beta(2)-microglobulin kinetics in nocturnal haemodialysis.
BACKGROUND
beta(2)-Microglobulin (beta(2)m) is a major component of dialysis-related amyloidosis. The available therapeutic options do not permit normalization of the serum beta(2)m level. In a cross-over trial, we studied the kinetics of beta(2)m during two different dialytic techniques.


METHODS
Ten stable, anuric end-stage renal disease patients were studied during two consecutive weeks of three conventional (CHD) and six nocturnal haemodialysis (NHD) sessions. CHD was performed for 4 h three times weekly using a polysulfone dialyser (F80, surface area of 1.8 m(2)) with a mean blood and dialysate flow rate of 401+/-91.6 and 514+/-10.9 ml/min, respectively. The NHD was done with a smaller dialyser (F40, surface area of 0.7 m(2)) and lower blood (281+/-17 ml/min) and dialysate flow rates (99+/-1.2 ml/min) for 8 h, six nights a week.


RESULTS
Weekly removal of urea (51.6+/-24.6 vs 43.1+/-20.5 g) and creatinine (8501+/-5204 vs 6319+/-4134 mg) were comparable with the two modalities of dialysis but the mass of beta(2)m removed was significantly higher with NHD (127+/-48 vs 585+/-309 mg, P<0.001), with a percentage reduction in serum level of 20.5+/-5.8 vs 38.8+/-7. 1% (P<0.0001) and a Kt/V(beta2m) of 0.21+/-0.09 vs 0.56+/-0.17 (P<0. 0006). The mean post-dialysis beta(2)m (20.8+/-6.3 vs 14.0+/-3.8 mg/dl, P=0.02), Tac(beta2m) (26.2+/-5.2 vs 19.8+/-3.8 mg/dl, P=0.02) and pre-dialysis beta(2)m (beta(2)m(pre)) at the end of 1 week of therapy (24.4+/-7.6 vs 19.0+/-3.4 mg/dl, P=0.02) were lower with NHD. Long-term follow-up data were available in 13 and seven patients at the end of 1 and 2 years, respectively. Serum beta(2)m(pre) levels progressively declined from 27.2+/-11.7 mg/dl at initiation of NHD to 13.7+/-4.4 mg/dl by 9 months, and they remained stable thereafter.


CONCLUSIONS
NHD provides a much higher clearance of beta(2)m than CHD, leading to a long-term decrease in the pre-dialysis concentration of beta(2)m.
Raj
D S
DS
Department of Medicine, Louisiana State University Medical Center, Shreveport, Louisiana, USA.
Ouwendyk
M
M
Francoeur
R
R
Pierratos
A
A
D000328:Adult; D000686:Amyloidosis / Q000097:blood / Q000209:etiology / Q000517:prevention & control; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000628:therapy; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis / Q000009:adverse effects / Q000379:methods*; D013997:Time Factors; D001613:beta 2-Microglobulin / Q000097:blood*
D001613:beta 2-Microglobulin