The Hyponatremic Hypertensive Syndrome in a Preterm Infant: A Case of Severe Hyponatremia with Neurological Sequels

Objective. To report the irreversible severe neurological symptoms following the hyponatremic hypertensive syndrome (HHS) in an infant after umbilical arterial catheterization. Design. Case report with review of the literature. Setting. Neonatal intensive care unit at a tertiary care children's hospital. Patient. A three-week-old preterm infant. Conclusions. In evaluating a neonate with hyponatremia and hypertension, HHS should be considered, especially in case of umbilical arterial catheterization. In case of diagnostic delay, there is a risk of severe irreversible neurological damage

Clinical and Molecular Characteristics and Outcome of Cystic Partially Differentiated Nephroblastoma and Cystic Nephroma: A Narrative Review of the Literature

In children presenting with a predominantly cystic renal tumor, the most likely diagnoses include cystic partially differentiated nephroblastoma (CPDN) and cystic nephroma (CN). Both entities are rare and limited information on the clinical and molecular characteristics, treatment, and outcome is available since large cohort studies are lacking. We performed an extensive literature review, in which we identified 113 CPDN and 167 CN. The median age at presentation for CPDN and CN was 12 months (range: 3 weeks–4 years) and 16 months (prenatal diagnosis–16 years), respectively. No patients presented with metastatic disease. Bilateral disease occurred in both entities. Surgery was the main treatment for both. Two/113 CPDN patients and 26/167 CN patients had previous, concomitant, or subsequent other tumors. Unlike CPDN, CN was strongly associated with somatic (n = 27/29) and germline (n = 12/12) DICER1-mutations. Four CPDN patients and one CN patient relapsed. Death was reported in six/103 patients with CPDN and six/118 CN patients, none directly due to disease. In conclusion, children with CPDN and CN are young, do not present with metastases, and have an excellent outcome. Awareness of concomitant or subsequent tumors and genetic testing is important. International registration of cystic renal tumor cohorts is required to enable a better understanding of clinical and genetic characteristics

Epidemiology and Outcome of Critically Ill Pediatric Cancer and Hematopoietic Stem Cell Transplant Patients Requiring Continuous Renal Replacement Therapy:A Retrospective Nationwide Cohort Study

OBJECTIVE: Acute kidney injury requiring continuous renal replacement therapy is a serious treatment-related complication in pediatric cancer and hematopoietic stem cell transplant patients. The purpose of this study was to assess epidemiology and outcome of these patients requiring continuous renal replacement therapy in the PICU. DESIGN: A nationwide, multicenter, retrospective, observational study. SETTING: Eight PICUs of a tertiary care hospitals in the Netherlands. PATIENTS: Pediatric cancer and hematopoietic stem cell transplant patients (cancer and noncancer) who received continuous renal replacement therapy from January 2006 to July 2017 in the Netherlands.None. MEASUREMENT AND MAIN RESULTS: Of 1,927 PICU admissions of pediatric cancer and hematopoietic stem cell transplant patients, 68 of 70 evaluable patients who received continuous renal replacement therapy were included. Raw PICU mortality was 11.2% (216/1,972 admissions). PICU mortality of patients requiring continuous renal replacement therapy was 54.4% (37/68 patients). Fluid overload (odds ratio, 1.08; 95% CI, 1.01-1.17) and need for inotropic support (odds ratio, 6.53; 95% CI, 1.86-23.08) at the start of continuous renal replacement therapy were associated with PICU mortality. Serum creatinine levels increased above 150% of baseline 3 days before the start of continuous renal replacement therapy. Urine production did not reach the critical limit of oliguria. In contrast, body weight (fluid overload) increased already 5 days prior to continuous renal replacement therapy initiation. CONCLUSIONS: PICU mortality of pediatric cancer and hematopoietic stem cell transplant patients requiring continuous renal replacement therapy is sadly high. Fluid overload at the initiation of continuous renal replacement therapy is the most important and earliest predictor of PICU mortality. Our results suggest that the most commonly used criteria of acute kidney injury, that is, serum creatinine and urine production, are not useful as a trigger to initiate continuous renal replacement therapy. This highlights the urgent need for prospective studies to generate recommendations for effective therapeutic interventions at an early phase in this specific patient population

Screen-based identification and validation of four new ion channels as regulators of renal ciliogenesis

©2015. To investigate the contribution of ion channels to ciliogenesis, we carried out a small interfering RNA (siRNA)-based reverse genetics screen of all ion channels in the mouse genome in murine inner medullary collecting duct kidney cells. This screen revealed four candidate ion channel genes: Kcnq1, Kcnj10, Kcnf1 and Clcn4. We show that these four ion channels localize to renal tubules, specifically to the base of primary cilia. We report that human KCNQ1 Long QT syndrome disease alleles regulate renal ciliogenesis; KCNQ1-p. R518X, -p.A178T and -p.K362R could not rescue ciliogenesis after Kcnq1-siRNA-mediated depletion in contrast to wild-type KCNQ1 and benign KCNQ1-p.R518Q, suggesting that the ion channel function of KCNQ1 regulates ciliogenesis. In contrast, we demonstrate that the ion channel function ofKCNJ10 is independent of its effect on ciliogenesis. Our data suggest that these four ion channels regulate renal ciliogenesis through the periciliary diffusion barrier or the ciliary pocket, with potential implication as genetic contributors to ciliopathy pathophysiology. The new functional roles of a subset of ion channels provide new insights into the disease pathogenesis of channelopathies, which might suggest future therapeutic approaches

GeNepher data- and biobank for patients with (suspected) genetic kidney disease: Rationale, design and status update

Background Clinical research on monogenic kidney disease (MKD) is thriving and the need for large cohorts, prospective data collection and biobanking is increasing. We aim to create a sustainable large MKD biobank with a vast amount of uniformly collected high-quality data that is readily available for future research, with an infrastructure that allows for recontacting participants. Methods The GeNepher data- and biobank is an ongoing data- and sample collection that includes patients and family members with known and/or suspected MKD. With a tiered approach participants can give broad consent for including their 1) available medical data (including genetic testing results), 2) inclusion of massively parallel sequencing data for add-on analysis, and 3) additional biobank sampling (e.g. urine for tubuloids, skin biopsy for fibroblasts). Recontacting is possible for additional data collection, novel research opportunities and return of relevant findings. Discussion The GeNepher data- and biobank collects prospective and retrospective data from kidney disease patients and their relatives. The broad consent allows for research that extends beyond one specific research question. Herewith, this biobank aims to 1) increase the scientific knowledge based on disease mechanisms including (novel) monogenic causes, 2) study modifiers, 3) improve care, including reproduction related research questions. Furthermore, it facilitates recontacting for opportunities in treatment development or when diagnose specific trials are started or specific treatment is approved. Conclusion The GeNepher biobank is designed to support a wide range of research projects by providing access to a diverse population of patients with (suspected) MKD and has the potential to make a significant contribution to the field of rare kidney disease research

Cisplatin and carboplatin pharmacokinetics in a pediatric patient with hepatoblastoma receiving peritoneal dialysis

PURPOSE: Cisplatin and carboplatin are frequently used drugs in the treatment of pediatric hepatoblastoma. Dosing guidelines for these drugs in children requiring peritoneal dialysis are lacking. Here, we describe the case of a 3-year-old boy with pre-existing end-stage renal disease on peritoneal dialysis, requiring treatment with cisplatin and carboplatin for hepatoblastoma. METHODS: Pharmacokinetic data were generated to support clinical dosing decisions, with the aim of adequate exposure and minimal toxicity. In the first chemotherapy cycle, 25% of the standard cisplatin dose and 75% of the carboplatin dose, calculated using the pediatric Calvert formula, were administered. Free platinum concentrations were determined in plasma ultrafiltrate and dialysate samples drawn after administration of cis- and carboplatin. RESULTS: Cisplatin was well tolerated and the observed AUC of cisplatin were 15.3 and 14.3 mg/L h in cycles 1 and 3, respectively. The calculated AUC of carboplatin in cycle 1 (9.8 mg/mL min) exceeded target AUC of 6.5 mg/mL min and toxicity was observed; therefore, the dose was reduced in cycles 2 and 3. The observed AUC in cycles 2 and 3 was 5.4 and 5.7 mg/mL min respectively. Platinum concentrations in the dialysate showed that 3-4% of the total dose of cisplatin and 10-12% of the total dose of carboplatin were excreted via peritoneal dialysis. Chemotherapy enabled extended hemihepatectomy and complete remission was achieved. CONCLUSION: This report shows that it is feasible to measure AUCs for both drugs and to individualize the dose of these drugs according to the PK results and clinical parameters. Our advice for future cases would be to calculate the starting dose of carboplatin using the (pediatric) Calvert formula, assuming a dialytic clearance of zero, and to adjust the dose if required, based on therapeutic drug monitoring

Long-term nephrotoxicity in irradiated pediatric kidney tumor survivors: A systematic review

OBJECTIVE: Nephrotoxicity can occur as a side effect after treatment for kidney tumor in childhood. The use of radiotherapy (RT) has a potential additional effect. METHODS: A systematic electronic literature search that combined childhood kidney cancer with different treatments and nephrotoxicity terms was performed in EMBASE. Studies were included based on the reporting of nephrotoxicity occurrence after treatment for kidney tumor during pediatric age, with 75% of participants being under the age of 25 years at the time of diagnosis, and having been treated with any type of kidney surgery, chemotherapy, and/or RT. RESULTS: A pooled analysis did not show significant difference in estimated glomerular filtration rate between the group of patients who received RT compared with the group treated without RT (SMD -0.11 [95% CI -1.07-0.84] p = .733). CONCLUSION: The current literature suggests that the use of RT does not have a significant impact on the decline of kidney function as independent factor

Changes in the urinary extracellular vesicle proteome are associated with nephronophthisis-related ciliopathies

Nephronophthisis is one of the leading genetic causes of end-stage renal disease in childhood. Early diagnostics and prognostics for nephronophthisis are currently limited. We aimed to identify non-invasive protein biomarkers for nephronophthisis in urinary extracellular vesicles. Extracellular vesicles were isolated from urine of 12 patients with a nephronophthisis-related ciliopathy and 12 age- and gender-matched controls, followed by in-depth label-free LC-MS/MS proteomics analysis of gel fractionated extracellular vesicle proteins. Supervised cluster analysis of proteomic profiles separated patients from controls. We identified 156 differentially expressed proteins with fold change ≥4 in patients compared to controls (P <.05). Importantly, expression levels of discriminating proteins were correlated with chronic kidney disease stage, suggesting possible applications for urinary extracellular vesicle biomarkers in prognostics for nephronophthisis. Enrichment analysis of gene ontology terms revealed GO terms including signaling, actin cytoskeleton and endocytosis among the downregulated proteins in patients, whereas terms related to response to wounding and extracellular matrix organization were enriched among upregulated proteins. Our findings represent the first step towards a non-invasive diagnostic test for nephronophthisis. Further research is needed to determine specificity of the candidate biomarkers. In conclusion, proteomic profiles of urinary extracellular vesicles differentiate nephronophthisis-related ciliopathy patients from healthy controls. Significance: Nephronophthisis is an important cause of end-stage renal disease in children and is associated with an average diagnostic delay of 3.5 years. This is the first study investigating candidate biomarkers for nephronophthisis using global proteomics analysis of urinary extracellular vesicles in patients with nephronophthisis compared to control individuals. We show that measuring protein markers in urinary extracellular vesicles is a promising approach for non-invasive early diagnostics of nephronophthisis

The mechanical effects of short-circuit currents in open air substations.

SHort-circuit mechanical effects in substation is investigated by tests and simulations. Simplified equations are deduced to prepare standardisation of a procedure forthe design of substation against short-circuit mechanicle effects

Cellular senescence in kidney biopsies is associated with tubular dysfunction and predicts CKD progression in childhood cancer patients with karyomegalic interstitial nephropathy

Karyomegalic interstitial nephropathy (KIN) has been reported as an incidental finding in patients with childhood cancer treated with ifosfamide. It is defined by the presence of tubular epithelial cells (TECs) with enlarged, irregular, and hyperchromatic nuclei. Cellular senescence has been proposed to be involved in kidney fibrosis in hereditary KIN patients. We report that KIN could be diagnosed 7-32 months after childhood cancer diagnosis in 6/6 consecutive patients biopsied for progressive chronic kidney disease (CKD) of unknown cause between 2018 and 2021. The morphometry of nuclear size distribution and markers for DNA damage (γH2AX), cell-cycle arrest (p21+, Ki67-), and nuclear lamina decay (loss of lamin B1), identified karyomegaly and senescence features in TECs. Polyploidy was assessed by chromosome fluorescence in situ hybridization (FISH). In all six patients the number of p21-positive TECs far exceeded the typically small numbers of truly karyomegalic cells, and p21-positive TECs contained less lysozyme, testifying to defective resorption, which explains the consistently observed low-molecular-weight (LMW) proteinuria. In addition, polyploidy of TEC was observed to correlate with loss of lysozyme staining. Importantly, in the five patients with the largest nuclei, the percentage of p21-positive TECs tightly correlated with estimated glomerular filtration rate loss between biopsy and last follow-up (R 2  = 0.93, p < 0.01). We conclude that cellular senescence is associated with tubular dysfunction and predicts CKD progression in childhood cancer patients with KIN and appears to be a prevalent cause of otherwise unexplained CKD and LMW proteinuria in children treated with DNA-damaging and cell stress-inducing therapy including ifosfamide. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland