Assessment Of Dialysis Adequacy Research Articles

Utilization of the dialysate to characterize dialysis adequacy by using microwave urea biosensor based on complementary split-ring resonator (CSRR)

The aim of this study is going to develop a monitoring approach for measuring blood urea concentration. This method uses microwave technology and complementary split-ring resonator (CSRR) to assess dialysis adequacy. The robust electric field near CSRR sides produces a high-sensitivity surface to a change in the nearby urea level. The proposed biosensor detection range spans from 1 to 100 mg/dL by modifying resonance frequency and peak attenuation. The biosensor was developed to operate at the main resonance frequency of 2.4 GHz, but all harmonics within the frequency range of 1–10 GHz were analyzed. A container incorporates the dialysate as the material being tested on the top of the sensor. Accurate measurement of blood urea variations using spent dialysate compared to the blood-based method has benefits due primarily to the lack of repetitive blood sampling. The innovative biosensor offers a non-invasive and convenient method to accurately evaluate the quantitative urea concentration in spent dialysate without the necessity of disposable chemicals. The biosensor has been designed to possess noteworthy attributes such as detecting minuscule concentration variations, low-cost fabrication, compact size, high sensitivity, and its ability to provide real-time results. By merging these features, the sensor demonstrates remarkable potential for non-invasively monitoring blood urea levels while seamlessly integrating with other dialysis devices. The initiative purpose of this study is going to offer renal patients methods for assessing dialysis adequacy with minimal impact on human health.

#4797 ASSOCIATION BETWEEN BLOOD PRESSURE AND SALT CONSUMPTION WITH FLUID STATUS USING BIOIMPEDANCE SPECTROSCOPY IN PERITONEAL DIALYSIS PATIENTS

Abstract Background and Aims Control of extracellular volume in peritoneal dialysis (PD) patients requires both removal of sodium and water. Hypervolemia occurs more frequently in PD patients and is associated with greater morbidity and mortality. Dietary salt restriction (Na+ < 2g) is recommended in all PD patients. Most patients do not comply with this recommendation (prevalence difficult to assess). Bioimpedance spectroscopy (BIS) devices can help assess volume overload in patients receiving maintenance PD. The aim of our study was to determine the association between fluid status as measured using BIS to BP and salt consumption in continuous ambulatory peritoneal dialysis (CAPD) patients. Method We performed a retrospective, longitudinal study, that included 60 PD patients followed at our unit. Demographic and clinical characteristics, such as age, gender, chronic kidney disease (CKD) etiology, time on PD program, dialytic efficacy (Kt/V), peritoneal equilibration test results, BIS results and episodes of peritonitis were registered from our unit database. We measured total sodium removal and estimated daily sodium intake using dietary recall for one day, during the assessment of dialysis adequacy. Based on a 2017 study of 87 patients on PD that sought a correlation between effective daily sodium intake (memory recollection) and urinary + peritoneal sodium sieving. It allowed, through logistic regression, the creation of equations for patients with and without renal residual function (RRF) (Pearson's 0.6). Statistical analyses were performed using SPSS statistics version 23.0. The statistical hypothesis tests with p-value <0.05 were considered significant. Results Sixty patients (male: 60%) with a mean age of 55,9 ± 9 years were selected. Mean time on dialysis was 24,8 months ± 11,9 (min. 2, max. 63). The most common etiology of CKD was glomerular diseases (n = 16, 26.7%), followed by uncertain etiology (n = 11, 18.3%) and diabetic kidney disease (n = 9, 15%). In total, 71,7% of patients were on continuous ambulatory peritoneal dialysis (CAPD). Mean Kt/V was 2,2 ± 0,6 and the majority of patients were high-average transporters. Previous comorbidities were arterial hypertension (n = 60, 100%), diabetes (n = 16, 26,7%), heart failure (n = 13, 21,7%), body mass index >30 kg/m2 (n = 22, 36,7%) and dyslipidemia (n = 40, 66,7%). According to European Society of Cardiology we define three stages of hypertension: stage 1 (140–159/90–99 mmHg) with 15 patients (25%), stage 2 (160–179/100–109 mmHg) with 14 patients (23,3%) and stage 3 (≥180/≥110 mmHg) with 4 patients (6,7%). In total, we have 27 patients (45%) with hypertension under control. A statistically significant positive correlation was found between a status of overhydration (≥2liters) with salt consumption (Na+ >2g) (p = 0,01) and also of hypertension stages 2 and 3 (p = 0,03). Conclusion In PD patients, BIS is a reliable method for evaluating volume status. We found that stable CAPD patients with uncontrolled BP had higher overhydration and salt consumption compared to patients whose BP was controlled. Control of hypervolemia and blood pressure is associated with better cardiac condition. Thus, it is important to encourage patients on peritoneal dialysis to significantly restrict salt intake.

Assessment of dialysis adequacy among hemodialysis patients

Objective:- the study amid to assess dialysis adequacy among hemodialysis patients with end-stage renal disease. Methodology: A descriptive anon-probability (purposive sample) of (174) male and female hemodialysis patients in al-Najaf al-Ashraf city of patients with end -stage kidney disease and undergoing hemodialysis. Most patients were diagnosed with ESRD > one year ago from those who have spent more than twelve months on maintenance hemodialysis schedule. Data collected through using of a well-designed questionnaire consist of Three, part one consists of sociodemographic contain (7) items, and part two consists of medical data contain (7) items, Data was obtained from the patients undergoing hemodialysis by the interview. which include The form was based on preliminary assessment which checked the factor that influenced duration of disease ,period of session hemodialysis ,complication of hemodialysis and the adequacy of hemodialysis . The study was conducted at AL-Najaf AL-Ashraf City /AL Sadder Medical City and AL-Hakeem General Hemodialysis Center the study was begun from September 9th2021 to June 22th 2022. Data was analyzed by using of descriptive data analysis (frequencies, percentages, mean, standard deviation, person correlation). Results: The results of measurement of adequacy of 174 patient, about (35.1%) achieved adequate and (64.9%) did not achieve adequacy.

Effective ionic dialysis—a modern perspective for assessing dialysis adequacy

Effective ionic dialysis—a modern perspective for assessing dialysis adequacy

Is health-related quality of life associated with adequacy of hemodialysis in chronic kidney disease patients?

IntroductionMonitoring Health Related Quality of Life (HRQoL) in different stages of chronic kidney disease is advised by all nephrology societies. We aimed to study the relation between quality of life and dialysis adequacy.MethodsOne hundred patients (51% males), on regular hemodialysis 3/week for > 6 months in two hospitals were included. Single pool Kt/V was used to assess dialysis adequacy. Patients were grouped into 3 divisions according to Kt/v: Group A > 1.5 (n = 24), group B 1.2–1.5 (n = 54) and group C < 1.2 (n = 22). KDQOL-SF™ questionnaire was used to study quality of life in our groups. Group C was reassessed after 3 months of improving Kt/v.ResultsMean values were: Kt/V (1.48 ± 0.41), Cognitive Function (84.27 ± 9.96), Work status (30.00 ± 33.33), Energy (45.70 ± 13.89), Physical Function and Role limitations due to physical function (45.30 ± 12.39 and 31.25 ± 19.26, respectively). Group A had significantly higher scores of KDQOL-SF except Role limitations due to Physical Function. All subscales improved in group C after Kt/v improvement except 3 subscales, namely, work status, patient satisfaction and role limitation due to physical and emotional functions.ConclusionInadequate HD badly affects quality of life and improving adequacy refines many components of quality of life.

Assessing the Adequacy of Hemodialysis Patients via the Graph-Based Takagi-Sugeno-Kang Fuzzy System.

Maintenance hemodialysis is the main method for the treatment of end-stage renal disease in China. The Kt/V value is the gold standard of hemodialysis adequacy. However, Kt/V requires repeated blood drawing and evaluation; it is hard to monitor dialysis adequacy frequently. In order to meet the need for repeated clinical assessments of dialysis adequacy, we want to find a noninvasive way to assess dialysis adequacy. Therefore, we collect some clinically relevant data and develop a machine learning- (ML-) based model to predict dialysis adequacy for clinical hemodialysis patients. We collect 250 patients, including gender, age, ultrafiltration (UF), predialysis body weight (preBW), postdialysis body weights (postBW), blood pressure (BP), heart rate (HR), and blood flow (BF). An efficient graph-based Takagi-Sugeno-Kang Fuzzy System (G-TSK-FS) model is proposed to predict the dialysis adequacy of hemodialysis patients. The root mean square error (RMSE) of our model is 0.1578. The proposed model can be used as a feasible method to predict dialysis adequacy, providing a new way for clinical practice. Our G-TSK-FS model could be used as a feasible method to predict dialysis adequacy, providing a new way for clinical practice.

The Nitty-Gritties of Kt/Vurea Calculations in Hemodialysis and Peritoneal Dialysis.

In advanced Chronic Kidney Disease, patients require renal replacement therapy (dialysis or transplantation) for clearance of toxins, electrolyte and acid-base balance and removal of excess fluid. Dialysis adequacy should be taken into consideration in the adjustment of the dialysis prescription. Kt/Vurea is one method of measuring dialysis adequacy that is commonly used in clinical practice. Different formulae for calculating Kt/V are available. The appropriate Kt/V formula to be used depends on the clinical scenario, as well as parameters such as gender and size of patient, frequency of dialysis, mode of dialysis (ie hemodialysis vs, peritoneal dialysis), inter-dialysis weight gain, clinical symptoms, complications (fluid overload, hyperkalemia, intolerance to dialysis, etc), and residual kidney function. Nutrition parameters including serum protein and albumin levels, vitamin B12 and β2-microglobulin levels should be factored into the assessment of dialysis adequacy. In this review, we have described how Kt/Vurea is calculated in hemodialysis and peritoneal dialysis with examples. We reviewed the available literature by searching for papers related to calculating Kt/Vurea, single pool Kt/V, double pool Kt/V, weekly Kt/V, standard Kt/V, surface area normalized Kt/V, and various equations commonly practiced in clinical practice. We found several original articles, some review articles along with detailed information from manufacturers of different dialyzers published on their websites or as package inserts. Understanding the different equations available for calculating Kt/Vurea and the application of these results in the clinical setting is important for refining patient care and for designing clinical studies.

Assessment of hemodialysis adequacy: Correlation between online clearance monitoring and single pool Kt/V.

Objectives: The aim of this study is to correlate the dose of dialysis delivered by both methods in the dialysis population in our developing country. Study Design: Cross Sectional study. Setting: Dialysis Centre at Doctor’s Hospital and Medical Center Lahore. Period: February 1, 2018 to April 30, 2018. Material &amp; Methods: Using Fresenius 4008S machines equipped with OCM, we prospectively studied 41 hemodialysis patients. All patients were on hemodialysis for more than three months. Pre and post dialysis urea samples were collected for estimation of single pool Kt/V and compared with OCM. Results: The average age of the patients was 56.46 ± 13.82 years and the mean duration of dialysis was 28.9 ±35.22 months. Mean blood flow rate was 309.27 ±46.06 mL/min. The mean Kt/V was 1.51 ±0.216 (&lt;p=0.001) and the mean OCM was 1.47 ±0.191 (&lt;p=0.001). We found a positive correlation between the two parameters i.e a Pearson’s Correlation: 0.83 (&lt;p=0.001) and an R square value of 0.645.We found that OCM is a good indicator of Kt/V. However, it underestimated Kt/V by 2.07%±8.53%. Conclusion: Online Kt/V calculated by ionic dialysance is a useful method to estimate dialysis dose without the need of blood samples. In clinical practice Kt/V is done on a monthly basis. Any change in the dialysis prescription would entail repeat labs. OCM can be performed at each dialysis session at no extra cost and in real time. Thus, it can prove to be a helpful and economical tool in the assessment of dialysis adequacy in the low income countries with limited resources.

P1834MONITORING ANTICOAGULATION IN PEDIATRIC PATIENTS ON REGULAR HEMODIALYSIS: CAN A DREAM COME TRUE?

Abstract Background and Aims Anticoagulation in hemodialysis aims at preventing the activation of coagulation cascade during the procedure. Appropriate anticoagulation for hemodialysis (HD) requires a precise balance between under- and over-heparinization to prevent extracorporeal circuit (ECC) clotting and bleeding, respectively. This type of balance is practiced in hemodialysis centers, on daily basis, depending on each center’s experience and tailored to every patient, rather than in accordance to a clear guideline. Our aim was to objectively evaluate the adequacy of heparin therapy used for anticoagulation in pediatric patients on regular hemodialysis. Method A follow up observational study for 12 months including 44 pediatric end stage renal disease patients on regular hemodialysis through an A-V fistula or an A-V graft. We excluded patients with a known bleeding disorder, chronic liver disease, thrombophilia, vasculitis or receiving anticoagulation for any condition. All patients were subjected to thorough history taking including dialysis history, assessment of dialysis adequacy by calculating Kt/V and blood pressure monitoring before, during and after session. Clinical evaluation of anticoagulation was done through visual inspection of extra-corporeal circuit, observing transmembrane pressure and recording the duration of compression over the puncture site at the end of the hemodialysis session. Biological monitoring was done by Bedside Activated clotting time (ACT) test. Results On initial evaluation of patients, 11 cases had either clotting or bleeding clinically (only 4 had abnormal ACT values), being on either hemodialysis (HD) or hemodiafilteration (HDF) and receiving unfractionated heparin (UFH) either as a bolus or through a pump. They were further evaluated after being put; on HDF and a heparin pump and showed neither clotting nor bleeding though 2 cases had prolonged predialysis ACT values. On HDF and heparin bolus, no bleeding or clotting were detected though 3 cases had abnormal predialysis ACT values. On HD and heparin pump no bleeding or clotting were detected, 2 cases had low kt/V, a case had abnormal ACT values (5 minutes, 1 hour and at the end ACT values). Conclusion Hemodialysis mode, rather than method of heparin delivery, had a bigger impact on correcting clinical defects of anticoagulation in our patients. ACT as a bedside test of anticoagulation adequacy during HD sessions did not offer extra benefit over clinical evaluation, which is still considered a more accurate method.

Is dialysis adequacy a useful predictor for sexual function in males and females with end-stage renal disease?

IntroductionThe development of sexual dysfunction (SD) in dialysis patients is multifactorial. We aimed to evaluate whether adequate dialysis had an effect on the development of SD in male and female patients undergoing dialysis due to end stage renal disease. Anxiety, depression, health-related quality of life and the other risk factors related to dialysis were also evaluated in terms of SD. MethodsSeventy men and 57 women undergoing haemodialysis (HD) or peritoneal dialysis (PD) and 65 healthy male volunteers and 48 healthy female volunteers, age-matched, were included in the study. The International Index of Erectile Function, Female Sexual Function Index, Beck Depression Inventory, Beck Anxiety Inventory and The Short Form-36 Health Survey were applied to all participants. The cut off value of Kt/V was determined as 1.3 for HD and 1.7 for PD to assess dialysis adequacy. Per gender, all the participants were divided into three groups as control, adequate dialysis and non-adequate dialysis. ResultsDialysis adequacy [OR: 3.225, 95%CI (1.213–8.620), p=.019] was found as a more decisive factor for male SD, while dialysis adequacy [OR: 3.015, 95%CI (.991–7.250), p=.041] and depression [OR: 4.280, 95%CI (1.705–10.747), p=.002] were more significant for female SD. In addition, a strong relationship was found between male SD and physical functioning (r: .524, p=.032), social functioning (r: .565, p=.042), general health (r: .693, p=.037) perception, while female SD was found to be strongly associated with anxiety (r: −.697, p=.002) and depression (r: −.738, p=.001). DiscussionDialysis adequacy was found to be the most important factor in reducing SD. Non-adequate dialysis resulted in worse sexual function, higher levels of depression and anxiety. Its negative effect on health-related quality of life was only seen in men.

Effect of branched chain amino acid supplementation on dialysis adequacy and nutritional parameters in hemodialysis patients.

Malnutrition in hemodialysis (HD) patients is caused by deficient nutrient and protein intake and has a negative impact on patient outcomes. The assessment of dialysis adequacy in these patients depends to a large extent on the calculation of urea clearance using dialyzer clearance of urea (K) multiplied by the duration of the dialysis treatment (t, in minutes) divided by the volume of distribution of urea in the body (V, in mL); Kt/V. This study aims to detect the effect of branched-chain amino acid (BCAA) supplementation on Kt/V and other nutritional parameters such as serum albumin as well as body mass index. Forty-six patients from the HD Unit of Mostafa Mahmoud Hospital were included in this study. Daily intake of BCAA was continued for three months. At the start of the study, before the intervention, and at the end of the 3rd month, we measured serum albumin, valine, leucine, iso-leucine, and Kt/V. Analysis of data was performed using paired and independent t-test. We found that BCAA has a highly significant effect on increasing the level of albumin, leucine, isoleucine, valine, and Kt/V in HD patients (P <0.001) (Paired t-test). BCAA supplements could be used in this patient population to improve dialysis adequacy and outcome.

Glutathione Transferase P1-1 an Enzyme Useful in Biomedicine and as Biomarker in Clinical Practice and in Environmental Pollution

Glutathione transferase P1-1 (GSTP1-1) is expressed in some human tissues and is abundant in mammalian erythrocytes (here termed e-GST). This enzyme is able to detoxify the cell from endogenous and exogenous toxic compounds by using glutathione (GSH) or by acting as a ligandin. This review collects studies that propose GSTP1-1 as a useful biomarker in different fields of application. The most relevant studies are focused on GSTP1-1 as a biosensor to detect blood toxicity in patients affected by kidney diseases. In fact, this detoxifying enzyme is over-expressed in erythrocytes when unusual amounts of toxins are present in the body. Here we review articles concerning the level of GST in chronic kidney disease patients, in maintenance hemodialysis patients and to assess dialysis adequacy. GST is also over-expressed in autoimmune disease like scleroderma, and in kidney transplant patients and it may be used to check the efficiency of transplanted kidneys. The involvement of GSTP in the oxidative stress and in other human pathologies like cancer, liver and neurodegenerative diseases, and psychiatric disorders is also reported. Promising applications of e-GST discussed in the present review are its use for monitoring human subjects living in polluted areas and mammals for veterinary purpose.

The relationship between dialysis adequacy and the rate of change in uric acid level by hemodialysis

Aim: Although one of the commonly used methods for determining dialysis adequacy is the urea kinetic model, it is not the gold standard. Different parameters are needed to determine dialysis adequacy. In our study, we investigated the relationship between urea reduction rate (URR) and Kt/V which are used to assess dialysis adequacy and the rate of change in uric acid, a purine metabolite, by hemodialysis.Methods: A total of 133 patients who had undergone hemodialysis treatment due to renal failure between March 2010 and September 2010 were evaluated retrospectively. Urea kinetic modeling was used to measure dialysis adequacy. The following formula was used to do this; Kt/V=-ln(R-0.008xT)+(4-3.5xR)xUF/W[R; postdialysis blood ureanitrogen (BUN)/predialysis BUN, T; duration of dialysis (hr), UF; total ultrafiltration during dialysis (L), W; patient weight after dialysis (kg)]. The urea reduction rate was calculated using the formula; URR(%)=100x(1-postdialysis BUN/predialysis BUN). Uric acid reduction rate (UARR) was calculated using the formula; UARR(%)=100x(1-Uric acid after/Uric acid before). The relationship between URR and Kt/V ratios which are used to assess dialysis adequacy and UARR is evaluated.Results: Median urea, uric acid and creatinine reduction rates were 72%, 74% and 63.9%, respectively. There was a statistically significant correlation between reduction rates of uric acid, creatinine and urea after dialysis (p&lt;0.001). There was a statistically significant relationship between URR and Kt/V which are used to assess dialysis adequacy,and UARR (p&lt;0,001). According to the ROC analysis in our study, we defined UARR value that will demonstrate dialysis adequacy as at least 65.8% (sensitivity 97.9% and specificity 82.6%, area under the ROC curve=0.880, p&lt;0.001).Conclusion: A significant relationship was found between the URR and Kt/V ratios which are used to assess dialysis adequacy and UARR. We also determined in our study that the UARR value that shows dialysis adequacy should be at least 65.8%. To our knowledge, this is the first study to evaluate the relationship between UARR and dialysis adequacy. However, thefindings need to be confirmed by large, prospective, clinical trials.

Assessment of dialysis adequacy: beyond urea kinetic measurements

Adequacy of dialysis is a term that has been used for many years based on measurement of small solute clearance using urea and creatinine. This has been shown in some but not all studies in adults to correlate with survival. However, small solute clearance is just one minor part of the effectiveness of dialysis and in fact ‘optimum’ dialysis, rather than ‘adequate’ dialysis is what most paediatric nephrologists would want for their patients. Additional ways to assess the success of dialysis in children would include dialysis access complications and longevity, preservation of residual kidney function, body composition, biochemical and haematological control, nutrition and growth, discomfort during the dialysis process and psychosocial adjustment including hospitalisation and school attendance. These criteria need to be balanced against a dialysis programme that has the least possible adverse effects on quality of life.

Should we look beyond Kt/V urea in assessing dialysis adequacy?

Since the advent of maintenance dialysis therapy, our interpretation of what adequate dialysis really is has broadened and become more controversial. This is not only due to our changing and aging dialysis population but also to our evolving knowledge base. As nephrologists, we strive to achieve both quality and (often) quantity of life for our patients and we feel reassured when we have a quantifiable marker to show for our efforts. However, we suggest that adequate dialysis reaches far beyond the realms of attaining a particular biochemical result. Dialysis adequacy should encompass a more comprehensive assessment of patient well-being. This metric could comprise quality of life and patient-specified goals, sufficient small solute and middle molecule clearance, optimal blood pressure control, and effective bone-mineral balance, all in the context of minimizing mortality and morbidity, and a livable dialysis regimen for the patient.

Simple method to estimate daily sodium intake during measurement of dialysis adequacy in chronic peritoneal dialysis patients.

Restriction of dietary sodium intake for peritoneal dialysis (PD) patients is recommended, but there is limited information on the measurement and monitoring of sodium intake. We have developed a simple method to estimate daily sodium intake during the measurement of dialysis adequacy in PD patients. A total of 83 PD patients were enrolled in the study. The patients were divided into two groups based on residual renal function (RRF). We measured total sodium removal and estimated daily sodium intake using dietary recall for one day, during the assessment of dialysis adequacy. There were 39 patients in the RRF(-) group and 44 in the RRF(+) group. In both groups, and all patients, there were significant positive correlations between sodium intake and total sodium removal: RRF(-) group, r=0.598; RRF(+) group, r=0.577; total patients, r=0.595. There were linear relationships between dietary sodium intake and total sodium removal in both groups: RRF(-) group, sodium intake (mg/d) = 19.3 × peritoneal sodium removal (mEq/d) + 211;RRF(+) group, sodium intake (mg/d) = 15.4 × total sodium removal (mEq/d) + 609. All PD patients, sodium intake (mg/d) = 15.6 × total sodium removal (mEq/d) + 646. The measurement of total sodium removal during the assessment of dialysis adequacy could be an effective and simple method to estimate dietary sodium intake in PD patients. A dietary intake of 2,000 mg of sodium corresponds to a total sodium removal of approximately 87 mEq/d.

SiRNA Therapeutics for Primary Hyperoxaluria: A Beginning

Realization of the early promise of gene therapy has been elusive. Long and eagerly anticipated, particularly for orphan diseases with few available therapeutic alternatives, only within recent years have such treatments begun to reach phase III clinical trials.1 Two articles in this issue of Molecular Therapy identify inhibition of glycolate oxidase as a potential treatment for type 1 primary hyperoxaluria (PH1), an autosomal recessive condition in which excess oxalate produced by the liver causes kidney damage and severe systemic disease. Both teams of investigators demonstrated reduction in oxalate production in a mouse knockout model of the disease through absence or inhibition of glycolate oxidase (GO). Hepatic GO converts glycolate to glyoxylate, which is the primary substrate for production of oxalate. Thus, substrate reduction was achieved. Martin-Higueras and colleagues2 demonstrated that the hyperoxaluria of the AGXT knockout mouse was substantially reduced following double knockout of AGXT and GO. Dutta and colleagues3 approached the problem differently, using Dicer-short interfering RNA (Dicer-siRNA) for inhibition targeting hydroxyacid oxidase 1 (HAO-1) messenger RNA, which encodes GO.3 Using this approach, they were able to demonstrate normalization of oxalate production in hepatocytes of AGXT knockout mice. These observations suggest an innovative approach to treatment for patients with PH1 and impart new hope for patients with PH, their families, and the physicians who care for them. This is especially true in that early experience with other applications of siRNA for treatment of human diseases, including amyloidosis, hypercholesterolemia, and α1-antitrypsin deficiency, has been encouraging.1,4

Solute clearance measurement in the assessment of dialysis adequacy among African continuous ambulatory peritoneal dialysis patients.

Solute clearance measurement is an objective means of quantifying the dose of peritoneal dialysis (PD). Despite continued debate on the interpretation and precise prognostic value of small solute clearance in PD patients, guidelines based on solute clearance values are common in clinical practice. There is limited information on the solute clearance indices and PD adequacy parameters among this predominantly low socioeconomic status PD population. We investigated the solute clearance among continuous ambulatory peritoneal dialysis (CAPD) patients at the Charlotte Maxeke Johannesburg Academic Hospital and its relationship with other parameters of PD adequacy. Seventy patients on CAPD were studied in this cross-sectional study. Solute clearance was assessed using urea clearance (Kt/V). Linear regression analysis was used to determine factors associated with solute clearance, while analysis of variance was used to test the influence of weekly Kt/V on blood pressure (BP), hemoglobin (Hb) and other biochemical parameters. The mean age of the study population was 37.9 ± 12.4 years, 43% were females and 86% were black Africans. The mean duration on CAPD was 19.7 ± 20.8 months. Mean systolic and diastolic BP were 144 ± 28 and 92 ± 17 mm Hg, respectively. The mean Hb was 11.1 ± 2.2 g/dL and the mean weekly Kt/V was 1.7 ± 0.3. Factors like systolic BP, Hb level, serum levels of cholesterol, calcium, phosphate, parathyroid hormone and albumin were not significantly associated with the weekly Kt/V. We conclude that the dose of PD received by the majority of our patients in terms of the weekly Kt/V is within the recommended values and that this finding is significant considering the low socioeconomic background of our patients. There is no significant association between Kt/V and other indices of dialysis adequacy.

Oxalate Quantification in Hemodialysate to Assess Dialysis Adequacy for Primary Hyperoxaluria

Background: Patients with primary hyperoxaluria (PH) overproduce oxalate which is eliminated via the kidneys. If end-stage kidney disease develops they are at high risk for systemic oxalosis, unless adequate oxalate is removed during hemodialysis (HD) to equal or exceed ongoing oxalate production. The purpose of this study was to validate a method to measure oxalate removal in this unique group of dialysis patients. Methods: Fourteen stable patients with a confirmed diagnosis of PH on HD were included in the study. Oxalate was measured serially in hemodialysate and plasma samples in order to calculate rates of oxalate removal. HD regimens were adjusted according to a given patient's historical oxalate production, amount of oxalate removal at dialysis, residual renal clearance of oxalate, and plasma oxalate levels. Results: After a typical session of HD, plasma oxalate was reduced by 78.4 ± 7.7%. Eight patients performed HD 6 times/week, 2 patients 5 times/week, and 3 patients 3 times/week. Combined oxalate removal by HD and the kidneys was sufficient to match or exceed endogenous oxalate production. After a median period of 9 months, pre-dialysis plasma oxalate was significantly lower than initially (75.1 ± 33.4 vs. 54.8 ± 46.6 mmol/l, p = 0.02). Conclusion: This methodology can be used to individualize the dialysis prescription of PH patients to prevent oxalosis during the time they are maintained on HD and to reduce risk of oxalate injury to a transplanted kidney.

COMPARISON OF Kt/V AND UREA REDUCTION RATIO IN MEASURING DIALYSIS ADEQUACY IN PAEDIATRIC HAEMODIALYSIS IN ENGLAND

The National Kidney Foundation-Dialysis Outcomes Quality Initiative (KDOQI) guidelines and the Renal Association recommend the use of either Kt/V or urea reduction ratio (URR) to measure haemodialysis adequacy. To determine the methods used to measure paediatric haemodialysis adequacy and to assess consistency between calculations of single pool Kt/V (spKt/V) and URR. A service evaluation was conducted to establish current practices in measuring dialysis adequacy. A prospective longitudinal study was conducted to compare spKt/V and URR. Thirty-two children were recruited consisting of 13 males and 19 females in five paediatric dialysis centres. Inconsistencies were reported of the method of post-urea sampling with 4 of the 10 centres using the KDOQI recommended sampling method. Five dialysis centres reported using URR and five reported using spKt/V. There were substantial differences between the two measures. Using URR suggested that up to 44% of children did not receive adequate dialysis, whereas measurement by spKt/V suggested no more than 6% of the same dialysis sessions were not adequate. One standard measure should be used to assess dialysis adequacy in paediatric centres in England. KDOQI guidelines were not consistently followed in obtaining a post-urea blood sample and this procedure should be standardised.