Glomerular Filtration Rate In Young Adults Research Articles

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

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. To develop and validate a modified FAS SCr-based equation combining design features of the FAS and CKD-EPI equations. Cross-sectional analysis with separate pooled data sets for development and validation. Research and clinical studies (n= 13) with measured GFR available. 11251 participants in 7 studies (development and internal validation data sets) and 8378 participants in 6 studies (external validation data set). Clearance of an exogenous marker (reference method), SCr level, age, sex, and height were used to develop a new equation to estimate GFR. The new European Kidney Function Consortium (EKFC) equation is a FAS equation with low bias (-1.2 mL/min/1.73 m2 [95% CI, -2.7 to 0.0 mL/min/1.73 m2] in children and -0.9 mL/min/1.73 m2 [CI, -1.2 to -0.5 mL/min/1.73 m2] in adults) across the FAS (2 to 90 years) and SCr range (40 to 490 µmol/L [0.45 to 5.54 mg/dL]) and with fewer estimation errors exceeding 30% (6.5% [CI, 3.8% to 9.1%] in children and 3.1% [CI, 2.5% to 3.6%] in adults) compared with the CKiD and CKD-EPI equations. No Black patients were included. The new EKFC equation shows improved accuracy and precision compared with commonly used equations for estimating GFR from SCr levels. Swedish Research Council (Vetenskapsrådet).

Estimation of the glomerular filtration rate in children and young adults by means of the CKD-EPI equation with age-adjusted creatinine values

The CKD-EPI creatinine-based estimation equation for glomerular filtration rate (GFR) cannot be used in children, overestimates GFR in young adults, and its combination with the KDIGO recommended pediatric CKiD (Schwartz bedside) equation causes implausible increases in estimated GFR when switching from pediatric to adult care. By establishing sex-specific creatinine growth curves for children and young adults, creatinine levels of children and young adults below age 40 years were adjusted with 40 as assigned age and applied in the CKD-EPI equation. Validation was performed in 4005 children (2-17 years) and 3309 young adults (18-39 years) using metrics based on bias, precision, and accuracy including percentage of estimates within 30% (P30) of measured GFR (mGFR). Comparisons were made with the CKiD and Schwartz-Lyon equations in children. CKD-EPI with age-adjusted creatinine instead of actual age and creatinine led to extensive improvements in bias, precision, and accuracy at all ages, in both sexes and at all levels of mGFR. At mGFR below and above 75 mL/min/1.73m2, the P30 increased from 12% to 75% and 33% to 88% in children, respectively, and from 56% to 73% and 83% to 92% in young adults, respectively. In children adjusted CKD-EPI was more accurate than CKiD, especially above mGFR 75 mL/min/1.73m2 (P30 88% vs. 82%), while Schwartz-Lyon was more accurate than adjusted CKD-EPI at mGFR below 75 mL/min/1.73m2 (P30 81% vs. 75%). Thus, the proposed strategy based on age-adjusted creatinine in children and young adults makes the CKD-EPI equation applicable across the full spectrum of age and kidney function.

Chronic kidney disease in children: An indian perspective

Chronic renal failure (CRF) is an insidious and irreversible condition that eventually progresses to end stage renal failure. It is an important cause of morbidity and mortality in children worldwide. The disease process is better termed as chronic kidney disease (CKD), in order to encompass the entire spectrum and severity of renal disease. In the past various terminologies have been used to describe its severity from chronic renal insufficiency to end stage renal disease (ESRD). This classification did not include the ‘at risk’ population where intervention could modify the outcome. In order to reduce ambiguity and use more objective terms of reference the new name of CKD was introduced. Chronic kidney disease is defined primarily as an abnormality of kidney function or structure as determined by laboratory tests, urinalysis or imaging tests, which have been present for three or more months. Importantly, the classification system describes the stages according to level of estimated glomerular filtration rate (GFR), not serum creatinine levels. This staging uses various clinical, laboratory and imaging parameters [1] and is depicted in Table 1. These stages correspond to the severity of kidney function loss and the prevalence of co-morbidities associated with kidney disease. The identification of low GFR states may allow the implementation of simple measures to prevent worsening. For these reasons, it may be prudent to adopt the system of defining kidney disease according to kidney function, not serum creatinine values. However certain grey areas exist with this classification. The staging takes into consideration normal GFR for a western population. It has been noted that healthy Indians especially on a vegetarian diet have a lower GFR [2]. Secondly, correct interpretation of GFR values in children and adolescents, requires a clear understanding that it varies according to age, gender, and body size. The normal GFR in young adults is 120 to 130 mL/min/1.73 m2, whereas in infancy it is much lower. Even when corrected for body surface area it increases in relationship to body size up to two years. Kidney disease is characteristically asymptomatic and is often not diagnosed until it is relatively advanced. Table 1 Stages of chronic kidney disease