beta(2)-Microglobulin and Phosphate Clearances Using a Wearable Artificial Kidney: A Pilot Study

Background: Additional small-solute clearances during standard thrice-weekly hemodialysis treatments have not improved patient survival. However, these treatments have limited middle-molecule clearances. Thus, newer therapies designed to increase middle-molecule clearances need to be developed and evaluated. Study Design: Pilot clinical trial to measure beta(2)-Microglobulin and phosphate clearances with a wearable hemodialysis device. Setting & Participants: 8 regular hemodialysis patients under the care of a university teaching hospital. Intervention: Patients were fitted with a wearable hemodialysis device for 4 to 8 hours. Outcomes: All patients tolerated the treatment. Results: Average amount of beta(2)-microglobulin removed was 99.8 +/- 63.1 mg, with mean clearance of 11.3 +/- 2.3 mL/min, and an average of 445.2 +/- 326 mg of phosphate was removed, with mean plasma phosphate clearance of 21.7 +/- 4.5 mL/min. These clearances compared favorably with mean urea and creatinine plasma clearances (21.8 +/- 1.6 and 20.0 +/- 0.8 mL/min, respectively). Limitations: Proof-of-concept preliminary trial. Additional studies are warranted to confirm these positive preliminary data. Conclusions: This wearable artificial kidney potentially provides effective beta(2)-microglobulin and phosphate clearances and, by analogy, middle-molecule clearances. Am J Kidney Dis 54:104-111. (c) 2009 by the National Kidney Foundation, Inc.