Short Dialysis Research Articles

Replacement of acetate with citrate in dialysis fluid: a randomized clinical trial of short term safety and fluid biocompatibility

BackgroundThe majority of bicarbonate based dialysis fluids are acidified with acetate. Citrate, a well known anticoagulant and antioxidant, has been suggested as a biocompatible alternative. The objective of this study was to evaluate short term safety and biocompatibility of a citrate containing acetate-free dialysis fluid.MethodsTwenty four (24) patients on maintenance dialysis three times per week, 13 on on-line hemodiafiltration (HDF) and 11 on hemodialysis (HD), were randomly assigned to start with either citrate dialysis fluid (1 mM citrate, 1.5 mM calcium) or control fluid (3 mM acetate, 1.5 mM calcium) in an open-labeled cross-over trial (6 + 6 weeks with 8 treatments wash-out in between). Twenty (20) patients, 11 on HDF and 9 on HD were included in the analyses. Main objective was short term safety assessed by acid–base status, plasma ionized calcium and parathyroid hormone (PTH). In addition, biocompatibility was assessed by markers of inflammation (pentraxin 3 (PTX-3), CRP, IL-6, TNF-α and IL-1β) and thrombogenicity (activated partial thromboplastin time (APTT) and visual clotting scores).ResultsNo differences dependent on randomization order or treatment mode (HD vs. HDF) were detected. Citrate in the dialysis fluid reduced the intra-dialytic shift in pH (+0.04 week 6 vs. +0.06 week 0, p = 0.046) and base excess (+3.9 mM week 6 vs. +5.6 mM week 0, p = 0.006) over the study period. Using the same calcium concentration (1.5 mM), citrate dialysis fluid resulted in lower post-dialysis plasma ionized calcium level (1.10 mM vs. 1.27 mM for control, p < 0.0001) and higher post-dialysis PTH level (28.8 pM vs. 14.7 pM for control, p < 0.0001) while pre-dialysis levels were unaffected. Citrate reduced intra-dialytic induction of PTX-3 (+1.1 ng/ml vs. +1.4 ng/ml for control, p = 0.04) but had no effect on other markers of inflammation or oxidative stress. Citrate reduced visual clotting in the arterial air chamber during HDF (1.0 vs. 1.8 for control, p = 0.03) and caused an intra-dialytic increase in APTT (+6.8 s, p = 0.003) without affecting post-dialysis values compared to control.ConclusionsDuring this small short term study citrate dialysis fluid was apparently safe to use in HD and on-line HDF treatments. Indications of reduced treatment-induced inflammation and thrombogenicity suggest citrate as a biocompatible alternative to acetate in dialysis fluid. However, the results need to be confirmed in long term studies.Trial registrationISRCTN: ISRCTN28536511

A time‐to‐event model for acute rejections in paediatric renal transplant recipients treated with ciclosporin A

Ciclosporin A (CsA) dosing in immunosuppression after paediatric kidney transplantation remains challenging, and appropriate target CsA exposures (AUCs) are controversial. This study aimed to develop a time-to-first-acute rejection (AR) model and to explore predictive factors for therapy outcome. Patient records at the Children's Hospital in Helsinki, Finland, were analysed. A parametric survival model in NONMEM was used to describe the time to first AR. The influences of AUC and other covariates were explored using stepwise covariate modelling, bootstrap-stepwise covariate modelling and cross-validated stepwise covariate modelling. The clinical relevance of the effects was assessed with the time at which 90% of the patients were AR free (t90). Data from 87 patients (0.7-19.8 years old, 54 experiencing an AR) were analysed. The baseline hazard was described with a function changing in steps over time. No statistically significant covariate effects were identified, a finding substantiated by all methods used. Thus, within the observed AUC range (90% interval 1.13-8.40 h mg l⁻¹), a rise in AUC was not found to increase protection from AR. Dialysis time, sex and baseline weight were potential covariates, but the predicted clinical relevance of their effects was low. For the strongest covariate, dialysis time, median t90 was 5.8 days (90% confidence interval 5.1-6.8) for long dialysis times (90th percentile) and 7.4 days (6.4-11.7) for short dialysis times (10th percentile). A survival model with discrete time-varying hazards described the data. Within the observed range, AUC was not identified as a covariate. This feedback on clinical practice may help to avoid unnecessarily high CsA dosing in children.

Outcome of Urgent Hemodialysis in Chronic Kidney Disease in a Rural Tertiary Care Hospital

Chronic kidney disease is a worldwide public health problem with an increasing incidence and prevalence. Outcomes of chronic kidney disease include not only complications of decreased kidney function and cardiovascular disease but also end stage renal failure causing increased morbidity and mortality. The development of acute but serious uremic complications in advanced kidney disease may put the patient's life at risk requiring immediate dialysis. The objective of this study was to find out the outcomes of urgent hemodialysis in advanced kidney disease, the minimum number of hemodialysis required for satisfactory clinical improvement, and to detect uremic emergencies associated with those patients. Twenty two patients with end stage renal failure admitted in a rural tertiary care private hospital of Bangladesh for emergency and short term dialysis were included in this study. For each patient hemodialysis was done at one day interval three times in a week in a dialysis unit. Results show that two sessions of hemodialysis produced 72 % and three sessions, almost 100% clinical recovery at satisfactory level. Urgent hemodialysis was found to be life saving in observed uremic emergencies like acute pulmonary edema, cerebral encephalopathy, metabolic acidosis, hyperkalemia, gross fluid overload and pericardial effusion. Dialysis therapy ameliorates many of the clinical manifestations of renal failure and postpones otherwise imminent death and for these logical reasons it is recommended that dialysis should not be delayed in uremic emergencies for the best interest of clinical outcomes. KYAMC Journal Vol. 3, No.-2, January 2013, Page 277-281 DOI: http://dx.doi.org/10.3329/kyamcj.v3i2.15167

Renal Transplantation Is Associated with Improved Clinical Outcomes in Nephrogenic Systemic Fibrosis

Nephrogenic systemic fibrosis is a debilitating disorder seen in chronic kidney disease patients and is characterized by stiffening of the joints and thickening of the skin. Treatment options are limited, but some patients have had an improvement of their clinical symptoms after renal transplantation and the use of immunosuppression. Although there is a variable response to renal transplantation, it is currently unknown what factors promote a favorable outcome. Our objective was to evaluate if the response to renal transplantation was superior to other treatment modalities and to determine which characteristics allowed for a positive response to occur. We retrieved the data from the literature of 298 reported patients, compared the response to renal transplantation and to other treatments, and analyzed their characteristics. We found that more patients had a higher response to renal transplantation, as determined by softening of the skin and improved joint mobility, and among those that did respond, they had a shorter dialysis vintage. We suggest that if renal transplantation is to be considered as a treatment modality, it should be initiated at the earliest possible in the course of the disease to achieve maximum clinical benefit.

Intracellular dialysis disrupts Zn2+ dynamics and enables selective detection of Zn2+ influx in brain slice preparations

We examined the impact of intracellular dialysis on fluorescence detection of neuronal intracellular Zn(2+) accumulation. Comparison between two dialysis conditions (standard; 20min, brief; 2min) by standard whole-cell clamp revealed a high vulnerability of intracellular Zn(2+) buffers to intracellular dialysis. Thus, low concentrations of zinc-pyrithione generated robust responses in neurons with standard dialysis, but signals were smaller in neurons with short dialysis. Release from oxidation-sensitive Zn(2+) pools was reduced by standard dialysis, when compared with responses in neurons with brief dialysis. The dialysis effects were partly reversed by inclusion of recombinant metallothionein-3 in the dialysis solution. These findings suggested that extensive dialysis could be exploited for selective detection of transmembrane Zn(2+) influx. Different dialysis conditions were then used to probe responses to synaptic stimulation. Under standard dialysis conditions, synaptic stimuli generated significant FluoZin-3 signals in wild-type (WT) preparations, but responses were almost absent in preparations lacking vesicular Zn(2+) (ZnT3-KO). In contrast, under brief dialysis conditions, intracellular Zn(2+) transients were very similar in WT and ZnT3-KO preparations. This suggests that both intracellular release and transmembrane flux can contribute to intracellular Zn(2+) accumulation after synaptic stimulation. These results demonstrate significant confounds and potential use of intracellular dialysis to investigate intracellular Zn(2+) accumulation mechanisms.

Thrice-weekly nocturnal hemodialysis: the overlooked alternative to improve patient outcomes

Hemodialysis (HD) therapy for patients suffering from end-stage renal disease (ESRD) has been a major breakthrough in medicine during the twentieth century. Empirically, the conventional treatment is prescribed as 3-4.5 h of dialysis, three times a week. However, this prescription is being questioned because of poor patient outcomes including a persistently high death rate. Over the past 30 years, K(t)/V(urea) has been recognized as the predominant marker of dialysis adequacy. However, other important markers of 'adequate' dialysis are increasingly being recognized, including fluid and phosphate balance, and middle molecule removal. Conventional HD therapy, as it exists today, is limited in its scope to make a significant impact on these markers. Consequently, there is an active debate on novel HD strategies to improve patient outcomes. Recently, two randomized controlled trials (RCTs) have highlighted potential benefits for patients with two such strategies, short or long nocturnal daily dialysis. These two trials did, however, highlight the difficulty in recruiting patients for such studies. A higher rate of blood access-related complications was also reported. Such novel strategies are also limited in their application by a higher economic burden and logistical difficulties. On the other hand, the thrice-weekly nocturnal HD prescription has been associated with excellent clinical results in observational reports published over recent years. Several non-randomized controlled studies support the clinical benefits of this approach. This prescription may overcome the limitations of daily dialysis and offer a potential for improving patient outcomes on HD. Even if the methodology of the latter studies may not be optimal, we underscore the point that this alternative dialysis prescription should be included in the current debate of novel dialysis strategies.

Con: Randomized controlled trials (RCT) have failed in the study of dialysis methods

All progress in dialysis methods was made in research presented in case reports, case-control studies and other observational studies. On the contrary, randomized controlled trials (RCTs) did not bring any valuable results. Comparison of the value of peritoneal dialysis and hemodialysis (HD) in RCTs was not completed because of recruitment problems. Four RCTs in HD did not provide any useful data. The worst example was the National Cooperative Dialysis Study, which committed a Type II statistical error rejecting the time of dialysis as an important factor determining the quality of dialysis. This study also provided the basis for the establishment of the Kt/V index as a measure of dialysis adequacy. This index was accepted by the HD community, having been established in a sacrosanct RCT, led to short dialysis, and possibly higher mortality in the USA. The second trial (the HEMO study) committed a Type III statistical error asking the wrong question and did not bring any valuable results, but at least it did not lead to deterioration of dialysis outcomes in the USA. The third, the Frequent Hemodialysis Network Trial Group, did not bring forth any valuable results, but at least confirmed what was already known. The fourth, the Frequent Hemodialysis Network Nocturnal Trial, committed a Type II statistical error because of tremendous recruitment problems leading to an inadequate number of subjects. Moreover, the study methodology was absolutely unreliable.

A Simple, Green Synthesis of Photochromic, Monoclinic Tungsten Oxide Fiber

The fiber shaped monoclinic tungsten oxides with high preferential orientation has been synthesized by dialysis and aging treatment at room temperature, of the white precipitates prepared from HCl acidified (NH4)10W12O41 solution. The microstructure evolution of the above tungsten oxide was studied by SEM. The morphology of the powder changed from irregularity to shuttle plate-like during short time dialysis in pure water, and the butterfly shape was obtained after long time treatment. It was found that the nano-particles were rearranged to form nano-fibers on the surface of the butterfly shaped oxide as a function of aging time when the butterfly powder was kept in the original mother liquor. Compared to butterfly oxide, the morphology of fibers exhibited much improved thermal stability. The photochromic property of the tungsten oxide with different morphology was studied. The response time in color change after irradiated by the UV output of a 30 W mercury lamp is 20 s in inert atmosphere and the recovery time in bleach is about 2 months.

HOME HAEMODIALYSIS DOSE: HOW MUCH OF A GOOD THING?

Home dialysis (peritoneal or haemodialysis) in any reasonable guise offers potential benefits compared with in-centre dialysis. Benefits may be overtly patient centred (independence, quality of life), outcome oriented (survival, resolution of left ventricular hypertrophy) or resource friendly (savings on staff costs). The priority placed on each of these areas is likely to vary from patient to patient, and possibly provider to provider. This is the one strength of home haemodialysis (HHD) rather than being viewed as a weakness, as it can offer different benefits to different people. Intuitively, more haemodialysis is better than less, and this is most realistically achieved at home. Indications are that both long nocturnal dialysis and short daily dialysis can offer real objective benefits. Critics argue correctly that there is a paucity of robust randomised controlled study data. The complexity of HHD regimens and practice and in-homogeneity of patients means such firm data are unlikely to be forthcoming. However, the positive reports both subjective and objective of patients dialysing at home, and results from the available research suggest that advantages may be seen purely with changing the location of dialysis to home, and independently with enhancing dialysis schedules. The logical conclusion is that patients undertaking haemodialysis at home should have at least the recommended minimum of four hours three times per week (or equivalent), preferably avoiding the long inter-dialytic interval, but beyond that rigid adherence to a schedule as dogma should be subjugated to patient choice and flexibility, albeit by prior agreement with supervising medical and nursing staff.

Alternatives to standard unfractionated heparin for pediatric hemodialysis treatments

Despite advances in biomaterials and dialyzer design, thrombin generation occurs in the dialysis circuit because of platelet and leukocyte activation. As such, anticoagulation is required by the majority of children for successful dialysis to prevent clotting in the venous air detector and the capillary dialyzer, particularly for small children with slower blood flow rates. For many years unfractionated heparin has been the standard anticoagulant of choice, but is now being challenged by low-molecular-weight heparins (LMWHs) because they are simple to administer and reliable, particularly as the cost differential has been eroded. Alternative, nonheparin anticoagulants are more frequently available, but are often restricted to special circumstances: patients at high risk of hemorrhage; heparin allergy; or heparin-induced thrombocytopenia. These nonheparin alternatives are significantly more expensive than heparins, and may add a degree of complexity, such as citrate, which is a regional anticoagulant, although citrate-containing dialysate may permit short anticoagulant-free dialysis sessions. Systemic anticoagulants required for immune-mediated, heparin-induced thrombocytopenia are expensive and either have short half-lives, and therefore require continuous infusions, or prolonged half-lives, which, although allowing simple bolus administration, increases the risk of drug accumulation, over-dosage and hemorrhage.

Factors Influencing Behavior of Taking Medicine in Elderly Patients Undergoing Hemodialysis

Purpose: The elderly are often faced with multiple diseases, in particular hemodialysis (HD) which requires many kinds of medication. This study examined the factors influencing the behavior of taking medicine in elderly patients undergoing HD. Subjects and Methods: The subjects comprised 70 outpatients > 65 years undergoing HD (48 male and 22 female). The mean age of the patients was 72.5 ± 4.4 years. The mean duration of dialysis history was 6.1 ± 5.2 years. We performed a questionnaire survey using Medication Assessment Tool, The Kidney Disease Quality of Life (QOL)-Short Form and Acceptance for Dialysis Instrument. Result: Two factors related to poor behavior of taking medicine: dialysis history < 2 years and poor acceptance of dialysis. The multiple regression analysis showed patient satisfaction (β = –0.329, p < 0.01) and symptoms/problems (β = –0.273, p<0.05) as significant independent variables relating to behavior of taking medicine. Conclusion: Poor behavior of taking medicine is related to a short dialysis period, poor acceptance and poor satisfaction of dialysis therapy in elderly patients.

Elution of labile fluorescent dye from nanoparticles during biological use.

Cells act as extremely efficient filters for elution of unbound fluorescent tags or impurities associated with nanoparticles, including those that cannot be removed by extensive cleaning. This has consequences for quantification of nanoparticle uptake and sub-cellular localization in vitro and in vivo as a result of the presence of significant amount of labile dye even following extensive cleaning by dialysis. Polyacrylamide gel electrophoresis (PAGE) can be used to monitor the elution of unbound fluorescent probes from nanoparticles, either commercially available or synthesized in-house, and to ensure their complete purification for biological studies, including cellular uptake and sub-cellular localisation. Very different fluorescence distribution within cells is observed after short dialysis times versus following extensive dialysis against a solvent in which the free dye is more soluble, due to the contribution from free dye. In the absence of an understanding of the presence of residual free dye in (most) labeled nanoparticle solutions, the total fluorescence intensity in cells following exposure to nanoparticle solutions could be mis-ascribed to the presence of nanoparticles through the cell, rather than correctly assigned to either a combination of free-dye and nanoparticle-bound dye, or even entirely to free dye depending on the exposure conditions (i.e. aggregation of the particles etc). Where all of the dye is nanoparticle-bound, the particles are highly localized in sub-cellular organelles, likely lysosomes, whereas in a system containing significant amounts of free dye, the fluorescence is distributed through the cell due to the free diffusion of the molecule dye across all cellular barriers and into the cytoplasm.

Hemodialysis Treatment Time

Historical, clinical, economic, and technological developments have driven a shift in clinical practice from predominantly 6-hour-long hemodialysis treatments to much shorter treatment times that are prevalent today. Patients, physicians, and providers had considered shortening dialysis treatments as a means to decrease the overall burden imposed by this necessary life-saving therapy. However, shorter dialysis is not a panacea and may engender trade-offs in terms of patient morbidity and mortality. We examine the literature with the benefit of hindsight and in light of recent studies that have improved understanding of the complex relationship between dialysis dose and outcome. We touch upon the role of dialysis frequency relative to treatment time. We conclude with the suggestion that a new treatment paradigm should consider a minimum adequate dialysis treatment time of 4 hours for the majority of patients, with anything shorter becoming the exception rather than the rule.

“Daily” Dialysis — Lessons from a Randomized, Controlled Trial

The frequency of dialysis was established at three times a week in 1965,1 and this frequency has been used in most centers around the world. Soon after the establishment of this dialysis schedule, an analogue simulation concluded that daily (also known as quotidian) short dialysis sessions would be more effective than thrice-weekly longer dialysis sessions in lowering the average concentration of various markers, such as urea, which rapidly equilibrate among body-fluid compartments.2 With thrice-weekly hemodialysis, the relatively long interval between dialysis sessions results in a “peak-and-valley” effect characterized by fluctuations in the levels of toxins and body-fluid volume, affecting the . . .

Some thoughts on the future of home hemodialysis

Some thoughts on the future of home hemodialysis

Serum alkaline phosphatase and mortality in hemodialysis patients

Alkaline phosphatase is typically considered as an innocent by-stander, but emerging data suggest that alkaline phosphatase might play a pathogenic role in vascular calcification and thus contribute to increased mortality in hemodialysis patients. Longitudinal analyses of the existing HEMO Study database. 1,827 HEMO Study participants. Serum alkaline phosphatase level. OUTCOME AND MEASUREMENTS: All-cause and cardiovascular mortality. Based on the median serum alkaline phosphatase of 97 IU/l, participants were divided into low (< 97 IU/l) and high (> or = 97 IU/l) serum alkaline phosphatase groups. The lower serum alkaline phosphatase group was associated with older age, male gender, non-black race and shorter dialysis years as well as higher serum calcium, higher serum calcium-phosphorus product and lower parathyroid hormone levels. Mean serum liver enzyme values were in the normal range in both groups, but the high alkaline phosphatase group had slightly higher values. In a multivariate time-dependent Cox model using baseline and follow-up values of serum alkaline phosphatase levels, adjusted for demographics, HEMO Study groups, comorbidity, bone metabolism parameters and liver enzymes, each doubling of serum alkaline phosphatase was significantly associated with increased hazard of all-cause (hazard ratio 1.44, 95% CI 1.30 - 1.59) and cardiovascular mortality (hazard ratio 1.35, 95% CI 1.16 - 1.57). Nonstandardized measurements of alkaline phosphatase. Serum alkaline phosphatase is associated with increased mortality in hemodialysis patients, independent of bone metabolism parameters and liver enzymes. Alkaline phosphatase might be a potential therapeutic target in hemodialysis patients.

Calciphylaxis in the current era: emerging 'ironic' features?

Calcific uraemic arteriolopathy (CUA), previously known as calciphylaxis, is a condition of microvascular calcification and thrombosis with resultant tissue necrosis. Due to the rarity of this disease, our understanding of its pathogenesis remains speculative. Iron has emerged as a potential pathogenic contributor to the development of CUA, but investigation into this link is lacking. The purpose of our study was to explore the clinical characteristics of patients diagnosed with CUA at our institution to allow for comparison to available literature. In addition, we wanted to pursue the possibility of iron being a pathogenic contributor to CUA development. We hypothesized that iron would have to be present in areas of microvascular calcification in order to play a contributing pathogenic role and, therefore, wished to establish whether iron deposition was present within available diagnostic CUA skin biopsy specimens. This study included all patients diagnosed with CUA at our institution between 1997 and 2009 whose tissue was available for further analysis. All available diagnostic skin biopsy specimens were reviewed and further analysed by a dermatopathologist. As the goal was to explore the potential pathogenic role of iron, staining for iron deposition within biopsy specimens was undertaken. All available medical and biochemical information about patients was also collated for analytic purposes and related to the biopsy specimen findings. Tissue blocks from 12 patients diagnosed with CUA at our institution were available for further analysis. In this CUA cohort, the average age at diagnosis was 61 years (range, 36-83 years), with six (50%) patients being female. Of these patients, 8 (67%) had diabetes, 8 (67%) had coronary artery disease and 10 (83%) had dyslipidaemia. At the time of diagnosis, eight (67%) were on peritoneal dialysis, two (17%) on haemodialysis and two (17%) were pre-dialysis. Our patients had short dialysis vintage times prior to diagnosis (average, 2.1 years). Iron deposition was detected in areas of microvascular calcification in all diagnostic specimens and was absent in unaffected microvasculature within the same biopsy specimens. The findings of iron deposition in affected microvasculature lend support to the potential role of iron in the complex pathophysiologic cascade of CUA. The implications for iron therapy in high-risk patients and the possible rationale for the use of sodium thiosulphate, a metal chelator, in the treatment of CUA are explored.

Acute Kidney Injury in the Intensive Care Unit

Acute kidney injury (AKI) is a common clinical syndrome with a broad aetiological profile. It complicates about 5% of hospital admissions and 30% of admissions to intensive care units (ICU). During last 20 years has been a significant change in the spectrum of severe AKI such that it is no longer mostly a single organ phenomenon but rather a complex multisystem clinical problem. Despite great advances in renal replacement technique (RRT), mortality from AKI, when part of MOF, remains over 50%. The changing nature of AKI requires a new approach using the new advanced technology. Clinicians can provide therapies tailored to time constraints (intermittent, continuous, or extended intermittent), haemodynamic, and metabolic requirements and aimed at molecules of variable molecular weight. Peritoneal dialysis (PD) is technically the simplest form of RRT and is still commonly used worldwide. The problems include difficulty in maintaining dialysate flow, peritoneal infection, leakage, protein losses, and restricted ability to clear fluid and uraemic wastes. PD is the preferred treatment modality for AKI in pediatric practice. Patients that are hemodynamically stable can be managed with intermittent hemodialysis (IHD), whereby relatively short (3 to 4 h) dialysis sessions may be performed every day or every other day. Patients who are haemodynamically unstable are best managed using continuous renal replacement therapies (CRRT), which allow for continuous fine-tuning of intravascular volume, easier correction of hypervolemia, better solute removal, more accurately correction of metabolic acidosis, and offers possibilities for unlimited energy support. Recently, "hybrid" or sustained low-efficiency dialysis (SLED) was introduced as a method which combines the advantages of IHD with those of CRRT. In this technique, classic dialysis hardware is used at low blood and dialysate flow rates, for prolonged period of time (6 to 12 h/day). SLED offers more haemodynamic stability, better correstion of hypervolaemia, and more adequate solue removal, compared with IHD. In conclusion, AKI in the ICU is increasingly a component of sepsis and MSOF, and the development of rational strategies for initiation, dosing, and effective delivery of RRT in this setting is among the greatest challenges facing nephrologists and intensivists today.

More Intensive Hemodialysis

Clinical outcomes have not improved substantially for patients treated with conventional thrice weekly hemodialysis. More intensive hemodialysis regimens, including daily short dialysis, and nocturnal prolonged dialysis show promise to improve morbidity and mortality. Published studies and trials underway examining these therapies are reviewed.

La modalité d’hémodialyse peut-elle influencer l’état nutritionnel des patients dialysés ?

Malnutrition is frequent in hemodialysis (HD) patients. The HEMO study has shown a progressive decline of nutritional markers, such as body weight, albuminemia and protein intake, in prevalent hemodialysis patients during a 3-year follow-up. In incident dialysis patients, nutritional status usually improves during the first year of HD treatment. Opposite to the HEMO findings, we have shown that nutritional stability was achieved during a 5 year follow-up with sequential long hour dialysis (3 x 6-8 hours/week). Energy and protein intakes are related to the dialysis dose. Moreover, several studies show the nutritional consequences of changing the dialysis prescriptions. The switch from conventional HD to short daily dialysis improves significantly protein and energy intake and albuminemia. Also, increasing treatment time increases significantly the body weight after several months. One of the hypothesis for this effect is that uremia-related middle molecules compromise the patient appetite. Increasing dialysis time or frequency may decrease the level or the time of exposition to these molecules. However, the beneficial effect of hemodiafiltration on HD patients' nutritional status is not spectacular. Another hypothesis is the role of extra-cellular fluid excess and its relationship with inflammation that is deleterious for nutrition. In conclusion, dialysis adequacy is a mandatory prerequisite when facing a malnourished HD patient. Increasing time or frequency must be part of the therapeutic thought in such situation.