Efficacy of Medium Cut-Off Dialyzer and Comparison with Standard High-Flux Hemodialysis

Effect of medium cut-off membranes on Pentosidine and N-(carboxymethyl) lysine levels in uncontrolled diabetic hemodialysis patients

INTRODUCTION

Patients on hemodialysis, especially with diabetes, face elevated cardiovascular events. A major contributor to complications associated with diabetes is advanced glycation end products (AGEs). Removing these compounds is challenging in traditional hemodialysis. Medium-cut-off (MCO) membranes potentially remove toxins without significant albumin loss. This study explored how MCO membranes impact AGEs levels in uncontrolled diabetic patients undergoing hemodialysis.

METHODS

Sixteen patients received MCO membrane dialysis, while others used high-flux (HF) membranes. After 12 sessions, the dialyzers were switched, totaling 24 sessions. Blood samples at trial initiation (T0), session 12 (T1) and session 24 (T2) tested for CML, Pentosidine, laboratory parameters.

RESULTS

Switching dialyzers showed increased albumin with MCO-to-HF and decreased with HF-to-MCO, albeit nonsignificant (p = 0.5/p = 0.1). Patients on MCO had lower albumin levels than HF (p = 0.03/p = 0.6, respectively). Hemodialysis with MCO demonstrated lower levels of CML/Pentosidine compared to HF (p = 0.09/p = 0.9 for CML; p = 0.04/p = 0.3 for Pentosidine). Transitioning to HF led to elevated levels (p = 0.4/p = 0.09 for CML; p = 0.3/p = 0.07 for Pentosidine).

CONCLUSION

MCO dialysis in diabetic individuals notably reduces AGE levels.

The short-term effect of hemodialysis on the level of high-sensitive cardiac troponin T - A systematic review

INTRODUCTION

Patients with end-stage renal disease (ESRD) have an increased risk of cardiovascular disease, but interpreting cardiac troponin is difficult in this population. The effect of renal replacement therapy (RRT) is important to consider when interpreting serial cardiac troponin T (cTnT) results for patients with ESRD suspected of acute coronary syndrome (ACS). The aim of this systematic review is to answer how low-flux hemodialysis (LF-HD), high-flux hemodialysis (HF-HD), and hemodiafiltration (HDF) affect the blood concentration of high-sensitive cardiac troponin T (hs-cTnT).

METHOD

Several databases were searched and identified records were evaluated independently by two of the authors. Pre- and postdialysis hs-cTnT concentrations together with other relevant data were extracted from the included studies. The quality (potential bias and applicability issues) were assessed for each of the included studies.

RESULTS

The literature search identified 2,540 records and 15 studies were included. The relative pre- to postdialysis change of hs-cTnT varied from -41 to 29%. LF-HD increased the hs-cTnT concentration with relative changes between 2 and 17%. HDF decreased the concentration with relative changes from -41% to -9%. Both increases and decreases were seen for HF-HD (-16% to 12%).

DISCUSSION/CONCLUSION

In this systematic review, we found LF-HD to increase the hs-cTnT concentration and HDF to decrease the concentration. Results for HF-HD and unspecified HD are more heterogeneous. Because of the differences between the included studies, a meta-analysis was not meaningful. This systematic review can help with the assessment of patients with ESRD suspected of ACS in relation to hemodialysis/HDF treatment.

Medium cut-off dialyzer for middle molecular uremic toxins in AKI and chronic dialysis

Uremic toxins accumulate in patients affected by renal failure and can deposit in different organs, including the kidneys and heart. Given their physicochemical characteristics, uremic toxins can contribute to organ dysfunction due to several pathobiological actions at cellular and molecular levels. Several uremic compounds have been described in serum and plasma from patients with acute kidney injury (AKI) and kidney failure; they are usually classified based on their molecular size and protein-binding properties. In this scenario, new dialytic approaches have been proposed in the last few years with the aim of improving uremic toxin removal. Recent studies which focused on the use of medium cut-off membranes in patients on chronic hemodialysis have shown a discrete ability to remove β2-microglobulin and other middle molecules, such as kappa and lambda free light chains, complement factor D and α1-microglobulin. However, current evidence is mainly based on the impact on short-term outcomes and, consequently, longer observational studies are necessary to confirm the efficacy and safety of the medium cut-off dialyzer. Here we present the state-of-the-art on the clinical application of medium cut-off membranes in AKI and chronic dialysis patients.

Comparison of the medium cutoff dialyzer and postdilution hemodiafiltration on the removal of small and middle molecule uremic toxins

BACKGROUND

The medium cutoff (MCO) dialyzer increases the removal of several middle molecules more effectively than high-flux hemodialysis (HD). However, comparative data addressing the efficacy and safety of MCO dialyzers vs. postdilution hemodiafiltration (HDF) in Korean patients are lacking.

METHODS

Nine patients with chronic HD were included in this pre-post study. Patients underwent HD with an MCO dialyzer for 4 weeks, followed by a 2-week washout period using a high-flux dialyzer to minimize carryover effects, and then turned over to postdilution HDF for 4 weeks. Reduction ratios and differences in the uremic toxins before and after dialysis were calculated from the MCO dialysis, postdilution HDF, and high-flux HD. In the in vitro study, EA.hy926 cells were incubated with dialyzed serum.

RESULTS

Compared to postdilution HDF, the MCO dialyzer achieved significantly higher reduction ratios for larger middle molecules (myoglobin, kappa free light chain [κFLC], and lambda FLC [λFLC]). Similarly, the differences in myoglobin, κFLC, and λFLC concentrations before and after the last dialysis session were significantly greater in MCO dialysis than in postdilution HDF. The expression of Bax and nuclear factor κB was decreased in the serum after dialysis with the MCO dialyzer than with HDF.

CONCLUSION

Compared with high-volume postdilution HDF, MCO dialysis did not provide greater removal of molecules below 12,000 Da, whereas it was superior in the removal of larger uremic middle molecule toxins in patients with kidney failure. Moreover, these results may be expected to have an anti-apoptotic effect on the human endothelium.

Efficacy and Safety of the Medium Cut-Off Elisio HX Dialyzer

INTRODUCTION

The medium cut-off Elisio HX dialyzer by Nipro became commercially available in Europe in 2021, but there are still no reports of in vivo data. This study aimed to evaluate the safety and efficacy of it compared with previously evaluated hemodialysis (HD), expanded HD (HDx), and postdilution hemodiafiltration (HDF) treatments.

METHODS

A prospective study was carried out on 18 patients who underwent 5 dialysis sessions: FX80 Cordiax in HD, Elisio H19 in HD, Elisio HX19 in HDx, Theranova 400 in HDx, and FX80 Cordiax in HDF. The reduction ratios of urea, creatinine, ß2-microglobulin, myoglobin, kappa FLC, prolactin, α1-microglobulin, α1-acid glycoprotein, lambda FLC, and albumin were compared. Dialysate albumin loss was measured.

RESULTS

The comparison between the different dialysis modalities revealed no difference for small molecules, but HDx and HDF were significantly more efficient than HD for medium and large molecule removal. The efficacy of Elisio HX19 dialyzer in HDx was similar to the Theranova 400, superior to both dialyzers in HD, and slightly lower than HDF. Albumin losses in dialysate with HD dialyzers were less than 1 g, but between 1.5 and 2.5 g in HDx and HDF. The global removal score (GRS) values with HDx treatments were statistically significantly higher than those with HD. The highest GRS was obtained with the helixone dialyzer in HDF.

CONCLUSIONS

The new MCO dialyzer, Elisio HX, performs with excellent behavior and tolerance. It represents an upgrade compared to their predecessor and is very close to the removal capacity of HDF treatment.

Comparison of four medium cut-off dialyzers

BACKGROUND

Recently, several pharmaceutical companies have developed new medium cut-off (MCO) dialyzers for expanded hemodialysis (HDx). This study aimed to compare the safety and efficacy of four MCO dialyzers, against each other and versus high-flux hemodialysis (HD) and post-dilution hemodiafiltration (HDF).

METHODS

A prospective study was carried out on 23 patients who underwent six dialysis sessions: two sessions with the FX80 Cordiax in HD and HDF, and four HDx sessions with the Phylther 17-SD, Vie-18X, Elisio HX19 and Theranova 400 dialyzers. The reduction ratios (RRs) of urea, creatinine, β2-microglobulin, myoglobin, kappa free immunoglobulin light chain (κFLC), prolactin, α1-microglobulin, α1-acid glycoprotein, lambda (λFLC) and albumin were compared. Dialysate albumin loss was also measured.

RESULTS

The differences in efficacy between the evaluated dialyzers were minimal in small molecules and even up to the size of β2-microglobulin. The main differences were found between myoglobin, κFLC, prolactin, α1-microglobulin and λFLC RRs, in which all four MCO dialyzers, with similar efficacy, were clearly superior to HD and slightly inferior to HDF treatment. Albumin losses in the dialysate with HD dialyzers were <1 g and between 1.5 and 2.5 g in HDx and HDF. The global removal score values were similar in all four HDx treatments, and again significantly higher than those with HD.

CONCLUSIONS

The results of the four MCO dialyzers evaluated in this study showed good efficiency, with no significant performance differences between them while being completely safe in terms of albumin loss. Likewise, the study confirms the superiority of HDx over high-flux HD with an efficacy close to that of post-dilution HDF.

Dialysis and Extracorporeal Therapies for Enhanced Elimination of Toxic Ingestions and Poisoning

Poisoning and toxic ingestions cause significant morbidity and mortality worldwide. Extracorporeal therapies such as dialysis, haemoperfusion and plasma exchange are selectively applied to patients with severe intoxications unresponsive to standard interventions and can be lifesaving. Extracorporeal therapies are a complex but fundamental aspect of the practice of nephrology. Without high-quality evidence to guide implementation, an understanding of toxicokinetics and the physiochemical principles of the enhanced elimination techniques is especially important. This review provides a comphrensive, user-friendly outline of the application of extracorporeal therapy in the poisoned patient.

Hemodiafiltration (HDF) versus expanded hemodialysis (HDx)

Medium cutoff (MCO) membranes have resulted in a novel dialyzer class designed to improve membrane permeability and have been postulated as an alternative to online hemodiafiltration since MCO membranes may achieve similar solute clearances. These membranes have been incorporated into clinical practice, and the term expanded HD (HDx) has been proposed to differentiate from high-flux hemodialysis. Efficacy, safety, and quality of life comparison of HDF versus HDx have been reviewed in this article.

Effects of Expanded Hemodialysis with Medium Cut-Off Membranes on Maintenance Hemodialysis Patients: A Review

Kidney failure is associated with high morbidity and mortality. Hemodialysis, the most prevalent modality of renal replacement therapy, uses the principle of semipermeable membranes to remove solutes and water in the plasma of patients with kidney failure. With the evolution of hemodialysis technology over the last half century, the clearance of small water-soluble molecules in such patients is adequate. However, middle molecules uremic toxins are still retained in the plasma and cause cardiovascular events, anemia, and malnutrition, which significantly contribute to poor quality of life and high mortality in maintenance hemodialysis patients. A new class of membrane, defined as a medium cut-off (MCO) membrane, has emerged in recent years. Expanded hemodialysis with MCO membranes is now recognized as the artificial kidney model closest to natural kidney physiology. This review summarizes the unique morphological characteristics and internal filtration–backfiltration mechanism of MCO membranes, and describes their effects on removing uremic toxins, alleviating inflammation and cardiovascular risk, and improving quality of life in maintenance hemodialysis patients.

Expanded Haemodialysis as a Current Strategy to Remove Uremic Toxins

Chronic kidney disease (CKD) is characterized by the retention of solutes named uremic toxins, which strongly associate with high morbidity and mortality. Mounting evidence suggests that targeting uremic toxins and/or their pathways may decrease the risk of cardiovascular disease in CKD patients. Dialysis therapies have been developed to improve removal of uremic toxins. Advances in our understanding of uremic retention solutes as well as improvements in dialysis membranes and techniques (HDx, Expanded Hemodialysis) will offer the opportunity to ameliorate clinical symptoms and outcomes, facilitate personalized and targeted dialysis treatment, and improve quality of life, morbidity and mortality.