β2-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 β 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 β 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 β 2 -microglobulin and phosphate clearances and, by analogy, middle-molecule clearances.