Membrane flux not biocompatibility determines beta-2-microglobulin levels in hemodialysis patients.
BACKGROUND
Serum beta(2)-microglobulin (beta(2)M) levels are important in dialysis-related amyloid deposition but can be influenced by dialysis technique.


METHODS
We measured beta(2)M levels in 3 centres using different dialysis regimes. Centre 1 (73 patients) used high-flux biocompatible, centre 2 (72 patients) low-flux biocompatible and centre 3 (142 patients) cuprophane dialysers.


RESULTS
beta(2)M levels were lower with high-flux biocompatible than with low-flux biocompatible or cuprophane dialysis (22.3 +/- 5.4 vs. 43.4 +/-13.7 and 37.6 +/-13.1 mg/l, respectively; p < 0.001). Levels were higher with low-flux biocompatible than with cuprophane dialysis (p < 0.001), but not if patients dialysed over 10 years were excluded. With low-flux biocompatible (47.4 +/- 9.8 vs. 38.7 +/- 15.2 mg/l; p < 0.01) and cuprophane dialysis (43.4 +/- 8.2 vs. 36.7 +/- 13.0 mg/l; p < 0.02), beta(2)M levels were higher in patients dialysed over 5 years than in those dialysed less. Despite beta(2)M levels increasing as residual renal function declined, there was no similar rise with high-flux biocompatible dialysis.


CONCLUSIONS
Techniques allowing significant convection maintain lower beta(2)M levels over many years. Membrane flux, not biocompatibility, is the main determinant of beta(2)M levels in routine practice.
Pickett
Thomas M
TM
Directorate of Medicine, Gloucestershire Royal Hospital, Gloucester, UK.
Cruickshank
Alastair
A
Greenwood
Roger N
RN
Taube
David
D
Davenport
Andrew
A
Farrington
Ken
K
D000368:Aged; D000686:Amyloidosis / Q000209:etiology; D001672:Biocompatible Materials; D002482:Cellulose / Q000031:analogs & derivatives*; D003430:Cross-Sectional Studies; D017583:Hemodiafiltration; D006801:Humans; D008567:Membranes, Artificial; D008875:Middle Aged; D006435:Renal Dialysis / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D051437:Renal Insufficiency / Q000628:therapy; D001613:beta 2-Microglobulin / Q000097:blood*
D001672:Biocompatible Materials; D008567:Membranes, Artificial; D001613:beta 2-Microglobulin; D002482:Cellulose; C009865:cuprammonium cellulose