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Purpose: Modification of Diet in Renal Disease' (MDRD) and 'Chronic Kidney Disease Epidemiology Collaboration' (CKD-EPI) formulas are generally accepted and widely utilized tools to assess renal function. In this study, we aimed to investigate the power of the MDRD and CKDEPI formulas, which are the two most used formulas in the measurement of eGFR in patients with multiple myeloma (MM). Materials and Methods: A total of 40 patients, newly diagnosis with MM, were consecutively enrolled to the study and their records were analyzed in terms of demographic features and laboratory parameters of the patients, type of paraproteinemia and stage of disease. MDRD and CKD-EPI formulas were used to evaluate renal function. Results: The difference found between basal and thirdmonth estimated Glomerular Filtration Rate (eGFR) using MDRD (61±15.4 mL/min/1.73 m², third month 75±18.2 mL/min/1.73 m²) and CKD-EPI formulas (62±15.7 mL/min/1.73 m², third month 76±18.4 mL/min/1.73 m²) were significant. There was no significant difference between two formulas regarding basal and third month eGFR mean values. According to CKD staging, 12.5% of all subjects changed and 80% of them moved to better stage. Conclusion: CKD-EPI tends to produce higher eGFR values with compared to MDRD, especially when they are used to evaluate mildly impaired renal function. Hence, prevalence of renal disease was determined lower when assessed with CKD-EPI. Therefore, we recommend that it is important to use the same eGFR estimation formula for a consistent outcomes analysis. [ABSTRACT FROM AUTHOR]

Background and Design: Psoriasis is a common chronic inflammatory skin disease believed to affect renal functions. Glomerular filtration rate (GFR) is the most important indicator used to assess renal functions. The present study aims to measure the renal function of psoriasis patients via the technetium-99m diethylenetriamine pentaacetate (Tc-99m DTPA) method and compare the values obtained with those determined through indirect measurement methods, such as the modification of diet in renal disease (MDRD) and chronic kidney disease epidemiology collaboration (CKD-EPI), considering the effects of systemic treatments and comorbidities. Materials and Methods: Eighty-seven patients diagnosed with chronic plaque-type psoriasis vulgaris were included in this study. The patients’ demographic characteristics, disease duration, psoriasis area and severity index score, drugs received for psoriasis treatment, comorbidities, and drugs received for comorbidity treatment were noted. Estimated GFRs were also calculated using the MDRD and CKD-EPI formulas. Results: Tc-99m DTPA values were affected only by age. As the patient age increased, a significant decrease in GFR measured with Tc-99m DTPA (r=0.289, p

Background: Carboplatin is the backbone cytotoxic agent for many chemotherapy regimens for lung cancer. Dosing of carboplatin is complicated due to its relationship to renal function and narrow therapeutic index. Overestimation of renal function may lead to supratherapeutic dosing and toxicity, while underestimation may lead to underdosing and therapeutic failure. Although the Modification of Diet in Renal Disease (MDRD) and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations have higher accuracy in estimating glomerular filtration rate (eGFR), the Cockcroft Gault (CG) formula has been historically used for carboplatin dosing internationally.Methods: We compared these formulae to identify patient profiles that were associated with significant carboplatin dose variation by retrospectively analysing the carboplatin dosing of 96 patients with lung cancer. Carboplatin doses were calculated using eGFR generated by MDRD, CKD-EPI 2009 and CKD-EPI 2021 equations. These three hypothetical doses were compared to actual CG-based doses prescribed.Results: MDRD and CKD-EPI equations resulted in comparable carboplatin doses; however, CG doses diverged markedly with up to 17% of the patients receiving a carboplatin dose that was at least 20% higher than a non-CG formula would have predicted, and 20% received a dose that was at least 20% lower than a non-CG formula would have predicted. Our data suggest CG use overestimates kidney function in patients with a higher bodyweight and body surface area (BSA) while underestimating it in patients with a lower bodyweight and BSA. Importantly, we demonstrate potential real-world benefit as CKD-EPI predicted lower doses for patients whose (CG-derived) carboplatin dose was later reduced following clinical assessment prior to infusion.Conclusions: We have therefore confirmed significant differences in carboplatin dosing depending on the equation used in our modern patient population and suggest that use of CKD-EPI provides the most clinically appropriate carboplatin dosing and should be implemented as the new standard of care internationally. [ABSTRACT FROM AUTHOR]

Abstract Background To determine the prevalence, distribution, concordance and associations of chronic kidney disease (CKD) determined by five glomerular filtration rate (GFR) formulae in urban black residents of Cape Town. Methods Data collection in this cross-sectional study included interviews, clinical measurements and biochemical analyses, including serum creatinine and cystatin C levels. GFR was based on the CKD Epidemiology Collaboration (CKD-EPI) equations (CKD-EPI creatinine (CKD-EPIcr), CKD-EPI cystatin C (CKD-EPIcys), CKD-EPI creatinine-cystatins (CKD-EPIcr-cys)), Modification of Diet in Renal Disease (MDRD) and Cockcroft-Gault formula (CGF). GFR

ABSTRACT: Background: Standard equations for estimating glomerular filtration rate (eGFR) employ race multipliers, systematically inflating eGFR for Black patients. Such inflation is clinically significant because eGFR thresholds of 60, 30, and 20 ml/min/1.73m2 guide kidney disease management. Racialized adjustment of eGFR in Black Americans may thereby affect their clinical care. In this study, we analyze and extrapolate national data to assess potential impacts of the eGFR race adjustment on qualification for kidney disease diagnosis, nephrologist referral, and transplantation listing. Methods: Using population-representative cross-sectional data from the United States National Health and Nutrition Examination Survey (NHANES) from 2015-2018, eGFR values for Black Americans were calculated using the Modification of Diet in Renal Disease (MDRD) equation with and without the 1.21 race-specific coefficient using cohort data on age, sex, race, and serum creatinine. Findings: Without the MDRD eGFR race adjustment, 3.3 million (10.4%) more Black Americans would reach a diagnostic threshold for Stage 3 Chronic Kidney Disease, 300,000 (0.7%) more would qualify for beneficial nephrologist referral, and 31,000 (0.1%) more would become eligible for transplant evaluation and waitlist inclusion. Interpretation: These findings suggest eGFR race coefficients may contribute to racial differences in the management of kidney. We provide recommendations for addressing this issue at institutional and individual levels. Funding: No external funding was received for this study.

Background: Numerous equations are used to estimate glomerular filtration rate (eGFR), based on serum creatinine (SCr), demographic and anthropometric data, none established in pediatric kidney transplant recipients. This study aimed to validate the available SCr-based eGFR equations in comparison with a measured (mGFR), stratified by chronic kidney disease (CKD) stage and age at the time of testing. Methods: One hundred twenty-seven pediatric kidney transplant recipients with 411 mGFR values (plasma clearance of iothalamate) were enrolled in this retrospective study. The bias, precision, and accuracy (percentage of estimates within 10% and 30% of mGFR) of five SCr eGFR equations (original Schwartz, CKiDSCr equation, Pottel, Modification of Diet in Renal Disease (MDRD), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI)) were assessed. Results: Height-independent Pottel equation performed well across all the categories of age and CKD staging. CKiDSCr equation performed well in CKD stages II–V. The CKiDSCr equation had a lower bias in children < 15 years of age, while MDRD and CKD-EPI equations had less bias in children > 15 years. Overall, both the Pottel and CKiDSCr equations had high accuracy (80%) and low bias (< 5 ml/min/1.73 m2). In contrast, the original Schwartz, MDRD, and CKD-EPI equations displayed high bias and low precision/accuracy. Conclusions: Given their low bias and high accuracy across ages and CKD stages, the Pottel or the CKiDSCr equation is better to assess eGFR in pediatric kidney transplant recipients. The Pottel equation outperformed other eGFR equations in adolescents. [ABSTRACT FROM AUTHOR]

• We removed the race correction factor from eGFR while moving from MDRD to CKD-EPI. • Reclassification rates were determined for our patient population. • Distributions of eGFR without race were similar in Black and non-Black patients. Creatinine-based MDRD and CKD-EPI equations include a race correction factor, which results in higher eGFR in Black patients. We evaluated the impact on our patient population upon adoption of the CKD-EPI equation and the removal of the race correction factor from the equation. Retrospective analysis of blood creatinine results and respective eGFR values calculated by the MDRD or CKD-EPI equation without the race correction factor (CKD-EPI NoRace) in a large academic medical system over a 20.5-month period. In our population, when changing from MDRD to CKD-EPI NoRace , we observed that 3.5% of all patients were reclassified to categorically have worse kidney function. However, we also observed fewer patients overall with eGFR below 60 mL/min/1.73 m2. Around 60 and 20 mL/min/1.73 m2, 2.96% and 0.16% of all patients > 65 years of age were reclassified, as were 4.29% and 0.03% of all Black patients, respectively. When calculated with CKD-EPI NoRace , median eGFR was not meaningfully different between Black and non-Black patients (p = 0.02). Changing from MDRD to CKD-EPI NoRace could lead to a lower referral rate to nephrology. The distributions of creatinine and eGFR calculated with CKD-EPI NoRace were not meaningfully different in Black and non-Black patients. [ABSTRACT FROM AUTHOR]

Background and Design: Psoriasis is a common chronic inflammatory skin disease believed to affect renal functions. Glomerular filtration rate (GFR) is the most important indicator used to assess renal functions. The present study aims to measure the renal function of psoriasis patients via the technetium-99m diethylenetriamine pentaacetate (Tc-99m DTPA) method and compare the values obtained with those determined through indirect measurement methods, such as the modification of diet in renal disease (MDRD) and chronic kidney disease epidemiology collaboration (CKD-EPI), considering the effects of systemic treatments and comorbidities. Materials and Methods: Eighty-seven patients diagnosed with chronic plaque-type psoriasis vulgaris were included in this study. The patients' demographic characteristics, disease duration, psoriasis area and severity index score, drugs received for psoriasis treatment, comorbidities, and drugs received for comorbidity treatment were noted. Estimated GFRs were also calculated using the MDRD and CKD-EPI formulas. Results: Tc-99m DTPA values were affected only by age. As the patient age increased, a significant decrease in GFR measured with Tc-99m DTPA (r=0.289, p<0.001) was observed. Conclusion: Psoriasis, comorbidities, and nephrotoxic drugs used for treatment did not affect renal functions. GFR measurements were affected only by age. [ABSTRACT FROM AUTHOR]

Abstract Objectives This study validates two popular predictive equations of renal function firstly, Modifications of Diet in Renal Disease and secondly, Chronic Kidney Disease Epidemiology Collaboration equations for Sri Lankan cohort. We used data of the patients referred to Renal Research lab of University of Colombo for creatinine clearance measurement. Results Predictive performances varied with the gender. Creatinine clearance and predicted renal functions were compared. Both fared unsatisfactorily with R2 ranging from 0.632 to 0.652, and overestimated renal function by 6–15%. The proportion chronic kidney disease staging 1 and 2 returned by Chronic Kidney Disease Epidemiology Collaboration equation showed significant difference, in females. Modifications of Diet in Renal Disease equation significantly under-estimated advanced chronic kidney disease in females. Chronic Kidney Disease Epidemiology Collaboration equation had better accuracy. The study sample had more females, Asian and lower body size and better renal functions than historic cohorts. Thai and Pakistani studies show both equations and their Asian adaptations fare poorly. Chronic kidney disease stages differ significantly with the equation used. Predictive equations have fared unsatisfactorily by overestimating renal functions. We recommend further studies using gold standards of measuring renal function.

Introduction: Measuring glomerular filtration rate (GFR) with the isotopic method is a gold standard. However, it is an elaborate and expensive procedure, so in everyday practice GFR is estimated with creatinine-based formulas. Despite the number of studies, it remains unclear which GFR estimating equation is the most accurate, especially in increasing elderly population. Aim: The aim of this study was to compare the commonly used formulas to assess which one of them should be used in elderly female non-diabetic patients suffering from chronic kidney disease (CKD). Material and methods : 336 non-diabetic females aged 70 and more were qualified to the study. On the basis of serum creatinine concentration, estimated GFR (eGFR) was estimated using various formulas. Results and discussions: The eGFR and CKD stages differ significantly depending on the used formula. The modification of diet in renal disease equation (MDRD) formula showed slightly, but still significantly, better correlation with creatinine concentration in serum than the CKD epidemiology collaboration equation. The Cockcroft-Gault equation formula was significantly inferior to above mentioned equations. The receiver operating characteristic curves showed that MDRD is the most sensitive equation and the differences between formulas compared in pairs were significant. Conclusions : Due to its highest correlation with creatinine and its highest sensitivity and specificity, the MDRD formula seems to be the most accurate equation to estimate GFR in elderly non-diabetic females. [ABSTRACT FROM AUTHOR]

Copyright of Revista Médica de Rosario is the property of Circulo Medico de Rosario and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Direct oral anticoagulants (DOACs) are widely prescribed nowadays. Available DOACs are renally eliminated to some extent and need dose adjustment in patients with kidney dysfunction. Cockcroft-Gault (CG) formula has been used to estimate creatinine clearance in DOACs trials. Nowadays, Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) are preferred equations for estimating glomerular filtration rate (GFR). We reviewed studies that simulated DOACs dosing in patients with atrial fibrillation by MDRD, CKD-EPI, and CG. DOACs dose discordance varies from 28.8% underdosing to 59.2% overdosing when MDRD or CKD-EPI equations are substituted for CG. MDRD and CKD-EPI overestimate the GFR in lower thresholds of kidney function especially in elderly and females and result in overestimation of DOACs dosing or misclassifying the patients to be eligible for receiving DOACs when they are contraindicated. Compared with CG, MDRD and CKD-EPI underestimate the level of kidney function in higher GFR extremes and in these patients suggest DOACs when they are not recommended or suggest lower doses. Until running large clinical studies on efficacy/safety of DOACs dosing using MDRD or CKD-EPI equations, use of CG method for DOACs dosing is recommended in real practice. [ABSTRACT FROM AUTHOR]

Copyright of Nefrologia is the property of Revista Nefrologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background The most commonly used glomerular filtration rate estimating equations for drug dosing are Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. However there is still a concern about whether to use MDRD and CKD-EPI interchangeably with CG for drug dosage adjustment. Methods The study was initiated to determine the concordance between MDRD, CKD-EPI and CG equations and associated factors in patients with chronic kidney disease at Saint Paul’s Hospital Millennium Medical College (SPHMMC). This was a cross sectional study which involved patient chart review and physicians self-administered questionnaire. Serum creatinine level ≥ 1.2 mg/dL was used as a cutoff point in pre-selection of patients. The correctness of the drug dose prescribed for the level of renal function were compared to the drug database (Lexi-Comp) available through Up-to-date version 21.2. Results Among the total of 422 patients, 249 (59%) were males. Mean age of patients was 46.09 years. The use of MDRD equation for drug dose adjustment by physicians working in the renal clinic of SPHMMC was six out of nine physicians. The Pearson correlation coefficient between the CG with MDRD and CKD-EPI equations was r = 0.94, P 70 years was associated with discordance between CG and MDRD equations for drug dosing recommendation whereas serum creatinine 1.2–3.5 mg/dL, weight 70 years were associated with discordance between the CG with MDRD and CKD-EPI equations for FDA assigned kidney function categories. However, none of the factors associated with discordance between CG and CKD-EPI for drug dosing. Conclusion MDRD equation can be used interchangeably with CG equation for drug dosing recommended in all adult patients between the age of 18 and 70 years. CKD-EPI can be used interchangeably with CG in all adult Ethiopian patients with CKD.

Abstract Background Accurate measurement of renal function is important: however, radiolabelled gold standard measurement of GFR is highly expensive and can only be used on a very limited scale. We aim to compare the performance of Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equations in the multi-ethnic population attending University Malaya Medical Centre (UMMC). Methods This is a cross-sectional study recruiting patients, who attend UMMC Nephrology clinics on voluntary basis. 51-Chromium EDTA (51Cr-EDTA) plasma level was used to measure the reference GFR. The serum creatinine was determined by IDMS reference modified Jaffe kinetic assay (CrJaffe). The predictive capabilities of MDRD and CKD-EPI based equations were calculated. Data was analysed using SPSS version 20 and correlation, bias, precision and accuracy were determined. Results A total of 113 subjects with mean age of 58.12 ± 14.76 years and BMI of 25.99 ± 4.29 kg/m2 were recruited. The mean reference GFR was 66.98 ± 40.65 ml/min/1.73m2, while the estimated GFR based on MDRD and CKD-EPI formula were 62.17 ± 40.40, and 60.44 ± 34.59, respectively. Both MDRD and CKD-EPI were well-correlated with reference GFR (0.806 and 0.867 respectively) and statistically significant with p

Abstract Background Several equations have been developed to estimate glomerular filtration rate (eGFR). The common equations used were derived from populations predominantly comprised of Caucasians with chronic kidney disease (CKD). Some of the equations provide a correction factor for African-Americans due to their relatively increased muscle mass and this has been extrapolated to black Africans. Studies carried out in Africa in patients with CKD suggest that using this correction factor for the black African race may not be appropriate. However, these studies were not carried out in healthy individuals and as such the extrapolation of the findings to an asymptomatic black African population is questionable. We sought to compare the proportion of asymptomatic black Africans reported as having reduced eGFR using various eGFR equations. We further compared the association between known risk factors for CKD with eGFR determined using the different equations. Methods We used participant and laboratory data collected as part of a global reference interval study conducted by the Committee of Reference Intervals and Decision Limits (C-RIDL) under the International Federation of Clinical Chemistry (IFCC). Serum creatinine values were used to calculate eGFR using the Cockcroft-Gault (CG), re-expressed 4 variable modified diet in renal disease (4v–MDRD), full age spectrum (FAS) and chronic kidney disease epidemiology collaboration equations (CKD-EPI). CKD classification based on eGFR was determined for every participant. Results A total of 533 participants were included comprising 273 (51.2%) females. The 4v–MDRD equation without correction for race classified the least number of participants (61.7%) as having an eGFR equivalent to CKD stage G1 compared to 93.6% for CKD-EPI with correction for race. Only age had a statistically significant linear association with eGFR across all equations after performing multiple regression analysis. The multiple correlation coefficients for CKD risk factors were higher for CKD-EPI determined eGFRs. Conclusions This study found that eGFR determined using CKD-EPI equations better correlated with a prediction model that included risk factors for CKD and classified fewer asymptomatic black Africans as having a reduced eGFR compared to 4v–MDRD, FAS and CG corrected for body surface area.

Although environmental exposure to multiple metals is common, epidemiological studies on the associations of exposure to 23 metals with kidney function have not been analyzed. We aimed to investigate the associations of 23 metals levels with renal function. We conducted a cross-sectional study in four rural regions of Hunan province. Plasma and urine metals levels were determined by inductively coupled plasma mass spectrometer (ICP-MS). Two-level logistic regression was used to investigate the associations of metals levels with estimated glomerular filtration rate (eGFR) with adjustment for confounding factors. We conducted a sensitivity analysis of the results using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. A total of 3553 participants completed the investigation. Five metals (plasma arsenic and molybdenum; urine copper, rubidium, and strontium) were identified to be significantly associated with renal function. Participants in the highest quartile of plasma arsenic and molybdenum were at 17.95 (95% CI: 6.35–50.76) and 24.23 (95% CI: 7.42–79.19) fold risk of abnormal eGFR, respectively, compared with the lowest quartile. The highest quartiles of urine copper, rubidium, and strontium were associated with 3.70 (95% CI:1.92–7.14), 0.16 (95% CI:0.07–0.37) and 0.08 (95% CI: 0.03–0.21) fold risk of abnormal eGFR. The sensitivity analysis revealed that plasma arsenic, molybdenum and urine copper, rubidium and strontium levels retained similar associations with abnormal eGFR. Plasma arsenic and molybdenum, and urine copper are risk factors for abnormal renal function, while urine rubidium and strontium are protective factors for renal function. • A cross-sectional study was conducted in four rural regions of Hunan province. • The associations of multiple metal levels with renal function was investigated. • Multiple metals in plasma and urine are associated with abnormal eGFR. [ABSTRACT FROM AUTHOR]

Renal function is the most commonly applied patient‐specific quantitative variable used to determine drug doses. Measurement of renal function is not practical in most clinical settings; therefore, clinicians often rely on estimates when making dosing decisions. Similarly, renal function estimates are used to assign subjects in phase 1 pharmacokinetic studies, which inform dosing in late‐phase clinical trials and ultimately the product label. The Cockcroft‐Gault estimate of creatinine clearance has been the standard renal function metric; however, this paradigm is shifting toward the Modification of Diet in Renal Diseases (MDRD) estimate of the glomerular filtration rate (GFR). The proportion of approved new drug labels with dosing recommendations based on the MDRD equation was 16.7% in 2015, 70.0% in 2016, and 46.7% in 2017. Disharmonious recommendations from the United States Food and Drug Administration and the European Medicines Agency will continue to increase this heterogeneity in the assessment of renal function in drug development and negatively impact industry, health systems, and clinicians. In this review, we discuss the current regulatory guidance for the conduct of renal impairment pharmacokinetic studies and review the implications of this guidance across the medication use system with 3 recently approved antibiotics: ceftazidime/avibactam, delafloxacin, and meropenem/vaborbactam. Finally, we suggest measuring GFR in phase 1 studies and employing the Chronic Kidney Disease Epidemiology Collaboration (CKD‐EPI) equation to integrate data across clinical trials. This will help to harmonize CKD staging, population pharmacokinetic analyses, and dosing by estimated renal function. [ABSTRACT FROM AUTHOR]

Background: The evaluation of chronic kidney disease (CKD) in cancer patients seems to rely mostly on the Cockcroft‐Gault (CG) formula or the creatinine levels to adjust treatment dosages which is a practice refuted by internists. Aims: We evaluate the overall agreement of the CG, modification of diet in renal disease (MDRD) and CKD–epidemiology collaboration equations (CKD‐EPI) equation with the newly devised Janowitz and Williams' (JW) equation. Methods: The renal function was estimated in 235 cancer patients according to the CG, MDRD, body surface area (BSA)‐adjusted MDRD, CKD‐EPI, BSA‐adjusted CKD‐EPI and JW formulae. Results: JW equation was more in agreement with CG and CKD‐EPI estimations than the other equations. Taking JW equation as reference, receiver operating characteristic curve analysis showed that CG eGFR had the higher area under the curve when compared with other equations. Hierarchical cluster analysis showed more proximity between CG and JW equations than the other equations. Conclusion: The newly proposed JW eGFR estimation was more in agreement with CG equation than the other equations. [ABSTRACT FROM AUTHOR]

Background/Aims: Accurate staging of chronic kidney disease (CKD) is very important. We tried to identify difference in GFR evaluation between CKD-EPI and Gates method with renal scintigraphy and which variables are associated with these differences. Methods: We retrospectively reviewed the records of 341 patients who underwent dynamic renal scintigraphy in the last 5 years. Patients were categorized according to KDIGO staging I to V, using the eGFR calculated with the CKD-EPI equation. Secondarily, we stratified patients according to treatment with renin-angiotensin system (RAS) inhibitors. Results: Gates method tends to underestimate GFR especially in CKD stage I (mean -22.2 ml/min) and II (mean -12.5 ml/min). The division in quartiles of ages showed an underestimation of GFR only in the first quartile of age (Conclusion: The assessment of GFR by the Gates method must be carefully considered in the early stages of CKD, especially in younger patients. Moreover, the difference is more pronounced in patients treated with RAS inhibitors. Longitudinal studies will prove which method better predicts cardiovascular or renal events.

Background The estimation of glomerular filtration rate (GFR) plays a vital role in assessment of the renal function. This study evaluated the performance of the CKD-EPI creat and MDRD equations in the South African Kwa-Zulu Natal population. Objectives The objectives if the study were to compare the of CKD-EPI creat and MDRD equations in the selected population to the measured GFR using Sodium Technetium-99 m-diethylene-triamine-pentaacetate clearance derived GFR. Method Records of adult patients with measured GFR performed at the Nuclear Medicine Department at Inkosi Albert Luthuli Central Hospital, Durban, South Africa from 1 April 2014 to 31 March 2016 were reviewed. eGFR for all included patients was calculated using the MDRD equation without African American correction factor and the CKD-EPI creat equation with and without the African American correction factor for the Black African patients. Statistical comparison of the eGFR with measured GFR was performed with Bland Altman bias plots, Wilcoxon match pairs signed ranks test and accuracy within 10% and 30%.ROC curve analysis assessed the sensitivity and specificity at eGFR <90 and < 60 ml/min/1.73m 2 . Results After exclusion, 287 patients were included for analysis with sufficient numbers for only the Black African and Indian patients. None of the equations showed accuracy of eGFR within 30% of measured GFR for 90% of patients. In the Black African population, the CKD-EPI creat equation without the correction factor performed best. 17% and 14.4% of the Black African participants would be reclassified with the CKD-EPI creat equation without and with the African American correction factor respectively compared to mGFR at a cut-off of 60 mls/min/1.73m 2 . Conclusion None of the evaluated equations attained the 2002 KDOQI benchmark of P 30 >90%. 11.1–17% of individuals would have been incorrectly classified using the CKD-EPI creat equation. [ABSTRACT FROM AUTHOR]

Background: Chronic kidney disease (CKD) is diagnosed using the estimated glomerular filtration rate (eGFR) and the urinary albumin:creatinine ratio (ACR). The eGFR is calculated from serum creatinine levels using the Modification of Diet in Renal Disease (MDRD) or Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations.Aim: To compare the performance of one versus two eGFR/ACR measurements, and the impact of equation choice, on CKD diagnosis and classification.Design and Setting: Cohort study in primary care in the Thames Valley region of the UK.Method: Data were from 485 participants aged >60 years in the Oxford Renal Cohort Study with at least two eGFR tests. The proportion of study participants diagnosed and classified into different CKD stages using one and two positive tests were compared. Prevalence of CKD diagnosis and classification by CKD stage were compared when eGFR was calculated using MDRD and CKD-EPI equations.Results: Participants included in the analysis had a mean age of 72.1 (±6.8) years and 57.0% were female. Use of a single screening test overestimated the proportion of people with CKD by around 25% no matter which equation was used, compared with the use of two tests. The mean eGFR was 1.4 ml/min/1.73 m2 (95% CI = 1.1 to 1.6) higher using the CKD-EPI equation compared with the MDRD equation. More patients were diagnosed with CKD when using the MDRD equation, compared with the CKD-EPI equation, once (64% versus 63%, respectively) and twice (39% versus 38%, respectively), and 16 individuals, all of who had CKD stages 2 or 3A with MDRD, were reclassified as having a normal urinary ACR when using the CKD-EPI equation.Conclusion: Current guidance to use two eGFR measures to diagnose CKD remains appropriate in an older primary care population to avoid overdiagnosis. A change from MDRD to CKD-EPI equation could result in one in 12 patients with a CKD diagnosis with MDRD no longer having a diagnosis of CKD. [ABSTRACT FROM AUTHOR]

Background: Several equations have been developed to estimate glomerular filtration rate (eGFR). The common equations used were derived from populations predominantly comprised of Caucasians with chronic kidney disease (CKD). Some of the equations provide a correction factor for African-Americans due to their relatively increased muscle mass and this has been extrapolated to black Africans. Studies carried out in Africa in patients with CKD suggest that using this correction factor for the black African race may not be appropriate. However, these studies were not carried out in healthy individuals and as such the extrapolation of the findings to an asymptomatic black African population is questionable. We sought to compare the proportion of asymptomatic black Africans reported as having reduced eGFR using various eGFR equations. We further compared the association between known risk factors for CKD with eGFR determined using the different equations.Methods: We used participant and laboratory data collected as part of a global reference interval study conducted by the Committee of Reference Intervals and Decision Limits (C-RIDL) under the International Federation of Clinical Chemistry (IFCC). Serum creatinine values were used to calculate eGFR using the Cockcroft-Gault (CG), re-expressed 4 variable modified diet in renal disease (4v-MDRD), full age spectrum (FAS) and chronic kidney disease epidemiology collaboration equations (CKD-EPI). CKD classification based on eGFR was determined for every participant.Results: A total of 533 participants were included comprising 273 (51.2%) females. The 4v-MDRD equation without correction for race classified the least number of participants (61.7%) as having an eGFR equivalent to CKD stage G1 compared to 93.6% for CKD-EPI with correction for race. Only age had a statistically significant linear association with eGFR across all equations after performing multiple regression analysis. The multiple correlation coefficients for CKD risk factors were higher for CKD-EPI determined eGFRs.Conclusions: This study found that eGFR determined using CKD-EPI equations better correlated with a prediction model that included risk factors for CKD and classified fewer asymptomatic black Africans as having a reduced eGFR compared to 4v-MDRD, FAS and CG corrected for body surface area. [ABSTRACT FROM AUTHOR]

Background: The most commonly used glomerular filtration rate estimating equations for drug dosing are Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. However there is still a concern about whether to use MDRD and CKD-EPI interchangeably with CG for drug dosage adjustment.Methods: The study was initiated to determine the concordance between MDRD, CKD-EPI and CG equations and associated factors in patients with chronic kidney disease at Saint Paul's Hospital Millennium Medical College (SPHMMC). This was a cross sectional study which involved patient chart review and physicians self-administered questionnaire. Serum creatinine level ≥ 1.2 mg/dL was used as a cutoff point in pre-selection of patients. The correctness of the drug dose prescribed for the level of renal function were compared to the drug database (Lexi-Comp) available through Up-to-date version 21.2.Results: Among the total of 422 patients, 249 (59%) were males. Mean age of patients was 46.09 years. The use of MDRD equation for drug dose adjustment by physicians working in the renal clinic of SPHMMC was six out of nine physicians. The Pearson correlation coefficient between the CG with MDRD and CKD-EPI equations was r = 0.94, P < 0.001 and r = 0.95, P < 0.001, respectively. The concordance between the CG with MDRD and CKD-EPI equations for FDA assigned kidney function categories was 73.7%, Kappa = 0.644 and 74.9%, Kappa = 0.659, respectively. Concordance between the CG with MDRD and CKD-EPI equations for the drug dosing recommendation was 89.6%, kappa = 0.782 and 92%, kappa = 0.834, respectively. Age > 70 years was associated with discordance between CG and MDRD equations for drug dosing recommendation whereas serum creatinine 1.2-3.5 mg/dL, weight < 61 Kg and age > 70 years were associated with discordance between the CG with MDRD and CKD-EPI equations for FDA assigned kidney function categories. However, none of the factors associated with discordance between CG and CKD-EPI for drug dosing.Conclusion: MDRD equation can be used interchangeably with CG equation for drug dosing recommended in all adult patients between the age of 18 and 70 years. CKD-EPI can be used interchangeably with CG in all adult Ethiopian patients with CKD. [ABSTRACT FROM AUTHOR]

Background: Accurate measurement of renal function is important: however, radiolabelled gold standard measurement of GFR is highly expensive and can only be used on a very limited scale. We aim to compare the performance of Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equations in the multi-ethnic population attending University Malaya Medical Centre (UMMC).Methods: This is a cross-sectional study recruiting patients, who attend UMMC Nephrology clinics on voluntary basis. 51-Chromium EDTA (51Cr-EDTA) plasma level was used to measure the reference GFR. The serum creatinine was determined by IDMS reference modified Jaffe kinetic assay (CrJaffe). The predictive capabilities of MDRD and CKD-EPI based equations were calculated. Data was analysed using SPSS version 20 and correlation, bias, precision and accuracy were determined.Results: A total of 113 subjects with mean age of 58.12 ± 14.76 years and BMI of 25.99 ± 4.29 kg/m2 were recruited. The mean reference GFR was 66.98 ± 40.65 ml/min/1.73m2, while the estimated GFR based on MDRD and CKD-EPI formula were 62.17 ± 40.40, and 60.44 ± 34.59, respectively. Both MDRD and CKD-EPI were well-correlated with reference GFR (0.806 and 0.867 respectively) and statistically significant with p < 0.001. In the overall cohort, although MDRD had smaller bias than CKD-EPI (4.81 vs. 6.54), CKD-EPI was more precise (25.22 vs. 20.29) with higher accuracy within 30% of measured GFR (79.65 vs. 86.73%).Conclusion: The CKD-EPI equation appeared to be more precise and accurate than the MDRD equation in estimating GFR in our cohort of multi-ethnic populations in Malaysia. [ABSTRACT FROM AUTHOR]

Résumé Le débit de filtration glomérulaire est le meilleur marqueur quantitatif de fonction rénale. Il permet le diagnostic et la classification en cinq stades de gravité de la maladie rénale chronique. La mesure du débit de filtration glomérulaire repose en théorie sur le calcul de la clairance urinaire de substances exogènes telles l’inuline ou l’éthylène-diamine-tétra-acétique acide marqué au chrome 51. En pratique, le débit de filtration glomérulaire est le plus souvent estimé à partir d’équations dérivées de la créatinine plasmatique. Ce travail passe en revue l’ensemble des méthodes destinées à mesurer ou approcher le débit de filtration glomérulaire, et s’attache à décrire les évolutions récentes dans ce domaine, incluant celles concernant les méthodes de dosage de la créatinine plasmatique, les estimateurs dérivés de la concentration de créatinine et de la cystatine. La place de la mesure du débit de filtration glomérulaire par clairance de traceurs exogènes est également discutée. Glomerular filtration rate is the best quantitative marker of renal function. It allows diagnosis and classification of severe chronic kidney disease into five stages. Theoretically, the measurement of glomerular filtration rate is based on the calculation of urinary clearance of exogenous substances such as chromium 51-labeled inulin or ethylenediaminetetraacetic acid ([ 51 Cr]-EDTA). In practice, glomerular filtration rate is most often estimated from equations derived from plasma creatinine. This article reviews the range of methods used to measure or approximate glomerular filtration rate and attempts to describe recent developments in this area, including those related to plasma creatinine assay methods, creatinine and cystatin C concentration-derived estimations. Measurement of glomerular filtration rate by the clearance of exogenous tracers is also discussed. [ABSTRACT FROM AUTHOR]

Aims: The continuing growth of the population with end-stage renal disease (ESRD) in the past two decades has been recognized as a global health burden. In 2002, a definition of chronic kidney disease (CKD) was introduced and different categories of CKD have been reported in the general population. In this study, we examined the prevalence of CKD in primary health care in Germany. Subjects and methods: From 2004 to 2007 the prevalence of CKD was estimated in the Diabetes Cardiovascular Risk-Evaluation Targets and Essential Data for Commitment of Treatment (DETECT) study using the Simplified Modification of Diet in Renal Disease (MDRD) and the CKD Epidemiology Collaboration (CKD-EPI) equations. A sample of 4,080 subjects were analysed with detailed laboratory and comorbidity assessment from 851 primary care centres across Germany. Results: The prevalence of CKD (≤60 ml/min/1.73 m) was 27.9 % estimated by CKD-EPI equation (MDRD eGFR 36.1 %) and the prevalence of CKD increased with age and during follow-up. The overall decline in eGFR per year was −1.83 ml/min/year (CKD-EPI). Women have shown a higher decline in eGFR than men. The prevalence of CKD was highest in coronary artery disease patients, followed by diabetes mellitus and arterial hypertension. Individuals with diabetes mellitus have shown the highest progress developing CKD. Conclusion: In this representative sample of patients seeking medical advice in primary care, the prevalence of impaired kidney function was almost one third. Given the therapeutic implications, our results call for focused measures to increase the awareness of CKD in primary care. [ABSTRACT FROM AUTHOR]

Glomerular filtration rate (GFR) measurements are critical in patients with hepatic cirrhosis but potentially erroneous when based on serum creatinine. New equations for estimated GFR (eGFR) have shown variable performance in cirrhotics, possibly because of inaccuracies in reference methods for measured GFR (mGFR). The primary objective was to compare the performance of 4 improved eGFR equations with a 1-compartment, 2-sample plasma slope intercept 99mTc-DTPA mGFR method to determine whether any of the eGFR calculations could replace plasma 99mTc-DTPA mGFR in patients with cirrhosis. The secondary objective was to test the hypothesis that mGFR using voluntary voided urine collections introduces error compared with plasma-only methods. Methods: Fifty-four patients with hepatic cirrhosis underwent mGFR determinations from 2 plasma samples at 1 and 3 h after intravenous administration of 185 MBq of 99mTc-DTPA. GFR was also generated by a UV/P calculation derived from blood and urine samples. These mGFRs were compared with the eGFRs generated by 4 estimating equations: MDRD (Modified Diet in Renal Disease), CKD-EPI (Chronic Kidney Disease-Epidemiology Collaboration) (serum creatinine [SCr]), CKD-EPI (cystatin [CysC]), and CKD-EPI (CysC+SCr). eGFRs were compared with mGFRs by Pearson correlation, precision, bias, percentage bias, and accuracy (eGFRs varying by <10% [p10], <20% [p20] or <30% [p30] from the corresponding mGFR). Results: All eGFRs showed poorer performance when the UV/P 99mTc-DTPA mGFR was used as the reference than when the plasma 99mTc-DTPA mGFR was used. When compared with the plasma 99mTc-DTPA mGFR method, the performance of all eGFR equations was superior to most published reports. There was a moderately good positive correlation between eGFRs and mGFRs. When compared with plasma 99mTc-DTPA mGFR, precision of eGFRs was in the range of 14-20 mL/min and showed a negligible bias. Compared with the plasma 99mTc-DTPA mGFR, CKD-EPI (CysC+SCr) showed the best overall performance and accuracy, at 85.19% (p30), 75.93% (p20), and 42.59% (p10). Conclusion: Estimating equations for measuring eGFR performed better than in most published reports, attributable to use of the plasma 99mTc-DTPA mGFR method as a reference. CKD-EPI (CysC+SCr) eGFR showed the best overall performance. However, more discriminating methods may be required when accurate GFR measurements are necessary. mGFR measurements using urine collections may introduce error compared with plasma-only methods. [ABSTRACT FROM AUTHOR]

Background In this paper we evaluated the relationship between trough DAB concentration with eGFR calculated using CRE and CYS based formulas. Materials and methods We considered 100 patients. eGFR was calculated using CKD-EPIcreat, CG, MDRD, CKD-EPIcys and CKD-EPIcombined equations. DAB dosage was selected on the basis of CKD-EPIcreat and relationship between trough DAB concentration and eGFRs was evaluated. Results Trough DAB concentration roughly correlates with eGFR calculated using various formulas. CKD-EPIcreat eGFR was higher than CKD-EPIcys. In patients receiving a DAB dosage considered adequate using CKD-EPIcreat eGFR but considered excessive using CKD-EPIcys, we observed higher DAB trough concentration and an increased prevalence of subjects with drug concentration > 200 ng/mL. Conclusion These results suggest that eGFR alone was unable to fully explain trough DAB plasma concentration. Therefore a drug's prescription schedule based on eGFR only should be inadequate. We observed a better correlation between trough DAB concentration and CKD-EPIcys rather than CKD-EPIcreat eGFR. Thus, in patients chronically treated with DAB for thromboprophylaxis in nonvalvular atrial fibrillation evaluation of eGFR using a cystatin base formula should be considered. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD) is an important epidemic and public health problem that is associated with a significant risk for vascular disease and early cardiovascular mortality as well as progression of kidney disease. Currently it is classified into five stages based on the glomerular filtration rate (GFR) as recommended by many professional guidelines. Radiolabelled methods for measuring GFR are accurate but not practical and canbe used only on a very limited scale while the traditional methods require timed urine collection with its drawback of inaccuracy, cumbersomeness and inconvenience for the patients. However, the development of formula-based calculation of estimated GFR (eGFR) has offered avery practical and easy approach for converting serum creatinine value into GFR result taking into consideration patient’s age, sex, ethnicity and weight (depending on equation type). The commonly used equations include Cockraft and Gault (1976), Modification of Diet in Renal Disease (MDRD) (1999) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) (2009). It is the implementation of these equations particularly the MDRD that has raised the medical awareness in the diagnosis and managementof CKD and its adoption by many guidelines in North America and Europe. The impact and pitfalls of each of these equations in the screening, diagnosis and management of patients with CKD are presented and discussed in this review.

Background: HbA1c is correlated with the estimated glomerular filtration rate (eGFR) and diastolic blood pressure (DBP). Our main objective was to evaluate the trend of biochemical and clinical variables, in relation to the eGFR in patients with type 2 diabetes mellitus (T2DM). Methods: This was a retrospective, longitudinal, and descriptive study, including patients with T2DM, who were cared for from January 2014 until December 2014, at the Clínica de Diabetes, Hospital Regional "Gral. Ignacio Zaragoza", ISSSTE, Mexico City, Mexico. eGFR was calculated using three formulas: the chronic kidney disease -epidemiology collaboration (CKD-EPI), Cockcroft-Gault, and modification of diet in renal disease (MDRD), during two periods of observation, 3 and 6 months. The results were compared by Student t tests or Wilcoxon-Mann-Whitney test depending on the variable distribution. Pearson correlation was employed to determine the relation between the eGFR determined with each formula and the analyzed variables. Results: The mean age was 56.5±11.3 years in the group of 3 months'follow-up (n=110) and 57.1±13.8 years in the group of 6 months' follow-up (n=47). In both groups, the formula with the lowest percentages of cases of CKD was CKD-EPI and the difference of this formula had a basal and final significant positive correlation with the DBP. Conclusion: The CKD-EPI formula showed the lowest percentages of cases of CKD in a short follow-up period, and its difference is consistently associated with the DBP, confirming the importance of controlling the later to mitigate the evolution to CKD. [ABSTRACT FROM AUTHOR]

Objectives The recent guideline for the evaluation and management of Chronic Kidney Disease recommends assessing GFR employing equations based on serum creatinine; despite this, creatinine clearance 24-hour urine collection is used routinely in many settings. In this study we compared the classification assessed from CrCl (creatinine clearance 24 h urine collection) and e-GFR calculated with CKD-EPI or MDRD formulas. Design and methods In this retrospective study we analyze consecutive laboratory data: creatinine clearance 24 h urine collection, serum creatinine and demographic data such as sex and age from 15,777 patients > 18 years of age collected from 2011 to 2013 in our laboratory at Careggi Hospital. The results were then compared to the estimated GFR calculated with the equations according to the recent treatment guidelines. Consecutive and retrospective laboratory data (creatinine clearance 24 h urine collection, serum creatinine and, demographic data such as sex and age) from 15,777 patients > 18 years of age seen at Careggi Hospital were collected. Results Comparison between e-GFR calculated with CKD-EPI or MDRD formulas and GFR according CrCl determinations and bias [95% CI] were 11.34 [− 47,4/70.1] and 11.4 [− 50.2/73] respectively. The concordance for 18/65 years aged group when compared with e-GFR classification between MDRD vs CKDEPI, MDRD vs CrCl and CKD-EPI vs CrCl were 0.78, 0.34, and 0.41 respectively, while in the 65/110 years aged group the concordance Kappas were 0.84, 0.38, and 0.36 respectively. Conclusions The use of CrCl provides a different classification than the estimation of GFR using a prediction equation. The CrCl is unreliable when it is necessary to identify CKD subjects with decrease of GFR of 5 ml/min/1.73 m 2 /year. [ABSTRACT FROM AUTHOR]

Background: The frequencies of apolipoprotein L1 (APOL1) variants and their associations with chronic kidney disease (CKD) vary substantially in populations from Africa. Moreover, available studies have used very small sample sizes to provide reliable estimates of the frequencies of these variants in the general population. We determined the frequency of the two APOL1 risk alleles (G1 and G2) and investigated their association with renal traits in a relatively large sample of mixed-ancestry South Africans. APOL1 risk variants (G1: rs60910145 and rs73885319; G2: rs71785313) were genotyped in 859 African mixed ancestry individuals using allele-specific TaqMan technology. Glomerular filtration rate (eGFR) was estimated using the Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. Results: The frequencies of rs73885319, rs60910145 and rs71785313 risk alleles were respectively, 3.6 %, 3.4 %, and 5.8 %, resulting in a 1.01 % frequency of the APOL1 two-risk allele (G1:G1 or G1:G2 or G2:G2). The presence of the two-risk allele increased serum creatinine with a corresponding reduction in eGFR (either MDRD or CKD-EPI based). In dominant and log-additive genetic models, significant associations were found between rs71785313 and systolic blood pressure (both p ≤ 0.025), with a significant statistical interaction by diabetes status, p = 0.022, reflecting a negative non-significant effect in nondiabetics and a positive effect in diabetics. Conclusions: Although the APOL1 variants are not common in the mixed ancestry population of South Africa, the study does provide an indication that APOL1 variants may play a role in conferring an increased risk for renal and cardiovascular risk in this population. [ABSTRACT FROM AUTHOR]

Background: The most superior GFR-estimating equation from the viewpoint of cardiovascular disease (CVD) prediction remains unclear. Thus, we performed cross-sectional comparison between two GFR-estimating equations (Japanese GFR equation and coefficient-modified CKD-EPI equation) and CVD incidence using Japanese nationwide 'specific health checkup' data. Methods: We recruited Japanese residents (241,159 individuals; mean 63 years; male, 38.6 %) who had not experienced CVD event (cardiac disease or stroke, or both). We calculated estimated GFR using two equations, and compared their predictive value for first symptomatic CVD event within 1 year. Results: Of all subjects, the mean GFR estimated by the Japanese GFR equation (JPN-eGFR) modified for Japanese was 75.83 ± 16.18 mL/min/1.73 m, and that by the coefficient-modified CKD-EPI equation (mCKDEPI-eGFR) was 76.39 ± 9.61 mL/min/1.73 m. Area under the receiver operating characteristics curves (95 % confidence intervals) for predicting CVD event by mCKDEPI-eGFR vs. JPN-eGFR were 0.596 (0.589-0.603) vs. 0.562 (0.554-0.569). Using mCKDEPI-eGFR, the crude odds ratio (OR) for CVD incident in the 4th quartile group was far more than double (OR 2.46, 95 % CI 2.29-2.66) that in the 1st quartile group. Using JPN-eGFR, the crude OR in the 4th quartile group was less than double (OR 1.61, 95 % CI 1.51-1.73) that in the 1st quartile group. However, such superior predictive value of mCKDEPI-eGFR disappeared after adjustment for confounding factors (age, gender, BMI, presence of proteinuria, hypertension, diabetes, dyslipidemia and current smoking). Conclusion: GFR estimated by the coefficient-modified CKD-EPI equation was more closely related to CVD incidence than that estimated by the Japanese GFR equation. However, it is possible that low mCKDEPI-eGFR also reflects some cardiovascular risk(s) other than kidney dysfunction. [ABSTRACT FROM AUTHOR]

Background/Aims: Accurate staging of chronic kidney disease (CKD) is very important. We tried to identify difference in GFR evaluation between CKD-EPI and Gates method with renal scintigraphy and which variables are associated with these differences. Methods: We retrospectively reviewed the records of 341 patients who underwent dynamic renal scintigraphy in the last 5 years. Patients were categorized according to KDIGO staging I to V, using the eGFR calculated with the CKD-EPI equation. Secondarily, we stratified patients according to treatment with renin-angiotensin system (RAS) inhibitors. Results: Gates method tends to underestimate GFR especially in CKD stage I (mean -22.2 ml/min) and II (mean -12.5 ml/min). The division in quartiles of ages showed an underestimation of GFR only in the first quartile of age (< 50 years old). Gates method underestimation of GFR was more pronounced in stage I patients treated with RAS inhibitors (mean -34.6 ml/min). The same occurs in stage II, even though to a lesser extent. Conclusion: The assessment of GFR by the Gates method must be carefully considered in the early stages of CKD, especially in younger patients. Moreover, the difference is more pronounced in patients treated with RAS inhibitors. Longitudinal studies will prove which method better predicts cardiovascular or renal events. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Copyright of Nefrologia is the property of Revista Nefrologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nefrologia is the property of Revista Nefrologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The National Kidney Disease Education Program group demonstrated that MDRD equation is sensitive to creatinine measurement error, particularly at higher glomerular filtration rates. Thus, MDRD-based eGFR above 60mL/min/1.73m2 should not be reported numerically. However, little is known about the impact of analytical error on CKD-EPI-based estimates. This study aimed at assessing the impact of analytical characteristics (bias and imprecision) of 12 enzymatic and 4 compensated Jaffe previously characterized creatinine assays on MDRD and CKD-EPI eGFR. In a simulation study, the impact of analytical error was assessed on a hospital population of 24084 patients. Ability using each assay to correctly classify patients according to chronic kidney disease (CKD) stages was evaluated. For eGFR between 60 and 90mL/min/1.73m2, both equations were sensitive to analytical error. Compensated Jaffe assays displayed high bias in this range and led to poorer sensitivity/specificity for classification according to CKD stages than enzymatic assays. As compared to MDRD equation, CKD-EPI equation decreases impact of analytical error in creatinine measurement above 90mL/min/1.73m2. Compensated Jaffe creatinine assays lead to important errors in eGFR and should be avoided. Accurate enzymatic assays allow estimation of eGFR until 90mL/min/1.73m2 with MDRD and 120mL/min/1.73m2 with CKD-EPI equation. [Copyright &y& Elsevier]

Background The question for prevalence estimation and validation of the various eGFRs in old age is still under debate. To assess renal function with increasing age, we estimated mean eGFR, in subjects aged 20-85 years. Furthermore, we assessed prevalence of eGFR in a populationbased sample of 85 year olds and investigated the performance of these eGFRs in predicting mortality in the oldest old. Methods Renal function with increasing age was assessed in subjects aged 20-85 years from the Bronovo Study Cohort. We estimated prevalences of eGFRs and mortality risks in a population-based study of persons aged 85 years and older, the Leiden 85-plus Study. The GFRs were estimated by three different formulas. Results After the age of 70 years, the C-G tended to give relatively lower eGFRs. An eGFR < 60 was found in 90% of the subjects aged 85 years as calculated by C-G, in 55% of the subjects using MDRD and in 68% of the 85 year old subjects as calculated by CKD-EPI. When renal function was <30 ml/min/1.73m2, an increased mortality risk was observed by C-G (HR 1.9 (95% CI 1.1-3.3)), by MDRD (HR 3.5 (95% CI 1.8-6.7)), whereas by CKD-EPI significance was not reached (HR 2.4 (95% CI 0.9-6.4)). Conclusions Our study demonstrates that in subjects above age 70, C-G gives lower estimates of renal function when compared to MDRD and CKD-EPI. Furthermore, prevalence of renal dysfunction (CKD stage 1-3) at age 85 years was highest for C-G (90%), lowest for MDRD (55%), and 68% for CKD-EPI. Moreover, we found that in subjects aged 85 years MDRD predicted mortality best. [ABSTRACT FROM AUTHOR]

Background Renal function is often estimated using one of several glomerular filtration rate (GFR) estimating equations. However, there is no consensus which estimating equation performs best in patients with advanced renal failure. Methods We compared the performance of five different estimated GFR (eGFR) equations [Cockcroft-Gault, Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease (CKD) Epidemiology collaboration (CKD-EPI) and Mayo Clinic and Lund-Malmö] with measured GFR (plasma iohexol clearance) in 2098 referred CKD patients with mGFR <30 mL/min/1.73 m2. Results There were 398 patients with an mGFR ≤10 mL/min/1.73 m2, 1974 with a measured GFR (mGFR) 11–20 mL/min/1.73 m2 and 749 patients with mGFR 21–30 mL/min/1.73 m2. Across the entire range, the median bias of eGFR was lowest for the Lund-Malmö equation (0.7 mL/min/1.73 m2), followed by the CKD-EPI (1.2 mL/min/1.73 m2), the MDRD (1.6 mL/min/1.73 m2), Mayo Clinic equation (1.7 mL/min/1.73 m2) and Cockcroft-Gault equation (4.6 mL/min/1.73 m2). The best accuracy within 30% of mGFR was also for Lund-Malmö (76%), while it was similar for CKD-EPI, MDRD and Mayo (65–67%). The Cockcroft-Gault had the worst accuracy of only ∼54%.The median bias was stable across mGFR categories, while the accuracy within 30% of mGFR became worse with decreasing mGFR. All equations performed best among patients with hereditary kidney diseases and tubulointerstitial disease. Accuracy was generally worse for patients >65 years of age and for those with diabetic nephropathy. Conclusions In patients with advanced renal failure, the GFR-estimating equations show reasonably good performance on the population level. On the individual patient level, they are inaccurate, especially in elderly patients and those with diabetic nephropathy. [ABSTRACT FROM PUBLISHER]

Objectives: The aim of this paper was to compare the agreement between creatinine measured by Jaffe and enzymatic methods and their putative influence on eGFR as calculated by the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation in healthy and diabetic individuals. Design and methods: Cross-sectional study conducted in 123 adult southern Brazilians with GFR>60mL/min/1.73m2 (53 patients with type 2 diabetes, 70 healthy volunteers). Mean age was 49±16years (range of 19–86). Most were female (55%) and white (83%). Creatinine was measured by a traceable Jaffe method (Modular P, Roche Diagnostic) and by an enzymatic method (CREA plus, Roche/Hitachi 917). GFR was measured by the 51Cr-EDTA single-injection method. Results: Serum creatinine measured by the Jaffe and enzymatic methods was similar in healthy subjects (0.79±0.16 vs. 0.79±0.15mg/dL, respectively, P=0.76), and diabetic patients (0.96±0.22 vs. 0.92±0.29mg/dL, respectively, P=0.17). However, the correlation between the two methods was higher in the healthy group (r=0.90 vs. 0.76, P<0.001). The difference between Jaffe creatinine and enzymatic creatinine was <10% in 63% of cases in the healthy group and 40% of cases in the diabetes group (P=0.018). In the subset of patients with diabetes, eGFR based on enzymatic assay results showed better agreement with measured GFR than did eGFR based on Jaffe results. Conclusion: Jaffe and enzymatic creatinine methods show adequate agreement in healthy subjects, but in the presence of diabetes, the enzymatic method performed slightly better. [ABSTRACT FROM AUTHOR]