The Glomerular Filtration Rate: From the Diagnosis of Kidney Function to a Public Health Tool

The prevalence of chronic kidney disease (CKD) continues to increase worldwide, as well as the associated morbidity and mortality and the consequences on the patients' quality of life and countries' economies. CKD often evolves without being recognized by patients and physicians, although the diagnosis is based on two simple laboratory data: the estimated glomerular filtration rate (eGFR) and urine analysis. To measure GFR, the knowledge about the physiologic processes at the nephron level, the concept of clearance, and the identification of creatinine as a suitable endogenous marker for measuring the creatinine clearance (CrCl) had to be previously developed. On those bases, different equations to calculate CrCl (Cockcroft and Gault, 1976), or estimated GFR (four variables MDRD, 1999; CKD-Epi, 2009, among others) were generated. They all include creatinine and some demographic data, such as sex and age. However, to compare results throughout life or among laboratories, the creatinine determination must be standardized. In addition, the accuracy of these equations remains controversial in certain subgroups of patients. For these reasons, other mathematical models to improve CrCl estimation have been developed, such as when urine cannot be collected, in debilitated elderly patients and patients with trauma, diabetes, or obesity. Currently, eGFR in adults can be measured and reported immediately, using isotope dilution mass spectrometry traceable creatinine-based equations. In conclusion, based on knowledge obtained from renal physiology, eGFR can be used in the clinic for the diagnosis and early treatment of CKD, as well as a public instrument to estimate the prevalence.

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Assessing glomerular filtration rate in healthy adult potential kidney donors in Bangladesh: A comparison of various prediction equations with measured glomerular filtration rate by diethylentriamine pentaacetic acid renogram

Bangladesh Medical Research Council Bulletin ◽

10.3329/bmrcb.v39i2.19646 ◽

2014 ◽

Vol 39 (2) ◽

pp. 74-79

Author(s):

F Jahan ◽

MNU Chowdhury ◽

T Mahbub ◽

SM Arafat ◽

S Jahan ◽

...

Keyword(s):

Renal Function ◽

Glomerular Filtration Rate ◽

Glomerular Filtration ◽

Filtration Rate ◽

Healthy Adult ◽

Healthy Population ◽

Prediction Equations ◽

Estimated Gfr ◽

Kidney Donors ◽

Measured Gfr

To ensure that potential kidney donors in Bangladesh have no renal impairment, it is extremely important to have accurate methods for evaluating the glomerular filtration rate (GFR). We evaluated the performance of serum creatinine based GFR in healthy adult potential kidney donors in Bangladesh to compare GFR determined by DTPA with that determined by various prediction equations. In this study GFR in 61 healthy adult potential kidney donors were measured with 99mTc-diethylenetriamine penta-acetic acid (DTPA) renogram. We also estimated GFR using a four variable equation modification of diet in renal disease (MDRD), Cockcroft-Gault creatinine clearance (CG CrCl), Cockcroft-Gault glomerular filtration rate (CG-GFR). The mean age of study population was 34.31±9.46 years and out of them 65.6% was male. In this study mean mGFR was 85.4±14.8. Correlation of estimated GFR calculated by CG-CrCl, CG-GFR and MDRD were done with measured GFR DTPA using quartile. Kappa values were also estimated which was found to be 0.104 for (p=0.151), 0.336 for (p=0.001) and 0.125 for (p=0.091) respectively. This indicates there is no association between estimated GFR calculated by CG-CrCl, CG-GFR, MDRD with measured GFR DTPA. These results show poor performance of these equations in evaluation of renal function among healthy population and also raise question regarding validity of these equations for assessment of renal function in chronic kidney disease in our population. DOI: http://dx.doi.org/10.3329/bmrcb.v39i2.19646 Bangladesh Med Res Counc Bull 2013; 39: 74-79

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Glomerular Filtration Rate as a Predictor of Outcome in Acute Coronary Syndrome Complicated by Atrial Fibrillation

Journal of Clinical Medicine ◽

10.3390/jcm9051466 ◽

2020 ◽

Vol 9 (5) ◽

pp. 1466

Author(s):

Domenico Santoro ◽

Guido Gembillo ◽

Giuseppe Andò

Keyword(s):

Atrial Fibrillation ◽

Glomerular Filtration Rate ◽

Glomerular Filtration ◽

Filtration Rate ◽

Cardiovascular Health ◽

Coronary Syndrome ◽

Close Relationship ◽

The Difference ◽

New Onset

The close relationship between kidney and heart is well known. Cardiovascular impairment contributes to the worsening of renal function and kidney failure worsens cardiovascular health. Atrial fibrillation (AF) is a frequent issue in patients with Chronic Kidney Disease (CKD) and several studies have demonstrated that AF impacts negatively on their quality of life and outcomes. Understanding the mechanisms leading to the progression of CKD, new-onset AF and acute myocardial infarction (AMI) is a key issue. The evaluation of Glomerular Filtration Rate (GFR) could make the difference in this equilibrium and suggests specific strategies in the treatment of the population at major risk of cardiovascular events. This intriguing connection paves the way for necessary further investigations.

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Microalbuminuria and Glomerular Filtration Rate in Paediatric Visceral Leishmaniasis

BioMed Research International ◽

10.1155/2013/498918 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4 ◽

Cited By ~ 4

Author(s):

Neena Verma ◽

Chandra Shekhar Lal ◽

Vidyanand Rabidas ◽

Krishna Pandey ◽

Dharmendra Singh ◽

...

Keyword(s):

Glomerular Filtration Rate ◽

Visceral Leishmaniasis ◽

Glomerular Filtration ◽

Filtration Rate ◽

Leishmania Donovani ◽

Renal Involvement ◽

White Blood Cells ◽

Laboratory Data ◽

Urine Examination ◽

Blood And Urine Samples

Visceral leishmaniasis, caused byLeishmania donovani, is a serious form of leishmaniasis and fatal if untreated. Nearly half of the VL cases are children. There are very few studies of renal function in pediatric visceral leishmaniasis. The aim of this study was to evaluate renal dysfunction by studying glomerular filtration rate (GFR), microalbuminuria, and microscopic examination of urine. Laboratory analysis was performed on blood and urine samples of 40 parasitologically confirmed pediatric VL cases. Laboratory data of urine examination showed albuminuria in 10% (4/40), white blood cells in 20% (8/40), hematuria in 10% (4/40), microalbuminuria in 37.5% (15/40), and decreased GFR in 27.5% (11/40). Renal involvement was manifested in most of the pediatric VL cases. These findings may help clinicians in decision making for safe and suitable antileishmanial treatment particularly in childhood VL.

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Association Between Glomerular Filtration Rate And Body Mass Index Among Orthopaedic Patients In Kano-Nigeria

European Scientific Journal ESJ ◽

10.19044/esj.2016.v12n24p130 ◽

2016 ◽

Vol 12 (24) ◽

pp. 130

Author(s):

Adamu SM ◽

Wudil AM ◽

Atiku MK ◽

Alhassan AJ ◽

Ibrahim A ◽

...

Keyword(s):

Body Mass Index ◽

Glomerular Filtration Rate ◽

Glomerular Filtration ◽

Body Mass ◽

Filtration Rate ◽

Demographic Data ◽

Normal Weight ◽

Sample Collection ◽

Orthopaedic Patients ◽

Structured Questionnaire

Any association between body mass index and kidney disease has so far proved inconclusive. Therefore, this study is aimed to provide association between glomerular filtration rate and body mass index among orthopaedic patients. A total of sixty (60) patients irrespective of gender were recruited. Weight and height were measured prior to the sample collection. A structured questionnaire was administered to obtain the demographic data of the subjects. Blood samples were collected from each patient by venepuncture from the antecubital vein of the forearm using disposable syringes. Serum creatinine was determined by method of Rosano et al. Body Mass Index and Glomerular Filtration Rate (eGFR) were calculated using creatinine-based equation of Modification of Diet in Renal Disease. Mean BMI was found to be higher in females (25.48±5.65) than their male counterparts (21.44±4.52), while eGFR was found to be higher in males (184.14±53.23) than in females (152.06±32.71). Subjects with eGFR ≥60 were observed to be more frequent (98.30%); normal weight individuals had higher frequency (48.33%). Positive correlation exists between BMI and eGFR in males whereas negative correlation was found in females which indicates association between body mass index and kidney function is gender related.

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Agreement and Precision Analyses of Various Estimated Glomerular Filtration Rate Formulae in Cancer Patients

Scientific Reports ◽

10.1038/s41598-019-55833-0 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 7

Author(s):

Wiwat Chancharoenthana ◽

Salin Wattanatorn ◽

Somratai Vadcharavivad ◽

Somchai Eiam-Ong ◽

Asada Leelahavanichkul

Keyword(s):

Chronic Kidney Disease ◽

Glomerular Filtration Rate ◽

Glomerular Filtration ◽

Cancer Patients ◽

Filtration Rate ◽

Estimated Glomerular Filtration Rate ◽

Estimated Gfr ◽

Anti Cancer ◽

Precision And Accuracy ◽

Racial Factor

AbstractThe accuracy of the estimated glomerular filtration rate (eGFR) in cancer patients is very important for dose adjustments of anti-malignancy drugs to reduce toxicities and enhance therapeutic outcomes. Therefore, the performance of eGFR equations, including their bias, precision, and accuracy, was explored in patients with varying stages of chronic kidney disease (CKD) who needed anti-cancer drugs. The reference glomerular filtration rate (GFR) was assessed by the 99mTc-diethylene triamine penta-acetic acid (99mTc-DTPA) plasma clearance method in 320 patients and compared with the GFRs estimated by i) the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, ii) the unadjusted for body surface area (BSA) CKD-EPI equation, iii) the re-expressed Modification of Diet in Renal Disease (MDRD) study equation with the Thai racial factor, iv) the Thai eGFR equation, developed in CKD patients, v) the 2012 CKD-EPI creatinine-cystatin C, vi) the Cockcroft-Gault formula, and vii) the Janowitz and Williams equations for cancer patients. The mean reference GFR was 60.5 ± 33.4 mL/min/1.73 m2. The bias (mean error) values for the estimated GFR from the CKD-EPI equation, BSA-unadjusted CKD-EPI equation, re-expressed MDRD study equation with the Thai racial factor, and Thai eGFR, 2012 CKD-EPI creatinine-cystatin-C, Cockcroft-Gault, and Janowitz and Williams equations were −2.68, 1.06, −7.70, −8.73, 13.37, 1.43, and 2.03 mL/min, respectively, the precision (standard deviation of bias) values were 6.89, 6.07, 14.02, 11.54, 20.85, 10.58, and 8.74 mL/min, respectively, and the accuracy (root-mean square error) values were 7.38, 6.15, 15.97, 14.16, 24.74, 10.66, and 8.96 mL/min, respectively. In conclusion, the estimated GFR from the BSA-unadjusted CKD-EPI equation demonstrated the least bias along with the highest precision and accuracy. Further studies on the outcomes of anti-cancer drug dose adjustments using this equation versus the current standard equation will be valuable.

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Performance of the CKD-EPI and MDRD equations to estimate the glomerular filtration rate: a systematic review of Latin American studies

10.21203/rs.2.22162/v1 ◽

2020 ◽

Author(s):

Ana Brañez-Condorena ◽

Sergio Goicochea-Lugo ◽

Jessica Hanae Zafra-Tanaka ◽

Naysha Becerra-Chauca ◽

Virgilio E Failoc-Rojas ◽

...

Keyword(s):

Glomerular Filtration Rate ◽

Glomerular Filtration ◽

Sensitivity And Specificity ◽

Latin American ◽

Filtration Rate ◽

Data Extraction ◽

Isotope Dilution Mass Spectrometry ◽

Grade Methodology ◽

Meta Analyses ◽

Latin American Countries

Abstract BackgroundMost commonly used equations to estimate the glomerular filtration rate (GFR) are the CKD-Epidemiology Collaboration (CKD-EPI) and the Modification of Diet in Renal Disease (MDRD). However, it is not clear which one shows a better performance in Latin America. Objective To assess the performance of both estimated GFR (eGFR) equations in Latin American countries. Methods In January 2019, we performed a systematic search in PubMed, Scopus, and “Biblioteca Regional de Medicina” (BIREME) to identify studies that reported eGFR using CKD-EPI and MDRD equations and compared them with a measured GFR (mGFR) using exogenous filtration markers, among adults from Latin American countries. Study selection, data extraction, and risk of bias evaluation were performed by two reviewers independently. We performed meta-analyses of P30, bias (using mean difference [MD] and its 95% confidence intervals [95% CI]), sensitivity, and specificity; and evaluated certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. Results We included 12 papers, six of them were meta-analyzed (5 from Brazil and 1 from Mexico). Meta-analyses that compared CKD-EPI using creatinine measured with calibration traceable to isotope dilution mass spectrometry (CKD-EPI-Cr IDMS) and MDRD-4 IDMS did not show statistically significant differences in bias (5 studies, MD: 0.55 mL/min/1.73m 2 , 95% CI: -3.34 to 4.44), P30 (2 studies, MD: 4%, 95% CI: -4% to 13%), sensitivity (2 studies, 76% and 75%), and specificity (2 studies, 91% and 89%), with very low certainty of evidence for bias and P30, and low certainty of evidence for sensitivity and specificity. Conclusions We found that the performance of CKD-EPI-Cr IDMS and MDRD-4 IDMS do not differ significantly, although CKD-EPI-Cr IDMS tends to have a non-significant better performance in terms of P30. However, since most of the meta-analyzed studies were from Brazil, results may not be extrapolated to other Latin American countries. Trial registration CRD42019123434, PROSPERO. Registered 18 February 2019.

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Estimating Glomerular Filtration Rate in Black South Africans by Use of the Modification of Diet in Renal Disease and Cockcroft-Gault Equations

Clinical Chemistry ◽

10.1373/clinchem.2007.099085 ◽

2008 ◽

Vol 54 (7) ◽

pp. 1197-1202 ◽

Cited By ~ 79

Author(s):

Hendrick E van Deventer ◽

Jaya A George ◽

Janice E Paiker ◽

Piet J Becker ◽

Ivor J Katz

Keyword(s):

Glomerular Filtration Rate ◽

African Americans ◽

Renal Disease ◽

Glomerular Filtration ◽

Filtration Rate ◽

Estimated Gfr ◽

South Africans ◽

Mdrd Equation ◽

Black South Africans ◽

Measured Gfr

Abstract Background: The 4-variable Modification of Diet in Renal Disease (4-v MDRD) and Cockcroft-Gault (CG) equations are commonly used for estimating glomerular filtration rate (GFR); however, neither of these equations has been validated in an indigenous African population. The aim of this study was to evaluate the performance of the 4-v MDRD and CG equations for estimating GFR in black South Africans against measured GFR and to assess the appropriateness for the local population of the ethnicity factor established for African Americans in the 4-v MDRD equation. Methods: We enrolled 100 patients in the study. The plasma clearance of chromium-51–EDTA (51Cr-EDTA) was used to measure GFR, and serum creatinine was measured using an isotope dilution mass spectrometry (IDMS) traceable assay. We estimated GFR using both the reexpressed 4-v MDRD and CG equations and compared it to measured GFR using 4 modalities: correlation coefficient, weighted Deming regression analysis, percentage bias, and proportion of estimated GFR within 30% of measured GFR (P30). Results: The Spearman correlation coefficient between measured and estimated GFR for both equations was similar (4-v MDRD R2 = 0.80 and CG R2 = 0.79). Using the 4-v MDRD equation with the ethnicity factor of 1.212 as established for African Americans resulted in a median positive bias of 13.1 (95% CI 5.5 to 18.3) mL/min/1.73 m2. Without the ethnicity factor, median bias was 1.9 (95% CI −0.8 to 4.5) mL/min/1.73 m2. Conclusions: The 4-v MDRD equation, without the ethnicity factor of 1.212, can be used for estimating GFR in black South Africans.

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Long-term Prognostic Value for Patients with Chronic Heart Failure of Estimated Glomerular Filtration Rate Calculated with the New CKD-EPI Equations Containing Cystatin C

Clinical Chemistry ◽

10.1373/clinchem.2013.212951 ◽

2014 ◽

Vol 60 (3) ◽

pp. 481-489 ◽

Cited By ~ 18

Author(s):

Elisabet Zamora ◽

Josep Lupón ◽

Marta de Antonio ◽

Joan Vila ◽

Judith Peñafiel ◽

...

Keyword(s):

Heart Failure ◽

Glomerular Filtration Rate ◽

Glomerular Filtration ◽

Cystatin C ◽

Prognostic Value ◽

Filtration Rate ◽

Estimated Glomerular Filtration Rate ◽

Isotope Dilution Mass Spectrometry ◽

Intraclass Correlation ◽

Net Reclassification Improvement

Abstract BACKGROUND Correct estimation of renal function is crucial in assessing prognosis of patients with heart failure (HF). Recently, two new equations have been proposed to calculate estimated glomerular filtration rate (eGFR) with cystatin C alone or both creatinine and cystatin C. We assessed the prognostic value of eGFR estimated by these new equations in outpatients with HF. METHODS The study included 879 patients with median age, 70.4 years; main etiology of HF ischemic heart disease, 52.7%; and median LVEF, 34%. RESULTS eGFR estimates by the new equations correlated significantly with eGFR estimates from previous equations, with the best correlation observed between the 2 equations containing cystatin C [intraclass correlation coefficient 0.95 (95% confidence interval 0.94–0.95)]. During a median follow-up of 3.94 years, 371 patients died. The Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equations containing cystatin C were found to be best for predicting death [area under the ROC curve 0.685 for CKD-EPI-cystatin C and 0.672 for CKD-EPI-creatinine-cystatin C vs 0.632 for simplified Modification of Diet in Renal Disease Study traceable to isotope dilution mass spectrometry and 0.643 for CKD-EPI (all P < 0.001)]. The CKD-EPI-cystatin C equations also showed significantly better calibration and reclassification measurements for both integrated discrimination improvement and net reclassification improvement in predicting death (P < 0.001). Reclassification with these new equations was particularly better in the subgroup with intermediate eGFR [45–74 mL · min−1 · (1.73 m2)−1]. CONCLUSIONS The two new CKD-EPI equations containing cystatin C are useful for HF risk stratification and show better prognostic performance than creatinine-only based eGFR equations, mostly in patients with intermediate eGFR. These equations seem appropriate for assessing prognosis of HF patients with moderate renal insufficiency.

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Glomerular filtration rate: when to measure and in which patients?

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfy363 ◽

2018 ◽

Vol 34 (12) ◽

pp. 2001-2007 ◽

Cited By ~ 6

Author(s):

Rajiv Agarwal ◽

Pierre Delanaye

Keyword(s):

Quality Of Life ◽

Glomerular Filtration Rate ◽

Glomerular Filtration ◽

Filtration Rate ◽

Clinical Decision Making ◽

Population Level ◽

Glomerular Function ◽

Cardiovascular Morbidity And Mortality ◽

Imperfect Knowledge

AbstractOf the glomerular, tubular and endocrine functions of the kidney, nephrologists have mostly focused their attention on the glomerular functions—albuminuria and glomerular filtration rate (GFR)—to grade the severity of chronic kidney disease (CKD). Although both albuminuria and GFR are associated with renal and cardiovascular morbidity and mortality, the utility of measured GFR (mGFR) has been questioned. GFR when measured adequately is the most precise measure of glomerular function and can be useful to individualize therapy among patients with CKD. In situations where estimated GFR is known to provide imprecise estimates of glomerular function, for example, sarcopenia and advanced cirrhosis, the measurement of GFR may be especially important. We discuss several clinical situations where mGFR can potentially influence the quality of life or complications of therapy because of interventions based on imperfect knowledge of GFR. We reason that although large databases may not detect the benefits of mGFR at the population level, precision medicine requires that therapy be individualized based on the best estimate of GFR that can be obtained particularly when the risk of harm is increased. The recent standardization of mGFRs is a step in the right direction and may help in treating the individual patient with CKD with a lower risk of complications and a better quality of life. We call for research in these subgroups of patients where it is clinically felt that mGFR is useful for clinical decision-making.

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On the Basis of Race: The Utility of a Race Factor in Estimating Glomerular Filtration

The Journal of Applied Laboratory Medicine ◽

10.1093/jalm/jfaa128 ◽

2020 ◽

Author(s):

Caroline E Franks ◽

Mitchell G Scott

Keyword(s):

Chronic Kidney Disease ◽

Glomerular Filtration Rate ◽

Glomerular Filtration ◽

Gold Standard ◽

Filtration Rate ◽

Routine Clinical Practice ◽

Kidney Dysfunction ◽

Estimated Gfr ◽

Gold Standard Method ◽

Estimation Equations

Abstract Background Glomerular filtration rate (GFR) is a measure of the combined rate of filtration of all functional nephrons in the kidney. Measurement of GFR is used in the clinic to detect, stratify, and monitor progression of kidney dysfunction, and also serves as a prognostic tool for staging chronic kidney disease (CKD). The gold standard method for measuring GFR is by plasma or urine clearance of exogenous filtration markers, but this is not feasible in routine clinical practice. The most commonly used method to assess GFR is using equations for estimated GFR (eGFR). Content Addition of a race factor to eGFR equations has been recommended to optimize performance for Black individuals. Here, we review the basis of the race-based equation and assess its utility and widespread applicability. Summary Although evidence supporting the performance of a race factor exists in the unique populations in which these estimation equations were derived, more studies are needed to assess the need, or lack thereof, for race factors for all ethnicities. Furthermore, ethnicity is complex and likely cannot be qualified with a 2-level descriptor.

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