Krieter Detlef H, Falkenhain Sven, Chalabi Lotfi, Collins Gregory, Lemke Horst-Dieter, Canaud Bernard
Department of Nephrology, University of Montpellier, and U.D.S.A.-A.I.D.E.R., Clinique Jaques Mirouze, Montpellier, France.
Kidney Int. 2005 Jan;67(1):349-56. doi: 10.1111/j.1523-1755.2005.00088.x.
Several studies have indicated that the improved elimination of middle molecules by convective renal replacement procedures might be associated with a better outcome in end-stage renal disease (ESRD). On-line mid-dilution hemodiafiltration (HDF) with the Nephros OLpur MD 190 hemodiafilter represents a novel extracorporeal renal replacement therapy concept to increase the removal of middle molecules.
In a prospective cross-over study in 10 ESRD patients, this technique was compared to on-line post-dilution HDF with a conventional synthetic high-flux dialyzer, operated at its technical limit, concerning small and middle molecular solute removal. Each patient was treated 3 times for 4.0 +/- 0.4 hours with both filters. Blood flow was 400 mL/min, substitution flow (Q(S)) during mid-dilution HDF 200 mL/min, and during post-dilution HDF 100 mL/min, and effective dialysate flow of 700 - Q(S) mL/min. Instantaneous clearances, reduction ratios (RR), and middle molecule mass transfer in continuously collected dialysate were determined.
While urea and creatinine clearances were significantly lower (6.4% and 3.9%, respectively), middle molecule removal was much more efficient in mid-dilution HDF over the whole range of investigated proteins: compared to post-dilution HDF, beta(2)-microglobulin (11.8 kD) clearance (165.8 +/- 26.59 vs. 201.9 +/- 20.63 mL/min; P < 0.001), RR (80.0 +/- 5.4% vs. 82.2 +/- 5.7%; P < 0.001), and dialysate mass transfer (53% higher; P < 0.001) were significantly higher. For the larger middle molecules, cystatin C (13.4 kD) and retinol-binding protein (21.2 kD), mid-dilution HDF resulted in an even more superior performance, indicated by significantly higher values of all investigated parameters.
On-line mid-dilution HDF with the Nephros OLpur MD 190 hemodiafilter appears to be a true technologic step ahead in terms of improved middle molecule removal. This efficient procedure gives hope to play a role in preventing or at least retarding dialysis-related long-term complications, such as beta(2)m amyloidosis, in ESRD patients, and may contribute to a more adequate dialysis therapy.
多项研究表明，通过对流性肾脏替代程序更好地清除中分子物质可能与终末期肾病（ESRD）的更好预后相关。使用Nephros OLpur MD 190血液透析滤过器进行在线中稀释血液透析滤过（HDF）代表了一种新型的体外肾脏替代治疗概念，以增加中分子物质的清除。
在一项针对10例ESRD患者的前瞻性交叉研究中，将该技术与使用传统合成高通量透析器、在技术极限下运行的在线后稀释HDF进行了比较，比较了小分子和中分子溶质的清除情况。每个患者使用两种滤器各治疗3次，每次4.0±0.4小时。血流速度为400 mL/分钟，中稀释HDF期间的置换流速（Q(S)）为200 mL/分钟，后稀释HDF期间为100 mL/分钟，有效透析液流速为700 - Q(S) mL/分钟。测定即时清除率、降低率（RR）以及连续收集的透析液中的中分子物质质量传递。
虽然尿素和肌酐清除率显著较低（分别为6.4%和3.9%）但在整个研究蛋白质范围内，中稀释HDF的中分子物质清除效率更高：与后稀释HDF相比，β2-微球蛋白（11.8 kD）清除率（165.8±26.59对201.9±20.63 mL/分钟；P<0.001）、RR（80.0±5.4%对82.2±5.7%；P<0.001）以及透析液质量传递（高53%；P<0.001）均显著更高。对于更大的中分子物质，胱抑素C（13.4 kD）和视黄醇结合蛋白（21.2 kD），中稀释HDF的性能更优，所有研究参数的值均显著更高表明了这一点。
使用Nephros OLpur MD 190血液透析滤过器的在线中稀释HDF在改善中分子物质清除方面似乎是一个真正的技术进步。这种有效程序有望在预防或至少延缓ESRD患者透析相关的长期并发症（如β2m淀粉样变性）方面发挥作用，并可能有助于实现更充分的透析治疗。
