Long-Term Evaluation of Colestilan in Chronic Kidney Disease Stage 5 Dialysis Patients with Hyperphosphataemia.

BACKGROUND: This study investigated in a North American patient population the longer-term treatment effects of the phosphate binder, colestilan, in patients with CKD Stage 5D and hyperphosphataemia. METHODS: One hundred and sixteen CKD Stage 5D patients with hyperphosphataemia were entered into a multi-centre, open-label study where they received flexible dose colestilan (6-15 g/day) to maintain serum phosphorus levels between 3.5 and 5.5 mg/dl. The primary endpoint was safety, assessed by treatment-emergent adverse events. Efficacy was assessed by changes in serum phosphorus, mineral metabolism, lipids, HbA1c, uric acid and bone markers. RESULTS: Serum phosphorus was significantly reduced by 1.18 mg/dl (p < 0.001), from 6.99 mg/dl at baseline to 5.80 mg/dl at week 52. LDL-cholesterol was also significantly reduced as well as uric acid. Significant change was observed only for one bone marker - PINP. Most adverse events were of mild or moderate intensity. Nausea (22.4%), vomiting (21.6%), and diarrhoea (19.8%) were most commonly reported. CONCLUSIONS: Long-term flexible dosing with colestilan reduces serum phosphorus and demonstrates an acceptable safety and tolerability profile.

Haemodialysis session: the perfect storm for vascular calcification.

INTRODUCTION: Vascular calcification (VC) associated to chronic kidney disease (CKD) is a complex phenomenon closely related to mineral bone metabolism disorders. Many are the factors implicated, as the drugs used in the treatment of CKD. Some in vitro studies suggest that electrolyte and acid-base disorders induced by hemodialysis (HD) may play a key role in VC. METHODS: We analyzed electrolyte and acid-base disorders that occur during an HD session in 26 patients randomly assigned to 1,25 mM or 1,5 mM calcium bath. RESULTS: There is a calcium load in all the patients, independently of calcium bath concentration or basal serum calcium levels. At the end of the session, 100% of the patients dialyzed with 1,5 mM calcium bath have calcium serum levels > 1,3 mM. However, this only occurs in 15% of the patients dialysed with 1,25 mM calcium bath. During this calcium load, phosphorus levels persist uncontrolled. Besides, there is a progressive alkalinization in all the patients. In the end of the session 50% have serum bicarbonate > 30 mM and 23% pH > 7,5. CONCLUSIONS: During HD sessions occur electrolyte and acid-base disorders that induce VC: Calcium load and alkalization in presence of elevated phosphorus levels. It is necessary to perform studies with kinetic models of calcium load and alkalinization different from the actual ones.

[Online hemodiafiltration in children and hypoparathyroidism: a single-centre series of cases]. / Hémodiafiltration online et hypoparathyroïdie chez l'enfant : une série de cas monocentrique.

BACKGROUND: Due to technical requirements and cost, hemodiafiltration (HDF) is not widely used in pediatrics. We have been using online HDF (oHDF) since 2009 and we observed low parathyroid hormone (PTH) levels despite the accurate management of CKD-MBD. METHODS: We reviewed the medical charts and parameters of mineral metabolism assessed on a before/after session basis in the 6 children undergoing chronic oHDF in our centre. RESULTS: We observed low (<80pg/mL) PTH levels in all 6 patients and very low (<45pg/mL) PTH levels in 5, two of them presenting with pathological fractures. These low PTH levels were reversed after decreasing calcium concentration to 1.25 mmol/L in the dialysate, suggesting that high-efficiency oHDF may expose children to calcium during sessions in a too important amount when using 1.5 mmol/L dialysates. Last, C-terminal FGF23 levels before sessions were relatively low (<1600RU/mL), with a 32% clearance by oHDF. CONCLUSION: PTH levels should be closely monitored in pediatric oHDF and solutions with a calcium concentration of 1.25 mmol/L should be used as first line in these patients.

Injectable treatments for noninsertional achilles tendinosis: a systematic review.

BACKGROUND: Although there has been a recent increase in interest regarding injectable therapy for noninsertional Achilles tendinosis, there are currently no clear treatment guidelines for managing patients with this condition. The objective of this study was (1) to conduct a systematic review of clinical outcomes following injectable therapy of noninsertional Achilles tendinosis, (2) to identify patient-specific factors that are prognostic of treatment outcomes, (3) to provide treatment recommendations based on the best available literature, and (4) to identify knowledge deficits that require further investigation. METHODS: We searched MEDLINE (1948 to March week 1 2012) and EMBASE (1980 to 2012 week 9) for clinical studies evaluating the efficacy of injectable therapies for noninsertional Achilles tendinosis. Specifically, we included randomized controlled trials and cohort studies with a comparative control group. Data abstraction was performed by 2 independent reviewers. The Oxford Level of Evidence Guidelines and GRADE recommendations were used to rate the quality of evidence and to make treatment recommendations. RESULTS: Nine studies fit the inclusion criteria for our review, constituting 312 Achilles tendons at final follow-up. The interventions of interest included platelet-rich plasma (n = 54), autologous blood injection (n = 40), sclerosing agents (n = 72), protease inhibitors (n = 26), hemodialysate (n = 60), corticosteroids (n = 52), and prolotherapy (n = 20). Only 1 study met the criteria for a high-quality randomized controlled trial. All of the studies were designated as having a low quality of evidence. While some studies showed statistically significant effects of the treatment modalities, often studies revealed that certain injectables were no better than a placebo. CONCLUSIONS: The literature surrounding injectable treatments for noninsertional Achilles tendinosis has variable results with conflicting methodologies and inconclusive evidence concerning indications for treatment and the mechanism of their effects on chronically degenerated tendons. Prospective, randomized studies are necessary in the future to guide Achilles tendinosis treatment recommendations using injectable therapies. LEVEL OF EVIDENCE: Level II, systematic review.

Hemodialysis in chronic kidney disease--balancing fluid and salt on the inflammation tightrope.

Haemodialysis (HD) is a well-established, longstanding, and life-saving treatment for patients with chronic kidney disease (CKD) or acute kidney injury (AKI). However, side-effects of HD in CKD patients are numerous and remain problematic. Amongst others, CKD patients are susceptible to short-term effects caused by abnormalities in water and electrolyte balance and long-term effects related to sustained inflammation short-term side-effects of HD such as errors in sodium content of dialysate could readily be overcome by correct baseline labelling of dialysates and the ongoing rigorous implementation of safety procedures by staff nurses and physicians. The proper implementation of biofeedback systems, with tight safety alarm limits and conductivity based detection systems including the analysis of ionic mass balance could have prevented the shortfalls described. Long-term untoward effects of HD are mainly due to sustained inflammation and are correlated with higher morbidity and mortality. Unfortunately, the pathophysiologic mechanisms that underpin the inflammatory processes induced by HD remain poorly understood or incompletely unravelled. Within the wide array of inflammatory (inter)actions, cytokines are undoubtedly key players but interesting biomarkers (e.g. follistatin) and pathways (e.g. erythropoietin hyporesponsiveness) have come into play. Therapeutic interventions in differing fields such as vascular access, avoidance of intra-dialytic hypotension and pharmacologic interventions with statins, angiotensin II receptor antagonists or vitamine D supplementation may be of significance. However, confirmatory trials investigating of all these promising therapies are, as yet, lacking. The impact of the dialysis technique itself should not be underestimated.

Peritoneal dialysis as a therapeutic approach in congestive heart failure resistant to pharmacological treatment.

Given an increasing number of patients with congestive heart failure (CHF) refractory to diuretics, new and more effective therapeutic modalities are sought. Peritoneal dialysis (PD), which provides continuous, slow ultrafiltration, may be an alternative to hemodialysis in this population. The current paper, based on a comprehensive literature review, addresses the role of PD in improving the quality of life of patients with CHF.

Efeito benéfico da correção da acidose metabólica no estado nutricional de pacientes em hemodiálise / Beneficial effects of metabolic acidosis correction in hemodialysis patients

Objetivo: Avaliar o efeito da correção da acidose metabólica no estado nutricional de pacientes em hemodiálise. Métodos: Foram estudados, durante seis meses, 20 pacientes com acidose metabólica, definida pela média de tr~es mensurações de bicarbonato sérico pré-diálise <22 mEq/L. os pacientes dialisavam há, pelo menos, seis meses, utilizando bicarbonato de 35 mEq/L no dialisato. A correção da acidose metabólica foi feita mediante elevação do bicarbonato no dialisato para valores que não ultrapassaram 40 mEq/L, objetivando um bicarbonato sérico entre 22-26 mEq/L. Foram avaliados no início e no final do estudo: avaliação antropométrica, dietética, bioquímica e Avaliação subjetiva Global (ASG). Resultados: A avaliação nutricional na fase inicial do estudo demonstrou índice de massa corporal normal (24,23 +- 3,83 Kg/m²). A circunferência muscular do braço, a prega cutânea tricipital e a ASG classificaram homens e mulheres como desnutridos. Os consumos de calorias e proteínas foram 29,7 +- 10,1 Kcal?kg/dia e 1,31 +- 0,35 g/Kg/dia, respectivamente. A avaliação bioquímica observou albumina sérica normal e colesterol reduzido. Após correção, bicarbonato sérico e pH aumentaram de 18,2 +- 1,64 para 22 +- 1,70 (p<0,001), e de 7,32+- 0,45 para 7,37 +-0,41 (p<0,001), respectivamente. Houve melhora da ASG (21,7 +- 6,4 versus 16,8 +-6,6, p<0,0001) e aumento na ingestão calórica (1.892,61 +-454,30 versus 2.110,30 +-869,24, p<0,05). Conclusão: A suplementação de bicarbonato na solução de hemodiálise foi método efetivo para a correção da acidose metabólica, determinando aumento da ingestão calórica e melhora nos escores da ASG.

Objective: To evaluate the effect of correction of metabolic acidosis on nutritional status of hemodialysis patients. Methods: We studied for six months, 20 patients with metabolic acidosis, defined as the average of tr ~ s measurements of predialysis serum bicarbonate <22 mEq / L. patients receiving dialysis treatment for at least six months, using bicarbonate of 35 mEq / L in the dialysate. The correction of metabolic acidosis was observed in the high bicarbonate dialysate for values that exceeded 40 mEq / L, aiming for a serum bicarbonate between 22-26 mEq / L. Were assessed at baseline and at the end of the study: anthropometric, dietary, biochemical and Subjective Global Assessment (SGA). Results: The nutritional assessment in the initial phase of the study showed normal BMI (24.23 + - 3.83 kg / m²). The arm muscle circumference, triceps skinfold and the ASG men and women classified as malnourished. The intake of calories and protein were 29.7 + - 10.1 Kcal? Kg / day and 1.31 + - 0.35 g / kg / day, respectively. The biochemical evaluation showed normal serum albumin and low cholesterol. After correction, serum bicarbonate and pH increased from 18.2 + - 1.64 for 22 + - 1.70 (p <0.001), and 7.32 + - 0.45 to 7.37 + -0.41 ( p <0.001), respectively. There was improvement in ASG (21.7 + - 6.4 versus 16.8 + -6.6, p <0.0001) and increased caloric intake (1892.61 + -454.30 vs 2110.30 + -869 , 24, p <0.05). Conclusion: Supplementation of bicarbonate in the dialysis solution was an effective method for correction of metabolic acidosis, determining increased caloric intake and improvement in the scores of the ASG.

[Phosphorus (P) chelant in dialysis: efficacy and cost. Peritoneal dialysis solutions]. / Quelantes de fósforo (P) en diálisis: eficacia y coste. Soluciones de diálisis peritoneal.

Sevelamer use has a high prevalence, and half of patients are treated with this noncalcium binder. Two randomized studies appeared in 2007 that compared the efficacy of sevelamer over calcium salts. In the more statistically potent of the two studies, no differences were found in mortality between the sevelamer and calcium groups, except for a benefit in favor of sevelamer in patients older than 65 years. In the other less statistically potent study, lower mortality was observed in the sevelamer group. Both studies have various deficiencies and a timely meta-analysis of the two studies appearing that same year concluded that there was no significant evidence demonstrating a superior efficacy of sevelamer over calcium salts. Therefore, generalized extension of its use as a first-line binder is not recommended. However, its use can be assessed in specific clinical situations. With regard to the cost-benefit ratio, as there is no evidence that greater clinical benefits are obtained with sevelamer than with calcium salts, prudence and moderation in its use are needed because of the high cost/benefit ratio demonstrated. Otherwise, we will contribute to increasing the already very high treatment cost in these patients, with one of the highest costs per life year gained in medicine. The cost/benefit ratio of sevelamer remains unattractive from an economic point of view, even if dialysis and transplant are excluded in these patients.

Continuous venovenous hemofiltration with citrate-based replacement fluid: efficacy, safety, and impact on nutrition.

BACKGROUND: Citrate-based continuous venovenous hemofiltration (CVVH) replacement fluids provide effective and simple regional anticoagulation. However, concern over toxicity has limited citrate use, especially at the high filtration rates advocated for better outcomes. We used volumes of 72 L/d in patients at high risk for bleeding and investigated the treatment's efficacy, safety, and clinical results, especially with regard to nutrition supplementation. METHODS: A standard replacement solution (trisodium citrate, 13.3 mmol/L) was infused at up to 3 L/h in predilution CVVH, and ultrafiltration was increased further for net fluid removal. Calcium was repleted centrally. We retrospectively evaluated metabolic control, citrate toxicity, circuit patency, hemorrhagic complications, hemodynamics, vasopressor use, nutrition, renal recovery, and mortality. RESULTS: Seventy-six patients with 766 CVVH patient-days were analyzed. Mean replacement fluid rate was 31 mL/kg/h (35 mmol/h of citrate), with hemofiltration of 35 mL/kg/h (67 +/- 11 L/d). No significant bleeding, citrate toxicity, or hypocalcemia was observed, and 74% required additional alkali therapy. Dialyzer patency was 58% at 48 hours. Control of fluid, electrolytes, and azotemia was excellent (serum creatinine level, 1.7 mg/dL [150 micromol/L]; blood urea nitrogen, 42 mg/dL [15 mmol/L]). Fluid removal permitted protein (1.7 g/kg/d) and calorie (30 kcal/kg/d) nutrition in high fluid volumes. Vasopressor use and central pressures decreased significantly. Cumulative 28-day intensive care unit survival was 58%, and 41% of these patients had renal recovery in the intensive care unit. Thirty percent of the entire cohort survived the hospitalization, and 53% of these patients recovered renal function. CONCLUSION: CVVH with 3 L/h of citrate-based replacement fluid is a safe, efficient, and simple technique in patients at high risk for bleeding. It allows superb control of uremia and fluid balance and thereby permits aggressive nutritional support.

Comparative survival analysis of urea kinetic based indices.

BACKGROUND: Although urea kinetic modeling indices for measuring dialysis dose are recommended by world expert groups, it is not quite clear whether some of these are superior in predicting the outcome over others. This prospective, single-center study was carried out with the aim to compare predictive value of different indices and methods of measuring dialysis dose. METHODS: The analysis included 93 anuric patients having been on hemodialysis for at least 2 years who were followed-up for 75-months. The dialysis dose was measured by Kt/V (formal UKM, 3 and 2 urea samples), Kt/V (Daugirdas), Kt/V (Lowrie), eKt/V (Daugirdas), URR and TAC urea. RESULTS: Correlations between dialysis indices and survival time were significant for all indices (p<0.01) except for TAC. All indices, except for TAC urea, were significant predictors of mortality (multivariate Cox regression analysis; p<0.01) and differences of significant levels among these colinear parameters were small. CONCLUSION: All examined indices except for TAC urea were highly predictive of patient mortality. Daugirdas and Lowrie simplified Kt/V indices are as predictive of all-cause mortality as more complex formal UKM methods in long-term patients on a 3x4h/week schedule.

Nocturnal but not short hours quotidian hemodialysis requires an elevated dialysate calcium concentration.

Interest in quotidian (daily) hemodialysis (HD) is growing. Some advocate short-hours high-efficiency daily HD (SDH) and others long-hours slow-flow nocturnal HD (NH) while the patient is asleep, both being used 5 to 7 d/week. The London Daily/Nocturnal Hemodialysis Study was the first attempt to obtain data of SDH and NH that may be compared with conventional thrice weekly HD (CH). This was a 4-yr observational study designed to enter and follow 40 patients: 10 receiving SDH, 10 receiving NH, and 20 receiving CH. The CH patients were cohort control subjects matched for each SDH and NH patient by age, gender, comorbidity, and original dialysis modality (in-center, home, self-care, or satellite HD). All SDH and NH treatments were at home. Data collection to December 2001 was analyzed. Then enrollment had been completed and all patients had been followed for 15 mo, eight SDH plus six NH for 18 mo, seven SDH plus six NH for 21 mo, and seven SDH and five NH for 24 mo. This report gives data on calcium and phosphorus metabolism in these patients. All patients were initially dialyzed against a 1.25-mmol/L calcium bath. Predialysis serum calcium levels became lower in NH versus SDH patients by the first month and at 9 mo were 2.67 +/- 0.25 mmol/L (M +/- SD) in SDH, 2.40 +/- 0.16 mmol/L in NH, and 2.52 +/- 0.21 mmol/L in CH (SDH versus NH, P = 0.038; SDH versus CH versus NH, NS). Predialysis phosphorus levels were better controlled by NH than by SDH or CH, and with NH, all phosphate binders were discontinued. By 12 mo, a rise in bone alkaline phosphatase was seen in NH patients (but not in SDH or CH patients), which peaked at 15 to 18 mo (NH 191 IU/L +/- 70; SDH 82 +/- 34; CH 80 +/- 36; P < 0.002) and similarly with intact parathyroid hormone (iPTH) levels (NH 159 pmol/L +/- 75; SDH 13.1 +/- 10; CH 18 +/- 18; P < 0.00001). Because of these changes, the dialysate calcium concentration was increased to 1.75 mmol/L for the NH patients. Postdialysis calcium then rose to 2.57 +/- 0.21, and alkaline phosphatase and iPTH normalized completely by 21 mo. These observations prompted mass balance studies that showed that a 1.25-mmol/L calcium dialysate was associated with a mean net calcium loss of 2.1 mmol/h of dialysis time, whereas 1.75-mmol/L calcium dialysate provides a net gain of 3.7 mmol/h. In addition, the mass balance studies showed that phosphate removal by NH (43.5 +/- 20.7 mmol) was significantly (P < 0.05) higher than by SHD (24.2 +/- 13.9 mmol) but not by CH (34.0 +/- 8.7 mmol) on a per-treatment basis. With the increased frequency of treatments provided by quotidian dialysis, the weekly phosphorus removal (261.2 +/- 124.2 mmol) by NH was significantly higher than by SDH (P = 0.014) and CH (P = 0.03). This allowed the discontinuation of P binders in the NH group, which in turn eliminated approximately 8 g elemental Ca/wk oral intake. This, together with a 4 g elemental Ca/wk dialysate loss induced by a 1.25-mmol/L Ca bath, explains the changes in Ca, alkaline phosphatase, and iPTH seen in the NH patients. The SDH patients have weekly dialysis times similar to CH and still require P binders and do not become Ca deficient using 1.25-mmol/L Ca dialysate. With NH but not SDH, an elevated dialysate Ca concentration is required.

Does amino acid-based peritoneal dialysate change homocysteine metabolism in continuous ambulatory peritoneal dialysis patients?

OBJECTIVE: We examined whether amino acid-based peritoneal dialysate that contains 85 mg/dL L-methionine affects homocysteine (Hcy) metabolism. DESIGN: The study enrolled 17 adult CAPD patients (11 men, 6 women) who had been receiving CAPD for at least 6 months and who had low serum albumin levels (<3.7 g/dL). Diet was not specifically changed. All of the study patients received daily 4-exchange CAPD treatment, and they used Nutrineal (Baxter Healthcare, Deerfield, IL, U.S.A.) as one of their daily exchanges (first or second exchange). Blood samples were collected every 2 weeks, and Hcy was measured. RESULTS: After use of Nutrineal, serum albumin was unchanged, but blood urea nitrogen (BUN) and total protein were increased. Before the study began, 1 patient had a very high Hcy level (256 micromol/L); his data were excluded from the analysis. In the remaining 16 patients, baseline Hcy was 24.4 +/- 7.0 micromol/L. Levels of Hcy progressively increased with the use of Nutrineal: 28.1 +/- 6.2 micromol/L in week 2, 28.4 +/- 7.1 micromol/L in week 4, 29.1 +/- 7.6 micromol/L in week 6, 29.3 +/- 9.0 micromol/L in week 8, 27.5+/-9.7 micromol/L in week 10, and 30.3 +/- 8.2 micromol/L in week 12. CONCLUSIONS: Nutrineal might help to replenish daily protein loss, but it also increased formation of Hcy and, therefore, the potential risk of cardiovascular illness. Further studies will be needed to examine the effect of folic acid and vitamin B(12) supplementation in the rescue of that Hcy increase, and also a possible correlation with methylenetetrahydrofolate reductase gene polymorphism.

Effects of hemodialysis dose on anemia, hypertension, and nutrition.

There is good evidence that by improving dialysis adequacy, morbidity, and mortality of hemodialysis (HD) patients decrease. Dialysis adequacy has also been related to the better control of arterial blood pressure (BP), anemia and improvement of patients' nutritional status. This is a self-control study of 34 HD patients, (23 males, 11 females), aged 52.6 +/- 15.5 years, HD duration 55.9 +/- 61.2 months, referring to the effect of increasing delivered dialysis dose, over a two-year period, on their clinical and laboratory parameters. Delivered HD dose increased statistically significantly: Urea reduction ratio (URR) increased from 52 +/- 8 to 71 +/- 7% and Kt/V from 0.93 +/- 0.19 to 1.55 +/- 0.29 (p < 0.001). Hb increased statistically significantly from 10.4 +/- 1.7 to 11.0 +/- 1.3 g/dL (p < 0.05) while no difference has been noticed in weekly EPO dose. Both systolic and diastolic BP decreased statistically significantly (from 147 +/- 24 to 133 +/- 25mmHg and from 73 +/- 12 to 66 +/- 13 mmHg respectively, p = 0.001). Serum albumin increased from 4.3 +/- 0.4 to 4.6 +/- 0.3g/dL (p = 0.002) and nPCR from 0.93 +/- 0.16 to 1.20 +/- 0.17 (p < 0.001). We conclude that increasing dialysis dose results in both clinical and laboratory improvement regarding hypertension, nutritional status and control of HD patients' anemia.

Remarkable removal of beta-2-microglobulin by on-line hemodiafiltration.

UNLABELLED: Eight chronic, anuric hemodialysis patients were randomly treated with a high-flux polysulphone dialyzer (F80), using 6 different modes: conventional bicarbonate hemodialysis (HD), hemodiafiltration (HDF) with a replacement solution at 40, 60, 80 or 100 ml/min in postdilution and 80 ml/min in predilution. The differences in beta 2-microglobulin (beta 2M) reduction ratio and clearance were evaluated statistically by analysis of variance (ANOVA). Both studies revealed no significant difference between HD and HDF40 in postdilution, but an increasing significant difference from HDF60 to HDF100 in postdilution and with HDF80 in predilution. The mean reduction ratio ranged from 49.7 (HD) to 72.7% (HDF 100 ml/min), showing an overall statistically significant difference (p = 0.0000). For the clearance, the range was between 63.8 (HD) and 116.8 ml/min (HDF 100 ml/min) (p = 0.0000). beta 2M in the effluent dialysate with HDF 100 ml/min reached up to a mean of 258 mg/session. Concerning small molecules (BUN, creatinine and P), there was a statistically significant different clearance for creatinine and especially for P with HDF 100 ml/min. CONCLUSION: HDF with an on-line replacement solution at 100 ml/min and a high-flux and biocompatible polysulphone membrane represents a new tool for enhanced removal of beta 2M. Besides a significant increase in creatinine and especially in phosphorus clearance is noted.

High dialysate flow rate continuous arteriovenous hemodialysis: a new approach for the treatment of acute renal failure and tumor lysis syndrome.

A continuous dialysis technique such as continuous arteriovenous hemodialysis (CAVHD) could be an interesting alternative to frequent intermittent hemodialysis to treat acute renal failure (ARF) secondary to tumor lysis syndrome (TLS). However, because of massive release of intracellular solutes in TLS, CAVHD clearances need to be increased to treat this syndrome. Continuous arteriovenous hemodialysis using a high dialysate flow rate at 4 L/hr was assessed in TLS and ARF associated with severe hyperphosphatemia. A 0.6-m2 hollow-fiber polyacrylonitrile dialyzer (Multiflow 60; Hospal, St-Léonard, Québec, Canada) was used. Blood urea nitrogen and serum creatinine levels decreased, respectively, from 102.5 to 27.2 mg/dL and from 3.1 to 1.8 mg/dL during the 36 hours of treatment. Serum urate concentration was normal at the beginning of treatment (4.5 mg/dL) and decreased to 2.1 mg/dL by the end of CAVHD. Serum phosphorus decreased from 16.7 to 4.4 mg/dL after the 36 hours of treatment. The calcium x phosphorus product decreased from 111.1 to 42.1 by 28 hours and remained under 50 thereafter. Serum potassium was easily controlled with the addition of 2.5 mEq/L of KCl in dialysate and replacement solutions. No rebound increases in phosphorus or potassium were noted after cessation of therapy. Continuous arteriovenous hemodialysis clearances of urea, creatinine, phosphorus, and urate were measured at 2-hour intervals for the first 24 hours and at 4-hour intervals for the remaining 12 hours. They were 53.0 +/- 2.3 mL/min, 43.7 +/- 2.2 mL/min, 40.4 +/- 1.9 mL/min, and 39.3 +/- 1.9 mL/min (n = 15), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

High-dose calcium carbonate with stepwise reduction in dialysate calcium concentration: effective phosphate control and aluminium avoidance in haemodialysis patients.

To reduce potentially toxic aluminium exposure, the phosphate binding agent aluminium hydroxide was replaced by high-dose oral calcium carbonate in 15 haemodialysis patients. Stepwise reduction in dialysate calcium concentration (from 1.75 to 1.35 mmol/l and then to 1.05 mmol/l) was made when necessitated by hypercalcaemia. After 6 months, the mean daily dose of calcium carbonate was 62 mmol (range 25-150 mmol). This dose maintained good control of plasma phosphate (baseline, 1.34 +/- 0.32 mmol/l (mean +/- SD); 12 weeks, 1.30 +/- 0.22 mmol/l; 24 weeks, 1.51 +/- 0.31 mmol/l). Calcium x phosphate product did not rise significantly (baseline, 3.41; 12 weeks, 3.44; 24 weeks, 4.02). Apart from a transient early increase, ionised calcium did not change significantly (baseline, 1.23 +/- 0.10 mmol/l; 12 weeks, 1.24 +/- 0.10 mmol/l). Intact (1-84) parathyroid hormone concentration decreased from 241 pg/ml to 116 pg/ml (median values, P less than 0.05) after 12 weeks. This simple and well-tolerated regimen almost completely eliminated oral aluminium exposure, effectively controlled plasma phosphate and calcium concentrations, and reduced hyperparathyroidism.