Removal of large middle molecules via haemodialysis with medium cut-off membranes at lower blood flow rates: an observational prospective study

Abstract

Background: Online haemodiafiltration (OL-HDF) may improve middle molecular clearance in contrast to conventional haemodialysis (HD). However, OL-HDF requires higher convective flows and cannot sufficiently remove large middle molecules. This study evaluated the efficacy of a medium cutoff (MCO) dialyser in removing large middle molecular uraemic toxins and compared it with that of conventional high-flux (HF) dialysers in HD and predilution OL-HDF. Methods: Six clinically stable HD patients without residual renal function were investigated. Dialyser and treatment efficacies were examined during a single midweek treatment in three consecutive periods: 1) conventional HD using an HF dialyser, 2) OL-HDF using the same HF dialyser, and 3) conventional HD using an MCO dialyser. Treatment efficacy was assessed by calculating the reduction ratio (RR) for β2-microglobulin (β2M), myoglobin, κ and λ free light chains (FLCs), and fibroblast growth factor (FGF)-23 and measuring clearance for FLCs. Results: All three treatments showed comparable RRs for urea, phosphate, creatinine, and uric acid. MCO HD showed greater RRs for myoglobin and λFLC than did HF HD and predilution OL-HDF (myoglobin: 63.1 ± 5.3% vs. 43.5 ± 8.9% and 49.8 ± 7.3%; λFLC: 43.2 ± 5.6% vs. 26.8 ± 4.4% and 33.0 ± 9.2%, respectively; P < 0.001). Conversely, predilution OL-HDF showed the greatest RR for β2M, whereas MCO HD and HF HD showed comparable RRs for β2M (predilution OL-HDF vs.

Slipping Through the Pores: Hypoalbuminemia and Albumin Loss During Hemodialysis

“…These findings have been replicated in a small (N = 6) study from South Korea demonstrating greater albumin losses with an MCO membrane (Theranova 400; median 3.16 g per session) than with a high flux membrane (Rexeed™-21A; Asahi Kasei Medical Co., Ltd., Tokyo, Japan; median 0.06 g per session). 61 The loss of albumin with MCO dialyzers does not appear to be impacted by increasing the membrane surface from 1.7 m 2 (Theranova 400) to 2.0 m 2 (Theranova 500 TM ; Baxter Healthcare Corporation, Deerfield, IL, USA). 62 In summary, the median albumin loss per HD session with MCO dialyzers appears to be approximately 3 g, with some variability across individuals.…”

May Medium Cut-Off Dialysis Membranes Have Impact on Outcome of COVID-19 Hemodialysis Patients?

“…MCO is a novel type membrane for HD. In a study performed by Kim et al, it was showed that HD with MCO membranes achieved signi cantly greater reduction ratio of large middle molecules (including cytokines such as IL-1 and IL-6), than HD with conventional membranes and online-hemodio ltration [19].…”

“…Three type of hemodialysis membranes are described: low ux (LF), high ux (HF) and medium cut-off (MCO) [18]. MCO membranes may make greater clearances and intradialytic reduction ratios for large-middle molecules (including cytokines) than LF and HF membranes [19].…”

High-volume online haemodiafiltration treatment and outcome of end-stage renal disease patients: more than one mode

“…No significant differences in the RRs of small and middle molecules, and the global removal scores were observed between MCO and HDF dialyzers. MCO dialyzer membranes even may allow the removal of larger uraemic toxins not previously targeted by current maintenance HD techniques [26,27]. The MCO dialyzer membranes offer effective retention of bacterial products from conventional dialysis fluid without requiring an ultrapure water supply or other HDF infrastructure [28].…”