Cost-effectiveness analysis of dyevert™ Power XT in patients with chronic kidney disease undergoing percutaneous coronary intervention procedures in Spain.

OBJECTIVE: To assess the efficiency of Dyevert™ Power XT compared to the standard clinical practice when used for percutaneous coronary interventions (PCI). METHODS: A Markov model was developed to estimate, over 3-month cycles and a lifetime time horizon, the cumulative costs and health outcomes (life years gained [LYG] and quality-adjusted life years [QALY]) in a hypothetical cohort of 1,000 patients with chronic kidney disease (CKD) 3b-4 and an average age of 72 years. The incidence of contrast-induced acute kidney injury for these patients is 18.89% in routine practice and 7.78% with Dyevert. QALYs were estimated by applying utilities by health state. Transitions between states and utilities were obtained from the literature. Overall all-cause and state-specific mortality were considered. The total cost (€2,022) estimated with the National Health System perspective included cost of the procedure and of CKD management. The parameters were validated by a panel of experts. A discount rate (3% per year) was applied to costs and outcomes. RESULTS: The use of Dyevert yielded more health benefits (34.60 LYG and 5.69 QALYs) compared to the current standard practice (33.11 LYG and 5.38 QALYs). Lifetime cost accumulated at the end of the simulation resulted €30,211/patient with Dyevert and €33,895/patient with current standard clinical practice. CONCLUSIONS: The use of Dyevert™ Power XT resulted dominant option, due to its higher effectiveness and lower cost as compared to standard clinical practice and, therefore, a preferred option in patients with CKD stages 3b-4 undergoing PCI in Spain.

Prophylaxis against postcontrast acute kidney injury (PC-AKI): updates in the ESUR guidelines 10.0 and critical review. / Profilaxis de la lesión renal aguda poscontraste (LRA-PC). Actualización según la guía clínica ESUR 10.0 y revisión crítica.

The European Society of Urogenital Radiology (ESUR) updated its guidelines for prophylaxis against postcontrast acute kidney injury (PC-AKI) in 2018 (ESUR 10.0). These guidelines drastically reduce the indications for prophylaxis against PC-AKI after iodine-based contrast administration, lowering the cutoff for administering prophylaxis to glomerular filtration rates <30ml/min/1.73m2 and eliminating most of the prior risk factors. Moreover, in cases where prophylaxis is considered necessary, the periods of hydration are shorter than in the previous version. These guidelines have been approved by most radiological societies, although they have also been criticized for excessive relaxation regarding risk factors, especially by the nephrological community. In this article, we critically review the changes to the guidelines.

New oral anticoagulants in patients with chronic kidney disease. / Nuevos anticoagulantes orales en pacientes con enfermedad renal crónica.

Patients with chronic kidney disease (CKD) develop bleeding and thrombotic tendencies, so the indication of anticoagulation at the onset of atrial fibrillation (AF) is complex. AF is the most common chronic cardiac arrhythmia, and thromboembolism and ischemic stroke in particular are major complications. In recent years, new oral anticoagulant drugs have been developed, and they have shown superiority over the classical AVK in preventing stroke, systemic embolism and bleeding risk, constituting an effective alternative to those resources.

Compliance with mineral metabolism targets in haemodialysis patients: moving backwards?

BACKGROUND: To standardize therapy and improve the clinical outcome for chronic haemodialysis (HD) patients, guidelines have been developed for mineral metabolism management. We evaluated compliance with different mineral metabolism guidelines. METHODS: 2,951 chronic HD patients from 61 dialysis centres in Spain were studied. Mineral metabolism management data from a 1-year period were analysed according to KDOQI, KDIGO, and Spanish guidelines. RESULTS: Only 1% (KDOQI), 6% (KDIGO) and 11% (Spanish guidelines) of patients continuously achieved total calcium (Ca), phosphate (P) and parathyroid hormone (PTH) target-range values during the year with higher percentages if we considered the 1-year average. The yearly Ca, P and iPTH average accomplished Spanish guidelines with different percentage among centres: CA 62-100%, P 59-91%, PTH 61-89%, and 28-77% considering all three targets together. The KDIGO guidelines recommend similar percentages except for P (33-77%). No differences were found related to eKt/V, online haemodiafiltration/HD, weight, body mass index, or dialysis vintage. They were only related to age, blood flow, effective treatment time, and dialysate calcium but without relevant clinical differences. Patients outside the target ranges generated significantly higher treatment costs. CONCLUSIONS: Compliance with mineral metabolism targets in HD patients was poor and showed a wide variation between treatment centres.

Economic impact of vitamin D treatment on chronic kidney disease patients.

During recent years, increasing recognition has been given to the endocrine action that vitamin D has on the extraskeletal system, and its deep involvement in CKD. This has meant that many vitamin D compounds (both nutritional and active) have been made available, with an important cost reduction. This review looks at the evidence available regarding the usefulness of different types of vitamin D (nutritional and active) for patients with stage 3-5 CKD and those undergoing dialysis. Emphasis is given to its usefulness to control hyperparathyroidism and its impact on morbidity and mortality. We also analysed pharmacoeconomic studies that have been published which compare active vitamin D metabolites. From this review, we are able to conclude that there is still not enough scientific evidence to be able to prefer one active vitamin D over another. In the meantime, doctors should follow the recommendations given in clinical practice guidelines, always taking into account their personal experience with patients. Furthermore, they must consider the economic impact that their treatment decisions may have.

Under-recognized renal insufficiency in hospitalized patients: implications for care.

BACKGROUND: The consequences of undetected low glomerular filtration rate (GFR) are important in hospitalized patients who receive potentially nephrotoxic drugs or undergo major surgery. This study estimated the prevalence of estimated GFR (eGFR) <60mL/min/1.73m(2) in hospitalized patients. METHODS: This cross-sectional descriptive study included 14,658 adults hospitalized at 10 centers in Spain. Serum samples were analyzed for hemoglobin, creatinine, albumin and urea nitrogen. eGFR was estimated using Modification of Diet in Renal Disease (MDRD) 4 or MDRD IDMS, and MDRD 6 when serum albumin and BUN were included (n=8611). Individuals were classified as having GFR>or=60mL/min/1.73m(2), stages 3, 4 and 5 (GFR 30-59, 15-29 and <15mL/min/1.73m(2), respectively). Additionally, stages 3a and 3b (GFR 45-59 and 30-44mL/min/1.73m(2), respectively) were assessed. RESULTS: MDRD 4 eGFR showed that 28.3% of patients had renal insufficiency stages 3-5 and 14.2% had stages 3b, 4 or 5, which represents important-severe renal deterioration. Forty-three percent of patients with stages 3-5 had hemoglobin or=60mL/min/1.73m(2). A good correlation was observed between eGFR MDRD 4 and MDRD 6. CONCLUSIONS: A high percentage of hospitalized patients in Spain have deteriorated renal function stages 3-5. Using eGFR equations to assess eGFR could identify more hospitalized patients with renal insufficiency, potentially leading to improved care.

[The Bahía 2008 Study: hydration barometer in the Spanish population]. / Estudio Bahía 2008: barómetro de la hidratación de la población española.

BACKGROUND: Vital functions require a balance between the loss and ingestion of liquids. There are no studies about hydration on Spanish population. MATERIAL AND METHODS: 6,508 questionnaires were applied to a randomly selected Spanish population, together with a 24-hour recall in order to measure liquid consumption and variables related to it. RESULTS: The average consumption of liquids was 2,089.5 +/- 771.4 and 6.05 drinking times/day. 3,423 persons (52.6% of the studied people, CI 95% 51.3%-53.8%) were well-hydrated when considering their individual intake. The frequency and volume of drinking decreased with age. 61% (CI 95% 58.64%-64.01%) of the population older than 65 years were badly hydrated. The greatest bottled water consumption corresponded to the youngest population (18-29 years). The greater the physical activity, the greater the beverages consumption (1,987.6 +/- 705.5 ml vs 2,345.8 +/- 928.1 ml, low vs. intense physical activity, respectively). With regard to the intake frequency and volume, mineral and tap water were the most consumed. Those who drank mineral water exceeded the 2 l-recommendation in order to maintain a good hydration status. 59.8% (CI 95% 57.83%-61.76%) of those who preferred mineral water drank more than 2 l/day and drank more times/day and in greater amounts. There was a greater frequency and amount of beverage consumption when people lived in the same house, and particularly more in houses where children were living (2,197.4 +/- 767.8 ml vs 2,055.7 +/- 769.86 ml and 6.4 +/- 2.2 times vs 5.9 +/- 1,9 times, in homes with or without children, respectively). Bottled water was preferred at home (79.07%) and at work (15.61%). CONCLUSIONS: Only half of the Spanish population is well hydrated. Sixty-one percent of people over the age of 65 years were poorly hydrated, consequence it is imperative to promote its consumption.

[Evolution of the darbepoetin alpha resistance index in patients on dialysis who change from weekly to fortnightly treatments in clinical practice]. / Evolución del índice de resistencia a darbepoetina alfa en pacientes dializados que cambian de administración semanal a quincenal en la práctica clínica.

BACKGROUND: Darbepoetin alpha (DA) administered every-other-week (Q2W) is efficacious and safe for the treatment of anaemia in patients undergoing dialysis. There are no data available regarding the evolution of erythropoietic resistance index (ERI) after conversion from weekly (QW) to Q2W administration of DA in clinical practice. MATERIAL AND METHODS: Multicenter, observational, retrospective, 16-weeks study, which included stable patients undergoing dialysis who were converted from DA QW to DA Q2W in clinical practice. Conversion was done according to product specifications (duplicating QW dose). The ERI to DA was calculated by dividing the weekly DA dose per kilogram of weight (microg/wk.kg)*200 by the Hb level (g/dL). ERI evolution with time was evaluated by multivariate repeated measures ANOVA, adjusting for significant covariates. RESULTS: A total of 202 patients were included (137 patients undergoing haemodialysis [HD], intravenous (IV) DA, and 65 patients receiving peritoneal dialysis [PD], subcutaneous DA). Mean (SD) age was 66 (17) years; 61% of patients were men. Large intercentre variability was observed for the ERI at conversion time (coefficient of variation of 88%, p < 0.001 for differences between centres). In the univariate analysis, predictor factors for high baseline ERI were low albumin level (r = -0.29; p =0.001), HD (mean ERI of 9.3 [8.4] vs 6.8 [4.6] for PD; p = 0.005), or previous cardiovascular disease (9.9 [8.7] vs 7.4 [6.3] for patients without history; p =0.025). During the follow up, the ERI was slightly increased in HD patients (9.3 [8.4] at conversion vs 11.1 [7.3] at 16 weeks; p < 0.05), and remained stable in PD patients (6.8 [4.6] vs 6.7 [4.0], respectively; NS). In the multivariate analysis, there were no significant differences in ERI during the 16 weeks post-conversion after adjusting for albumin levels and centre (adjusted baseline mean [95% CI] of 10.0 [8.7-11.4] vs 10.5 [9.3-11.8] at 16 weeks, adjusted change of +0.5 [-0.67; 1.67]; NS). After 16 weeks, only 7 patients (3.5%) had discontinued Q2W administration. CONCLUSIONS: Extension from weekly to once every other-week darbepoetin alpha allows to simplify anaemia treatment without increasing the resistance index, regardless of dialysis type. The multivariate analysis shows that, after adjusting by center and inflammation/nutritional status, there were no changes in the response to darbepoetin alpha during the first 16 weeks after conversion in clinical practice.

The phenomenon of hemoglobin variability with erythropoiesis stimulating agents in renal transplant patients.

Treatment with erythropoiesis-stimulating agents (ESA) is often associated with fluctuation in hemoglobin (Hb) levels that has been considered a factor that influences morbidity/mortality in hemodialysis patients. Our aim was to describe the hemoglobin variability during ESA treatment and to study associated factors in kidney transplants. Hb variability (defined as fluctuations of Hb +/- 1.5 g/dl) was assessed in 85 renal transplant patients treated with ESA for at least 3 months and with a minimum of 6 Hb measurements along 1 year. 58% of patients experienced Hb variability during follow-up. Although 71.3% of patients maintained Hb levels greater than 11 g/dl along the whole follow-up, only 3% of patients maintained stable Hb levels within the target range all the time (11 - 13 g/dl). By multivariate analysis, clinical factors associated with variability were changes in ESA dose (RR 2.92, p = 0.04), infectious events with hospitalization (RR 1.95, p = 0.03) and the use of sirolimus (RR 1.1, p < 0.05). Excluding dose changes and hospitalization in the analysis variability was an independent predictor of graft function deterioration. In conclusion, Hb variability is common in renal transplants treated with ESA. Only few patients maintained Hb levels in the therapeutic range (11 - 13 g/dl). Dose changes, inflammatory status and graft function deterioration are the determining factors.

Bone metabolism according to chronic kidney disease stages in patients undergoing kidney transplantation: a 5-year database analysis.

INTRODUCTION: While kidney transplantation successfully reverses many complications of uremia that are not corrected with dialysis therapy, elevated parathyroid hormone (PTH) levels and other alterations of mineral metabolism persist in transplant recipients. PATIENTS AND METHODS: A single-center cohort retrospective database analysis was performed of 497 consecutive adult patients who underwent first kidney transplantation between 1994 and 2004. At 1- and 5-year follow-up, a descriptive analysis was performed of mineral metabolism parameters of chronic kidney disease stage according to NKF KDOQI (National Kidney Foundation Kidney Disease Outcomes Quality Initiative) in patients with a functional graft at 1 year. Glomerular filtration rate was estimated using the abbreviated MDRD (Modification of Diet in Renal Disease) equation. RESULTS: Most of the transplants (99.2%) were from cadaveric donors. Mean (SD) patient age was 47.7 (13.3) years, and 69% of patients were men. The causes of chronic kidney disease were glomerular (35.4%), congenital (15.4%), systemic (14.1%), vascular (11.3%), interstitial (10.1%), and other (<1%). The percentage of patients in each stage of chronic kidney disease with calcium levels less than 8.5 mg/dL, phosphorus greater than 4.5 mg/dL, and PTHi greater than 150 pg/mL increased as graft function declined. Six posttransplantation parathyroidectomies were performed. Only 130 patients received secondary hyperparathyroidism treatment within 5 years after transplantation: calcium carbonate, 36.9%; calcium acetate, 1.5%; calcium carbonate plus cholecalciferol, 21%; calcitriol, 71%; and calcifediol, 0.8%. CONCLUSIONS: The prevalence of hypocalcemia, hyperphosphatemia, and elevated PTH level increased with chronic kidney disease stage. Classification of renal transplant recipients by KDOQI stage may enable clinicians to identify patients at increased risk and to target appropriate therapy to improve outcome. There is an opportunity for enhanced management of secondary hyperparathyroidism in these patients.

Chronic renal disease in renal transplant patients: management of cardiovascular risk factors.

Kidney transplantation is the treatment of choice for patients with end-stage renal disease. Despite improvements in short-term patient and graft outcomes, there has been no major improvement in long-term outcomes. The aim of this study was to determine the prevalence of cardiovascular risk factors, such as hypertension, dyslipidemia, diabetes, chronic kidney disease, and obesity, and the impact of their control among 526 stable renal transplant recipients according to the guidelines in the general population. Mean blood pressure was 133 +/- 16/81 +/- 9 mm Hg. The proportion of patients on antihypertensive therapy was 75%, and on ACE inhibitors or angiotensin II receptor blockers, 26%. The mean cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglycerides were 195 +/- 41, 115 +/- 32, 51 +/- 17, and 137 +/- 75 mg/dL, respectively. The proportion of patients on statin treatment was 49.7%, and those with body mass indices between 25 and 30, 30 and 35, and >35 kg/m(2) were 35%, 15%, and 4%. We observed a high prevalence of chronic kidney disease, hypertension, dyslipidemia, and obesity among renal transplant patients. Suboptimal control was frequent and control of some of these complications was far below targets established for nontransplant patients despite progressive intensification of therapy with functional graft decline. The findings of this study may have an impact on the management of renal transplant recipients.

[Changes in the pre-transplant bone-mineral metabolism do not affect the initial progress of the renal graft]. / Las alteraciones del metabolismo óseo-mineral pretrasplante no influyen en la evolución inicial del injerto renal.

BACKGROUND: Abnormalities in serum calcium, phosphate, and Parathyroid Hormone (PTH) concentrations are common in patients with chronic kidney disease and have been associated with increased morbidity and mortality. One of the most common problems in the first weeks after renal transplantation is Delayed Graft Function (DGF). There are several well-known risk factors for DGF development, but the role of calcium phosphate-PTH homeostasis as a risk factor for early graft dysfunction is controversial. This issue was addressed in the current study. METHODS: Pretransplant PTH, calcium and phosphate values were gathered in 449 patients that received a renal transplant in our center between 1994 and 2007. Other variables expected to influence the risk for delayed graft function were included from the clinical charts. RESULTS: The incidence of DGF was 27.3%. DGF development was significantly associated with recipient age, type and need of renal replacement therapy, peak panel reactive antibodies, transfusion number and donor age. There were no significant differences in the mean pretransplant values of calcium (9.4 +/- 1.0 vs. 9.5 +/- 0.9 mg/dl, p = 0.667), phosphate (5.7 +/- 1.8 vs. 5.5 +/- 1.5 mg/dl, p = 0.457), calcium-phosphate product (53.5 +/- 17.2 vs. 51.8 +/- 14.6 mg(2)/dl(2), p = 0.413) and PTH (315 +/- 312 vs. 340 +/- 350 pg/ml, p = 0.530) between patients with and without DGF. CONCLUSIONS: In our study population pretransplant serum PTH, calcium and phosphorus levels have no influence on the risk for DGF.

[Acetate-free on-line PHF: how to improve hyperacetatemia and haemodynamic tolerance]. / PHF on-line sin acetato: cómo mejorar la hiperacetatemia y la tolerancia hemodinámica.

SUMMARY BACKGROUND: The small quantity of acetate present in the dialysis fluid exposes patient's blood to an acetate concentration 30-40 times the physiological levels. This amount is even greater in hemodiafiltration on-line. Our purpose was to evaluate the clinical-analytical effects using three different dialysis techniques in the same patient. METHODS: 35 patients on hemodialysis were included. All patients were treated with conventional bicarbonate dialysate for 3 months, after randomization were switched to first be treated with PHF online with standard bicarbonate dialysate for 6 months and then switched to PHF on-line acetate-free dialysate for the other 6 months or to invert the two last periods. Blood samples were drawn monthly throughout the study and clinical data were obtained. RESULTS: Postdialysis blood acetate levels were higher in patients treated with conventional bicarbonate dialysate with respect to the period of PHF with free-acetate dialysate. Moreover, the percentage of patients with postdialysis blood acetate levels in the pathologic range was higher in patients treated with conventional bicarbonate dialysate respect to PHF on-line acetate-free dialysate period (61% vs. 30%). Serum concentrations of chloride postdialysis were higher and serum concentrations of bicarbonate pre and posthemodialysis were lower in the PHF free-acetate period. The incidence of hypotensive episodes was significantly lower in the PHF on-line with conventional dialysate. CONCLUSIONS: PHF on-line with free-acetate dialysate allows that most of patients finished hemodialysis with blood acetate levels in the physiologic ranges. PHF on-line is a predilutional hemodiafiltration treatment with better tolerance than hemodialysis with standard bicarbonate dialysate.

Las alteraciones del metabolismo óseo-mineral pretrasplante no influyen en la evolución inicial del injerto renal / No disponible

Antecedentes: el Retraso en la Función del Injerto (RFI) es uno delos problemas más frecuentes en las primeras semanas del trasplante renal, afectando a su evolución. Conocer los factores de riesgo de RFI puede ayudar a reducir su incidencia. Las alteraciones en los niveles séricos de calcio, fósforo y Hormona Paratiroidea (HPT) son muy frecuentes en los pacientes en lista de espera de trasplante y podrían favorecer la aparición de RFI. Sin embargo, diversos estudios que han analizado la relación entre los niveles pretrasplante de calcio, fósforo y HPT y el desarrollo de RFI han obtenido resultados dispares que no permiten confirmar ni descartar que influyan en el mismo. Métodos: estudiamos los valores pretrasplante de calcio, fósforo y HPT en 449 pacientes trasplantados renales realizados entre 1994 y 2007. Se definió RFI en aquellos pacientes que precisaron diálisis durante la primera semana postrasplante. De las historias clínicas se recogieron los datos clínicos y analíticos relacionados con RFI. Resultados: un 27,3%presentó RFI. Los factores significativos de riesgo para desarrollar RFI fueron la edad del receptor, el tipo y la necesidad de tratamiento sustitutivo renal, el título de anticuerpos anti-HLA máximos, el número de trasfusiones pretrasplante y la edad del donante. No detectamos diferencias significativas en los valores medios de calcio (9,4 ± 1,0 vs. 9,5 ± 0,9 mg/dl, p = 0,667), fósforo(5,7 ± 1,8 vs. 5,5 ± 1,5 mg/dl, p = 0,457), producto fosfocálcico (53,5± 17,2 vs. 51,8 ± 14,6 mg2/dl2, p = 0,413) y HPTi (315 ± 312 vs. 340± 350 pg/ml, p = 0,530) en los pacientes con y sin RFI. Conclusiones: en nuestro estudio, los parámetros séricos pretrasplante del metabolismo óseo-mineral no favorecen el desarrollo de RFI (AU)

Background: abnormalities in serum calcium, phosphate, and Parathyroid Hormone (HPT) concentrations are common in patients with chronic kidney disease and have been associated with increased morbidity and mortality. One of the most common problems in the first weeks after renal transplantation is Delayed Graft Function (DGF). There are several well-known risk factors for DGF development, but the role of calciumphosphate-HPT homeostasis as a risk factor for early graft dysfunction is controversial. This issue was addressed in the current study. Methods: Pretransplant HPT, calcium and phosphate values were gathered in 449patients that received a renal transplant in our center between 1994 and 2007. Other variables expected to influence the risk for delayed graft function wereincluded from the clinical charts. Results: The incidence of DGF was 27.3%. DGF development was significantly associated with recipient age, type and need of renal replacement therapy, peak panel reactive antibodies, transfusion number and donor age. There were no significant differences in the mean pretransplant values of calcium (9.4 ± 1.0 vs. 9.5 ± 0.9 mg/dl, p = 0.667),phosphate (5.7 ± 1.8 vs. 5.5 ± 1.5 mg/dl, p = 0.457),calcium-phosphate product (53.5 ± 17.2 vs. 51.8 ± 14.6mg2/dl2, p = 0.413) and HPT (315 ± 312 vs. 340 ± 350pg/ml, p = 0.530) between patients with and without DGF. Conclusions: In our study population pretransplant serum HPT, calcium and phosphorus levels have no influence on the risk for DGF (AU)

PHF on-line sin acetato: cómo mejorar la hiperacetatemia y la tolerancia hemodinámica / No disponible

Antecedentes: la presencia de acético en el Líquido de Diálisis (LD) expone al paciente a una concentración de acetato 30-40 veces superior a la normal. Dicha exposición aumenta en técnicas de Hemodiafiltración (HDF) online. El objetivo de dicho estudio fue evaluar los cambios clínico-analíticos al usar tres técnicas de Hemodiálisis(HD) diferentes. Métodos: se reclutaron 35 pacientes en HD estable. Se dializaron tres meses con HD convencional y luego fueron aleatorizados para pasar a una técnica de PHF on-line con concentrado convencional seis meses, y después pasaron a PHF on-line sin acetato otros seis meses. El otro grupo invertía estos dos períodos. Se obtuvieron análisis de sangre y datos clínicos de HD. Resultados: las medias de los acetatos posdiálisis fueron significativamente superiores durante los períodos de tratamiento con acético respecto al período sin acetato. El porcentaje de valores patológicos de acetato posdiálisis fue significativamente superior durante los períodos de tratamiento con acético (61 respecto al 30%). Las concentraciones de cloro pos-HD fueron superiores y las de bicarbonato pre y pos-HD fueron menores durante el período sin acético. El número de hipotensiones fue significativamente inferior en el período de PHF on-line con LD estándar respecto a los otros períodos. Conclusiones: la técnica de PHF on-line sin acetato disminuye la exposición a concentraciones elevadas de acetato y consigue que la mayoría de pacientes termine la HD con una acetatemia en el rango fisiológico. La PHF on-line es un tratamiento de HDF predilucional con mejor tolerancia que la HD estándar con bicarbonato (AU)

Summary Background: the small quantity of acetate present in the dialysis fluid exposes patient’s blood to an acetate concentration 30-40 times the physiological levels. This amountis even greater in hemodiafiltration on-line. Our purpose was to evaluate the clinical-analytical effects using three different dialysis techniques in the same patient. Methods: 35 patients on hemodialysis were included. All patients were treated with conventional bicarbonate dialysate for 3 months, after randomization were switched to first be treated with PHF online with standard bicarbonate dialysate for 6 months and then switched to PHF on-line acetate-free dialysate for the other 6months or to invert the two last periods. Blood samples were drawn monthly throughout the study and clinical data were obtained. Results: Posdialysis blood acetate levels were higher in patients treated with conventional bicarbonate dialysate with respect to the period of PHF with free-acetate dialysate. Moreover, the percentage of patients with posdialysis blood acetate levels in the pathologic range was higher in patients treated with conventional bicarbonate dialysate respect to PHF on-line acetate-free dialysate period (61% vs. 30%). Serum concentrations of chloride posdialysis were higher and serum concentrations of bicarbonate pre and poshemodialysis were lower in the PHF free-acetate period. The incidence of hypotensive episodes was significantly lower in the PHF on-line with conventional dialysate. Conclusions: PHF on-line with free-acetate dialysate allows that most of patients finished hemodialysis with blood acetate levels in the physiologic ranges. PHF on-line is a predilutional hemodiafiltration treatment with better tolerance than hemodialysis with standard bicarbonate dialysate (AU)