Abstract
An evaluation of dialyzers was performed to realize the fundamental difference between the two groupes of dialyzers available in Japan, 5 types of dialyzer assembled with so-called high-performance membrane (HPM-dialyzers) and 8 types of conventional dialysis membrane (CDM-dialyzer). In each dialyzer, NaCl-clearance and ultrafiltration ratio (UFR) were examined in vitro as well as sieving co-efficient (%SC) for bioactive substances including hormones, albumin, immunoglobulins and β2 microglobulin (BMG) ex vivo. HPM-dialyzers revealed 14% lower clearance and 6 times higher UFR than those of CDM-dialysers. In HPM-dialyzer, the %SC for BMG was high enough ranging from 38.2% to 64.0% except one type assembled with PMMA, however, their high permeability allowed many hormones with molecular weight from 272 to 36, 000 to leak out by innegligible quantities. Loss of albumin was much more in HPM-dialyzers. In conclusion, so-called HPM-dialyzers can be characterized by their low clearance, high UFR and high permeability for low molecular weight proteins as BMG and moreover many hormones. On clinical application of HPM-dialyzers, the drawback of albumin leakage and loss of bioactive substances such as many hormones should be fully evaluated as well as the prospective benefit on removing BMG.
