Kidney Week Educational Symposia-Removal of Large Middle Molecular Uremic Toxins: Room for Innovation

Video Transcription

Video Summary

At Kidney Week 2020, moderator Zaheer Kaleem frames dialysis innovation around persistently high mortality (up to 25% in the first year in some regions) and patient priorities beyond Kt/V, urging attention to middle and large uremic solutes that conventional hemodialysis clears poorly.<br /><br />Peter Stenvinkel reviews how end-stage kidney disease promotes “uremic aging” driven by chronic inflammation, oxidative stress, and toxin accumulation. Large middle molecules (often >25 kDa) are linked to cardiovascular disease, immune dysfunction, and protein-energy wasting. Key examples include IL-6 (a robust predictor of mortality), FGF23 (predicts death and cardiac structural disease), TNF-related pathways, YKL-40, and free light chains. He highlights newer approaches—especially expanded hemodialysis (HDx) using medium cut-off (MCO) membranes—to enhance removal of these toxins, with moderate albumin losses (2–4 g/treatment) that may be acceptable or possibly beneficial.<br /><br />Colin Hutchison explains the technology: adding convection (e.g., high-volume hemodiafiltration) improves large-solute clearance, but membrane pore-size non-uniformity historically limited expansion due to albumin loss risk. MCO membranes tighten pore distribution to clear large middle molecules beyond β2-microglobulin while minimizing albumin loss and avoiding endotoxin backfiltration. Trials (e.g., REMOVAL-HD and a CJASN RCT) show stable serum albumin and improved clearance/reduction of kappa and lambda free light chains. Early signals suggest symptom/functional benefits, but definitive outcome trials are still needed.

Asset Subtitle

Sahir Kalim, Peter Stenvinkel, Colin Hutchison
Support is provided by an educational grant from Baxter Healthcare Corporation.

Keywords

Kidney Week 2020

dialysis innovation

expanded hemodialysis (HDx)

medium cut-off (MCO) membranes

large middle molecules

uremic toxins

uremic aging

free light chains (kappa/lambda)

albumin loss