The “renal assist device” (RAD) is a bioartificial kidney — a device lined with human renal tubular cells grown from donated organs. Even with conventional dialysis, patients with acute kidney failure have a high mortality rate; the hope is that outcomes might be improved with the use of a bioengineered device which more closely replicates the functions of the human kidney. In the upcoming May issue of the Journal of the American Society of Nephrology, Dr. H. David Humes demonstrates that the use of the experimental RAD in patients with acute renal failure was associated with a decrease in the mortality rate of almost half and almost twice the rate of recovery of renal function:
"The cells are made available to carry out subtle metabolic and endocrine functions that the patient’s failing kidneys can no longer perform, thereby staunching a cascading decline in the patient’s health and allowing time for the patient’s own organs to recover," Dr. Humes explains.
Outcomes were significantly better for AKI patients treated with the RAD. After one month, 33 percent of patients in the RAD group had died, compared to 61 percent of those treated with renal replacement therapy only. Patients who received the RAD were also more likely to be alive after six months. With adjustment for other factors, the risk of death was about 50 percent lower in the RAD group.
Patients in the RAD group also had a shorter time to return of kidney function. Overall, kidney function recovered in 53 percent of patients with RAD, compared to 28 percent without RAD. In both groups, about 20 percent of patients survived but never recovered kidney function, requiring chronic dialysis.
Although the initial results are encouraging, the benefits of RAD treatment need to be confirmed in larger studies. In addition, the researchers need to study the effects of changes in the design of the RAD, which are needed to accommodate mass production.
