Beyond renal dialysis and transplantation – implantable artificial kidneys

Abstract

Chronic kidney disease constitutes a public health problem with increasing incidence, prevalence, poor outcomes and high cost. The awareness of and screening for chronic kidney disease remains low worldwide. Thus millions of people around the world suffer from kidney diseases, and these patients eventually will require a form of renal replacement therapy. Outcomes include kidney failure and complications of decreased kidney function with attendant cardiovascular diseases. Dialysis and transplantation, while effective, are not optimal therapies for kidney failure. This is a major reason why researchers have been working on better alternatives including growing 'new kidneys' and creating bioartificial kidney (Kidney Project), to treat end stage renal disease. The Kidney Project¹ is a US national research project with a goal to create a small, surgically implanted, bioartificial kidney to treat end stage renal disease (ESRD). The research team is headed by Shuvo Roy, PhD, a bioengineer in the University of California, San Francisco (UCSF), and co-directed by William Fissell, MD, at the Vanderbilt University Medical Center. The bioartificial kidney is expected to save lives and reduce drastically budget committed to renal replacement therapy. After more than 20 years of work, the clinical trials are scheduled to hold early 2018. Although kidney transplantation is still one of the best treatment options of ESRD, unfortunately there is shortage of organ donors that prevents transplants from being available to the vast majority of ESRD patients. Unlike transplants, the bioartificial kidney will not require that patients are on immunosuppressive drugs to prevent rejection².  It will be  powered by the body's own blood pressure, and does not require external tubes or tethers². Accordingly to the lead researcher,  'The implantable bioartificial kidney builds upon the existing extracorporeal Renal Assist Device (RAD), which is a bioartificial kidney that combines a membrane hemofilter and a bioreactor of human renal tubule cells to mimic many of the metabolic, endocrine, and immunological functions of a healthy kidney. While clinical trials confirmed that the RAD can safely treat acute renal failure in a critical care setting, adoption of the RAD for routine treatment of ESRD patients is hampered by its labor-intensive and complex operation, large size, and high marginal cost. The ultimate goal of The Kidney Project is to apply micro-electromechanical systems (MEMS) and nanotechnology to miniaturize the extracorporeal RAD into a surgically implantable, self-monitoring, and self-regulating bioartificial kidney.'