Biomarkers for evaluation of clinical outcomes of hemodiafiltration.

β2-Microglobulin (β2-MG) is the substance that causes dialysis amyloidosis, and its predialysis value is useful for evaluating the quality of dialysis therapy itself. In addition, β2-MG is also an important biomarker for evaluating the removal performance of hemodialysis and hemodiafiltration (HDF). However, since β2-MG has a molecular weight of 11.8 kDa and can be efficiently removed by diffusion with existing high-performance dialyzers, a higher molecular weight substance should be used for evaluating removal performance of HDF, in which diffusion and convection are performed simultaneously. α1-Microglobulin (α1-MG) has a molecular weight of 33 kDa, and it is removed by convection during dialysis. When we used α1-MG to evaluate the removal performance of HDF in a study based on our own cases, we were able to describe the distinctive features and benefits of HDF with precision. α1-MG removal rate exactly paralleled the changes in symptoms. Kt/V and the β2-MG removal rate, however, did not undergo significant changes as the symptoms fluctuated. α1-MG should be used as a biomarker for evaluation of clinical outcomes of HDF.