation. The European Reference Networks (ERNs) were struggling in setting an Informed Consent Form (ICF) for registries, allowing reuse of data for research purposes. The aim of this work is to develop an adaptable ICF for research purposes to be used in ERN registries. Methods: To work on this challenge, a team was established within the European Joint Programme on Rare Diseases (EJP RD) to develop a patients' registry ICF template allowing easy adaptation to ERNs, country, and site-level specificities. ERN and patients' representatives validated the choice of developing a GDPR-compliant template for research purposes. The feedback received from 34 Ethics Committees on the Clinical Patient Management System ICF, including the submission of patients' data to the ERN registries and the EU consent regulatory framework were analyzed along with existing ontologies for data access and reuse. An adaptable ICF was developed following iterative cycles of consultation and review by clinicians, research experts, ethics and regulatory advisors, and patients' representatives. The development of pediatric material for minor participants was also undertaken. Results and Conclusion: Research oriented ICF templates for adults and for parents/legal representatives of patients were released in 26 national languages. This adaptable ICF aims to foster, according to patients' preferences, the reuse of registries data for research purposes in compliance with the applicable laws and standards. Pediatric material is being finalized to collect minors' assent. ICF machine-readability is also progressing to enhance data discovery and facilitate its access and reuse conditions.

Trends and socioeconomic inequality of the burden of congenital abnormalities of the kidney and urinary tract among children and adolescents.

BACKGROUND: Although congenital abnormalities of the kidney and urinary tract (CAKUT) is the leading cause of childhood onset chronic kidney disease (CKD) and kidney failure, comprehensive information on the disease burden among children and adolescents globally is lacking. We aim to report the trends and socioeconomic inequality of CAKUT burden for people aged 0-24 years from 1990 to 2019·. METHODS: We reported the prevalence, mortality and disability-adjusted life-years (DALYs) for CAKUT based on the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, quantified the association of disease burden and socio-demographic index (SDI), calculated the slope index of inequality (SII) the relative index of inequality (RII) and concentration index. RESULTS: In 2019, the global prevalence, mortality, and DALYs of CAKUT among individuals aged 0-24 years were 167.11 (95%Confident Interval 166.97, 167.25), 0.30 (0.29, 0.30), and 32.22 (32.16, 32.29) per 100 000 population. The greatest prevalence, mortality and DALYs were recorded in the 0-4 year age group. The greatest mortality and DALYs were recorded in low SDI countries and territories. During 1990 to 2019, the prevalence, mortality and DALYs decreased globally, while in low and low-middle countries and territories the reduction was much less slower. India, Nigeria and Pakistan had the highest DALYs. Saudi Arabia and China exhibited a markedly decrease of CAKUT burden. Globally for every 0.1 increase in SDI, there was a 20.53% reduction in mortality, a 16.31% decrease in DALYs, but a 0.38% rise in prevalence. CONCLUSIONS: Inequality for disease burden of varying SDI was increasing globally. Thus, specific preventive and health service measures are needed to reduce the global burden from CAKUT.

Autoantibodies Targeting Nephrin in Podocytopathies.

BACKGROUND: Minimal change disease and primary focal segmental glomerulosclerosis in adults, along with idiopathic nephrotic syndrome in children, are immune-mediated podocytopathies that lead to nephrotic syndrome. Autoantibodies targeting nephrin have been found in patients with minimal change disease, but their clinical and pathophysiological roles are unclear. METHODS: We conducted a multicenter study to analyze antinephrin autoantibodies in adults with glomerular diseases, including minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, IgA nephropathy, antineutrophil cytoplasmic antibody-associated glomerulonephritis, and lupus nephritis, as well as in children with idiopathic nephrotic syndrome and in controls. We also created an experimental mouse model through active immunization with recombinant murine nephrin. RESULTS: The study included 539 patients (357 adults and 182 children) and 117 controls. Among the adults, antinephrin autoantibodies were found in 46 of the 105 patients (44%) with minimal change disease, 7 of 74 (9%) with primary focal segmental glomerulosclerosis, and only in rare cases among the patients with other conditions. Of the 182 children with idiopathic nephrotic syndrome, 94 (52%) had detectable antinephrin autoantibodies. In the subgroup of patients with active minimal change disease or idiopathic nephrotic syndrome who were not receiving immunosuppressive treatment, the prevalence of antinephrin autoantibodies was as high as 69% and 90%, respectively. At study inclusion and during follow-up, antinephrin autoantibody levels were correlated with disease activity. Experimental immunization induced a nephrotic syndrome, a minimal change disease-like phenotype, IgG localization to the podocyte slit diaphragm, nephrin phosphorylation, and severe cytoskeletal changes in mice. CONCLUSIONS: In this study, circulating antinephrin autoantibodies were common in patients with minimal change disease or idiopathic nephrotic syndrome and appeared to be markers of disease activity. Their binding at the slit diaphragm induced podocyte dysfunction and nephrotic syndrome, which highlights their pathophysiological significance. (Funded by Deutsche Forschungsgemeinschaft and others.).

Characterization of patients with aHUS and associated triggers or clinical conditions: A Global aHUS Registry analysis.

INTRODUCTION: Atypical haemolytic uremic syndrome (aHUS) is a rare form of thrombotic microangiopathy (TMA) associated with complement dysregulation; aHUS may be associated with other 'triggers' or 'clinical conditions'. This study aimed to characterize this patient population using data from the Global aHUS Registry, the largest collection of real-world data on patients with aHUS. METHODS: Patients enrolled in the Global aHUS Registry between April 2012 and June 2021 and with recorded aHUS-associated triggers or clinical conditions prior/up to aHUS onset were analysed. aHUS was diagnosed by the treating physician. Data were classified by age at onset of aHUS (< or ≥18 years) and additionally by the presence/absence of identified pathogenic complement genetic variant(s) and/or anti-complement factor H (CFH) antibodies. Genetically/immunologically untested patients were excluded. RESULTS: 1947 patients were enrolled in the Global aHUS Registry by June 2021, and 349 (17.9%) met inclusion criteria. 307/349 patients (88.0%) had a single associated trigger or clinical condition and were included in the primary analysis. Malignancy was most common (58/307, 18.9%), followed by pregnancy and acute infections (both 53/307, 17.3%). Patients with an associated trigger or clinical condition were generally more likely to be adults at aHUS onset. CONCLUSION: Our analysis suggests that aHUS-associated triggers or clinical conditions may be organized into clinically relevant categories, and their presence does not exclude the concurrent presence of pathogenic complement genetic variants and/or anti-CFH antibodies. Considering a diagnosis of aHUS with associated triggers or clinical conditions in patients presenting with TMA may allow faster and more appropriate treatment.

Clinical practice recommendations for kidney involvement in tuberous sclerosis complex: a consensus statement by the ERKNet Working Group for Autosomal Dominant Structural Kidney Disorders and the ERA Genes & Kidney Working Group.

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by the presence of proliferative lesions throughout the body. Management of TSC is challenging because patients have a multifaceted systemic illness with prominent neurological and developmental impact as well as potentially severe kidney, heart and lung phenotypes; however, every organ system can be involved. Adequate care for patients with TSC requires a coordinated effort involving a multidisciplinary team of clinicians and support staff. This clinical practice recommendation was developed by nephrologists, urologists, paediatric radiologists, interventional radiologists, geneticists, pathologists, and patient and family group representatives, with a focus on TSC-associated kidney manifestations. Careful monitoring of kidney function and assessment of kidney structural lesions by imaging enable early interventions that can preserve kidney function through targeted approaches. Here, we summarize the current evidence and present recommendations for the multidisciplinary management of kidney involvement in TSC.

Investigating the use of finerenone in children with chronic kidney disease and proteinuria: design of the FIONA and open-label extension studies.

INTRODUCTION: Proteinuria is a modifiable risk factor for chronic kidney disease (CKD) progression in children. Finerenone, a selective, non-steroidal, mineralocorticoid receptor antagonist (MRA) has been approved to treat adults with CKD associated with type 2 diabetes mellitus (T2DM) following results from the phase III clinical trials FIDELIO-DKD (NCT02540993) and FIGARO-DKD (NCT02545049). In a pre-specified pooled analysis of both studies (N = 13,026), finerenone was shown to have an acceptable safety profile and was efficacious in decreasing the risk of adverse kidney and cardiovascular outcomes and of proteinuria. OBJECTIVE: FIONA and the associated open-label extension (OLE) study aim to demonstrate that combining finerenone with an angiotensin-converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) is safe, well-tolerated, and effective in sustainably reducing urinary protein excretion in children with CKD and proteinuria. DESIGN: FIONA (NCT05196035; Eudra-CT: 2021-002071-19) is a randomized (2:1), double-blind, placebo-controlled, multicenter, phase III study of 6 months' duration in approximately 219 pediatric patients. Patients must have a clinical diagnosis of CKD (an eGFR ≥ 30 mL/min/1.73 m2 if ≥ 1 to < 18 years or a serum creatinine level ≤ 0.40 mg/dL for infants 6 months to < 1 year) with significant proteinuria despite ACEi or ARB usage. The primary objective is to demonstrate that finerenone, added to an ACEi or ARB, is superior to placebo in reducing urinary protein excretion. FIONA OLE (NCT05457283; Eudra-CT: 2021-002905-89) is a single-arm, open-label study, enrolling participants who have completed FIONA. The primary objective of FIONA OLE is to provide long-term safety data. FIONA has two primary endpoints: urinary protein-to-creatinine ratio (UPCR) reduction of ≥ 30% from baseline to day 180 and percent change in UPCR from baseline to day 180. A sample size of 198 participants (aged 2 to < 18 years) in FIONA will provide at least 80% power to reject the null hypothesis of either of the two primary endpoints. CONCLUSION: FIONA is evaluating the use of finerenone in children with CKD and proteinuria. Should safety, tolerability, and efficacy be demonstrated, finerenone could become a useful additional therapeutic agent in managing proteinuria and improving kidney outcomes in children with CKD. TRIAL REGISTRATION: ClinicalTrials.gov NCT05196035. Registered on 19 January 2022.

Long-term Effects of Kidney Transplantation Compared With Dialysis on Intima-media Thickness in Children-Results From the 4C-T Study.

BACKGROUND: Children requiring kidney replacement therapy experience high burden of cardiovascular (CV) disease leading to increased mortality. Intima-media thickness (IMT) indicating atherosclerosis is a validated surrogate marker for future CV events. METHODS: We investigated the effect of different treatment modalities (dialysis, preemptive kidney transplantation (KTx), late KTx after dialysis) on IMT by multivariable linear mixed-effect modeling. Patients were enrolled in a prospective cohort study. RESULTS: A total of 261 analyzed children had a mean follow-up of 3 y. Children after preemptive and late KTx had lower levels of IMT when compared with dialysis. Using an interaction term, a significant progression of IMT over time was seen during dialysis (ß = 0.0053 mm/y, P   =  0.004). IMT before the start of therapy was the most influential determinant in all models. Low IMT was associated with maintenance steroid treatment after preemptive KTx. High IMT on dialysis was associated with higher systolic blood pressure, lower body mass index, lower serum albumin, and lower bicarbonate. CONCLUSIONS: IMT remained rather stable in children several years after KTx. In contrast, children on dialysis had higher IMT values, which increased over time. In these children, blood pressure control, calorie and protein intake, and acid-base homeostasis seem important. Taken together, children might profit from early transplantation to limit accumulation of CV risk.

Urine soluble TLR4 levels may contribute to predict urinary tract infection in children: the UTILISE Study.

BACKGROUND: One of the most common bacterial infections in childhood is urinary tract infection (UTI). Toll-like receptors (TLRs) contribute to immune response against UTI recognizing specific pathogenic agents. Our aim was to determine whether soluble TLR4 (sTLR4), soluble TLR5 (sTLR5) and interleukin 8 (IL-8) can be used as biomarkers to diagnose UTI. We also aimed to reveal the relationship between urine Heat Shock Protein 70 (uHSP70) and those biomarkers investigated in this study. METHODS: A total of 802 children from 37 centers participated in the study. The participants (n = 282) who did not meet the inclusion criteria were excluded from the study. The remaining 520 children, including 191 patients with UTI, 178 patients with non-UTI infections, 50 children with contaminated urine samples, 26 participants with asymptomatic bacteriuria and 75 healthy controls were included in the study. Urine and serum levels of sTLR4, sTLR5 and IL-8 were measured at presentation in all patients and after antibiotic treatment in patients with UTI. RESULTS: Urine sTLR4 was higher in the UTI group than in the other groups. UTI may be predicted using 1.28 ng/mL as cut-off for urine sTLR4 with 68% sensitivity and 65% specificity (AUC = 0.682). In the UTI group, urine sTLR4 levels were significantly higher in pyelonephritis than in cystitis (p < 0.0001). Post-treatment urine sTLR4 levels in the UTI group were significantly lower than pre-treatment values (p < 0.0001). CONCLUSIONS: Urine sTLR4 may be used as a useful biomarker in predicting UTI and subsequent pyelonephritis in children with UTI. A higher resolution version of the Graphical abstract is available as Supplementary information.

Decline in Left Ventricular Early Systolic Function with Worsening Kidney Function in Children with Chronic Kidney Disease: Insights from the 4C and HOT-KID Studies.

INTRODUCTION: Adults with childhood-onset chronic kidney disease (CKD) have an increased risk of cardiovascular disease. First-phase ejection fraction (EF1), a novel measure of early systolic function, may be a more sensitive marker of left ventricular dysfunction than other markers in children with CKD. OBJECTIVE: To examine whether EF1 is reduced in children with CKD. METHODS: Children from the 4C and HOT-KID studies were stratified according to estimated glomerular filtration rate (eGFR). The EF1 was calculated from the fraction of left ventricular (LV) volume ejected up to the time of peak aortic flow velocity. RESULTS: The EF1 was measured in children ages 10.9 ± 3.7 (mean ± SD) years, 312 with CKD and 63 healthy controls. The EF1 was lower, while overall ejection fraction was similar, in those with CKD compared with controls and decreased across stages of CKD (29.3% ± 3.7%, 23.5% ± 4.5%, 19.8% ± 4.0%, 18.5% ± 5.1%, and 16.7% ± 6.6% in controls, CKD 1, 2, 3, and ≥ 4, respectively, P < .001). The relationship of EF1 to eGFR persisted after adjustment for relevant confounders (P < .001). The effect size for association of measures of LV structure or function with eGFR (SD change per unit change in eGFR) was greater for EF1 (ß = 0.365, P < .001) than for other measures: LV mass index (ß = -0.311), relative wall thickness (ß = -0.223), E/e' (ß = -0.147), and e' (ß = 0.141) after adjustment for confounders in children with CKD. CONCLUSIONS: Children with CKD exhibit a marked and progressive decline in EF1 with falling eGFR. This suggests that EF1 is a more sensitive marker of LV dysfunction when compared to other structural or functional measures and that early LV systolic function is a key feature in the pathophysiology of cardiac dysfunction in CKD.

Worldwide disparities in access to treatment and investigations for nephropathic cystinosis: a 2023 perspective.

BACKGROUND: Nephropathic cystinosis (NC) is a rare lysosomal disease, leading to early kidney failure and extra-renal comorbidities. Its prognosis strongly relies on early diagnosis and treatment by cysteamine. Developing economies (DEing) face many challenges when treating patients for rare and chronic diseases. The aim here is to evaluate the access to investigations and treatment in DEing, and to assess for potential inequalities with Developed Economies (DEed). METHODS: In this international cross-sectional study, a questionnaire on access, price and reimbursement of genetic, biological analyses, and treatment was sent to nephrology centers worldwide during 2022. RESULTS: A total of 109 centers responded, coming from 49 countries and managing 741 patients: 43 centers from 30 DEing and Economies in transition (TrE), and 66 from 19 DEed. In 2022, genetics availability was 63% in DEing and 100% in DEed, whereas intra leukocytes cystine levels (IL-CL) were available for 30% of DEing patients, and 94% of DEed patients, both increasing over the last decade, as has access to immediate release cysteamine and to cysteamine eye drops in DEing. However, delayed released cysteamine can be delivered to only 7% vs. 74% of patients from DEing and DEed, respectively, and is still poorly reimbursed in DEing. CONCLUSIONS: Over the last decade, access to investigations (namely genetics and IL-CL) and to cysteamine have improved in DEing and TrE. However, discrepancies remain with DEed: access to delayed released cysteamine is limited, and reimbursement is still profoundly insufficient, therefore limiting their current use.

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.

Post-transplant recurrence of focal segmental glomerular sclerosis: consensus statements.

Focal segmental glomerular sclerosis (FSGS) is 1 of the primary causes of nephrotic syndrome in both pediatric and adult patients, which can lead to end-stage kidney disease. Recurrence of FSGS after kidney transplantation significantly increases allograft loss, leading to morbidity and mortality. Currently, there are no consensus guidelines for identifying those patients who are at risk for recurrence or for the management of recurrent FSGS. Our work group performed a literature search on PubMed/Medline, Embase, and Cochrane, and recommendations were proposed and graded for strength of evidence. Of the 614 initially identified studies, 221 were found suitable to formulate consensus guidelines for recurrent FSGS. These guidelines focus on the definition, epidemiology, risk factors, pathogenesis, and management of recurrent FSGS. We conclude that additional studies are required to strengthen the recommendations proposed in this review.