Estimating glomerular filtration in young people.

Background: Creatinine-based equations are the most used to estimate glomerular filtration rate (eGFR). The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), the re-expressed Lund-Malmö Revised (r-LMR) and the European Kidney Function Consortium (EKFC) equations are the most validated. The EKFC and r-LMR equations have been suggested to have better performances in young adults, but this is debated.

Extending the cystatin C based EKFC-equation to children - validation results from Europe.

Background: A new cystatin C based European Kidney Function Consortium (EKFC) equation was recently developed for adults, using the same mathematical form as the previously published full age spectrum creatinine based EKFC-equation (EKFC). In the present study the cystatin C based EKFC-equation is extended to children, by defining the appropriate cystatin C rescaling factor Q.

Methods: Rescaling factor Q for cystatin C was defined as: a) 0.

Performance of creatinine-based equations to estimate glomerular filtration rate in White and Black populations in Europe, Brazil and Africa.

Background: A new Chronic Kidney Disease Epidemiology Collaboration equation without the race variable has been recently proposed (CKD-EPIAS). This equation has neither been validated outside USA nor compared with the new European Kidney Function Consortium (EKFC) and Lund-Malmö Revised (LMREV) equations, developed in European cohorts.

Methods: Standardized creatinine and measured glomerular filtration rate (GFR) from the European EKFC cohorts (n = 13 856 including 6031 individuals in the external validation cohort), from France (n = 4429, including 964 Black Europeans), from Brazil (n = 100) and from Africa (n = 508) were used to test the performances of the equations.

Preserved renal function during long-term follow-up in children with chronic liver disease.

Aim: We have previously found well-maintained renal function in children with new-onset chronic liver disease. In this study, we investigated their renal function during long-term follow-up of the disease.

Methods: In a study of 289 children with chronic liver disease, renal function was investigated as glomerular filtration rate (GFR) measured as clearance of inulin or iohexol.

Performance of creatinine-based equations to estimate glomerular filtration rate with a methodology adapted to the context of drug dosage adjustment.

Aim: The Cockcroft-Gault (CG) creatinine-based equation is still used to estimate glomerular filtration rate (eGFR) for drug dosage adjustment. Incorrect eGFR may lead to hazardous over- or underdosing.

Methods: In a cross-sectional analysis, CG was validated against measured GFR (mGFR) in 14 804 participants and compared with the Modification-of-Diet-in-Renal-Diseases (MDRD), Chronic-Kidney-Disease-Epidemiology (CKD-EPI), Lund-Malmö-Revised (LMR) and European-Kidney-Function-Consortium (EKFC) equations.

[GFR estimation in children - age-adjusted creatinine makes the adult Lund-Malmö equation applicable in children and facilitates automatic GFR reporting from the clinical laboratory].

Age-adjustment of creatinine, i.e. recalculation of childhood levels of creatinine to corresponding levels at 18 years of age and applied in the adult revised Lund-Malmö GFR equation led to markedly improved accuracy in Swedish children (n=1 718) at measured GFR <75 mL/min/1.

Development and Validation of a Modified Full Age Spectrum Creatinine-Based Equation to Estimate Glomerular Filtration Rate : A Cross-sectional Analysis of Pooled Data.

Background: The Chronic Kidney Disease in Children Study (CKiD) equation for children and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation for adults are recommended serum creatinine (SCr)-based calculations for estimating glomerular filtration rate (GFR). However, these equations, as well as their combination, have limitations, notably the problem of implausible changes in GFR during the transition from adolescence to adulthood and overestimation of GFR in young adults. The full age spectrum (FAS) equation addresses these issues but overestimates GFR when SCr levels are low.

Estimating glomerular filtration rate at the transition from pediatric to adult care.

The current Kidney Disease Improving Global Outcomes (KDIGO) guidelines recommend the use of the bedside creatinine-based Chronic Kidney Disease in Children (CKiD) equation to estimate glomerular filtration rate (GFR) in children and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation in adults. However, this approach causes implausible changes in estimated GFR (eGFR) at the transition from pediatric to adult care. We investigated the performance of the KDIGO strategy and various creatinine-based eGFR equations in a cross-sectional dataset of 5,764 subjects (age 10-30 years), using directly measured GFR (mGFR) as reference.

Validation of standardized creatinine and cystatin C GFR estimating equations in a large multicentre European cohort of children.

Background: Most validations of paediatric glomerular filtration rate (GFR) estimating equations using standardized creatinine (CR) and cystatin C (CYS) assays have comprised relatively small cohorts, which makes accuracy across subgroups of GFR, age, body mass index (BMI) and gender uncertain. To overcome this, a large cohort of children referred for GFR determination has been established from several European medical centres.

Methods: Three thousand four hundred eight measurements of GFR (mGFR) using plasma clearance of exogenous substances were performed in 2218 children aged 2-17 years.

Well Preserved Renal Function in Children With Untreated Chronic Liver Disease.

Objectives: On the basis of studies with hepatorenal syndrome, it is widely regarded that renal function is impacted in chronic liver disease (CLD). Therefore, we investigated renal function in children with CLD.

Methods: In a retrospective study of 277 children with CLD, renal function was investigated as glomerular filtration rate (GFR) and effective renal plasma flow (ERPF), measured as clearance of inulin and para-amino hippuric acid or clearance of iohexol.

Permeation of macromolecules into the renal glomerular basement membrane and capture by the tubules.

How the kidney prevents urinary excretion of plasma proteins continues to be debated. Here, using unfixed whole-mount mouse kidneys, we show that fluorescent-tagged proteins and neutral dextrans permeate into the glomerular basement membrane (GBM), in general agreement with Ogston's 1958 equation describing how permeation into gels is related to molecular size. Electron-microscopic analyses of kidneys fixed seconds to hours after injecting gold-tagged albumin, negatively charged gold nanoparticles, and stable oligoclusters of gold nanoparticles show that permeation into the lamina densa of the GBM is size-sensitive.

Risk factors for progression in children and young adults with IgA nephropathy: an analysis of 261 cases from the VALIGA European cohort.

Background: There is a need for early identification of children with immunoglobulin A nephropathy (IgAN) at risk of progression of kidney disease.

Methods: Data on 261 young patients [age <23 years; mean follow-up of 4.9 (range 2.

New standardized cystatin C and creatinine GFR equations in children validated with inulin clearance.

Background: This study compares glomerular filtration rate (GFR) equations in children based on standardized cystatin C (CYSC) and creatinine (CREA) and their combinations with renal clearance of inulin (C-inulin).

Methods: A total of 220 children with different renal disorders were referred for C-inulin (median 84 ml/min/1.73 m(2)).

Measuring GFR: a systematic review.

Background: No comprehensive systematic review of the accuracy of glomerular filtration rate (GFR) measurement methods using renal inulin clearance as reference has been published.

Study Design: Systematic review with meta-analysis of cross-sectional diagnostic studies.

Setting & Population: Published original studies and systematic reviews in any population.

An observational cohort study of the effect of hypertension on the loss of renal function in pediatric kidney recipients.

Background: Post-transplant hypertension impacts negatively on renal graft survival. Our primary objective was to analyze the effect of hypertension on the glomerular filtration rate (GFR) slope.

Methods: All clinical charts of children who underwent renal transplantation since the introduction of the routine use of ambulatory blood pressure monitoring (ABPM) were reviewed.

Schwartz formula: is one k-coefficient adequate for all children?

Background/objective: Plasma-creatinine-based equations to estimate the glomerular filtration rate are recommended by several clinical guidelines. In 2009, Schwartz et al. adapted the traditional Schwartz equation to children and adolescents but did not find different k-coefficients between children and adolescents (k = 36.

Use of annual ABPM, and repeated carotid scan and echocardiography to monitor cardiovascular health over nine yr in pediatric and young adult renal transplant recipients.

In adult hypertensive patients, increased cIMT and LVH are independent risk factors for cardiovascular events. We have previously observed that in pediatric RTRs with tight control of BP, cIMT did not progress over time. This investigation is an extension of the aforementioned study aimed at re-examining cIMT and also reporting serial echocardiography results.

Renal transplantation in infants and small children.

There are still concerns about renal transplantation in small children. The aim of this study was to identify prenatal data, underlying diseases, patient and graft survival, graft function and growth in young renal transplant recipients at our center. A retrospective analysis was performed on 50 kidney transplants performed during the period 1981-2008 in children weighing <13 kg.