Differential effects of insulin-like growth factor binding proteins-1, -2, -3, and -6 on cultured growth plate chondrocytes

Differential effects of insulin-like growth factor binding proteins-1, -2, -3, and -6 on cultured growth plate chondrocytes.BackgroundIn children with chronic renal failure (CRF), impairment of longitudinal growth is in part due to excess amounts of circulating high-affinity insulin-like growth factor binding proteins (IGFBPs) that might decrease or prevent insulin-like growth factor (IGF) binding to its signaling receptor. However, it appears from the clinical studies that various IGFBPs may have contrasting effects on longitudinal growth. Because of the potential importance of the IGFBPs as modulators of longitudinal growth in pediatric CRF, the aim of the present study was to investigate the biological effects of IGFBP-1, -2, -3, and -6 on cultured growth plate chondrocytes that express the type 1 IGF receptor.MethodsThe effects of exogenous IGFBPs on IGF-independent and IGF-dependent proliferation of rat growth plate chondrocytes in primary culture were investigated. Proliferation was assessed by colony formation of agarose-stabilized long-term suspension cultures and by the [3H]thymidine assay. The effects of IGFBPs on IGF-I binding and the binding of IGFBPs to chondrocytes were assessed by binding studies with radiolabeled proteins in monolayer culture.ResultsIntact IGFBP-1, IGFBP-2 and IGFBP-6 inhibited in equimolar concentration the IGF-I- and IGF-II-stimulated DNA synthesis and cell proliferation, whereas the biological activity of IGFBP-3 was complex. It had an IGF-independent antiproliferative effect and also inhibited IGF-dependent chondrocyte proliferation under coincubation conditions, whereas under preincubation conditions IGFBP-3 enhanced IGF-I-responsiveness. Studies on the mechanism by which IGFBP-3 potentiated IGF activity demonstrated that under preincubation conditions IGFBP-3 is capable to associate with the cell membrane and to facilitate IGF-I cell surface binding.ConclusionsIntact IGFBP-1, IGFBP-2 and IGFBP-6 act exclusively as growth inhibitors on IGF-dependent proliferation of growth plate chondrocytes. IGFBP-3, however, can either inhibit IGF-independent and IGF-dependent cell proliferation, or enhance IGF responsiveness of chondrocytes dependent on the temporal relationship to the IGF exposure

Dyslipidaemia in children on renal replacement therapy

Background Information on lipid abnormalities in end-stage renal disease (ESRD) mainly originates from adult patients and small paediatric studies. We describe the prevalence of dyslipidaemia, and potential determinants associated with lipid measures in a large cohort of paediatric ESRD patients. Methods In the ESPN/ERA-EDTA registry, lipid measurements were available for 976 patients aged 2-17 years from 19 different countries from the year 2000 onwards. Dyslipidaemia was defined as triglycerides >100 mg/dL (2-9 years) or >130 mg/dL (9-17 years), high-density lipoprotein (HDL) cholesterol 145 mg/dL. Missing data were supplemented using multiple imputation. Results The prevalence of dyslipidaemia was 85.1% in peritoneal dialysis (PD) patients, 76.1% in haemodialysis (HD) patients and 55.5% among renal allograft recipients. Both low and high body mass index (BMI) were associated with a less favourable lipid profile. Younger age was associated with a worse lipid profile among PD patients. HDL levels significantly improved after transplantation, whereas no significant improvements were found for triglyceride and non-HDL levels. In transplant recipients, use of cyclosporin was associated with significantly higher non-HDL and HDL levels than tacrolimus usage (P 90 mL/min/1.73 m2 (P < 0.0001). Conclusions Dyslipidaemia is common among paediatric ESRD patients in Europe. Young age and PD treatment are associated with worse lipid profiles. Although lipid levels generally improve after transplantation, dyslipidaemia may persist due to decreased graft function, high BMI or to the use of certain immunosuppressant

Outcomes of renal replacement therapy in boys with prune belly syndrome : findings from the ESPN/ERA-EDTA Registry

As outcome data for prune belly syndrome (PBS) complicated by end-stage renal disease are scarce, we analyzed characteristics and outcomes of children with PBS using the European Society for Pediatric Nephrology/European Renal Association-European Dialysis and Transplant Association (ESPN/ERA-EDTA) Registry data. Data were available for 88 male PBS patients aged <20 years who started renal replacement therapy (RRT) between 1990 and 2013 in 35 European countries. Patient characteristics, survival, and transplantation outcomes were compared with those of male patients requiring RRT due to congenital obstructive uropathy (COU) and renal hypoplasia or dysplasia (RHD). Median age at onset of RRT in PBS was lower [7.0; interquartile range (IQR) 0.9-12.2 years] than in COU (9.6; IQR: 3.0-14.1 years) and RHD (9.4; IQR: 2.7-14.2 years). Unadjusted 10-year patient survival was 85% for PBS, 94% for COU, and 91% for RHD. After adjustment for country, period, and age, PBS mortality was similar to that of RHD but higher compared with COU [hazard ratio (HR) 1.96, 95% confidence interval (CI) 1.03-3.74]. Seventy-four PBS patients (84%) received a first kidney transplant after a median time on dialysis of 8.4 (IQR 0.0-21.1) months. Outcomes with respect to time on dialysis before transplantation, chance of receiving a first transplant within 2 years after commencing RRT, and death-censored, adjusted risk of graft loss were similar for all groups. This study in the largest cohort of male patients with PBS receiving RRT to date demonstrates that outcomes are comparable with other congenital anomalies of the kidney and urinary tract, except for a slightly higher mortality risk compared with patients with COU.Peer reviewe

Prediction of High-Grade Vesicoureteral Reflux after Pediatric Urinary Tract Infection: External Validation Study of Procalcitonin-Based Decision Rule

BACKGROUND: Predicting vesico-ureteral reflux (VUR) 653 at the time of the first urinary tract infection (UTI) would make it possible to restrict cystography to high-risk children. We previously derived the following clinical decision rule for that purpose: cystography should be performed in cases with ureteral dilation and a serum procalcitonin level 650.17 ng/mL, or without ureteral dilatation when the serum procalcitonin level 650.63 ng/mL. The rule yielded a 86% sensitivity with a 46% specificity. We aimed to test its reproducibility. STUDY DESIGN: A secondary analysis of prospective series of children with a first UTI. The rule was applied, and predictive ability was calculated. RESULTS: The study included 413 patients (157 boys, VUR 653 in 11%) from eight centers in five countries. The rule offered a 46% specificity (95% CI, 41-52), not different from the one in the derivation study. However, the sensitivity significantly decreased to 64% (95%CI, 50-76), leading to a difference of 20% (95%CI, 17-36). In all, 16 (34%) patients among the 47 with VUR 653 were misdiagnosed by the rule. This lack of reproducibility might result primarily from a difference between derivation and validation populations regarding inflammatory parameters (CRP, PCT); the validation set samples may have been collected earlier than for the derivation one. CONCLUSIONS: The rule built to predict VUR 653 had a stable specificity (ie. 46%), but a decreased sensitivity (ie. 64%) because of the time variability of PCT measurement. Some refinement may be warranted

Phénotype rénal associé aux mutations du gène TCF-2 (HNF-1b) dans la première cohorte pédiatrique

LIMOGES-BU Médecine pharmacie (870852108) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Effets secondaires et efficacité des immunosuppresseurs utilisés dans le traitement du syndrome néphrotique idiopathique chez l'enfant

PARIS-BIUP (751062107) / SudocSudocFranceF

Acute Renal Failure after Abdominal Trauma: Renal Artery Spasm Hypothesis in Ischemic Infarction in a 12-Year-Old Girl

Posttraumatic renal failure is often due to postischemic renal infarction, caused by identified vascular lesions. In our patient, a 12-year-old girl with acute anuric renal failure requiring hemodialysis after severe abdominal trauma, no vascular lesion or thrombosis was identified. Nevertheless, CT-scan and renal biopsy showed typical lesions of diffuse bilateral renal ischemic necrosis. The main hypothesis is a severe bilateral arterial vasospasm after a blunt abdominal trauma. The patient recovered only partially with persisting chronic renal failure

The Role of L-Carnitine in Kidney Disease and Related Metabolic Dysfunctions

Kidney disease is associated with a wide variety of metabolic abnormalities that accompany the uremic state and the state of dialysis dependence. These include altered L-carnitine homeostasis, mitochondrial dysfunctions, and abnormalities in fatty acid metabolism. L-carnitine is essential for fatty acid metabolism and proper mitochondrial function. Deficiency in kidney disease and dialysis is caused by a reduction in endogenous renal synthesis, impaired fatty acid metabolism, a lower intake due to dietary restrictions, and nonselective clearance by the dialysis procedure. Free carnitine levels <40 µmol/L in dialysis patients can lead to dialysis-related complications, such as anemia that is hyporesponsive to erythropoietin therapy, intradialytic hypotension, cardiovascular disease, and skeletal muscle dysfunction manifested as muscle weakness and fatigue. L-carnitine deficiency is also seen in acute kidney injury (AKI) resulting from trauma and/or ischemia, drugs such as cisplatin, and from infections such as covid. A persistent state of L-carnitine deficiency can further damage kidneys and lead to multi-organ failure. Carnitine supplementation has been shown to be safe and effective in improving kidney disease-related complications resulting from drug-induced toxicity, trauma, ischemic injury, infection, and dialysis, by replenishing adequate carnitine levels and rebalancing carnitine homeostasis. In this review, we will examine the protective role of L-carnitine in reducing cellular oxidative damage and maintaining mitochondrial function together with the clinical evidence for its potential use in the management of kidney disease

Secondary Carnitine Deficiency in Dialysis Patients: Shall We Supplement It?

Carnitine, essential for fatty acid β-oxidation, is obtained from diet and through de novo biosynthesis. The organic cation/carnitine transporter 2 (OCTN2) facilitates carnitine cellular transport and kidney resorption. Carnitine depletion occurs in OCTN2-deficient patients, with serious clinical complications including cardiomyopathy, myopathy, and hypoketotic hypoglycaemia. Neonatal screening can detect OCTN2 deficiency. OCTN2-deficiency is also known as primary carnitine deficiency. Carnitine deficiency may result from fatty acid β-oxidation disorders, which are diagnosed via plasma acylcarnitine profiling, but also under other conditions including haemodialysis. Given the importance of the kidney in maintaining carnitine homeostasis, it is not unexpected that longterm haemodialysis treatment is associated with the development of secondary carnitine deficiency, characterised by low endogenous L-carnitine levels and accumulation of deleterious medium and long- chain acylcarnitines. These alterations in carnitine pool composition have been implicated in a number of dialysis-related disorders, including erythropoietin-resistant renal anaemia. The association between erythropoietin resistance and carnitine levels has been demonstrated, with the proportion of medium and long-chain acylcarnitines within the total plasma carnitine pool positively correlated with erythropoietin resistance. Recent research has demonstrated that carnitine supplementation results in a significant reduction in erythropoietin dose requirements in patients with erythropoietin-resistant anaemia. Few studies have been conducted assessing the treatment of carnitine deficiency and haemodialysisrelated cardiac complications, particularly in children. Thus, a study was recently conducted which showed that intravenous carnitine in children receiving haemodialysis significantly increased plasma carnitine

Remission of steroid- and CyA-resistant nephrotic syndrome using multiple drug immunosuppression.

International audienceNephrotic proteinuria in minimal change disease (MCD) is supposed to be due to a circulating factor of immunologic origin. End-stage renal failure occurs if both steroids and immunosuppressive drugs remain ineffective. Three children (2 years, 3 years, and 6 years of age) with secondary steroid-resistant nephrotic syndrome (NS) were included, as they remained resistant to 30 days of treatment with prednisone (60 mg/m(2) per day), three pulses of methylprednisolone (1 g/1.73 m(2)) followed by oral administration of CyA 7.5 mg/kg per day over 2 months, and 1 month of intravenous (i.v.) administration of cyclosporine (blood level 500-600 ng/ml). All three patients were partially responsive to methylprednisolone pulses, with an increase of serum albumin by 100%. They were treated with plasma exchanges, cyclophosphamide and cyclosporine A, both given orally, pefloxacin and methylprednisolone pulses followed by orally administered prednisone. All three patients went into remission within 2 to 5 weeks. The character of their NS changed to a steroid-sensitive one. There were no significant side effects from the therapy. They had normal renal function, normal blood pressure and no residual proteinuria. A combination of plasmapheresis and multiple immunosuppressive medications was effective in producing remission of minimal change NS in three children who were previously resistant to glucocorticoids and cyclosporine