scholarly journals A Novel Method for Accurate Quantification of Split Glomerular Filtration Rate Using Combination of Tc-99m-DTPA Renal Dynamic Imaging and Its Plasma Clearance

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Xiaoxi Pang ◽  
Fei Li ◽  
Shan Huang ◽  
Cheng’en Wang ◽  
Tao Zhang ◽  
...  
Keyword(s):  
Glomerular Filtration Rate ◽  
Glomerular Filtration ◽  
Filtration Rate ◽  
Plasma Clearance ◽  
Influence Factors ◽  
Dynamic Imaging ◽  
Consistency Test ◽  
Plasma Method ◽  
Coefficient Of Concordance ◽  
Double Blinded

Purpose. To precisely quantify split glomerular filtration rate by Tc-99m-DTPA renal dynamic imaging and plasma clearance in order to increase its consistency among doctors. Methods. Tc-99m-DTPA renal dynamic imaging was performed according to the conventional radionuclide renal dynamic imaging by five double-blinded doctors independently and automatically calculated split GFR, namely, gGFR. Moreover, the conventional radionuclide renal dynamic imaging was assessed to only outline the kidney, blank background, and automatically calculated split GFR, gGFR ′ . The total GFR value of patients, tGFR, was obtained by the double-plasma method. According to the formula, Precise   GFR   pGFR = gGF R ′ / gGF R ′ + gGF R ′ × tGFR . The precise GFR value of the divided kidney, pGFR, was calculated. The Kendall’s W test was used to compare the consistency of gGFR and pGFR drawn by five physicians. Results. According to Kendall’s W consistency test, Kendall’s coefficient of concordance was 0.834, p = 0.0001 using conventional method. The same five doctors used blank background again and the same standard Gates method to draw the kidneys, which automatically calculated gGFR ′ . Using input formula, the pGFR was calculated and Kendall’s W consistency test ( Kendal l ’ s   coefficient   of   concordance = 0.956 , p = 0.0001 ). Conclusion. The combination of Tc-99m-DTPA renal dynamic imaging combined with the double-plasma method could achieve accurate split GFR, and because of the omission of influence factors, the consistency of pGFR obtained by different doctors using this method was significantly higher than that of conventional Tc-99m-DTPA renal dynamic imaging.

Elevated Glomerular Filtration Rate (GFR) in Young Patients with Sickle Cell Anemia.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3745-3745
Author(s):  
Sherri A. Zimmerman ◽  
Jacqueline S. Davis ◽  
Nicole A. Mortier ◽  
Russell E. Ware
Keyword(s):  
Renal Function ◽  
Glomerular Filtration Rate ◽  
Young Children ◽  
Glomerular Filtration ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Filtration Rate ◽  
Plasma Clearance ◽  
Glomerular Hyperfiltration ◽  
Schwartz Equation

Abstract Nephropathy is a well-recognized complication of sickle cell anemia (SCA) that is associated with considerable morbidity and mortality. Sickle nephropathy begins early in life, with glomerular damage characterized by hyperfiltration and glomerulomegaly, as well as tubular damage characterized by hyposthenuria. School-aged children can develop proteinuria and one-third of patients will eventually develop chronic renal failure as adults. Among the earliest markers of sickle nephropathy is glomerular hyperfiltration, typically measured as an elevated glomerular filtration rate (GFR). To date, however, no formal measurements of GFR have been published in young children with SCA, and its feasibility and interpretation in this age group have not been demonstrated. As part of a prospective, single-institution, IRB-approved open-label protocol using hydroxyurea in toddlers with SCA, the pre-treatment GFR was measured using plasma clearance of 99-Tc DTPA. The goal of this procedure was to determine the onset of hyperfiltration among young children with SCA, to identify risk factors associated with its onset, and to investigate the potential benefit of hydroxyurea in improving or preserving renal function. After intravenous injection of the DTPA radiotracer, 3–5 mL aliquots of venous blood were removed at 1 and 3 hours post-injection and analyzed for plasma radioactivity. Because DTPA is filtered at the glomerulus without substantial metabolism, secretion, or reabsorption, the plasma clearance allows an accurate and precise GFR measurement. The GFR was also estimated using the Schwartz equation, where GFR = height (cm) x k/serum creatinine, with k=0.55 for children between ages 1 and 12 years. A total of 13 children with HbSS (3 females, 10 males) were enrolled in this study, none of whom had laboratory evidence of renal disease at the time of evaluation. One child could not complete the DTPA study due to inadequate venous access. For the remaining 12 children, baseline GFR measurements were performed at age 3.0 ± 0.8 years (range 1.7 to 4.4 years) without complications. The average GFR measurement (mean ± SD) by DTPA clearance was 140.3 ± 20 mL/min/1.73m2, median 133 mL/min/1.73m2, range 117.9 to 172.7 mL/min/1.73m2 (normal 100 ± 20 mL/min/1.73m2). The baseline DTPA GFR measurement was elevated above 150 mL/min/1.73m2 in 5 of the 12 children, including 4 of 7 over age 3 years, although there was no signfiicant correlation between GFR and age or fetal hemoglobin. GFR estimates by the Schwartz equation were modestly correlated with the DTPA GFR measurements (R2 = 0.32, p = 0.055) but were typically slightly higher than the corresponding DTPA measurements. Three children who completed 24 months of hydroxyurea therapy had post-treatment DTPA clearance studies that revealed stable GFR measurements (average increase = 5.6 mL/min/1.73m2). These results illustrate that GFR measurement by DTPA clearance can be performed without difficulty in young children with SCA, requiring only peripheral intravenous access. Glomerular hyperfiltration as a manifestation of renal damage begins early in life for children with SCA, with elevated GFR values observed in the toddler age range. The Schwartz equation provides an estimate of GFR but probably cannot be used in lieu of the DTPA clearance study. Treatment with hydroxyurea may preserve renal function by abrogating further GFR hyperfiltration.

Measurement of Glomerular Filtration Rate By Low-Dose Iopromide Plasma Clearance

2003 ◽  
Vol 44 (2) ◽  
pp. 162-165 ◽  
Author(s):  
N. Hackstein ◽  
C. Wiegand ◽  
A. C. Langheinrich ◽  
W. S. Rau
Keyword(s):  
Glomerular Filtration Rate ◽  
Glomerular Filtration ◽  
Filtration Rate ◽  
Plasma Clearance ◽  
Low Dose

Plasma clearance of iodine contrast media as a measure of glomerular filtration rate in critically ill patients

2001 ◽  
Vol 29 (8) ◽  
pp. 1544-1550 ◽  
Author(s):  
Christiane M. Erley ◽  
Birgit D. Bader ◽  
Elke D. Berger ◽  
Anika Vochazer ◽  
Jork J. Jorzik ◽  
...  
Keyword(s):  
Glomerular Filtration Rate ◽  
Contrast Media ◽  
Glomerular Filtration ◽  
Critically Ill ◽  
Critically Ill Patients ◽  
Filtration Rate ◽  
Plasma Clearance

Development of a modified sampling and calculation method for isotope plasma clearance assessment of the glomerular filtration rate in patients with cirrhosis and ascites

2013 ◽  
Vol 34 (11) ◽  
pp. 1124-1132 ◽  
Author(s):  
Fred Wickham ◽  
Maria T. Burniston ◽  
Elias Xirouchakis ◽  
Eleni Theocharidou ◽  
Carl A. Wesolowski ◽  
...  
Keyword(s):  
Glomerular Filtration Rate ◽  
Glomerular Filtration ◽  
Calculation Method ◽  
Filtration Rate ◽  
Plasma Clearance

scholarly journals A Novel Creatinine-Based Equation to Estimate Glomerular Filtration Rate in Chinese Population With Chronic Kidney Disease: Implications for DOACs Dosing in Atrial Fibrillation Patients

2021 ◽  
Vol 12 ◽  
Author(s):  
Ling-Yun Zhou ◽  
Wen-Jun Yin ◽  
Jun Zhao ◽  
Bi-Kui Zhang ◽  
Can Hu ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Chronic Kidney Disease ◽  
Renal Function ◽  
Glomerular Filtration Rate ◽  
Kidney Disease ◽  
Glomerular Filtration ◽  
Filtration Rate ◽  
Linear Regression Analysis ◽  
Dynamic Imaging ◽  
Adverse Outcomes

Background: Over/under-estimating renal function may increase inappropriate dosing strategy associated adverse outcomes; however, previously reported equations to estimate renal function have limited accuracy in chronic kidney disease (CKD) patients. Consequently, we intended to develop a novel equation to precisely estimate renal function and subsequently guide clinical treatment for CKD patients.Methods: A novel approach, Xiangya-s equation, to estimate renal function for CKD patients was derived by linear regression analysis and validated in 1885 patients with measured glomerular filtration rate (mGFR) < 60 ml/min/1.73 m2 by renal dynamic imaging at three representative hospitals in China, with the performance evaluated by accuracy, bias and precision. In the meanwhile, 2,165 atrial fibrillation (AF) patients who initiated direct oral anticoagulants (DOACs) between December 2015 and December 2018 were identified and renal function was assessed by estimated creatinine clearance (eCrCl). Events per 100 patient-years was calculated. Cox proportional hazards regression was applied to compare the incidence of outcomes of each group.Results: Xiangya-s equation demonstrated higher accuracy, lower bias and improved precision when compared with 12 creatinine-based and 2 CysC-based reported equations to estimate GFR in multi-ethnic Chinese CKD patients. When we applied Xiangya-s equation to patients with AF and CKD prescribed DOACs, wide variability was discovered in eCrCl calculated by the Cockcroft-Gault (CG), Modification of Diet in Renal Disease Study (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), Xiangya equation which we had developed for generally patients and Xiangya-s equations, which persisted after grouping by different renal function stages. Equation choice affected drug-dosing adjustments, with the formulas agreeing for only 1.19%, 5.52%, 33.22%, 26.32%, and 36.61% of potentially impacted patients for eCrCl cutoffs of <15, <30, 15–49, 30–49, ≥50 ml/min, respectively. Relative to CG equation, accordance in DOACs dosage was 81.08%, 88.54%, 62.25%, and 47.68% for MDRD, CKD-EPI, Xiangya and Xiangya-s equations for patients with CrCl < 50 ml/min (eCrCl cutoffs of <30, 30–49, ≥50 ml/min), respectively. Reclassification of renal function stages by Xiangya-s equation was significantly associated with stroke or systemic embolism, non-major clinically relevant bleeding and any bleeding events.Conclusion: Xiangya-s equation provides more accurate GFR estimates in Chinese CKD patients who need consecutive monitoring of renal function, which may assist clinicians in choosing appropriate drug dosages.

scholarly journals Revised Equations to Estimate Glomerular Filtration Rate from Serum Creatinine and Cystatin C in China

2019 ◽  
Vol 44 (4) ◽  
pp. 553-564 ◽  
Author(s):  
Min Yang ◽  
Yonghua Zou ◽  
Tong Lu ◽  
Yule Nan ◽  
Jianying Niu ◽  
...  
Keyword(s):  
Glomerular Filtration Rate ◽  
Serum Creatinine ◽  
Glomerular Filtration ◽  
Cystatin C ◽  
Filtration Rate ◽  
Dynamic Imaging ◽  
Imaging Method ◽  
Validation Data ◽  
Data Set ◽  
Precision And Accuracy

Aim: Our previous study demonstrated that the cystatin C-based chronic kidney disease (CKD)-EPI equation and combined by serum creatinine (CKD-EPIscr-cys) had better capability to accurately evaluate glomerular filtration rate in the CKD participants. Considering that the accuracy of estimated glomerular filtration rate (eGFR) remains less ideally, it is essential to modify the equation by including the Chinese eGFR racial factor in order to improve its performance. Methods: Two prospective cohorts were enrolled in 2 medical centers. New equations were developed in 529 participants and validated in 313 participants. Reference glomerular filtration rate (rGFR) was taken by 99mTc-DTPA renal dynamic imaging method (Gates method). The primary outcomes of this study were bias, precision (interquartile range of difference [IQR]), and accuracy (the proportion of eGFR within 30% of rGFR [P30] and root mean square error [RMSE]) of eGFR versus rGFR. Results: In a development data set, Chinese coefficients for CKD-EPIscr (C-CKD-EPIscr), CKD-EPIcys (C-CKD-EPIcys), and CKD-EPIscr-cys (C-CKD-EPIscr-cys) were 0.871, 0.879, and 0.891, respectively. In a validation data set, C-CKD-EPIcys was the most accurate with highest P30 value (62.3%), relative lowest IQR (15.45), and RMSE (0.80) among 6 equations, though the bias of C-CKD-EPIcys was not better than CKD-EPIcys. C-CKD-EPIscr and C-CKD-EPIscr-cys equations were improved in bias (p < 0.001), ­precision, and accuracy (p = 0.004 and <0.001 for P30) compared with CKD-EPIscr and CKD-EPIscr-cys. Conclusion: C-CKD-EPIcys was the most accurate with the highest P30 value, relative lowest IQR, and RMSE among 6 equations. C-CKD-EPIscr and C-CKD-EPIscr-cys equations were improved in bias, precision, and accuracy. Other external validation of these equations is needed.

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