Different ways of diagnosing selective glomerular hypofiltration syndromes such as shrunken pore syndrome and the associated increase in mortality.

Background: In 2015, a selective decrease in the glomerular filtration of middle-sized molecules such as cystatin C compared to small molecules such as creatinine was first described and tentatively termed "Shrunken pore syndrome." Numerous studies have thereafter found an association between this syndrome (defined by a low eGFR to eGFR ratio) and mortality and morbidity. In 2023, the syndrome was renamed selective glomerular hypofiltration syndromes (SGHS) as shrunken pores are not the only pathophysiological mechanism.

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.

Diabetic status and the performances of creatinine- and cystatin C-based eGFR equations.

Background And Hypothesis: The estimation of glomerular filtration rate (GFR) is one main tool to detect renal disease. The most used biomarker remains serum creatinine and the European Kidney Function Consortium (EKFCcrea) equation is the most validated in Europe. More recently, cystatin C, has been proposed.

Performance of the European Kidney Function Consortium (EKFC) creatinine-based equation in United States cohorts.

Estimating glomerular filtration rate (GFR) is important in daily practice to assess kidney function and adapting the best clinical care of patients with and without chronic kidney disease. The new creatinine-based European Kidney Function Consortium (EKFC) equation is used to estimate GFR. This equation was developed and validated mainly in European individuals and based on a rescaled creatinine, with the rescaling factor (Q-value) defined as the median normal value of serum creatinine in a given population.

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.

Rescaling creatinine makes GFR estimation equations generally applicable across populations - validation results for the Lund-Malmö equation in a French cohort of sub-Saharan ancestry.

Objectives: To make glomerular filtration rate (GFR) estimating equations applicable across populations with different creatinine generation by using rescaled serum creatinine (sCr/Q) where sCr represents the individual creatinine level and Q the average creatinine value in healthy persons of the same population.

Methods: GFR measurements (mGFR, plasma clearance of Cr-EDTA) were conducted in 964 adult Black Europeans. We established the re-expressed Lund-Malmö revised equation (r-LMR) by replacing serum creatinine (sCr) with rescaled creatinine sCr/Q.

Absolute and relative GFR and contrast medium dose/GFR ratio: cornerstones when predicting the risk of acute kidney injury.

Glomerular filtration rate (GFR) is considered the best overall index of kidney function in health and disease and its use is recommended to evaluate the risk of iodine contrast medium-induced acute kidney injury (CI-AKI) either as a single parameter or as a ratio between the total contrast medium dose (gram iodine) and GFR. GFR may be expressed in absolute terms (mL/min) or adjusted/indexed to body surface area, relative GFR (mL/min/1.73 m).

Revised Swedish guidelines on intravenous iodine contrast medium-induced acute kidney injury 2022: A summary.

The Swedish Society of Uroradiology has revised their computed tomography (CT) guidelines regarding iodine contrast media-induced acute kidney injury (CI-AKI). They are more cautious compared to the European Society of Urogenital Radiology and the American College of Radiology since the actual risk of CI-AKI remains uncertain in patients with moderate to severe kidney damage due to a lack of prospective controlled studies and mainly based on retrospective propensity score-matched studies with low-grade evidence. Another source of uncertainty is the imprecision of glomerular filtration rate (GFR) estimating equations.

Cystatin C-Based Equation to Estimate GFR without the Inclusion of Race and Sex.

Background: The accuracy of estimation of kidney function with the use of routine metabolic tests, such as measurement of the serum creatinine level, has been controversial. The European Kidney Function Consortium (EKFC) developed a creatinine-based equation (EKFC eGFRcr) to estimate the glomerular filtration rate (GFR) with a rescaled serum creatinine level (i.e.

Estimated glomerular filtration rates are higher when creatinine-based equations are compared with a cystatin C-based equation in coronavirus disease 2019.

Objectives: Estimations of glomerular filtration rate (eGFR) are based on analyses of creatinine and cystatin C, respectively. Coronavirus disease 2019 (COVID-19) patients in the intensive care unit (ICU) often have acute kidney injury (AKI) and are at increased risk of drug-induced kidney injury. The aim of this study was to compare creatinine-based eGFR equations to cystatin C-based eGFR in ICU patients with COVID-19.

Standardization of serum creatinine is essential for accurate use of unbiased estimated GFR equations: evidence from three cohorts matched on renal function.

Background: Differences in the performance of estimated glomerular filtration rate (eGFR) equations have been attributed to the mathematical form of the equations and to differences between patient demographics and measurement methods. We evaluated differences in serum creatinine (SCr) and eGFR in cohorts matched for age, sex, body mass index (BMI) and measured GFR (mGFR).

Methods: White North Americans from Minnesota ( = 1093) and the Chronic Renal Insufficiency Cohort (CRIC) ( = 1548) and White subjects from the European Kidney Function Consortium (EKFC) cohort ( = 7727) were matched for demographic patient characteristics (sex, age ± 3 years, BMI ± 2.

Differential Bias for Creatinine- and Cystatin C- Derived Estimated Glomerular Filtration Rate in Critical COVID-19.

COVID-19 is a systemic disease, frequently affecting kidney function. Dexamethasone is standard treatment in severe COVID-19 cases, and is considered to increase plasma levels of cystatin C. However, this has not been studied in COVID-19.

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.

Regarding Iodixanol for Pediatric CTA. Comment on Pop, M. Cardiothoracic CTA in Infants Referred for Aortic Arch Evaluation-Retrospective Comparison of Iomeprol 350, Ioversol 350, Iopromide 370 and Iodixanol 320. 2021, , 949.

With interest, we read the publication 'Cardiothoracic CTA in Infants Referred for Aortic Arch Evaluation-Retrospective Comparison of Iomeprol 350, Ioversol 350, Iopromide 370 and Iodixanol 320' by Pop [...

Evaluation of the creatinine-based chronic kidney disease in children (under 25 years) equation in healthy children and adolescents.

Background: The Chronic Kidney Disease in children (CKiD) equation to estimate glomerular filtration rate eGFR = k × Ht / SCr (Ht = height in cm, SCr = serum creatinine in mg/dL), with fixed k = 0.413, has recently been optimized by introducing age/sex dependent k-values valid for young children up to young adults (the CKiD Under 25 years (CKiDU25) equation). Although the CKiD equation was designed for children with chronic kidney disease (CKD), this equation found common use both clinically and in research, and also in children without CKD.

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.