Total Glomerular Filtration Rate Research Articles

Clinical trial designs to assess treatment effects on glomerular filtration rate decline

Glomerular filtration rate (GFR) decline is used as surrogate endpoint for kidney failure. Interventions that reduce chronic kidney disease (CKD) progression often exert acute GFR reductions which differ from their long-term benefits and complicate the estimation of long-term benefit. Here, we assessed the utility of two alternative trial designs (wash-out design and active run-in randomized withdrawal design) that attempt to exclude the impact of acute effects. Post-hoc analyses of two clinical trials that characterized the effect of an intervention with acute reductions in GFR were conducted. The two trials included a wash-out period (EMPAREG-Outcome testing empagliflozin vs placebo) or an active run-in period with a randomized withdrawal (SONAR testing atrasentan vs placebo). We compared the drug effect on GFR decline calculated from the first on-treatment visit to the end-of-treatment (chronic effect in a standard randomized trial design) with GFR change calculated from randomization to end-of-wash-out, or GFR change from treatment specific baseline GFR values (GFR at start-of-run-in for placebo and end-of-run-in for atrasentan) until end-of-treatment. The effect of empagliflozin versus placebo on chronic GFR slope was 1.72 (95% confidence interval 1.49-1.94) mL/min/1.73m2 /year, similar to total GFR decline from baseline to the end of wash-out period using a linear mixed model 1.64 (1.44-1.85) mL/min/1.73m2 /year). The effect of atrasentan versus placebo on chronic GFR slope was 0.72 (0.32-1.11) mL/min/1.73m2 /year, similar to total slope from a single slope model when estimated from treatment specific baseline GFR values 0.77 (0.39-1.14) mL/min/1.73m2 /year). Statistical power of the two designs outperformed the standard randomized design. Thus, wash-out and active-run-in randomized-withdrawal trial designs are appropriate models to compute treatment effects on GFR decline.

Functional recovery after partial nephrectomy in a solitary kidney

ObjectivesPartial nephrectomy (PN) is the reference standard for renal mass in a solitary kidney (RMSK), although factors determining functional recovery in this setting remain poorly defined. Patients/MethodsSingle center, retrospective analysis of 841 RMSK patients (1975–2022) managed with PN with functional data, including 361/435/45 with cold/warm/zero ischemia, respectively. A total of 155 of these patients also had necessary studies for detailed analysis of parenchymal volume preserved. Acute kidney injury (AKI) was classified by RIFLE (Risk/Injury/Failure/Loss/Endstage). Recovery-from-ischemia (Rec-Ischemia) was defined as glomerular filtration rate (GFR) saved normalized by parenchymal volume saved. Logistic regression identified predictive factors for AKI and predictors of Rec-Ischemia were analyzed by multivariable linear regression. ResultsOverall, median preoperative GFR was 56.7 ml/min/1.73m2 and new-baseline and 5-year GFRs were 43.1 and 44.5 ml/min/1.73m2, respectively. Median follow-up was 55 months; 5-year dialysis-free survival was 97%. In the detailed analysis cohort, a primary focus of this study, median warm (n = 70)/cold (n = 85) ischemia times were 25/34 minutes, respectively; and median preoperative, new-baseline and 5-year GFRs were 57.8, 45.0, and 41.7 ml/min/1.73m2, respectively. Functional recovery correlated strongly with parenchymal volume preserved (r = 0.84, p < 0.001). Parenchymal volume loss accounted for 69% of the total median GFR decline associated with PN, leaving only 3 to 4 ml/min/1.73m2 attributed to ischemia and other factors. AKI occurred in 52% of patients and the only independent predictor of AKI was ischemia time. Independent predictors of reduced Rec-Ischemia were increased age, warm ischemia, and AKI. ConclusionThe main determinant of functional recovery after PN in RMSK is parenchymal volume preservation. Type/duration of ischemia, AKI, and age also correlated, although altogether their contributions were less impactful. Our findings suggest multiple opportunities for optimizing functional outcomes although preservation of parenchymal volume remains predominant. Long-term function generally remains stable with dialysis only occasionally required.

A Single-Center Study on the Clinical Profiles and Ultrasonographic Assessments of Living Kidney Donors in the Marathwada Region of Maharashtra.

Living donor kidney transplantation plays a vital role in renal replacement therapy, particularly in India, where a substantial increase in kidney transplants has been observed. Thorough assessments of living kidney donors are crucial, focusing on parameters such as kidney size and glomerular filtration rate (GFR). Despite the importance of GFR in donor assessments, there is a noticeable lack of data on normal GFR ranges in the Indian population. This study aims to address the gap in knowledge by establishing a reference range for GFR in healthy kidney donors from the Marathwada region of Maharashtra. The research also explores the clinical profiles and ultrasonographic features of living kidney donors. A retrospective analysis was conducted at the Mahatma Gandhi Mission (MGM) Medical College and Hospital in Aurangabad, involving 134 living kidney donors. Inclusion criteria encompassed healthy donors with a BMI of less than 30 kg/m², while donors with uncontrolled hypertension, diabetes, microalbuminuria, or a measured GFR below 70 mL/min/1.73 m² were excluded. Comprehensive medical histories, demographic parameters, and ultrasonographic assessments were conducted, with GFR measured using 99M technetium diethylenetriamine pentaacetate scans. The study reveals that the majority of donors were females (80.6%), and the highest number fell within the 41-50 age group. Parents constituted the primary donor category (68.7%), reflecting a familial inclination toward organ donation. Ultrasonographic assessments indicated larger kidney sizes compared to other studies, suggesting regional or population-specific differences. The mean GFR for the right and left kidneys, as well as the total GFR, was within the expected range. The negative correlation between age and GFR emphasizes the need to consider age in donor assessments. The findings emphasize the unique features of this population, including a higher average age, female preponderance, and larger kidney sizes. The study contributes to the understanding of living kidney donors' profiles in the region and highlights the importance of individualized assessments in the donor selection process.

Clinical study of renal artery cold perfusion combined with laparoscopic nephron retention in the treatment of complex renal angiomyolipoma.

The aim of this study is to summarize the surgical experience of renal artery cold perfusion combined with laparoscopic nephron preserving surgery for the treatment of complex renal angiomyolipoma and to evaluate the safety and feasibility of this surgical protocol. Clinical data of nine patients who received renal artery cold perfusion combined with laparoscopic nephron preserving surgery for complex renal angiomyolipoma in our hospital from February 2017 to August 2020 were retrospectively analyzed. The study parameters included imaging findings, total renal function before and after surgery, glomerular filtration rate (GFR) of affected kidney before and after surgery, and related complications. Eight of the nine patients successfully completed the operation, one patient was intolerant to renal artery balloon implantation, and the success rate of the operation was 88.89%. The mean maximum tumor diameter was 6.8 cm, and RENAL score was 7 points. Postoperative total renal function and GFR of the affected kidney had no significant changes compared with that before surgery, and imaging examination showed no tumor residue or recurrence. This surgical procedure is safe and feasible for complex renal angiomyolipoma and can be used as a surgical option for renal hamartoma. The long-term effect needs to be confirmed by further studies.

Assessment of the kidney functional state prior and after partial nephrectomy for a unilateral tumor using mathematical processing of computed tomography data with contrast enhancement

Background. According to the contemporary data available contrast-enhanced computed tomography can be used to assess total and split kidney function. The Urology Clinic of the I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia (Sechenov University) utilizes mathematical processing of computed tomography data for the assessment of split kidney function.Aim. To evaluate the effect of main renal artery clamping (warm ischemia time) during partial nephrectomy for a unilateral tumor on the kidney function.Materials and methods. 33 patients of both sexes who underwent partial nephrectomy for unilateral kidney tumor were enrolled in the study. Prior to and 3–6 months after the surgery, 3D glomerular filtration rate (GFR), 3D perfusion, 3D volume of the renal parenchyma were evaluated by mathematical processing of computed tomography data with contrast enhancement. As well as that the dynamics of the total GFR (CKD-EPI equation) and total volume of the kidneys were assessed.Results. No significant changes were registered for both general functional renal parameters (creatinine level, total GFR, total volume of functioning renal parenchyma) and split 3D GFR. There were significant differences in 3D perfusion and kidney parenchyma volume prior and after partial nephrectomy.Conclusion. The results of the research highlight good reserve capacity the kidneys after partial nephrectomy with main renal artery clamping. The evidence that the non-operated kidney takes over the function of the resected kidney is based on the fact that there is an increase in its perfusion and volume of the kidney in the postoperative period. This state can also be regarded as a redistribution of functional loads between the kidneys, which is an adaptive mechanism in the postoperative period.

A meta-analysis of GFR slope as a surrogate endpoint for kidney failure.

Glomerular filtration rate (GFR) decline is causally associated with kidney failure and is a candidate surrogate endpoint for clinical trials of chronic kidney disease (CKD) progression. Analyses across a diverse spectrum of interventions and populations is required for acceptance of GFR decline as an endpoint. In an analysis of individual participant data, for each of 66 studies (total of 186,312 participants), we estimated treatment effects on the total GFR slope, computed from baseline to 3 years, and chronic slope, starting at 3 months after randomization, and on the clinical endpoint (doubling of serum creatinine, GFR < 15 ml min-1 per 1.73 m2 or kidney failure with replacement therapy). We used a Bayesian mixed-effects meta-regression model to relate treatment effects on GFR slope with those on the clinical endpoint across all studies and by disease groups (diabetes, glomerular diseases, CKD or cardiovascular diseases). Treatment effects on the clinical endpoint were strongly associated with treatment effects on total slope (median coefficient of determination (R2) = 0.97 (95% Bayesian credible interval (BCI) 0.82-1.00)) and moderately associated with those on chronic slope (R2 = 0.55 (95% BCI 0.25-0.77)). There was no evidence of heterogeneity across disease. Our results support the use of total slope as a primary endpoint for clinical trials of CKD progression.

PD43-03 FUNCTIONAL RECOVERY AFTER PARTIAL NEPHRECTOMY IN A SOLITARY KIDNEY

You have accessJournal of UrologyCME1 Apr 2023PD43-03 FUNCTIONAL RECOVERY AFTER PARTIAL NEPHRECTOMY IN A SOLITARY KIDNEY Worapat Attawettayanon, Yosuke Yasuda, JJ Zhang, Nityam Rathi, Carlos Munoz-Lopez, Kieran Lewis, Ben Ponvilawan, Snehi Sha, Jianbo Li, Joao Accioly, Rebecca Campbell, Joseph Zabell, Jihad Kaouk, Georges-Pascal Haber, Mohamad Eltemamy, Venkatesh Krishnamurthi, Robert Abouassaly, Christopher Weight, and Steven Campbell Worapat AttawettayanonWorapat Attawettayanon More articles by this author , Yosuke YasudaYosuke Yasuda More articles by this author , JJ ZhangJJ Zhang More articles by this author , Nityam RathiNityam Rathi More articles by this author , Carlos Munoz-LopezCarlos Munoz-Lopez More articles by this author , Kieran LewisKieran Lewis More articles by this author , Ben PonvilawanBen Ponvilawan More articles by this author , Snehi ShaSnehi Sha More articles by this author , Jianbo LiJianbo Li More articles by this author , Joao AcciolyJoao Accioly More articles by this author , Rebecca CampbellRebecca Campbell More articles by this author , Joseph ZabellJoseph Zabell More articles by this author , Jihad KaoukJihad Kaouk More articles by this author , Georges-Pascal HaberGeorges-Pascal Haber More articles by this author , Mohamad EltemamyMohamad Eltemamy More articles by this author , Venkatesh KrishnamurthiVenkatesh Krishnamurthi More articles by this author , Robert AbouassalyRobert Abouassaly More articles by this author , Christopher WeightChristopher Weight More articles by this author , and Steven CampbellSteven Campbell More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003353.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Partial nephrectomy (PN) is the reference standard for management of renal mass in a solitary kidney (RMSK), although factors determining functional recovery in this setting remain ill-defined. METHODS: 841 RMSK patients (1975-2022) managed with PN with functional data were identified, including 361/435/45 with cold/warm/zero ischemia, respectively. 155 patients also had necessary studies for detailed analysis of parenchymal volume preserved. Acute kidney injury (AKI) was classified by RIFLE (Risk/Injury/Failure/Loss/Endstage). Recovery from ischemia (Rec-Ischemia) was defined as glomerular filtration rate (GFR) saved normalized by parenchymal volume saved. Multivariable analysis was utilized to identify predictive factors for AKI and Rec-Ischemia. RESULTS: Overall, median preoperative GFR was 56.7ml/min/1.73m2 and median new baseline and 5-year GFRs were 43.1 and 44.5 ml/min/1.73m2, respectively. Median follow-up was 55 months; 5-year dialysis-free survival was 97%. In the detailed analysis cohort, median warm (n=70)/cold(n=85) ischemia times were 25/34 minutes, respectively, and median preoperative, new baseline and 5-year GFRs were 57.8, 45.0 and 41.7 ml/min/1.73m2, respectively. Functional recovery correlated strongly with parenchymal volume preserved (r=0.84, p<0.001). Loss of parenchymal volume accounted for 69% of the total median GFR decline associated with PN, leaving only an average of 3-4 ml/min/1.73m2 due to ischemia and other factors. AKI occurred in 52% of patients and was Grade 2/3 in 20%. The only independent predictor of AKI was ischemia time, and independent predictors of Rec-Ischemia were age, warm ischemia, and AKI grade. CONCLUSIONS: The main determinant of functional recovery after PN in RMSK is parenchymal volume preservation. Type and duration of ischemia, AKI, and age also correlated, although altogether their contributions were less impactful. Our findings suggest multiple opportunities for optimizing functional outcomes although preservation of vascularized parenchymal volume remains predominant. Long-term function generally remains stable with dialysis only occasionally required. Source of Funding: none © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e1118 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Worapat Attawettayanon More articles by this author Yosuke Yasuda More articles by this author JJ Zhang More articles by this author Nityam Rathi More articles by this author Carlos Munoz-Lopez More articles by this author Kieran Lewis More articles by this author Ben Ponvilawan More articles by this author Snehi Sha More articles by this author Jianbo Li More articles by this author Joao Accioly More articles by this author Rebecca Campbell More articles by this author Joseph Zabell More articles by this author Jihad Kaouk More articles by this author Georges-Pascal Haber More articles by this author Mohamad Eltemamy More articles by this author Venkatesh Krishnamurthi More articles by this author Robert Abouassaly More articles by this author Christopher Weight More articles by this author Steven Campbell More articles by this author Expand All Advertisement PDF downloadLoading ...

N1-Methylnicotinamide: The Mysterious Anti-aging Actor in Renal Transplantation.

The fast global aging of people worldwide is a crucial demographic trend. According to evidence, Americans aged 65 and above will compose 21.6% of the population by 2040. During the aging process, the kidney undergoes gradual functional decrease, which turned out to be a forthcoming problem in clinical practice. Age-related decrease in renal function, evaluated by total glomerular filtration rate (GFR), which has been shown to drop by approximately 5-10% per decade after the age of 35. The sustaining extended period renal homeostasis is the main purpose of any therapeutic options intended for delaying or even reversing the aging kidney. The renal transplant has been regarded as the common alternative for kidney replacement therapy for elderly patients with end-stage renal disease (ESRD). In the last few years, considerable progress has been made to find novel therapeutic options for alleviating renal aging, in particular, calorie restriction and pharmacologic therapy. Nicotinamide N-methyltransferase is an enzyme responsible for generating N1-Methylnicotinamide (MNAM), notorious for its anti-diabetic, anti-thrombotic, and anti-inflammatory activity. MNAM is one of the important factors regarded as in vivo probes for evaluating the activity of some renal drug transporters. Furthermore, it has been shown to have therapeutic potential in the pathogenesis of proximal tubular cell damage and tubulointerstitial fibrosis. In this article, in addition to addressing the role of MNAM in renal function, we also explained its anti-aging effects. We conducted an in-depth investigation of the urinary excretion of MNAM and its metabolites, especially N1-methyl-2-pyridone-5- carboxamide (2py) in RTR. The excretion of MNAM and its metabolite, 2py, was inversely correlated with the risk of all-cause mortality in renal transplant recipients (RTR), independent of possible confounders. Therefore, we have shown that the reason for the lower mortality rate in RTR who had higher urinary excretion of MNAM and 2py may be related to the anti- aging effects of MNAM through transiently generating low levels of reactive oxygen species, stress resistance and the activation of antioxidant defense pathways.

Correlation of Differential Function and Glomerular Filtration Rate Estimated from Computed Tomography based Renal Volume and Diuretic Renogram in Living Renal Donor

Introduction: In renal transplant, serum creatinine and isotope studies are used for determination of donor glomerular filtration rate (GFR). Studies have shown computed tomography measured renal volume can also be used. Our main objective was to assess the accuracy of volume based estimated GFR (vGFR) with diethylene triamine penta acetic acid (DTPA) measured GFR in living kidney donors. Methods: An observational analytical study was conducted from July 2018 to June 2019 in Department of Urology and Kidney Transplant Surgery and Department of Radiodiagnosis in Tribhuvan University Teaching Hospital where a total of 38 eligible potential donors were evaluated and serum creatinine level, computed tomography with contrast and DTPA renogram were used to measure GFR and differential function. Results: The mean age of the donors were 42.8±10.9 years with 70% of donors being females. Renal volume was not statistically different between male and female donors. There was moderate correlation between volume based and DTPA based GFR (r=0.76) and differential function (r=0.71). Compared to creatinine, volume based GFR estimate showed better correlation to DTPA renogram. There was no significant difference in differential function estimated by DTPA and volume based estimates (p = 0.96). The upper and lower limit of agreement between the volume based and DTPA based differential function was –4.7 and 4.6 respectively. Conclusion: GFR measurement by CT volume overestimates total GFR compared to DTPA renogram but it has better correlation than creatinine based estimates. It can be used to estimate the differential function of the donor kidney.

A novel rotation method with variable-angle anterior probe for correcting the depth of the kidney to optimize renal dynamic imaging

PurposeWe aimed to investigate the effect and significance of the rotation method with variable-angle anterior probe corrected for the depth of two kidneys on the determination of glomerular filtration rate (GFR) in total and single kidneys by the renal dynamic imaging Gates method.MethodsSeventy-two patients who underwent dynamic renal imaging by the rotation method and abdominal CT in our hospital were collected in the present study. CT scanning, rotation method, Tonnesen's formula, and Li-Qian's formula were compared in terms of the depth of two kidneys, the depth difference between the two kidneys, and the total renal and single GFR obtained by substituting the renal depth values into Gates' formula.Results①The depth of kidneys and GFR: Compared to CT, Tonnesen's formula significantly underestimated the depth of both kidneys and the total and single renal GFR (P < 0.05). No significant differences were found in the depth of both kidneys and the total and single renal GFR between Li-Qian's formula and the rotation method (P > 0.05), with a strong agreement and with the least bias in the values measured by the rotation method. ②Renal depth difference: Compared to CT, Tonnesen's formula and Li-Qian's formula underestimated the difference in depth between the two kidneys (P < 0.05). None of the differences were statistically significant based on the rotation method (P > 0.05). The depth difference was positively correlated with the resulting changes in single renal function (|R(CT)-R(Li-Qian)|) and (|R(Rotation)-R(Li-Qian)|) (r = 0.881, 0.641, P < 0.001). As the depth difference increased, Li-Qian's formula could not visualize changes in single renal function accurately. In contrast, the accuracy of the rotation method in assessing single renal function remains unaffected.ConclusionThe rotation method obtains an accurate depth and depth difference between the two kidneys without additional CT radiation, enhancing the accuracy of the Gates method for determining total and single renal GFR.Trial registration Medical Ethics Committee of First Hospital of Shanxi Medical University, 2021BAL0146. Registered 12 January 2021.

Deep regression using 99mTc-DTPA dynamic renal imaging for automatic calculation of the glomerular filtration rate.

To develop and evaluate an artificial intelligence (AI) system that can automatically calculate the glomerular filtration rate (GFR) from dynamic renal imaging without manually delineating the regions of interest (ROIs) of kidneys and the corresponding background. This study was a single-center retrospective analysis of the data of 14,634 patients who underwent 99mTc-DTPA dynamic renal imaging. Two systems based on convolutional neural networks (CNN) were developed and evaluated: sGFRa predicts the radioactive counts of ROIs and calculates GFR using the Gates equation and sGFRb directly predicts GFR from dynamic renal imaging without using other information. The root-mean-square error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE), and R2 were used to evaluate the performance of our approach. sGFRa achieved an RMSE of 5.05, MAE of 4.03, MAPE of 6.07%, and R2 of 0.93 for total GFR while sGFRb achieved an RMSE of 7.61, MAE of 5.92, MAPE of 8.92%, and R2 of 0.85 for total GFR. The accuracy of sGFRa and sGFRb in determining the stage of chronic kidney disease was 87.41% and 82.44%, respectively. The findings of sGFRa show that automatic GFR calculation based on CNN and using dynamic renal imaging is feasible and efficient and, additionally, can aid clinical diagnosis. Furthermore, the promising results of sGFRb demonstrate that CNN can predict GFR from dynamic renal imaging without additional information. • Our CNN-based AI systems can automatically calculate GFR from dynamic renal imaging without manually delineating the ROIs of kidneys and the corresponding background. • sGFRa accurately predicted the radioactive counts of ROIs and calculated GFR using the Gates method. • sGFRb-predicted GFR directly without any parameters related to the Gates equation.

Dynamic changes of renal cortical blood perfusion before and after percutaneous transluminal renal artery stenting in patients with severe atherosclerotic renal artery stenosis.

Background:This study aims to observe the dynamic changes of renal artery (RA) disease and cortical blood perfusion (CBP) evaluated by contrast-enhanced ultrasound (CEUS) after percutaneous transluminal renal artery stenting (PTRAS) in patients with severe atherosclerotic renal artery stenosis (ARAS) and to analyze the relationship between CBP and prognosis.Methods:This was a single-center retrospective cohort study. A total of 98 patients with unilateral severe ARAS after successful PTRAS in Beijing Hospital from September 2017 to September 2020 were included. According to renal glomerular filtration rate (GFR) detected by radionuclide imaging at 12 months after PTRAS, all patients were divided into the poor prognosis group (n = 21, GFR decreased by ≥20% compared with baseline) and the control group (n = 77, GFR decreased by < 20% or improved compared with baseline). Renal artery stenosis was diagnosed by digital subtraction angiography, and renal CBP was evaluated by CEUS using TomTec Imaging Systems (Germany) before PTRAS, at 6 months and 12 months after discharge. The receiver operating characteristic (ROC) curve with area under the curve (AUC) was used to analyze the predictive value of CBP parameters, including area under ascending curve (AUC1), area under the descending curve (AUC2), rising time (RT), time to peak intensity (TTP), maximum intensity (IMAX), and mean transit time (MTT) for poor prognosis.Results:Among the 98 patients, there were 52 males (53.1%), aged 55–74 years old, with an average age of 62.1 ± 8.7 years, and an average artery stenosis of 82.3 ± 12.9%. The poor prognosis group was associated with significantly increased incidence of diabetes (76.2% vs. 41.6%), and lower levels of GFR of the stenotic kidney (21.8 mL/min vs. 25.0 mL/min) and total GFR (57.6 mL/min vs. 63.7 mL/min) (all P < 0.05), compared with the control group (P < 0.05). In addition, the rate of RA restenosis was significantly higher in the poor prognosis group than in the control group (9.5% vs. 0, χ2 = 9.462, P = 0.002). Compared with the control group, the poor prognosis group was associated with significantly decreased baseline AUC1 and AUC2, and extended duration of TTP and MTT (P < 0.05). At 6 months and 12 months of follow-up, patients in the control group were associated with markedly increased AUC1, AUC2, and IMAX, and shorter duration of RT and MTT (P < 0.05). The ROC curve showed that the predictive values of AUC1, AUC2, RT, TTP, IMAX, and MTT for poor prognosis were 0.812 (95% CI: 0.698–0.945), 0.752 (95% CI: 0.591–0.957), 0.724 (95% CI: 0.569–0.961), 0.720 (95% CI: 0.522–0.993), 0.693 (95% CI: 0.507–0.947), and 0.786 (95% CI: 0.631–0.979), respectively.Conclusions:Preoperative renal CBP in severe ARAS patients with poor prognosis is significantly reduced, and does not show significant improvement after stent treatment over the first year of follow-up. The parameter AUC1 may be a good predictor for renal dysfunction after PTRAS in severe ARAS patients.Trial Registration:ChiCTR.org.cn, ChiCTR1800016252.

Protective effect of sacubitril/valsartan (Entresto) on kidney function and filtration barrier injury in a porcine model of partial nephrectomy.

Kidney surgery often includes organ ischaemia with a risk of acute kidney injury. The present study tested if treatment with the combined angiotensin II-angiotensin II receptor type 1 and neprilysin blocker Entresto (LCZ696, sacubitril/valsartan) protects filtration barrier and kidney function after ischaemia and partial nephrectomy (PN) in pigs. Single kidney glomerular filtration rate (GFR) by technetium-99m diethylene-triamine-pentaacetate clearance was validated (n=6). Next, four groups of pigs were followed for 15 days (n=24) after PN (one-third right kidney, 60min ischaemia) + Entresto (49/51mg/day; n=8), PN+vehicle (n=8), sham+Entresto (49/51mg/day; n=4) and sham+vehicle (n=4). GFR, diuresis and urinary albumin were measured at baseline and from each kidney after 15 days. The sum of single-kidney GFR (right 25± 6mL/min, left 31± 7mL/min) accounted for the total GFR (56± 14mL/min). Entresto had no effect on baseline blood pressure, p-creatinine, mid-regional pro-atrial natriuretic peptide (MR-proANP), heart rate and diuresis. After 15 days, Entresto increased GFR in the uninjured kidney (+23± 6mL/min, P<.05)and reduced albuminuria from both kidneys. In the sham group, plasma MR-proANP was not altered by Entresto; it increased to similar levels 2 h after surgery with and without Entresto. Fractional sodium excretion increased with Entresto. Kidney histology and kidney injury molecule-1 in cortex tissue were not different. In conclusion, Entresto protects the filtration barrier and increases the functional adaptive response of the uninjured kidney.

Glomerular hyperfiltration.

Circulating blood is filtered across the glomerular barrier to form an ultrafiltrate of plasma in the Bowman's space. The volume of glomerular filtration adjusted by time is defined as the glomerular filtration rate (GFR), and the total GFR is the sum of all single-nephron GFRs. Thus, when the single-nephron GFR is increased in the context of a normal number of functioning nephrons, single glomerular hyperfiltration results in 'absolute' hyperfiltration in the kidney. 'Absolute' hyperfiltration can occur in healthy people after high protein intake, during pregnancy and in patients with diabetes, obesity or autosomal-dominant polycystic kidney disease. When the number of functioning nephrons is reduced, single-nephron glomerular hyperfiltration can result in a GFR that is within or below the normal range. This 'relative' hyperfiltration can occur in patients with a congenitally reduced nephron number or with an acquired reduction in nephron mass consequent to surgery or kidney disease. Improved understanding of the mechanisms that underlie 'absolute' and 'relative' glomerular hyperfiltration in different clinical settings, and of whether and how the single-nephron haemodynamic and related biomechanical forces that underlie glomerular hyperfiltration promote glomerular injury, will pave the way toward the development of novel therapeutic interventions that attenuate glomerular hyperfiltration and potentially prevent or limit consequent progressive kidney injury and loss of function.

Динамика объема функционирующей паренхимы и раздельной почечной функции до и после резекции почки по поводу опухоли

Objective. To assess functions of each kidney in dynamics using mathematical analysis of contrast-enhanced computed tomography findings in patients with unilateral kidney tumors. Patients and methods. We present preliminary results of a prospective study within the protocol "Assessment of the functioning renal parenchyma volume and functions of each kidney in patients with tumors before and after resection" conducted in the Institute of Urology and Human Reproductive Health, I.M.Sechenov First Moscow State Medical University. This study included 20 patients of both sexes who had undergone resection of unilateral kidney tumors with compression of the main renal artery. We performed mathematical analysis of contrast-enhanced computed tomography findings before surgery and 3–6 months postoperatively to evaluate functions of each kidney. In addition to that, we measured the dynamics of total glomerular filtration rate (GFR) using a special formula. Results. We observed no significant dynamics in any total functional renal parameters (creatinine level, total GFR, total functioning renal parenchymal volume) and in 3D-GFR of each kidney. However, there were significant differences in the dynamics of functional parameters measured for each kidney individually, including 3D renal perfusion and functioning parenchyma volume of each kidney. The volume of functioning renal parenchyma in the affected kidney decreased significantly (p = 0.006). In the subgroup with no lesions, we observed no significant dynamics (p = 0.236). Changes in perfusion affected both sides. Conclusion. We found no significant changes in the total kidney function after surgery, which suggests a sufficient reserve capacity of this paired organ. Increased postoperative perfusion in the intact kidney is likely to reflect redistribution of functional loads between the kidneys and can be considered as an adaptive mechanism. This hypothesis is also confirmed by redistribution of the functioning parenchyma volume 3–6 months postoperatively. The intact kidney probably compensates the loss of function in the affected kidney.

Efficacy analysis of retroperitoneal laparoscopic selective renal artery branch occlusion and nephron sparing surgery for ≥ T1b stage renal carcinoma

Objective: To investigate the safety and efficacy of retroperitoneal laparoscopic selective renal artery branch occlusion with nephron sparing surgery in patients with renal carcinoma of stage ≥ T1b. Methods: From July 2016 to September 2020, 35 patients with renal cancer ≥T1b underwent retroperitoneoscopic nephron sparing surgery in the First Affiliated Hospital of Shenzhen University. The surgical methods were retroperitoneoscopic nephron sparing surgery with total renal artery occlusion (group A) or selective renal artery branch occlusion (group B). Operation time, heat ischemia time, blood transfusion rate, positive margin rate, intraoperative blood loss, postoperative complications and length of hospital stay were compared between the two groups, and the total glomerular filtration rate (GFR) and the single-nephron glomerular filtration rate (sGFR) of the offected kidneys were compared between the two groups before, 3 months after and 12 months after surgery. Results: Among the 35 patients, 19 were male and 16 were female, aged (55.7±8.4) years and the body mass index is (24.6±3.1) kg/m2. The tumor diameter was (54.7±10.3) mm. The difference was statistically significant of operative time between group A and B [(103.5±14.3) vs (123.2±14.1) min,P=0.003]. There were no significant differences in thermal ischemia time, blood transfusion rate, positive margin, intraoperative blood loss, incidence of postoperative complications and length of hospital stay between the two groups (all P>0.05). The decrease of renal sGFR in the group A was significantly higher than group B at 3 months and 12 months after surgery [(23.1±3.6) vs (29.1±7.1) ml/min;(25.9±4.7) vs (30.7±7.2),both P<0.05]. Conclusion: Retroperitoneal laparoscopic selective renal artery branch occlusion and neon-sparing surgery for patients with ≥ T1b stage renal carcinoma is a safe and effective surgical method, which can well protect the renal function of patients in the early postoperative stage without increasing intraoperative blood loss and postoperative complications.

Comparison of Differential Functional Outcomes After Partial Nephrectomy Between Moderate and High Complex Renal Tumor Evaluated with Diethylenetriamine Pentaacetic Acid Scan: A Propensity Score Matched Analysis.

The aim of this study was to compare functional outcomes after partial nephrectomy (PN) between moderate and high complex renal tumors evaluated with a diethylenetriamine pentaacetic acid (DTPA) scan [moderate vs. high: RENAL nephrometry score (RNS) 7-9 vs. 10-12]. From January 2004 to December 2019, 471 patients with an RNS of 7-9 (moderate) and 164 patients with an RNS of 10-12 (high) who underwent PN were analyzed for renal function outcomes. The glomerular filtration rate (GFR)was measured using a DTPA scanand calculated the GFR using the Modification of Diet in Renal Disease (MDRD) formula, respectively. Trifecta/pentafecta outcome, recurrence-free survival, and overall survival were compared after propensity score matched analysis (PSMA). After PSMA, 156 cases in each group were matched without significant difference in the preoperative factor. At the postoperative first year, there was no significant difference in the trifecta (p=0.320), MDRD-based (p=0.729), or DTPA-based pentafecta achievement rate (p=0.964) between groups. At postoperative 5 years, DTPA-based total GFR (93.6% vs. 93.8%) and the operated kidney GFR preservation rate (89.9% vs. 81.7%) did not differ significantly (p>0.05). Kaplan-Meier survival analysis showed no significant differences in survival outcomes (p>0.05). Significant predictors of de novo chronic kidney disease (CKD) stage 3 or higher at the postoperative first year were age [hazard ratio (HR) 1.10, 95% confidence interval (CI) 1.03-1.17, p=0.005] and preoperative DTPA-based total GFR (HR 0.94, 95% CI 0.91-0.98, p=0.001). High complex tumors can be treated with PN without significant deterioration in renal function. The postoperative function of the operated kidney was preserved by up to 80% in the long term compared with the preoperative period. However, PN should be selectively performed with caution to avoid the occurrence of postoperative CKD.

Аналіз факторів дожиття до замісної ниркової терапії пацієнтів з хронічною хворобою нирок

Актуальність. Відношення між хронічною хворобою нирок (ХХН) і кардіоваскулярними захворюваннями (КВЗ) є важливими та комплексними і характеризуються наявністю численних несприятливих чинників порівняно з хворими з самостійними КВЗ. Мета дослідження: оцінити частоту факторів кардіоваскулярного ризику серцево­судинних ускладнень, нефрологічних факторів ризику та їх комбінацію у пацієнтів з ХХН IV–V ст., які дожили до етапу замісної ниркової терапії. Матеріали та методи. Ретроспективно проаналізовано медичну документацію (упродовж 2 років) 42 хворих (чоловіків — 12 (28,6 %), жінок — 30 (71,4 %)) на ХХН IV–V стадії, які на час проведення аналізу медичної документації не отримували замісну ниркову терапію. Усім хворим розраховували індекс маси тіла (ІМТ), визначали артеріальний тиск (АТ), частоту серцевих скорочень (ЧСС), оцінювали показники загального та біохімічного аналізу крові та сечі, визначали рівень залишкового діурезу. У всіх хворих обчислено швидкість клубочкової фільтрації (ШКФ) за формулою CKD­EPI. Статистична обробка матеріалів дослідження — пакет програм Statistica v.6.1 (Statsoft Inc., США). Результати. Середній вік пацієнтів становив 47,6 ± 11,6 року. Отримані дані засвідчили, що хворі на ХХН, які дожили до замісної ниркової терапії, мали добовий діурез понад 500 мл, ЧСС менше 90 уд/хв, рівень систолічного АТ у таких пацієнтів підтримувався медикаментозно на рівні менше 160 мм рт.ст., також характерною ознакою був рівень загального холестерину (ЗХС) крові ≥ 4,5 ммоль/л та ІМТ понад 25 кг/м2. Нами був виявлений прямий кореляційний зв’язок між рівнем ШКФ та рівнем ЗХС крові (r = 0,32, р = 0,04); між ШКФ та рівнем гемоглобіну крові (r = 0,39, р = 0,01) і прямий кореляційний зв’язок між ШКФ і кількістю залишкової сечі у обстежених хворих (r = 0,32, р = 0,04). Висновки. Найбільш вагомими чинниками доживання хворого на ХХН до замісної ниркової терапії є молодий вік (до 40 років), наявність залишкової сечі (добовий діурез понад 500 мл/добу), відсутність цукрового діабету. Велику роль відіграє контроль систолічного АТ &lt; 160 мм рт.ст. та анемії.

MP49-14 COMPARISON OF DIFFERENTIAL FUNCTIONAL OUTCOMES AFTER PARTIAL NEPHRECTOMY BETWEEN MODERATE AND HIGH COMPLEX RENAL TUMOR EVALUATED WITH DIETHYLENETRIAMINE PENTAACETIC ACID SCAN: A PROPENSITY SCORE MATCHED ANALYSIS

You have accessJournal of UrologyKidney Cancer: Localized: Surgical Therapy IV (MP49)1 Sep 2021MP49-14 COMPARISON OF DIFFERENTIAL FUNCTIONAL OUTCOMES AFTER PARTIAL NEPHRECTOMY BETWEEN MODERATE AND HIGH COMPLEX RENAL TUMOR EVALUATED WITH DIETHYLENETRIAMINE PENTAACETIC ACID SCAN: A PROPENSITY SCORE MATCHED ANALYSIS Hwanik Kim, Jin Noh, Jae Won Lee, Sang Hun Song, Hakju Kim, Jung Kwon Kim, Hakmin Lee, Sangchul Lee, Jong Jin Oh, Seong jin Jeong, Sung Kyu Hong, and Seok-Soo Byun Hwanik KimHwanik Kim More articles by this author , Jin NohJin Noh More articles by this author , Jae Won LeeJae Won Lee More articles by this author , Sang Hun SongSang Hun Song More articles by this author , Hakju KimHakju Kim More articles by this author , Jung Kwon KimJung Kwon Kim More articles by this author , Hakmin LeeHakmin Lee More articles by this author , Sangchul LeeSangchul Lee More articles by this author , Jong Jin OhJong Jin Oh More articles by this author , Seong jin JeongSeong jin Jeong More articles by this author , Sung Kyu HongSung Kyu Hong More articles by this author , and Seok-Soo ByunSeok-Soo Byun More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002075.14AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Renal function after partial nephrectomy (PN) depends on a complex of clinical conditions including preoperative parenchymal quality, postop parenchymal quantity, and the recovery of remaining nephrons from ischemic damages. However, the natural history and definitive predictors of long-term RF after PN in renal tumors with RENAL nephrometry score (RENAL) of 7-9 (moderate complex, M) or RENAL of 10-12 (high complex, H) remain unclear. Thus, the aim of the present study was to compare functional outcomes evaluated with diethylenetriamine pentaacetic acid (DTPA) scan and Modification of Diet in Renal Disease (MDRD) formula after PN between M and H renal tumors. METHODS: In 2004/01-2019/12, 471 patients with RNS 7-9 (M) and 164 with RNS 10-12 (H) who underwent PN were analyzed for renal function outcomes. Glomerular filtration rate (GFR) measured from DTPA scan, calculated GFR using Modification of Diet in Renal Disease (MDRD) formula, Trifecta/Pentafecta outcome, recurrence free survival (RFS), and overall survival (OS) were compared after propensity score matching analysis (PSMA). RESULTS: After PSMA, 156 cases in each group were matched without significant difference in preoperative factor. At postoperative (postop) 1st year, there was no significant difference in Trifecta (p=0.320), MDRD-based (p=0.729), or DTPA-based Pentafecta achievement rate (p=0.964) between groups. At postop 5 years, DTPA-based total GFR (93.6% vs. 93.8%) and operated kidney GFR preservation rate (89.9% vs. 81.7%) did not differ significantly (p>0.05). Kaplan-Meier survival analysis showed no significant differences in survival outcomes (p>0.05). Significant predictors of de novo chronic kidney disease (CKD) stage ≥3 at postop 1st year were age (Hazard ratio (HR): 1.10, 95% CI: 1.03-1.17, p=0.005) and preoperative DTPA-based total GFR (HR: 0.94, 95% CI: 0.91-0.98, p=0.001). CONCLUSIONS: High complex tumor can be treated with PN without significant renal function deterioration. Postoperative operated kidney’s function is preserved up to 80% in the long term. However, PN should be selectively performed with caution to avoid occurrence of postop CKD. Source of Funding: None © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e881-e881 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Hwanik Kim More articles by this author Jin Noh More articles by this author Jae Won Lee More articles by this author Sang Hun Song More articles by this author Hakju Kim More articles by this author Jung Kwon Kim More articles by this author Hakmin Lee More articles by this author Sangchul Lee More articles by this author Jong Jin Oh More articles by this author Seong jin Jeong More articles by this author Sung Kyu Hong More articles by this author Seok-Soo Byun More articles by this author Expand All Advertisement Loading ...

The correlation between kidney volume and measured glomerular filtration rate\xa0in an Asian ADPKD population: a prospective cohort study

BackgroundAutosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary kidney disorder that leads to end stage renal disease (ESRD). Cyst expansion in ADPKD is strongly associated with the decline in renal function. However, the correlation between total kidney volume (TKV) and glomerular filtration rate (GFR) at an early stage has not been well demonstrated. There is growing evidence that utilization of estimated GFR (eGFR) may induce misleading information in a population with near normal renal function. Therefore, a more accurate method is essential.MethodsA prospective cohort of ADPKD patients was conducted with clinical data and laboratory collection. Measured GFR (mGFR) was assessed by iohexol plasma clearance method using ultra performance liquid chromatography. eGFR was calculated using the CKD-EPI equation. Kidney volumes were evaluated using MRI imaging protocol.ResultsThirty two patients completed the study. The mean age was 56 years old. The mean initial mGFR was 83.8 mL/min/1.73m2. The mean change in mGFR per year was –2.99 mL/min/1.73m2/year. The mean initial height-adjusted TKV (htTKV) was 681.0 mL/m. The mean percentage change in htTKV per year (%ΔhtTKV/y) was 4.77 %/year. mGFR had a better association with clinical parameters than eGFR. Initial mGFR was significantly and inversely correlated with initial htTKV and age. The percentage change in mGFR per year was significantly and inversely correlated with the %ΔhtTKV/y and 24-hr urine albumin. The %ΔhtTKV/y was significantly correlated with initial htTKV.ConclusionsOur studies demonstrated that mGFR using iohexol is a more reliable and accurate method than eGFR for evaluating GFR changes in the early stages of ADPKD patients. There is a strong inverse correlation between kidney volume and mGFR in an Asian ADPKD population. The initial htTKV is a good predictor of kidney volume progression. The %ΔhtTKV/y is a good early surrogate marker for the decline in renal function. 24-hr urine albumin is also a good indicator for renal progression.