MDRD Equation Research Articles

Adoption of CKD-EPI (2021) for GFR estimation - implications for UK practice.

Recommendations to move to a race free estimating equation for glomerular filtration rate have gained increasing prominence since 2021. We wished to determine the impact of any future adoption upon the CKD patient population of a large teaching hospital, with a population breakdown largely similar to that of England as a whole. We compared four estimating equations (MDRD, CKD-EPI (2009), CKD-EPI (2021) and EKFC) using the Bland-Altman method. Bias and precision were calculated (in both figures and percentages) for all patients with CKD and specific subgroups determined by age, ethnic group, CKD stage and sex. CKD stage was assessed using all four equations. All equations studied had a positive bias in South Asian patients and a negative bias in Black patients compared to CKD-EPI (2021). Similarly, there was a positive bias in White patients across all equations studied. Comparing CKD-EPI (2009) and EKFC this positive bias increased as patients aged, the opposite was seen with MDRD. Between 10% and 28% of patients in our dataset changed their CKD staging depending upon estimating equation used. Our work confirms previous findings that the MDRD equation overestimates eGFR in South Asians and underestimates eGFR in Blacks. The alternative equations also demonstrated similar bias. This may, in part, explain the health inequalities seen in ethnic minority patients in the UK. Applying our findings to the UK CKD population as a whole would result in anywhere from 260,000 - 730,000 patients having their CKD stage reclassified, which in turn will impact secondary care services.

Estimates of eskd risk and timely kidney replacement therapy education

BackgroundKidney replacement therapy (KRT) needs preparation and its timing is difficult to predict. Nephrologists’ predictions of kidney failure risk tend to be more pessimistic than the Kidney Failure Risk Equation (KFRE) predictions. We aimed to explore how physicians’ risk estimate related to referral to KRT education, vs. the objective calculated KFRE.MethodsProspective observational study of data collected in chronic kidney disease (CKD) clinics of the Veterans Affairs Medical Center San Diego and the University of California, San Diego. The study included 257 participants who were aged 18 years or older, English speaking, prevalent CKD clinic patients, with estimated glomerular filtration rate (eGFR) < 60 mL/min per 1.73 m2 (MDRD equation). The exposure consisted of end stage kidney disease (ESKD) risk predictions. Nephrologists’ kidney failure risk estimations were assessed: “On a scale of 0–100%, without using any estimating equations, give your best estimate of the risk that this patient will need dialysis or a kidney transplant in 2 years.” KFRE was calculated using age, sex, eGFR, serum bicarbonate, albumin, calcium, phosphorus, urine albumin/creatinine ratio. The outcomes were the pattern of referral to KRT education (within 90 days of initial visit) and kidney failure evaluated by chart review. The population was divided into groups either by nephrologists’ predictions or by KFRE. Referral to KRT education was examined by group and sensitivity and specificity were calculated based on whether participants reached kidney failure at 2 years.ResultsA fifth were referred for education by 90 days of enrollment. Low risk patients by both estimates had low referral rates. In those with nephrologists’ predictions ≥ 15% (n = 137), sensitivity was 71% and specificity 76%. In those with KFRE ≥ 15% (n = 55), sensitivity was 85% and specificity 41%.ConclusionsAlthough nephrologists tend to overestimate patients’ kidney failure risk, they do not appear to act on this overestimation, as the rates of KRT education referrals are lower than expected when a nephrologist identifies a patient as high risk.Clinical Trial NumberNot applicable

Association of Inflammatory Marker C-Reactive Protein and Interleukin-6 with Stages 3-5 of Chronic Kidney Disease

Background: Despite different strategy to retard the progression of CKD, majority still progress to ESRD. Other than conventional risk factors inflammation is considered as one of the reversible factors responsible for CKD progression which can be intervened. Therefore, we have studied the level of inflammatory marker CRP and IL-6 at stages 3-5 of CKD patients and their association with CKD stage progression determined by eGFR. Methods: We have conducted a cross sectional study among 150 CKD patients and 32 healthy controls at OPD of Nephrology department of National Institute of Kidney Diseases and Urology, Dhaka from January`2016 to December`2016. Purposive sampling method was the tool for case selection and CKD was defined as eGFR &lt;60ml/min/1.73m2. AKI, history of dialysis, kidney transplant, patients having acute infection, malignancy or liver disease, received chemotherapy or immunotherapy (&lt;6 months) and patients with connective tissue disease were the exclusion criteria. Fasting blood glucose, Hb%, serum Ca++, serum PO4, serum total cholesterol and serum triglyceride level were measured for both case and controls. eGFR has been calculated using MDRD equation. For the cases CRP had been measured on two occasions at an interval of one and half month. Those cases who had raised CRP level in both occasions were selected for measurement of IL-6 from second sample. CRP had been measured by turbidimetry method using fully automated chemistry analyzer. IL-6 had been measured using enzyme linked immunosorbent assay (ELISA) based on the Biotin double antibody sandwich technology. Scatter diagram and multiple regression models were used to examine the association between CRP and IL-6 with stage 3-5 of CKD denoted by eGFR. Results: The mean of CRP were 9.5±2.7 mg/L in CKD patients vs. 2.9±0.5 mg/L in controls without CKD and the mean of IL-6 were 29.5±13.0 pg/ml in CKD patients vs. 3.3±0.3 pg/ml in controls without CKD. Both were elevated and significant statistically (p=.001). Scatter diagram showing correlation coefficient (r value) -0.592 and -0.615 for eGFR vs. CRP and eGFR vs. IL-6 respectively which indicate both are negatively correlated with eGFR. But IL-6 had a more strong negative correlation. Multiple regression analysis shows regression co efficient (B) for CRP and IL-6 is -1.251 and -2.826 respectively after taking into account other factors which can alter eGFR level (age, Hb%, serum Calcium, S. Total Cholesterol, S.PO4, S. Triglyceride) that indicates in the prediction of eGFR, IL-6 had significant negative association than CRP after adjusting the conventional factors responsible for CKD progression. Conclusion: Our data suggest that though CRP and IL-6 both are significantly raised in advanced CKD stage 3-5, IL-6 is more rapidly increasing and more strongly associated than CRP with the severity of CKD measured by eGFR.

Assessment of impaired glomerular filtration rate and associated factors in South West Ethiopia: a cross-sectional study

IntroductionCurrently, kidney disease is an increasing major health problem worldwide. It is expected to be the 5th ranked cause of death by 2040. If it is early detected, further complication caused by kidney disease will be minimized. An assessment of impaired glomerular filtration rate (eGFR) has potential aids in early identification and treatment of kidney disease. However, in hospital practice instead of using eGFR, direct measurement of serum creatinine level is used for assessing renal function. Hence, this study is aimed to assess the magnitude and associated factors of impaired glomerular filtration rate among admitted patients in Wolkite University Specialized Teaching Hospital (WKUSTH).ObjectiveTo assess the magnitude and associated factors of impaired glomerular filtration rate in WKUSTH, Ethiopia 2023.MethodInstitutional based cross-sectional study with secondary data was conducted. 338 participants were selected by a convenient sampling technique. Epidata 3.1 version for data entry and SPSS version 20 for data analysis was used. Bivariate analysis was used to screen candidate variables for multivariate analysis. In the multivariate analysis a P-value < 0.05 were considered statistically significant.ResultsThe study enrolled 338 patients admitted to WUSTH. Seventy (20.7%) (95% CI: 16.6–25.4%) of them had impaired eGFR according to Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation and Modification of Diet in Renal Disease (MDRD-4). older age (AOR 3.38, 95% CI; 1.31, 8.71), hypertension (AOR 17.8, 95% CI; 7.75, 41.22), anemia (AOR 2.51, 95% CI; 1.11, 5.83) DM (AOR 11.2, 95% CI; 4.11, 30.73), and high BMI (AOR 7.56, 95% CI; 3.16, 18.08), were independently associated with impaired eGFR.ConclusionsThe magnitude of impaired eGFR was prevalent among adult patients admitted to WKUSTH medical ward with different medical conditions. Old age, Hypertension, Diabetes, high body mass index, and Anemia were significantly associated with impaired eGFR both in CKD-EPI and MDRD-4 equation. Estimation of GFR for all hospitalized adults with known CKD risk factors might help in early detection of CKD and prevent complications.

Cisplatin eligibility in the neoadjuvant setting of patients with muscle-invasive bladder cancer undergoing radical cystectomy.

To examine the agreement of different calculated estimated glomerular filtration rate (eGFR) formulas and measured creatinine clearance (CrCI) at the primary diagnosis of muscle-invasive bladder cancer (MIBC). We performed a multicenter analysis of patients with MIBC, treated with cisplatin-based neoadjuvant chemotherapy (NAC) and radical cystectomy (RC), or with RC alone, between 2011 and 2021. Baseline eGFR was computed using 4 calculated serum equations including Cockcroft-Gault (CG), MDRD, CKD-EPI 2009, and race-free CKD-EPI 2021. To examine the association between calculated eGFR and measured CrCI, subgroup analyses were performed among patients in whom measured 24-hour urine CrCl was determined. Cisplatin-ineligibility was defined as CrCI and/or eGFR < 60mL/minute per 1.73 m2. Of 956 patients, 30.0%, 33.3%, 31.9%, and 27.7% were found to be cisplatin-ineligible by the CG, MDRD, CKD-EPI, and race-free CKD-EPI equations (P = .052). The concordance between calculated eGFR formulas was rated substantial (Cohen's kappa (k): 0.66-0.95). Among the subgroup (n = 245) with measured CrCl, 37 (15.1%) patients had a CrCI less than 60mL/minute. Concordance between measured CrCl and calculated eGFR was poor (ĸ: 0.29-0.40). All calculated eGFR formulas markedly underestimated the measured CrCI. Specifically, 78%-87.5% of patients with a calculated eGFR between 40 and 59mL/minute exhibited a measured CrCI ≥ 60mL/minute. Comparing calculated eGFR formulas, similar percentages of patients with MIBC were deemed cisplatin-ineligible. However, a significant number of patients could be upgraded by being cisplatin-fit based on measured CrCI, particularly when the calculated eGFR was falling within the gray range of 40-59mL/minute.

The Relationship of Certain Physiological Parameters and VEGF with chronic kidney disease

Chronic kidney disease (CKD) is a major health burden affecting over 10% of the global population. As kidney function deteriorates across progressive CKD stages, systemic inflammation and cytokine activity are upregulated which further drive disease advancement. Vascular endothelial growth factor (VEGF) also becomes increasingly dysregulated with implications for vascular pathology. However, step-wise changes in these pathways correlating with declining renal filtration have not been clearly elucidated : Objective: This study aimed to evaluate the utility of estimated glomerular filtration rate (eGFR) using the MDRD equation for disease staging, and to explore potential non-invasive biomarkers, including inflammatory markers and vascular endothelial growth factor (VEGF) expression, for early prediction of renal dysfunction; Methods: 50 CKD patients categorized into stages 1-4 (n=10 each) and 10 healthy controls were recruited. Serum creatinine was measured enzymatically and eGFR calculated. Plasma TNF-alpha and CRP concentrations were determined by ELISA. Relative VEGF mRNA levels were quantified by RT-qPCR and normalized to GAPDH; Results: Advancing CKD stage showed step-wise increases in serum creatinine (p&lt;0.001) and reductions in mean eGFR (p&lt;0.001). TNF-alpha and CRP also demonstrated significant stage-dependent elevations beginning from early stage 2 disease relative to controls (p&lt;0.01). VEGF expression escalated progressively from ~3 fold in stage 2 to ~129 fold in stage 4 CKD compared to normal individuals (p&lt;0.001); Conclusions: Deteriorating renal function is associated with substantive aggravations in systemic inflammation and VEGF expression. Tracking these biomarkers could enable early detection of underlying pathology prior to onset of severe kidney impairment.

The Relationship of Certain Physiological Parameters and VEGF with chronic kidney disease

Chronic kidney disease (CKD) is a major health burden affecting over 10% of the global population. As kidney function deteriorates across progressive CKD stages, systemic inflammation and cytokine activity are upregulated which further drive disease advancement. Vascular endothelial growth factor (VEGF) also becomes increasingly dysregulated with implications for vascular pathology. However, step-wise changes in these pathways correlating with declining renal filtration have not been clearly elucidated : Objective: This study aimed to evaluate the utility of estimated glomerular filtration rate (eGFR) using the MDRD equation for disease staging, and to explore potential non-invasive biomarkers, including inflammatory markers and vascular endothelial growth factor (VEGF) expression, for early prediction of renal dysfunction; Methods: 50 CKD patients categorized into stages 1-4 (n=10 each) and 10 healthy controls were recruited. Serum creatinine was measured enzymatically and eGFR calculated. Plasma TNF-alpha and CRP concentrations were determined by ELISA. Relative VEGF mRNA levels were quantified by RT-qPCR and normalized to GAPDH; Results: Advancing CKD stage showed step-wise increases in serum creatinine (p&lt;0.001) and reductions in mean eGFR (p&lt;0.001). TNF-alpha and CRP also demonstrated significant stage-dependent elevations beginning from early stage 2 disease relative to controls (p&lt;0.01). VEGF expression escalated progressively from ~3 fold in stage 2 to ~129 fold in stage 4 CKD compared to normal individuals (p&lt;0.001); Conclusions: Deteriorating renal function is associated with substantive aggravations in systemic inflammation and VEGF expression. Tracking these biomarkers could enable early detection of underlying pathology prior to onset of severe kidney impairment.

A Comparison of Renal Effects between Empagliflozin and Linagliptin in Diabetic Patients with Chronic Kidney Disease: A Randomized Clinical Trial

Objective: The current study aimed to compare the renal effects of Empagliflozin with Linagliptin combined with Metformin in patients with type 2 diabetes mellitus (T2DM) and chronic kidney disease. combined with Metformin in patients with type 2 diabetes mellitus (T2DM) and chronic kidney disease. Materials and Methods: We conducted a randomized clinical trial on diabetic patients aged over 18 years with chronic renal failure and an EGFR between 20 to 60 ml/minutes/1.73 m2 corrected with the MDRD equation. Between January and December 2023, a total of 150 cases in Imam Hossein Hospital were randomized into two study arms of 75 cases receiving Empagliflozin (10 mg/day) and metformin or Linagliptin (5mg/day) and metformin for 6 months. The primary outcome was a change in chronic kidney disease (CKD) stage, while serum creatinine, fasting blood sugar (FBS), proteinuria, and blood pressure were evaluated at baseline, 3 and 6 months later. Results: The mean age of participants was 62.20 (± 4.45) years and 50% of them were females. Study indices including serum creatinine (P: 0.001), estimated glomerular filtration rate (eGFR) (P: 0.001), FBS (P: 0.001), HgA1c (P: 0.001), proteinuria (P: 0.001), and blood pressure (P: 0.001) reduced significantly over time in both groups. After adjustment for potential confounders, Empagliflozin reduced the level of serum creatinine independent of other factors. Conclusion: Empagliflozin significantly reduces the level of serum creatinine compared to Linagliptin in patients with T2DM and chronic renal failure.

Comparative Analysis of Seven Equations for Estimated Glomerular Filtration Rate and Their Impact on Chronic Kidney Disease Categorization in Korean Patients at Local Clinics and Hospitals.

(1) Background: Accurate estimation of the glomerular filtration rate (eGFR) is essential for the early detection of chronic kidney disease (CKD), targeted interventions, and ongoing monitoring. Although various equations for calculating eGFR exist, comparative studies on eGFR levels and the impact of these equations on CKD prevalence are limited in the Korean population. (2) Methods: We compared eGFR levels calculated using seven equations and investigated the prevalence of CKD through a retrospective analysis of the data from Korean adult patients who visited local clinics and hospitals and underwent simultaneous serum creatinine (Cr) and cystatin C (Cys-C) measurements. The equations analyzed were: 2006 MDRD, 2009 CKD-EPI Cr, 2012 CKD-EPI Cys-C, 2012 CKD-EPI Cr & Cys-C, 2021 CKD-EPI Cr, 2021 CKD-EPI Cr & Cys-C, and 2021 EKFC. (3) Results: This study included 6688 Korean patients (3736 men and 2952 women; median age: 61.4; IQR: 47.2-73.4). Among the equations, the median eGFR levels were the highest when using the 2021 CKD-EPI Cr & Cys-C equation (85.1 mL/min/1.73 m2) and the lowest when using the 2006 MDRD equation (73.4 mL/min/1.73 m2). The highest prevalence of decreased eGFR < 60 mL/min/1.73 m2 (equivalent to or worse than G3a CKD) was noted with the 2012 CKD-EPI Cys-C equation (32.4%), while the lowest was with the 2021 CKD-EPI Cr equation (22.9%), resulting in a maximum prevalence difference of 9.5%. (4) Conclusions: The prevalence of CKD varies based on the eGFR equation used and the patient's age. Equations that include Cys-C may identify a larger number of patients with decreased kidney function.

Comparison of the applicability of seven calculation equations of glomerular filtration rate among elderly people in China

BackgroundAt present, estimated glomerular filtration rate (eGFR) remains the most frequently utilized parameter in the evaluation of kidney injury severity. Numerous equations have been formulated based on serum creatinine (Scr) or serum cystatin C (Cysc) levels. However, there is a lack of consensus regarding the efficacy of these equations in assessing eGFR, particularly for elderly individuals in China. This study aimed to evaluate the applicability of the MDRD, MDRDc, CKD-EPI series, BIS1, and FAS equations within the Chinese elderly population.MethodsA cohort of 298 elderly patients with measured GFR (mGFR) was enrolled. The patients were categorized into three subgroups based on their mGFR levels. The eGFR performance was examined, taking into account bias, interquartile range (IQR), accuracy P30, and root-mean-square error (RMSE). Bland–Altman plots were employed to verify the validity of eGFR.ResultsThe participants had a median age of 71 years, with 167 (56.0%) being male. Overall, no significant differences in bias were observed among the seven equations (P > 0.05). In terms of IQR, P30, and RMSE, the BIS1 equation demonstrated superior accuracy (14.61, 72.1%, and 13.53, respectively). When mGFR < 30 ml/min/1.73 m2, all equations underestimated the true GFR, with the highest accuracy reaching only 59%. Bland–Altman plots indicated that the BIS1 equation exhibited the highest accuracy, featuring a 95% confidence interval (CI) width of 52.37.ConclusionsThis study suggested that the BIS1 equation stands out as the most applicable for estimating GFR in Chinese elderly patients with normal renal function or only moderate decline. 2020NL-085-03, 2020.08.10, retrospectively registered.

Advanced Oxidative Protein Products Had a Diagnostic Accuracy for Identifying Chronic Kidney Disease in Adult Population.

Chronic Kidney Disease (CKD) is a serious public health problem. Hyperglycemia stimulates the production of reactive oxygen species that cause oxidative damage to proteins. AOPPs constitute a group of oxidized dityrosine-containing proteins that are generated during periods of oxidative stress. They have proved to be a valuable early marker of oxidative tissue damage and active mediators of inflammation associated with the uremic state. To analyze if advanced oxidative protein products (AOPPs) have diagnostic accuracy for identifying chronic kidney disease (CKD) in the adult population. We conducted a diagnostic test validation study in 302 adults ≥20 years old, of both sexes, with and without T2D. After obtaining informed consent, a comprehensive clinical history, anthropometric measurements (weight, BMI) and blood pressure were recorded. Glucose, cholesterol, triglyceride, HDL-c, LDL-c and AOPPs were determinates. Glomerular filtration rate (GFR) was calculated using Cockcroft-Gault (C-G) corrected by body surface area (BSA, mL/min/1.73 m2), CKD-EPI and MDRD equations to identify five stages of CKD. This study follows the Standards for Reporting Diagnostic Accuracy Studies (STARD). The median value of AOPPs was 198.32 µmol/L (minimum-maximum value: 113.48-522.42 µmol/L). The group with patients diagnosed with T2D exhibited higher concentrations (median: 487.39 µmol/L) compared to the non-diabetic group (median: 158.50 µmol/L, p = 0.0001). The selected cut-off point was ≥200 µmol/L using the closest to the median value of AOPPs with sensitivity and specificity as follows: C-G: sensitivity 96.58%; specificity 80%; likelihood ratio: 4.83; CKD-EPI: sensitivity 95.76%; specificity 79.89%; likelihood ratio: 4.76; MDRD: sensitivity 86.55%; specificity: 73.22%; likelihood ratio: 3.23. A difference was observed between AOPPs and chronic kidney disease stage. This study provides evidence that AOPPs ≥ 200 µmol/L have diagnostic accuracy in identifying stage 4-5 CKD by C-G, MDRD and CKD-EPI equations in adults with and without T2D.

Validação das equações para estimativa da filtração glomerular ajustáveis por raça/cor em adultos de Vitória, Espírito Santo, Brasil

Abstract The assessment of renal function is performed using the glomerular filtration rate (GFR) whose measurement by creatinine clearance (ClCr) and is dependent on a 24-hour urine sample, hindering it use in primary healthcare. The equations that estimate GFR from serum creatinine make the test more accessible, however, their adjustments by race/color have been questioned in mixed populations. To test the agreement between CrCl and GFR estimated by formulas (Modification of Diet in Renal Disease [MDRD-4] and Chronic Kidney Disease Epidemiology Collaboration [CKD-EPI]), with or without adjusting for race/color, data were used from a sub-study of the National Health Survey (NHS) including 272 adults from Vitória/Espírito Santo who underwent a 24-hour urinary sampling. Analysis of variance (ANOVA) and the Bland-Altman method were adopted. There was adequate agreement between ClCr and equations, but the adjustment by race/color decreases the accuracy of both equations. In the race/color factor, there was similarity between groups for CrCl (p=0.21), suggesting that there is no difference in creatinine metabolism induced by skin color. It is concluded that MDRD and CKD-EPI equations perform satisfactorily in the evaluation of renal function, and the use of corrections for race/color is not recommended.

Validation of glomerular filtration estimation equations adjustable by race/colour in adults from Vitória, Espírito Santo, Brazil.

The assessment of renal function is performed using the glomerular filtration rate (GFR) whose measurement by creatinine clearance (ClCr) and is dependent on a 24-hour urine sample, hindering it use in primary healthcare. The equations that estimate GFR from serum creatinine make the test more accessible, however, their adjustments by race/color have been questioned in mixed populations. To test the agreement between CrCl and GFR estimated by formulas (Modification of Diet in Renal Disease [MDRD-4] and Chronic Kidney Disease Epidemiology Collaboration [CKD-EPI]), with or without adjusting for race/color, data were used from a sub-study of the National Health Survey (NHS) including 272 adults from Vitória/Espírito Santo who underwent a 24-hour urinary sampling. Analysis of variance (ANOVA) and the Bland-Altman method were adopted. There was adequate agreement between ClCr and equations, but the adjustment by race/color decreases the accuracy of both equations. In the race/color factor, there was similarity between groups for CrCl (p=0.21), suggesting that there is no difference in creatinine metabolism induced by skin color. It is concluded that MDRD and CKD-EPI equations perform satisfactorily in the evaluation of renal function, and the use of corrections for race/color is not recommended.

Correlation Between the C-G and MDRD Equations in Comparison to the CKD-EPI Equations in Geriatric Patients

Correlation Between the C-G and MDRD Equations in Comparison to the CKD-EPI Equations in Geriatric Patients

Comparison of GFR measurement with a two-blood sample technique using [99mTc]Tc-DTPA vs. creatinine-based equations in potential kidney donors.

Accurate determination of glomerular filtration rate (GFR) is crucial for selection of kidney donors. Nuclear medicine methods are considered accurate in measuring GFR but are not always easily available. The four-variable Modification of Diet in Renal Disease (MDRD4), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), and Full Age Spectrum (FAS) formulas are common equations for estimating GFR and are recommended for initial assessment of kidney donors. The aim of this study was to evaluate the performance of these GFR estimation equations compared with technetium-99m diethylenetriaminepentaacetic acid ([99mTc]Tc-DTPA) clearance. We compared GFR estimation by [99mTc]Tc-DTPA clearance using a two-blood sample method with estimation by MDRD4, CKD-EPI, and FAS creatinine-based equations in a population of healthy potential kidney donors. A total of 195 potential kidney donors (68.2% female; mean age 49 years, range 21-75 years) were included in this study. Mean [99mTc]Tc-DTPA measured GFR (mGFR) was 101.5 ± 19.1 mL/min/1.73 m2. All three equations underestimated the GFR value measured by [99mTc]Tc-DTPA (MDRD4: -11.5 ± 18.8 mL/min/1.73 m2; CKD-EPI: -5.0 ± 17.4 mL/min/1.73 m2; FAS: -8.3 ± 17.4 mL/min/1.73 m2). Accuracy within 30% and 10% of the measured GFR value was highest for CKD-EPI. The CKD-EPI equation showed better performance in estimating GFR in healthy potential kidney donors, proving to be a more accurate tool in the initial assessment of kidney donors. However, creatinine-based equations tended to underestimate kidney function. Therefore, GFR should be confirmed by another method in potential kidney donors.

Addition of bioimpedance-derived body cell mass improves performance of serum creatinine-based GFR estimation in a chronic kidney disease cohort.

Serum creatinine-based glomerular filtration rate (GFR) estimating equations are imprecise and systemic overestimate GFR in chronic kidney disease (CKD) populations with low muscle mass. Bioimpedance devices can measure body cell mass (BCM), a surrogate for muscle mass which has been included in a published GFR estimating equation. This BCM GFR equation is validated and compared with MDRD and CKD-EPI 2021 equations in an Indian CKD population. Patients with stable CKD stages 1-5 and voluntary kidney donors underwent measurement of serum creatinine, DTPA GFR and bioimpedance on the same day. BCM GFR was tested for consistency, agreement and performance with respect to DTPA GFR. A total of 125 study participants were enrolled, including 106 patients with CKD (Stage 1: 8; stage 2: 32, stage 3: 42, stage 4: 20 and stage 5: 4 patients) and 19 voluntary kidney donors, with 66% males, and a mean age of 43.3 (± 16.5) years. The median bias of BCM GFR was 5.45ml/min/1.73 m2 [95% confidence interval (CI) 4.2-8.3], absolute precision was 10.16ml/min/1.73 m2 [95% CI 4.5-12.6], P30 was 59.1% [95% CI 50.0-67.7] and accuracy was 8.62% [95% CI 6.4-20.0]. Kappa measurement of agreement was the highest for BCM GFR-based staging (0.628 vs 0.545 for MDRD and 0.487 for CKD-EPI). BCM-based GFR estimating equation performed better than MDRD and CKD-EPI equations in this Indian CKD population, and BCM GFR-based KDIGO staging was associated with lesser misclassification than the MDRD and CKD-EPI equations. Clinical Trials Registry of India (CTRI/2019/11/021850).

Estimated glomerular filtration rate calculated by serum creatinine lacks precision and accuracy in adults with type 2 diabetes with preserved renal function

AimsWe evaluated the performance of creatinine-based equations that are currently used to estimate glomerular filtration rate (GFR) in people with type 2 diabetes compared to measured GFR using gold-standard methods. MethodsIn this post-hoc analysis, 32 participants underwent repeated measurement of GFR by inulin clearance (mGFR). GFR was estimated by serum creatinine using the MDRD (eGFRMDRD) and CKD-EPI (eGFRCKD-EPI) equations four times over the course of one month. Performance was evaluated using measurements of bias (mean difference), precision (SD), and inaccuracy (proportion of eGFR that differed by >20 % of mGFR). Treatment and time effects on bias were evaluated using linear mixed effects models. ResultsAt baseline, participants (38 % female) were age 60 ± 8 years, had diabetes duration of 9 ± 7 years, HbA1c 56 ± 9 mmol/mol (7.2 ± 0.8 %), and BMI 31.0 ± 6.2 kg/m2. Mean mGFR was 113 ± 24, mean eGFRMDRD was 93 ± 12, and mean eGFRCKD-EPI was 94 ± 9 mL/min/1.73 m2. When 128 observations (32 participants measured 4 times) were evaluated, both equations substantially underestimated mGFR. For eGFRMDRD, mean bias was −21.5 mL/min/1.73 m2, precision was 22.7 mL/min/1.73 m2, and 46 % of observations differed by >20 %. Results were similar for eGFRCKD-EPI. No time or treatment effects on bias were observed. ConclusionsIn adults with type 2 diabetes and preserved renal function, eGFR equations underestimated mGFR, lacked precision and accuracy, and performance was lower at higher ranges of mGFR. Current eGFR equations by serum creatinine are inaccurate in adults with type 2 diabetes with preserved renal function, highlighting the necessity to develop new methods to measure kidney function at earlier stages of diabetic kidney disease.

Estimation of Myeloperoxidase and Some Biochemical Parameters in Patients with Chronic Kidney Disease

Background: Chronic kidney disease (CKD) is a complex disease impacting more than twenty million individuals in the United States. Progression of CKD is associated with a number of serious complications, including increased incidence of cardiovascular disease, hyperlipidemia, anemia and metabolic bone disease. CKD patients should be assessed for the presence of these complications and receive optimal treatment to reduce their morbidity and mortality. A multidisciplinary approach is required to accomplish this goal. Aim: The aim of the study to estimation myeloperoxidase activity in CKD patients and its association with other biochemical parameters (Creatinine and eGFR). Patients and Methods: A Case-control study is carried out Baghdad in the Imamian Kadhimian Medical City and Al- Karamah Teaching Hospital between August 2022 and March 2023. The number of CKD male under study was 60 male whose ages were between 25 to 50 years old. In addition, the control group consisted of 30 healthy volunteer males aged between 25 to 50 years and they did not have any diseases. Blood samples collected from each male for measurement of Myeloperoxidase (MPO) by Enzyme linked immunosorbent assay (ELISA), measure of serum creatinine by Abbott c4000 clinical chemistry analyzer and eGFR by MDRD equation. The study showed that the reduced mean level of myeloperoxidase (p value &lt;0.001) in patients group compared with control group, (19.9±6.82 ng/ml) and (42.4±4.98 ng/ml) respectively. Our study revealed that with increasing CKD stage, the myeloperoxidase levels decrease. Also, the elevated mean level of creatinine was 7.47±2.8 mg/dl in patient group was highly significant than control group 0.84±0.158 mg/dl p value &lt;0.001. The decrease mean of GFR was 9.42±3.53 in patients compared with controls 109±22.6 with high statistically significance (p&lt;0.001). The study found a positive correlation between MPO and GFR and negative correlation of serum myeloperoxidase with serum creatinine level in CKD patients.

#6128 IMPACT OF MANNOSE-BINDING LECTIN DEFICIENCY ON GRAFT SURVIVAL IN TRANSPLANT RECIPIENTS WITH IGAN

Abstract Background and Aims The progression of IgA nephropathy (IgAN) has been associated with Mannose -Binding Lectin levels (both excess or deficiency). The MBL deficiency, is associated with the rs5030737, the rs1800450 and the rs1800451, who represent the “O” allele. Since lectin pathway deregulation may impact on IgA progression on native kidney we hypothesized that the presence of the “O” allele and therefore MBL deficiency, could influence also the graft survival in recipients with a biopsy-proven diagnosis of IgAN on native kidneys. Therefore we investigated the role of MBL “O” allele in kidney transplant recipients with IgAN. Method We enrolled 32 kidney transplant recipients with biopsy-proven IgAN on the native kidney. The region in MBL encompassing the SNPs rs5030737, rs1800450 and rs1800451were amplified using PCR and analyzed by Sanger sequencing.Clinical data at baseline and during the follow-up were collected from patients’ records. An eGFR &amp;lt;60mL/min/1.73m2 (MDRD equation) was considered as main outcome at univariate and multivariate analyses. Results The 38% of patients carry the“O” allele and 62% of patients the “A” allele which is associated with the wild genotype. No difference between the two groups as for demographic features, donor and transplant-related variables has been found. Interestingly we found that patients with the “O” allele had a worse graft outcome (P = 0.01) during a mean follow-up of 151 months (Figure 1). The “O” allele was an independent predictor for the graft survival in a Cox survival analysis model adjusted for donor's and recipient's age, acute rejection, and disease recurrence (HR 0.046; 95% I.C. 0.005-0.423; P = 0.01). Moreover we found a link between the genetic background and the MBL serum level (Figure 2). Conclusion Our study suggest a potential role of the MBL deficiency in the long term graft dysfunction in kidney transplant recipient with IgAN.

#3617 APPLICATION OF CKD EPI 2021 EQUATION FOR ESTIMATION OF GLOMERULAR FILTRATION RATE (EGFR) TO AN ELDERLY KOREAN COHORT TO PREDICT MORTALITY

Abstract Background and Aims A new eGFR equation using serum creatinine (CKD-EPI 2021) without race were developed by Chronic Kidney Disease Epidemiology Collaboration in 2021. We projected the changes of eGFR and CKD prevalence in a prospective cohort of elderly Koreans, using current (MDRD equation and CKD-EPI 2009) and new equation (CKD-EPI 2021) Method This study was a part of the Korean Longitudinal Study on Health and Aging, which included a randomly selected, community-based, elderly population aged 65 years or more in a city of Korea, Seong-nam. The base line study was conducted from Sep. 2005 to Sep. 2006; the follow-up study, from May 2010 to March 2012, and the final survey about mortality and renal function, at Jan. 2023. Among 1,000 subjects originally included in the study, 984 subjects with baseline serum creatinine were included in this analysis. We compared the difference of eGFR and predictability of mortality and renal survival between values calculated by MDRD, CKD-EPI 2009, and CKD-EPI 2021. Serum creatinine was expressed as the IDMS-traceable creatinine. Results At baseline study, there were 436 males (44.3%). Age was 76.0 ± 9.1 years. Levels of eGFR at baseline study were 74.2 ± 21.4 ml/min/1.73 m2 by MDRD, 72.2 ± 16.9 ml/min/1.73 m2 by CKD-EPI2009, and 76.6 ± 17.3 ml/min/1.73 m2 by CKD-EPI2021. Values subtracted eGFRs by MDRD or CKD-EPI2009 from eGFR by CKD-EPEI2021 were 2.5 ± 10.1 ml/min/1.73 m2 and 4.5 ± 1.0 ml/min/1.73 m2, respectively. Between eGFRs by CKD-EPI2009 and CKD-EPI2021, the difference of eGFR was higher in females compared to males (p&amp;lt;0.001), was not different between subjects aged less than 75 years and more than 75 years (p = 0.139), and lowest in subject with &amp;lt;45 ml/min/1.73 m2 of eGFR by CKD-EPI2009 compared to subjects with other eGFR values (p&amp;lt;0.001). CKD stage was improved in 241 (24.5%) participants and was not changed in 743 (75.5%) using eGFR calculated by CKD-EPI2021 instead of CKD-EPI2009. Similar trend of eGFR difference between eGFRs calculated by MDRD and CKD-EPI2021. During 8.3 ± 6.2 years, 255 (25.9%) subjects were dead and 7 (0.7%) subjects had end stage renal disease (ESRD) before death. Any eGFR was an independent risk factors to mortality estimated by Cox's hazard proportional model adjusted by related factors. AUC to estimate survival by eGFRs was not different between eGFRs by CKD-EPI2021 and CKD-EPI2009 [0.662 (0.625-0.699) vs 0.658(0.620-0.695), p = 0.758], however, different between eGFRs by CKD-EPI2021 and MDRD [0.662 (0.625-0.699) vs 0584 (0.543-0.626), p&amp;lt;0.001]. AUC to estimate renal survival by eGFRs was not different between eGFRs by CKD-EPI2021 and CKD-EPI2009, also. Conclusion The eGFR calculated by CKD-EPI2021 showed higher value compared to eGFR calculated by CKD-EPI2009 or MDRD. The power to estimate mortality or renal survival was not different between eGFRs by CKD-EPI2021 and CKD-EPI2009.