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Abstract: TH-PO351

Higher In Vivo β2 Microglobulin Clearance in Expanded Hemodialysis: Preliminary Results of a Cross-Over Trial

Session Information

Category: Dialysis

  • 701 Dialysis: Hemodialysis and Frequent Dialysis


  • Cordeiro, Isis SF, University of São Paulo, São Paulo, SP, Brazil
  • Pereira, Benedito J., University of São Paulo, São Paulo, SP, Brazil
  • Silveira, Marcelo Duarte, University of São Paulo, São Paulo, SP, Brazil
  • Cordeiro, Lilian, University of São Paulo, São Paulo, SP, Brazil
  • Abensur, Hugo, University of São Paulo, São Paulo, SP, Brazil
  • Elias, Rosilene M., University of São Paulo, São Paulo, SP, Brazil
  • Silva, Bruno C., University of São Paulo, São Paulo, SP, Brazil

In conventional hemodialysis (HD), β2 microglobulin (β2M), a medium-range molecule (MRM), tend to accumulate in tissues. Online hemodiafiltration (olHDF) increases MRM clearance at expense of more complex dialysis machines. The development of medium cut-off with high albumin retention onset membranes allowed a new therapy, known as expanded hemodialysis (HDx). However, so far, in vivo extraction of MRM in this modality is unknown.


Prospective trial, in which 8 patients switched from HD to olHDF or HDx for 1 month, and then crossed to the other modality for another month, after a washout period of 2 weeks. Pre- and post-dialysis urea, albumin, phosphorus, and β2M were measured in blood and in a sample of homogeneously collected spent dialysate, throughout dialysis procedure. High-flux Diacap™ dialyzers (BBraun, Germany) were used both in HD and in olHDF, while Theranova 400™ dialyzers (Gambro, Germany) in HDx. Ongoing trial is registered at NCT03274518.


Mean age was 48 ± 13 years (75% men), and dialysis duration was 225 ± 12 minutes. Total convection volume in olHDF was 20.3 ± 1.1L. β2M clearance was higher in HDx in comparison to high-flux HD and olHDF (62.2 ± 10.2 vs. 36.5 ± 2.6, p = 0.012 and 45.5 ± 18.3 ml/min, p = 0.026 respectively). β2M extraction during dialysis was higher in HDx in comparison to olHDF (196.4 ± 31.3 vs. 122.1 ± 43.8 mg, p=0.023). Pre-dialysis serum β2M was not different among the three modalities.


Preliminary results of this trial indicate that in vivo clearance and total mass extraction of β2M is higher in HDx in comparison to olHDF.

Laboratorial data from patients, according to dialysis modality
Ultrafiltration (ml)2625 ± 12332775 ± 9772900 ± 1039ns
Spent dialysate (L)182.6 ± 8.8182.8 ± 9.3182.9 ± 9.1ns
Phosphorus (mg/dl)3.6 ± 1.14.8 ± 0.94.3 ± 1.9ns
Phosphorus extraction (mg)635 ± 344683 ± 168775 ± 307ns
Albumin (g/dl)3.8 ± 0.34.0 ± 0.33.7 ± 0.3ns
Albumin extraction (g)23.1 ± 1.323.1 ± 10.518.3 ± 0.9ns
β2M (ug/ml)23.7 ± 0.523.2 ± 6.927.8 ± 5.5ns
β2M extraction (mg)136.7 ± 22.9122.1 ± 43.8†196.4 ± 31.3†0.023†
β2M clearance (ml/min)36.5 ± 2.6*45.5 ± 18.3†62.2 ± 10.2*†0.012*; 0.026†
Urea (mg/dl)164 ± 29162 ± 23161 ± 36ns
Urea extraction (g)43 ± 1642 ± 1445 ± 18ns

* HD vs HDx; † olHDF vs HDx