Residual Kidney Function In Patients Research Articles

Redefining the concept of residual renal function with kidney sodium MRI: a pilot study.

The concept of residual kidney function (RKF) is exclusively based upon urine volume and small solute clearance, making RKF challenging to assess in clinical practice. The aim of this study was to test the technical feasibility of obtaining useable 23Na-MRI kidney images in hemodialysis (HD) participants. We conducted an exploratory prospective study to quantify the cortico-medullary sodium gradient in healthy and HD participants. Participants fasted for eight hours prior to their study visit. Urine samples were collected to measure urinary osmolarity, before MRI. Proton and sodium pictures were merged; ROIs were delineated for the medulla and cortex when feasible. In cases where cortex could not be identified, we considered the cortico to medulla gradient (CMG) to be no longer present, resulting in a medulla-to-cortex ratio of 1. 17 healthy volunteers and 21 HD participants. Median (IQR) fasting medulla to cortex ratio was significantly higher 1.56 [1.5-1.61] in healthy volunteers compared to HD patients 1.22 [1.13-1.3], p<0.0001. Medulla to cortex ratio and median urinary osmolarity were correlated (r=0.87, p<0.0001) in the whole population. We found a significant association between HD vintage and medulla to cortex ratio whereas we did not find any association with urine volume. Sodium signal intensity distribution within healthy kidney describes two different peaks- relating to well defined cortex and medulla; whereas HD participants displays only a single peak indicative of the markedly lower sodium concentration. This study is only an exploratory study with a modest number of patients. the application of kidney sodium MRI to the study of RKF in patients receiving maintenance HD is practical and provides a previously unavailable ability to interrogate the function of remnant tubular function.

Incremental Versus Conventional Hemodialysis for Preservation of Residual Kidney Function in Patients on Regular Hemodialysis

Incremental hemodialysis has many potential benefits to patients clinicians and health systems.The aim of this work was to evaluate incremental hemodialysis twice/week compared with conventional dialysis thrice/week for preservation of the residual kidney function among patients initiating regular hemodialysis.Study design Prospective, comparative study.Setting Nephrology department Military Hospitals AL-maadi kobry AL-koba and air force military hospital.Subjects We assigned 40 patients with chronic kidney disease stage V D who early started hemodialysis into2 groups Group1:20 patients underwent incremental hemodialysis twice/week and Group2:20 patients underwent conventional hemodialysis thrice/week.Methods: All patients followed for laboratory findings of complete blood picture creatinine urea calcium albumin phosphorus parathyroid hormone alkaline phosphatase glomerular filtration rate. Also Kt/v at start and every month was done.Clinical outcome measures included mortality cardiovascular outcome hospital admission and dialysis complications.Results: In the studied population,the mean age was45.95±2.97 years.Regarding sex 60% were males and 40% were females. Regarding outcome data20%of patients had hypotension15%had hospital admission,while nobody suffered mortality.Comparative study betwee the 2 groups revealed; significant decrease in hypotension incidence in incremental group 40%compared to conventional group 10% p=0.03.Conclusion: To conclude, our study examines associations between HD treatment frequency and patient survival. In agreement with recent literature,30,31 our findings suggest that in an incident HD population, certain selected patients with adequate RKF, adequate control of interdialytic weight gain,and low or moderate comorbid disease burden CCI <5 an incremental HD approach

Evaluation of Residual Kidney Function during Once-Weekly Incremental Hemodialysis

Background: The initial once-weekly administration of incremental hemodialysis to patients with residual kidney function (RKF) has recently attracted considerable interest. Methods: The aim of our study was to assess the performance of a series of different methods in measuring serum urea nitrogen and serum Cr (sCr) RKF in patients on once-weekly hemodialysis (1WHD). Evaluations were carried out by means of 24-h predialysis urine collection (Kr-24H) or 6-day inter-dialysis collection (Kr-IDI) and estimation of glomerular filtration rate based on (KrSUN + KrsCr)/2 for the purpose of identifying a simple reference calculation to be used in assessing RKF in patients on 1WHD dialysis. Ninety-five urine samples were collected from 12 1WHD patients. A solute solver urea and Cr kinetic modeling program was used to calculate residual urea and Cr clearances. Mann-Whitney U test, Pearson’s correlation coefficient (R), and linear determination coefficient (R²) were used for statistical analysis. Results: 1WHD patients displayed a mean KrSUN-IDI of 4.5 ± 1.2 mL/min, while KrSUN-24H corresponded to 4.1 ± 0.9 mL/min, mean KrsCr-IDI to 9.1 ± 4.0 mL/min, and KrsCr 24H to 8.9 ± 4.2 mL/min, with a high regression between IDI and 24-h clearances (for IDI had R² = 0.9149 and for 24H had R² = 0.9595). A good correlation was also observed between KrSUN-24H and (KrSUN + KrsCR/2) (R² = 0.7466, p < 0.01. Discussion: Urine collection over a 24-h predialysis period yielded similar results for both KrSUN and KrsCr compared to collection over a longer interdialytic interval (KrSUN + KrsCr)/2 could be applied to reliably assess RKF in patients on 1WHD. Conclusion: The parameters evaluated are suitable for use as a routine daily method indicating the commencement and continued use of the 1WHD Incremental Program.

Serum Uric Acid, Mortality, and Decline of Residual Kidney Function in Patients Undergoing Chronic Peritoneal Dialysis

Serum Uric Acid, Mortality, and Decline of Residual Kidney Function in Patients Undergoing Chronic Peritoneal Dialysis

Lower Serum Albumin Level Is Associated With an Increased Risk for Loss of Residual Kidney Function in Patients Receiving Peritoneal Dialysis.

Preserving residual kidney function (RKF) is important in the management of patients on peritoneal dialysis. However, few studies have examined the association between serum albumin level and the risk of RKF loss. We prospectively recruited 104 patients who began peritoneal dialysis treatment at our hospital between 2006 and 2016. The primary outcome was complete RKF loss, defined as urine volume < 100 mL/day. Serum albumin level at baseline was the main exposure. During a median observation period of 24 months, 33 patients developed RKF loss. A Cox proportional hazards model showed that hypoalbuminemia was associated with an increased risk of RKF, even after adjustments for potential confounding factors. Multivariable-adjusted linear regression analysis also showed that hypoalbuminemia was associated with greater rates of decline in 24-h urine volume and in renal Kt/V urea. Our findings suggest that hypoalbuminemia is associated with an increased risk of RKF loss in patients with peritoneal dialysis.

The evaluation of residual kidney function in patients with ckd vd and approaches of its preservation

The work is a literature review. Residual kidney function (RKF) is one of the crucial indicators of mortality and quality of life in patients with chronic kidney disease. Residual renal function provides better control of hydration, blood pressure, clearance of substances with low and middleweight, anemia, Ca/P metabolism, chronic inflammation. However, approaches to preservation of RKF in dialysis patients have been studied not enough, the importance of RKF preservation is underlined. The wide range of predictors of RKF loss are presented in the article, approaches to measurement of RKF, the relationship between level and presence of RKF with survival and mortality of patients with CKD 5D were analyzed. The possibility of RKF preservation and extension using different approaches by correction of dialysis prescription were estimated. There is no standardized method for applying incremental hemodialysis in practice. Onceto twice-weekly hemodialysis regimens are often used randomly, without knowing the benefit for current patient or how to escalate the dialysis dose if RKF declines over time. It is important to change the HD/HDF prescription according to the range of RRF using objective data.

Measurement and Estimation of Residual Kidney Function in Patients on Dialysis.

Residual kidney function (RKF) in patients on dialysis is strongly associated with survival and better quality of life. Assessment of kidney function underlies the management of patients with chronic kidney disease before dialysis initiation. However, methods to assess RKF after dialysis initiation are just now being refined. In this review, we discuss the definition of RKF and methods for measurement and estimation of RKF, highlighting the unique aspects of dialysis that impact these assessments.

Plasma Levels of Middle Molecules to Estimate Residual Kidney Function in Haemodialysis without Urine Collection.

BackgroundResidual Kidney Function (RKF) is associated with survival benefits in haemodialysis (HD) but is difficult to measure without urine collection. Middle molecules such as Cystatin C and β2-microglobulin accumulate in renal disease and plasma levels have been used to estimate kidney function early in this condition. We investigated their use to estimate RKF in patients on HD.DesignCystatin C, β2-microglobulin, urea and creatinine levels were studied in patients on incremental high-flux HD or hemodiafiltration(HDF). Over sequential HD sessions, blood was sampled pre- and post-session 1 and pre-session 2, for estimation of these parameters. Urine was collected during the whole interdialytic interval, for estimation of residual GFR (GFRResidual = mean of urea and creatinine clearance). The relationships of plasma Cystatin C and β2-microglobulin levels to GFRResidual and urea clearance were determined.ResultsOf the 341 patients studied, 64% had urine output>100ml/day, 32.6% were on high-flux HD and 67.4% on HDF. Parameters most closely correlated with GFRResidual were 1/β2-micoglobulin (r2 0.67) and 1/Cystatin C (r2 0.50). Both these relationships were weaker at low GFRResidual. The best regression model for GFRResidual, explaining 67% of the variation, was: GFRResidual=160.3⋅(1β2m)−4.2 Where β2m is the pre-dialysis β2 microglobulin concentration (mg/L). This model was validated in a separate cohort of 50 patients using Bland-Altman analysis. Areas under the curve in Receiver Operating Characteristic analysis aimed at identifying subjects with urea clearance≥2ml/min/1.73m2 was 0.91 for β2-microglobulin and 0.86 for Cystatin C. A plasma β2-microglobulin cut-off of ≤19.2mg/L allowed identification of patients with urea clearance ≥2ml/min/1.73m2 with 90% specificity and 65% sensitivity.ConclusionPlasma pre-dialysis β2-microglobulin levels can provide estimates of RKF which may have clinical utility and appear superior to cystatin C. Use of cut-off levels to identify patients with RKF may provide a simple way to individualise dialysis dose based on RKF.

Compared Decline of Residual Kidney Function in Patients Treated with Automated Peritoneal Dialysis and Continuous Ambulatory Peritoneal Dialysis: A Multicenter Study

Background: There is controversy concerning the compared rates of decline of residual kidney function (RKF) in patients treated with continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis (APD). Objectives and Method: Following an observational, multicenter design, we studied 493 patients initiating peritoneal dialysis (PD) in four different Spanish units. We explored the effect of the PD modality on the rate of decline of RKF and the probability of anuria during follow-up. We applied logistic regression for intention-to-treat analyses, and linear mixed models to explore time-dependent variables, excluding those affected by indication bias. Main Results: Patients started on APD were younger and less comorbid than those initiated on CAPD. Baseline RKF was similar in both groups (p = 0.50). Eighty-seven patients changed their PD modality during follow-up. The following variables predicted a faster decline of RKF: higher (rate of decline) or lower (anuria) baseline RKF, younger age, proteinuria, nonprimary PD, use of PD solutions rich in glucose degradation products, higher blood pressure, and suffering peritonitis or cardiovascular events during follow-up. Overall, APD was not associated with a fast decline of RKF, but stratified analysis disclosed that patients with lower baseline RKF had an increased risk for this outcome when treated with this technique (HR: 2.26, 95% CI: 1.09-4.82, p = 0.023). Moreover, the probability of anuria during follow-up was overtly higher in APD patients (HR: 3.22, 95% CI: 1.25-6.69, p = 0.002). Conclusions: Starting PD patients directly on APD is associated with a faster decline of RKF and a higher risk of developing anuria than doing so on CAPD. This detrimental effect is more marked in patients initiating PD with lower levels of RKF.

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers for preserving residual kidney function in peritoneal dialysis patients.

Angiotensin-converting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) are widely used in peritoneal dialysis (PD) patients, yet controversy exists about their impact on residual kidney function. This review aimed to evaluate the benefits and harms of ACEis and ARBs for preserving residual kidney function in PD patients. The Cochrane Renal Group's specialised register, Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE (OvidSP interface), Chinese Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI) and other resources were searched by applying a prespecified comprehensive search strategy. Date of last search: 01 May 2014. Randomised controlled trials (RCTs) and quasi-RCTs comparing ACEis or ARBs with placebo, other antihypertensive drugs or each other in PD patients were included. Screening, selection, data extraction and quality assessments for each retrieved article were carried out by two authors using standardised forms. Authors were contacted when published data were incomplete. Statistical analyses were performed using the random effects model and results expressed as risk ratio (RR) with 95% confidence intervals (CI). Heterogeneity among studies was explored using the Cochran Q statistic and the I² test, subgroup analyses and random effects meta-regression. Six open-label studies (257 patients) were identified. One study compared ACEi with other antihypertensive drugs, three compared ARBs with other antihypertensive drugs, and two studies compared an ARB with an ACEi. Long-term use (≥ 12 months) of an ARB showed significantly benefit of preserving residual kidney function in continuous ambulatory PD (CAPD) patients (MD 1.11 mL/min/1.73 m², 95% CI 0.38 to 1.83), although there was no significant benefit when an ARB were used short-term (≤ six months). One study showed that compared with other antihypertensive drugs, long-term use (12 months) of the ACEi ramipril showed a significant reduction in the decline of residual kidney function in patients on CAPD (MD -0.93 mL/min/1.73m², 95% CI -0.75 to -0.11), and delayed the progression to complete anuria (RR 0.64, 95% CI 0.41 to 0.99). There was no significant difference in serum potassium, urinary protein excretion, Kt/V, weekly creatinine clearance and blood pressure for ARBs versus other antihypertensive drugs. Compared with other antihypertensive drugs, ramipril showed no difference in mortality and cardiovascular events. Compared with an ACEi, ARBs did not show any difference in residual kidney function.The selection bias assessment was low in four studies and unclear in two. Five studies were open-label; however the primary outcome (residual kidney function) was obtained objectively from laboratory tests, and were not likely to be influenced by the lack of blinding. Reporting bias was unclear in all six studies. Compared with other antihypertensive drugs, long-term use (≥ 12 months) of ACEis or ARBs showed additional benefits of preserving residual kidney function in CAPD patients. There was no significant difference on residual kidney function preservation between ARBs and ACEis. However, limited by the small number of RCTs enrolling small number of participants, there is currently insufficient evidence to support the use of an ACEi or an ARB as first line antihypertensive therapy in PD patients.

The importance of residual renal function for patients on dialysis

It is the goal of every practitioner involved in the care of dialysis patients to maximize survival and quality of life. The last two decades have seen a plethora of investigations that have sought to determine how this goal can be achieved. The bulk of the studies have, unfortunately, concentrated on small solute clearance and outcome (measured principally as mortality). The HEMO [1] and ADEMEX [2] studies suggested that this is not a fruitful avenue of investigation. However, the residual kidney function in patients on dialysis, particularly in those on peritoneal dialysis (PD), has proven to be a consistent and powerful predictor of mortality. We will review the evidence supporting the importance of residual renal function (RRF) on outcome, propose some explanations as to why this relationship exists, and suggest ways to prolong the renal function in dialysis patients.