Renal Function In Peritoneal Dialysis Research Articles

The association between serum cystatin C and residual renal function in peritoneal dialysis patients.

This study evaluated the association between serum cystatin C and residual renal function (RRF) in peritoneal dialysis (PD) patients. The ability of cystatin C to predict RRF was assessed. Multivariate linear regression analysis was conducted to measure the impact of particular factors on serum cystatin C levels. The study included 141 PD patients. Serum creatinine and cystatin C were negatively correlated with RRF (p < 0.05). Receiver operating characteristic (ROC) curves showed that serum creatinine and cystatin C could both predict RRF status (p < 0.05), but serum cystatin C had a larger area AUC than creatinine (0.893 vs. 0.757, respectively), p < 0.001). Multiple linear regression analysis revealed that RRF Kt/V and Ccr were independent factors affecting serum cystatin C levels (p < 0.001). Serum cystatin C levels were closely associated with RRF in PD patients and could reliably predict RRF status. Serum cystatin C levels were determined by RRF, not by PD.

High-Salt Diet Accelerated the Decline of Residual Renal Function in Patients With Peritoneal Dialysis

Objective: This study aims to investigate the relationship between dietary salt intake and residual renal function in peritoneal dialysis (PD) patients.Methods: The daily salt intake of the patients was calculated based on a 3 day dietary record. Sixty-two patients were divided into three groups: 33 patients in the low salt intake group (salt intake <6.0 g/day), 17 in the medium salt intake group (salt intake 6.0 to <8.0 g/day), and 12 in the high salt intake group (salt intake ≥8.0 g/day). Regular follow-up was conducted every 3 months. Urine volume, peritoneal ultrafiltration volume, and other clinical indicators were recorded. Biochemical indexes were detected to evaluate the changes in residual renal function and peritoneal function during follow-up.Results: A positive correlation between dietary sodium intake and sodium excretion was found. During 12-month follow-up, a decrease of residual renal function showed a significant difference among the three groups (p = 0.041) (15.3 ± 27.5 vs. 12.5 ± 11.5 vs. 32.9 ± 18.4 L/W/1.73 m2 in the low-, medium-, and high salt intake groups, respectively). Consistently, a higher decline of residual renal function (adjusted β, 20.37; 95% CI, 2.83, 37.91) was found in participants with high salt intake (salt intake ≥8 g/day) compared with those in non-high salt intake.Conclusion: Our study showed that the sodium excretion by peritoneal dialysis was positively correlated with dietary sodium intake in PD patients. The high salt intake diet (salt intake ≥8 g/day) may lead to a faster decline of residual renal function in PD patients.

Soluble CD59 in peritoneal dialysis: a potential biomarker for peritoneal membrane function

IntroductionVarious studies have reported the importance of complement regulators in preventing mesothelial damage during peritoneal dialysis (PD). Its assessment, however, is limited in clinical practice due to the lack of easy access to the peritoneal membrane. Recently, a soluble form of the complement regulatory protein CD59 (sCD59) has been described. We therefore aimed to investigate the role of sCD59 in PD.MethodsPlasma sCD59 was measured in 48 PD patients, 41 hemodialysis patients, 15 non-dialysis patients with chronic kidney disease and 14 healthy controls by ELISA (Hycult; HK374-02). Additionally, sCD59 and sC5b-9 were assessed in the peritoneal dialysate.ResultssCD59 and sC5b-9 were detectable in the peritoneal dialysate of all patients, and marginally correlated (r = 0.27, P = 0.06). Plasma sCD59 levels were significantly higher in PD patients than in patients with chronic kidney disease and healthy controls, but did not differ from hemodialysis patients. During follow-up, 19% of PD patients developed peritoneal membrane failure and 27% of PD patients developed loss of residual renal function. In adjusted models, increased sCD59 levels in the dialysate (HR 3.44, 95% CI 1.04–11.40, P = 0.04) and in plasma (HR 1.08, 95% CI 1.01–1.17, P = 0.04) were independently associated with the occurrence of peritoneal membrane failure. Higher plasma levels of sCD59 were also associated with loss of residual renal function (HR 1.10, 95% CI 1.04–1.17, P < 0.001).ConclusionsOur study suggests that sCD59 has potential as a biomarker to predict peritoneal membrane function and loss of residual renal function in PD, thereby offering a tool to improve patient management.Graphic abstract

The Importance of Residual Renal Function in Peritoneal Dialysis

The Importance of Residual Renal Function in Peritoneal Dialysis

Red cell distribution width reflects the early stage residual renal function in peritoneal dialysis patients.

It has been verified that the red blood cell distribution width (RDW) is related to renal function. This study aimed to investigate the association of RDW with the residual renal function in peritoneal dialysis (PD) patients. The patients were categorized into three groups according to the quartiles of their baseline RDWs. The correlations between RDW and clinical parameters, dialysis adequacy, and residual renal function were analyzed. The clinical data, PD prescription and dialysis adequacy of 54 uremic patients on continuous ambulatory PD were collected. All the statistical analyses were performed using the Statistical Package for the Social Sciences program version 17.0. The baseline RDW of the patients was 13.56% ± 1.36%. No significant differences in the other indexes [hemoglobin, albumin, alkaline phosphatase, intact parathyroid hormone (iPTH), urea and creatinine] among the three groups were found. One month after beginning PD, the correlation between the RDW and the residual renal function has not been found in the multivariate regression model adjusted for the hemoglobin, albumin, and leukocyte. Three months after beginning the PD, a significant difference between Group 2 and Group 3 in iPTH was found. Multivariate regression analysis showed that the elevated RDW is associated with the declined residual glomerular filtration rate (heart rate = -0.587, 95% confidence interval -1.080 ~ -0.093) for the corresponding period after PD, adjusted for the hemoglobin, albumin, and leukocyte. This study showed that the RDW reflected the residual renal function in the corresponding period after PD in the PD patients.

Oral Bicarbonate Slows Decline of Residual Renal Function in Peritoneal Dialysis Patients

Background/Aims: Metabolic acidosis is a common consequence of end-stage renal disease (ESRD) which may result in a substantial adverse outcome. The effect of oral bicarbonate on the preservation of residual renal function (RRF) in peritoneal dialysis (PD) patients has been rarely reported. Methods: We randomly assigned 40 continuous ambulatory peritoneal dialysis (CAPD) patients to the oral bicarbonate group or placebo group at a 1: 1 ratio. All enrollments were followed for a duration of 104 weeks. We took residual creatinine clearance (CCr), a measure of residual renal function (RRF), as the primary outcome. Residual CCr was calculated as the average of urea and creatinine clearance from a 24-hour urine collection. Results: Thirteen patients in the placebo group and 15 patients in the treatment group completed the 104 weeks of follow-up with a comparable dropout rate (placebo group: 35% vs treatment group: 25%). Compared with the placebo group, serum bicarbonate in treatment group was significantly increased at each time point, and oral bicarbonate resulted in a slower declining rate of residual CCr (F=5.113, p=0.031). Baseline residual CCr at enrollment also had a significant effect on residual CCr (F=168.779, P<0.001). Charlson Comorbidity Index which was adopted to calculate a comorbidity score had no significant effect on residual CCr loss (F=0.168, P=0.685). Conclusion: Oral bicarbonate may have a RRF preserving effect in CAPD patients, and a normal to high level of serum bicarbonate (≥24mmol/L) may be appropriate for RRF preservation.

Interests of Residual Renal Function in Peritoneal Dialysis

Background: Decline of Residual renal function (RRF) is commonly observed in dialysis patients. RRF may play a significant role in the treatment adequacy and outcomes of dialysis patients. Several prospective observational and interventional studies have shown that the presence of RRF was associated with an improved outcome and a reduced mortality in dialysis patients. Preserving RRF is an old holistic dream that still remains to date a source of debate among the nephrologists. The aim of our study was to evaluate the impact of preservation of residual renal function in peritoneal dialysis (PD). Methods: The study was retrospective, descriptive and analytical including patients on peritoneal dialysis in the Nephrology Department of Sahloul Hospital in Sousse during the period from 1 December 2006 to 30 June 2014. We noted clinical and biological parameters for patients with and without RRF. The FRR was defined as a residual clearance upper than 1 ml/min. All statistical analysis was performed with SPSS statistical software version 20. For each parameter the mean ± deviation was calculated. The significance of effects was tested using analysis of variance (ANOVA). Values <0.05 were considered significant. Multiple regression analysis was performed in order to investigate the relationship between RRF and various independent variables (age, gender, blood pressure, and etiology of end stage renal disease). Results: During the study period, 48 patients were collected. RRF was found in 71% of patients with PD. Several benefits were demonstrated: better control of anemia (9.2 vs. 8.01 g/dl), better balance of uricemia (303 vs. 393 μmol/l) a better balance of phosphorus (1.4 vs. 1.8 mmol/l) and a lower risk of peritonitis (absence of peritonitis in 71 vs. 30%). Conclusion: The FRR is an important parameter that should be taken into account in our medical care in dialysis. Its protection should therefore be considered and it responds to many factors.

The Impact of Fluid Overload and Variation on Residual Renal Function in Peritoneal Dialysis Patient.

BackgroundThe effect of fluid overload and variation on residual renal function (RRF) in peritoneal dialysis (PD) patients is controversial.MethodsRetrospective cohort study was designed. One-hundred and ninety PD patients with measured glomerular filtration rate (mGFR) ≧ 3ml/min/1.73m2 were recruit. Fluid status of every participant was assessed by bioelectrical impedance analysis (BIA) every 3 months for 1 year. The cohort was divided into three hydration groups, namely persistent overhydration (PO) group, intermittent overhydration (IO) group and normal hydration (NH) group. Additionally, participants were also divided into high or low fluid variation groups. The decline rate of RRF and the event of anuria were followed up for 1 year. The association of fluid overload with RRF loss was evaluated by Cox proportional hazard models adjusted for confounders.ResultsThirty-six (18.9%) patients developed anuria. The decline rate of mGFR in both PO and IO groups were significantly faster than that of NH group (PO vs NH: -0.2 vs -0.1 ml/min/1.73m2/month, p < 0.01; IO vs NH: -0.2 vs -0.1 ml/min/1.73m2/month, p < 0.01). Kaplan-Meier analysis showed poorer RRF outcome in both PO and IO groups compared with that of NH group (PO vs NH: p < 0.001; IO vs NH: p = 0.006). Patients with high fluid variation had worse RRF survival than those with low fluid variation (p = 0.04). Adjusted Cox regression models indicated the hazard ratio of RRF loss in PO group was 8.90-folds higher (95% confidence interval 3.07–31.89) than that in NH group.ConclusionsThese findings suggested fluid overload was independently associated with the decline of RRF in PD patients.

A Pilot Study Examining the Effects of Tolvaptan on Residual Renal Function in Peritoneal Dialysis for Diabetics.

For patients with end-stage renal disease (ESRD), peritoneal dialysis (PD) serves as a possible renal replacement therapy. However, most PD patients, particularly those with ESRD and diabetes mellitus, reportedly discontinue PD early, resulting in shorter survival periods and poorer prognosis because of overhydration. Recently, the vasopressin-2 receptor antagonist tolvaptan was approved for volume control in patients with heart failure. The present study aimed to identify the effects of tolvaptan in diabetic PD patients. In this pilot study, the tolvaptan group (n = 12) were treated with 15 mg/day of tolvaptan 2 weeks after PD initiation and were prospectively analyzed for 1 year, and patients in the control group (n = 12) did not receive tolvaptan and were retrospectively analyzed for 1 year. In addition to the biochemical tests, echocardiograms, serum atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels, peritoneal Kt/V, and creatinine clearance (CCr) were examined at baseline and at 6 and 12 months after PD initiation. In the control group, the urine volume, renal Kt/V, and renal CCr levels consistently decreased; however, these parameters were stably maintained during the study period in the tolvaptan group. Atrial natriuretic peptide, CRP levels and the left ventricular mass index of the tolvaptan-treated group were significantly lower than those in the control group, whereas total protein and albumin levels were significantly higher at 6 and 12 months in the tolvaptan group. There were no obvious adverse effects. These data suggest that tolvaptan may preserve residual renal function and improve volume control in PD patients with diabetes mellitus.

Japanese society for dialysis therapy clinical guideline for "hemodialysis initiation for maintenance hemodialysis".

Yuzo Watanabe, Kunihiro Yamagata, Shinichi Nishi, Hideki Hirakata, Norio Hanafusa, Chie Saito, Motoshi Hattori, Noritomo Itami, Yasuhiro Komatsu, Yoshindo Kawaguchi, Kazuhiko Tsuruya, Yoshiharu Tsubakihara, Kazuyuki Suzuki, Ken Sakai, Hideki Kawanishi, Daijo Inaguma, Hiroyasu Yamamoto, Yoshiaki Takemoto, Noriko Mori, Kazuyoshi Okada, Hiroshi Hataya, Takashi Akiba, Kunitoshi Iseki, Tadashi Tomo, Ikuto Masakane, Tadao Akizawa, and Jun Minakuchi, for “Hemodialysis Initiation for Maintenance Hemodialysis” Guideline Working Group, Japanese Society for Dialysis Therapy

Fluid overload and residual renal function in peritoneal dialysis: the proof of the pudding is in the eating

McCafferty and colleagues report on a retrospective analysis in peritoneal dialysis patients in whom fluid status was assessed by multifrequency bioimpedance. During 12 months of follow-up, overhydration, as identified by an increased ratio of extracellular over total body water, was not associated with better preservation of residual renal function (RRF). These findings suggest that running patients 'wet' might not contribute to better preservation of RRF in peritoneal dialysis.

Residual renal function in peritoneal dialysis with failed allograft and minimum immunosuppression

Immunosuppression (IS) is often withdrawn in patients with end stage renal disease secondary to a failed renal allograft, and this can lead to an accelerated loss of residual renal function (RRF). As maintenance of RRF appears to provide a survival benefit to peritoneal dialysis (PD) patients, it is not clear whether this benefit of maintaining RRF in failed allograft patients returning to PD outweigh the risks of maintaining IS. A 49 year-old Caucasian male developed progressive allograft failure nine years after living-donor renal transplantation. Hemodialysis was initiated via tunneled dialysis catheter (TDC) and IS was gradually withdrawn. Two weeks after IS withdrawal he developed a febrile illness, which necessitate removal of the TDC and conversion to PD. He was maintained on small dose of tacrolimus (1 mg/d) and prednisone (5 mg/d). Currently (1 year later) he is doing exceedingly well on cycler-assisted PD. Residual urine output ranges between 600-1200 mL/d. Total weekly Kt/V achieved 1.82. RRF remained well preserved in this patient with failed renal allograft with minimal immunosuppressive therapy. This strategy will need further study in well-defined cohorts of PD patients with failed allografts and residual RRF to determine efficacy and safety.

Definition and Risk Factors of Rapidly Declining Residual Renal Function in Peritoneal Dialysis: An Observational Study

Background: It is critical to preserve residual renal function (RRF) in peritoneal dialysis (PD), as RRF is associated with lower morbidity and mortality. There is no uniform definition of RRF, and rapidly declining RRF has rarely been studied and predominately limited to single factor analysis and not corrected for lead-time bias. Methods: An observational study in 71 incident PD patients. RRF was defined as urine output (UO) ≥500 ml/day and renal glomerular filtration rate (rGFR) ≥2 ml/min/1.73 m², rapid declining RRF as UO <500 ml/day and rGFR <2 ml/min/1.73 m² occurring within 6 months which were separately evaluated. Independent risk factors associated with rapid RRF decline were identified while correcting for lead-time bias. Results: RRF declined rapidly by both definitions in 65% patients 2.5 years after PD start. Both definitions of RRF decline were consistent in 96%. Nephrotoxic drugs, renal transplant failure and absent angiotensin-converting enzyme inhibitors (ACEI) or angiotensin II receptor blockers (ARB) were independent risk factors associated with rapidly declining RRF defined both by definitions, intravascular radiocontrast additionally for UO decline. Conclusions: Most PD patients demonstrated rapid RRF decline, independent of its definition. Both definitions are highly consistent and interchangeable. Nephrotoxic drugs and radiocontrast were identified as risk factors of acute, absent ACEI or ARB, and renal transplant failure of chronic renal injury.

Relation of ankle‐brachial index to the rate of decline of residual renal function in peritoneal dialysis patients

The aim of this study was to determine whether ankle-brachial index (ABI) predicts the rate of decline of residual renal function (RRF) in peritoneal dialysis (PD) patients. Previous studies demonstrated the importance of loss of RRF in predicting all-cause risk and cardiovascular mortality in PD patients. It is also known that patients with a low ABI value have a greater risk for deteriorating renal function in the general population. The relationship between ABI and the declining rate of RRF in PD patients with an additional dialysis-specific risk factor is uncertain. Seventy-four PD patients with RRF of more than 1 mL/min per 1.73 m(2) were analyzed. ABI was used as the surrogate measure of pre-existing cardiovascular disease and atherosclerosis burden to further determine the outcome of RRF in this study. The slope of decline of RRF was used to determine the outcome. Based on the multivariate analysis, only ABI (P < 0.001), diabetes (P = 0.02) and baseline RRF (P = 0.009) independently predicted a faster decline in RRF. A stepwise multiple linear regression analysis demonstrated that ABI was an independent predictor for the slope of decline of RRF (P < 0.001). A low ABI is an independent predictor of not only the known atherosclerotic events, but also of the rate of decline of RRF over time in PD patients.

Rationale and design of the balANZ trial: A randomised controlled trial of low GDP, neutral pH versus standard peritoneal dialysis solution for the preservation of residual renal function

BackgroundThe main hypothesis of this study is that neutral pH, low glucose degradation product (GDP) peritoneal dialysis (PD) fluid better preserves residual renal function in PD patients over time compared with conventional dialysate.Methods/DesignInclusion criteria are adult PD patients (CAPD or APD) aged 18-81 years whose first dialysis was within 90 days prior to or following enrolment and who have a residual GFR ≥ 5 ml/min/1.73 m2, a urine output ≥ 400 ml/day and an ability to understand the nature and requirements of this trial. Pregnant or lactating patients or individuals with an active infection at the time of enrolment, a contra-indication to PD or participation in any other clinical trial where an intervention is designed to moderate rate of change of residual renal function are excluded. Patients will be randomized 1:1 to receive either neutral pH, low GDP dialysis solution (Balance®) or conventional dialysis solution (Stay.safe®) for a period of 2 years. During this 2 year study period, urinary urea and clearance measurements will be performed at 0, 3, 6, 9, 12, 18 and 24 months. The primary outcome measure will be the slope of residual renal function decline, adjusted for centre and presence of diabetic nephropathy. Secondary outcome measures will include time from initiation of peritoneal dialysis to anuria, peritoneal small solute clearance, peritoneal transport status, peritoneal ultrafiltration, technique survival, patient survival, peritonitis rates and adverse events. A total of 185 patients has been recruited into the trial.DiscussionThis investigator-initiated study has been designed to provide evidence to help nephrologists determine the optimal dialysis solution for preserving residual renal function in PD patients.Trial RegistrationAustralian New Zealand Clinical Trials Registry Number: ACTRN12606000044527

Residual Renal Function in Peritoneal Dialysis after Renal Transplant Failure

out of the question to perform any randomized studies to evaluate the effect of declining RRF on endothelial function. In conclusion, this study showed that the decline in RRF in incident CAPD patients is associated with worsened endothelial dysfunction, while a stable RRF seems not to affect endothelial function significantly. This study not only provided new understanding of the association between RRF and cardiovascular disease in dialysis patients, but also highlighted the justification of protecting RRF in this population.

Benefits of preserving residual renal function in peritoneal dialysis

Residual renal function (RRF) is of paramount importance in patients with end-stage renal disease, with benefits that go beyond contributing to achievement of adequacy targets. Several studies have found that RRF rather than overall adequacy (as estimated from total small solute removal rates) is an essential marker of patient and, to a lesser extent, technique survival during chronic peritoneal dialysis (PD) therapy. In addition, RRF is associated with a reduction in blood pressure and left ventricular hypertrophy, increased sodium removal and improved fluid status, lower serum beta(2)-microglobulin, phosphate and uric acid levels, higher serum hemoglobin and bicarbonate levels, better nutritional status, a more favorable lipid profile, decreased circulating inflammatory markers, and lower risk for peritonitis in PD. As compared with conventional hemodialysis, PD is associated with a slower decrease in RRF. This highlights the usefulness of strategies oriented to preserve both RRF and the long-term viability of the peritoneal membrane. Several factors contributing to the loss of RRF have been identified and should be avoided. Renoprotective drugs and new glucose-sparing, more biocompatible PD regimes may prove useful tools to preserve RRF and peritoneal membrane function in the near future.

Renal toxicity mediated by glucose degradation products in a rat model of advanced renal failure

In peritoneal dialysis (PD) residual renal function contributes to improved patient survival and quality of life. Glucose degradation products (GDP) generated by heat sterilization of PD fluids do not only impair the peritoneal membrane, but also appear in the systemic circulation with the potential for organ toxicity. Here we show that in a rat model of advanced renal failure, GDP affect the structure and function of the remnant kidney. Sprague-Dawley rats were randomly assigned to a two stage subtotal nephrectomy (SNX) or sham operation and were left untreated for 3 weeks. The SNX + GDP group continuously received chemically defined GDP intravenously for 4 weeks; the SNX and the sham-operated rats remained without GDP. The complete follow-up for all groups was 7 weeks postoperatively. We analysed renal damage using urinary albumin excretion as well as a semiquantitative score for glomerulosclerosis and tubulointerstitial damage, as well as for immunohistochemical analyses. The SNX + GDP rats developed significantly more albuminuria and showed a significantly higher score of glomerulosclerosis index (GSI) and tubulointerstitial damage index (TII) as compared to SNX or control rats. In the SNX + GDP group the expression of carboxymethyllysine and methylglyoxal was significantly higher in the tubulointerstitium and the glomeruli compared to the SNX rats. Caspase 3 staining and TUNEL assay were more pronounced in the tubulointerstitium and the glomeruli of the SNX + GDP group. In SNX + GDP animals, the expression of the slit diaphragm protein nephrin, was significantly lower compared to SNX or control animals. In summary, our data suggests that GDP can significantly advance chronic kidney disease and argues that PD solutions containing high GDP might deteriorate residual renal function in PD.

3,4-Dideoxyglucosone-3-ene Induces Apoptosis in Renal Tubular Epithelial Cells

Diabetes complications are caused by hyperglycemia. Hyperglycemia results in increased concentrations of glucose degradation products. The study of peritoneal dialysis solution biocompatibility has highlighted the adverse effects of glucose degradation products. Recently, 3,4-dideoxyglucosone-3-ene (3,4-DGE) has been identified as the most toxic glucose degradation product in peritoneal dialysis fluids. Its role in renal pathophysiology has not been addressed. 3,4-DGE induces apoptosis in murine renal tubular epithelial cells in a dose- and time-dependent manner. Peak apoptosis is observed after 72 h of culture. The lethal concentration range is 25-50 micromol/l. 3,4-DGE results in Bax oligomerization, release of cytochrome c from mitochondria, activation of caspases-9 and -3, and Bid proteolysis. Apoptosis induced by 3,4-DGE is caspase dependent and could be prevented by the broad-spectrum caspase inhibitor zVAD-fmk (Z-Val-Ala-DL-Asp-fluoromethylketone) and by specific inhibitors of caspases-2, -8, and -9. However, caspase inhibition did not prevent eventual cell death. In contrast, antagonism of Bax by a Ku-70-derived peptide or antisense oligonucleotides prevented both apoptosis and cell death. In conclusion, 3,4-DGE promotes apoptosis of cultured renal parenchymal cells by a Bax- and caspase-dependent mechanism. A role for 3,4-DGE in diabetes complications in the kidney and in the modulation of residual renal function in peritoneal dialysis should be further explored.

A reevaluation of empiric therapy for peritoneal dialysis-related peritonitis

A reevaluation of empiric therapy for peritoneal dialysis-related peritonitis