Polymethylmethacrylate dialyzer

Since SARS-CoV-2 spread through China at the end of 2019, COVID-19 has been probably the most difficult challenge in the last decades for healthcare systems all around the world, still representing a danger for fragile patients with different comorbidities. Chronic dialysis patients affected by COVID-19 experienced severe disease with a higher mortality rate compared to the general population. Morbidity and mortality of this severe acute respiratory syndrome depend on both acute respiratory failure and systemic immunological involvement with consequent inflammation-mediated injury...

INTRODUCTION: High-flux hemodialysis membranes may modulate the cytokine storm of SARS-CoV-2, but their impact on chronic hemodialysis (CHD) patients is unknown. The aim of the study was the evaluation of asymmetric cellulose triacetate (ATA) and polymethylmethacrylate (PMMA) dialyzers on inflammatory markers and clinical outcomes in CHD patients with SARS-CoV-2. METHODS: A prospective, observational study on CHD patients with SARS-CoV-2 was carried out. Patients were enrolled from March 2020 to May 2021...

Polymethylmethacrylate (PMMA) hollow fiber membranes are one of the synthetic polymer hollow fiber membranes used to the hollow fiber artificial kidney. A PMMA hollow fiber membrane (PMMA membrane) has unique properties including the uniform structure and the adsorption property. Hemodialyzers using PMMA membranes, Filtryzer®, were approved in Japan in 1977 and have been used worldwide for over 40 years and so is a historical hemodialyzer.Various types in Filtryzer® having different pore sizes are developed and used in the clinical field...

Toray has created a new generation of dialyzers, the polysulphone (TS) UL series, and polymethylmethacrylate (PMMA) NF-U series, which offer enhanced efficacy over the previous TS-S series and NF-H series. The aim of this study was to evaluate the safety and efficacy of these dialyzer series versus contrasted expanded hemodialysis (HDx) and postdilution hemodiafiltration (HDF). We conducted a prospective study in 12 patients. Each patient underwent six dialysis sessions: FX80 Cordiax in HD, Toraysulfone TS-1...

Adsorption properties of hemodialyzers are traditionally retrieved from diffusive treatments and mainly focused on inflammatory markers and plasma proteins. The possible depurative enhancement of middle and high molecular weight solutes, as well as protein-bound uremic toxins by adsorption in convective treatments, is not yet reported. We used discarded plasma exchanges from uremic patients and out-of-date erythrocytes as a novel in vitro uremic precursor matrix to assess removal and adsorption patterns of distinct material and structure but similar surface hemodialyzers in hemodialysis and on-line hemodiafiltration treatments...

BACKGROUND: Little information is available regarding which type of dialyzer membrane results in good prognosis in patients on chronic hemodialysis. Therefore, we conducted a cohort study from a nationwide registry of hemodialysis patients in Japan to establish the association between different dialyzer membranes and mortality rates. METHODS: We followed 142,412 patients on maintenance hemodialysis (female, 39.1%; mean age, 64.8 ± 12.3 years; median dialysis duration, 7 [4-12] years) for a year from 2008 to 2009...

BACKGROUND: Little information is available regarding the type of dialyzer which results in good prognosis. This study is aimed at investigating the association between 7 types of dialyzers and 2-year mortality. METHODS: We conducted a cohort study using data from a nationwide registry of the Japanese Society for Dialysis Therapy. Subjects were 136,676 patients on maintenance hemodialysis (HD) between 2009 and 2011 who underwent maintenance HD for at least 2 years and were treated with one of the following 7 types of high-performance membrane dialyzers: cellulose triacetate (CTA), ethylene vinyl alcohol (EVAL), polyacrylonitrile (PAN), polyester polymer alloy (PEPA), polyethersulfone (PES), polymethylmethacrylate (PMMA), and polysulfone (PS)...

BACKGROUND: Immunoglobulin light chains are classified as middle molecule uremic toxins able to interact with B lymphocyte membranes leading to the activation of transmembrane signaling. The ensuing impairment of neutrophil function can contribute to the chronic inflammation state of uremic patients, and the increased risk of bacterial infections or vascular calcifications. The aim of this crossover observational study was to assess the difference in free light chain removal by three different hemodialysis filters in patients not affected by multiple myeloma...

No abstract text is available yet for this article.

A 75-year-old Japanese man presented with pruritic blisters and macules on his trunk and extremities. He had been on hemodialysis for 4 years because of chronic renal failure, and in recent months, a polymethylmethacrylate membrane had been used for dialysis. After a change in dialysis membrane to a cellulose triacetate membrane, pruritic tense blisters developed on the extremities in combination with marked blood eosinophilia. Physical examination showed erythematous macules and tense blisters on the trunk and extremities...

INTRODUCTION: Polymethylmethacrylate (PMMA) membranes can adsorb a wide variety of uremic toxins including serum free light chains (sFLC). However, limited data are available regarding the clinical use of PMMA in multiple myeloma patients and its maximum adsorption capacity in this setting. AIM: This study aimed to measure the capacity of PMMA to adsorb sFLC and identify strategies to improve its efficiency in clinical practice. METHODS: Ten patients with dialysis-dependent renal failure and high levels of sFLC were included in the study...

Prurigo nodularis is a skin disease with unknown origin which is frequent in patients on maintenance renal replacement therapy. Here, we report a patient who was dialyzed for more than 10 years with different dialyzers using different dialyzer membranes. Each time when the patient was switched to a polymethylmethacrylate membrane (Filtryzer BK-1.6P), itching and skin lesions disappeared completely. This effect could be verified three times.

AIM: Most chronic uremic patients undergoing dialysis show a diminished antibody response to anti-hepatitis B vaccination (anti-HBv) and at this regard high sCD40 serum levels seem to inhibit the immunocompetent response. A simple and feasible technique for removing soluble sCD40 by adsorption is standard bicarbonate dialysis performed by polymethylmethacrylate (PMMA) dialyzers able to remove serum high molecular weight toxins. Aim of the study was to assess whether PMMA dialyzers could enhance the long-term response to anti-HBv in non-responder (NR) ESRD patients...

The aim of this study was to investigate whether continuous hemodiafiltration (CHDF) with a high-performance membrane dialyzer made of polymethylmethacrylate (PMMA-CHDF) in the treatment of septic shock patients with acute renal failure (ARF) is clinically relevant. 30 patients were treated with PMMA-CHDF. 13 patients treated with CHDF used a hemofilter made of polyacrylonitrile membrane (PAN-CHDF). Systolic blood pressure significantly increased in the PMMA-CHDF group following 24 h of treatment (p < 0...

Sustained high-efficiency daily diafiltration using a mediator-adsorbing membrane (SHEDD-fA) is an effective, intensive modality for sepsis treatment. Here we describe the effectiveness of SHEDD-fA, which makes the best use of three principles: dialysis, filtration and adsorption, for mediator removal in the treatment of severe sepsis. SHEDD-fA was initiated after adequate fluid resuscitation and catecholamine support had been provided. A large (2.1 m(2)) polymethylmethacrylate membrane dialyzer was placed in the blood circuit...

Forty years have passed since the polymethylmethacrylate (PMMA) membrane was first developed. This article reviews its history and explains its longevity. The membrane was developed through application of a stereocomplex phenomenon that is observed upon mixture of isotactic and syndiotactic PMMA polymers. Filtryzer(TM) B1 and B2 were approved in Japan in 1977. B1 was the pioneer high-performance membrane model and B2 was a model that simulated a low-flux cellulosic membrane. The development of B1 led to the development of the dialysis machine with an ultrafiltration rate (UFR)-controlling function because the UFR of B1 was too high to control using transmembrane pressure control...

BACKGROUND: Following the introduction of modified cellulosic and then synthetic membrane dialyzers, it was realized that the dialyzer bio-incompatibility depends on the membrane composition. We designed a prospective, randomized, cohort study of 6 months to determine several parameters of biocompatibility in maintenance hemodialysis (MHD) patients treated with four different membrane dialyzers. METHODS: There were 60 MHD patients enrolled in the study. In baseline, synthetic low-flux dialyzer, polysulfone (PS) membrane was used in all patients for at least 3 months...

Selecting dialyzers is more important for blood purification in critical care because other therapeutic options (especially amount of dialysate) are usually limited. Adsorption is a major mechanism of removing toxic substances from patients in these treatments. Several commercial dialyzers designed for acute blood purification therapy were investigated by performing aqueous ultrafiltration experiments to demonstrate the adsorptive importance of membrane materials. Polymethylmethacrylate showed strong adsorptive characteristics to α-chymotripsinogen A (MW 25,000) but showed much less adsorptive characteristics to cytochrome C (MW 12,400)...

Commercial dialyzers were investigated both in vivo and in vitro for a better selection of dialyzers for hemodiafiltration (HDF) therapy. In in vivo online HDF, since a reduction rate of α(1)-microglobulin (α(1)-MG) was determined by the amount of albumin loss regardless of blood flow rate (Q(B)), ultrafiltration rate (Q(F)), and the performance of dialyzer, there is no preference for choice of dialyzers to remove α(1)-MG except for albumin sieving. It was clinically verified that albumin leakage mainly occurred in the first 60 min of treatment even in HD with a polysulfone dialyzer...

Since therapeutic conditions, especially the amount of dialysate, are usually limited in continuous renal replacement therapy (CRRT), selecting an appropriate membrane is more crucial than that in chronic hemodialysis. Under such circumstances, the use of a membrane with adsorption is expected to remove a larger amount of target substances in CRRT. Five commercial dialyzers were investigated to demonstrate the importance of membrane characteristics. The adsorptive characteristics of polymethylmethacrylate (PMMA) membrane were relatively low for cytochrome c (MW 12,400), very strong for alpha-chymotrypsinogen A (MW 25,000) and relatively strong for albumin (MW 66,000), which may be understood that the adsorption in PMMA has the optimal molecular size...