Technological Advances in Renal Replacement Therapy

Abstract

The worldwide epidemic of chronic kidney disease shows no signs of abating in the near future. Current dialysis forms of renal replacement therapy (RRT), even though successful in sustaining life and improving quality of life somewhat for patients with ESRD, have many limitations that result in still unacceptably high morbidity and mortality. Transplantation is an excellent option but is limited by the scarcity of organs. An ideal form of RRT would mimic the functions of natural kidneys and be transparent to the patient, as well as affordable to society. Recent advances in technology, although generally in early stages of development, might achieve these goals. The application of nanotechnology, microfluidics, bioreactors with kidney cells, and miniaturized sorbent systems to regenerate dialysate makes clinical reality seem closer than ever before. Finally, stem cells hold much promise, both for kidney disease and as a source of tissues and organs. In summary, nephrology is at an exciting crossroad with the application of innovative and novel technologies to RRT that hold considerable promise for the near future.Clin J Am Soc Nephrol 4: S132-S136, 2009. doi: 10.2215/CJN.02860409 T he ongoing worldwide epidemic of chronic kidney disease (CKD) includes ESRD. According to recent US Renal Data System estimates, more than 900,000 patients worldwide have ESRD and are on renal replacement therapy (RRT) (1). The majority of these patients are on intermittent, diffusion-based hemodialysis (HD), with only a relatively small fraction able to receive kidney transplants because of the scarcity of available donor organs.Even though dialysis is touted as the only currently available successful therapy that replaces the functions of an organ ex vivo, it has several limitations. The advent of clinical dialysis in the 1950s has had a huge impact on the way in which ESRD and acute kidney failure are managed, but several decades later, the morbidity and mortality in patients with ESRD remain unacceptably high (1). One possible reason is that the equivalent clearance provided by three-times-a-week conventional HD or typical continuous ambulatory peritoneal dialysis (PD) is barely 15 to 20 ml/min, and the treatment by any criterion is unphysiologic (2). At the same time, the quality of life of patients who are on dialysis has remained suboptimal, and the cost of these procedures has remained high.Several attempts have been made to prove intramuscularly the efficiency of dialysis and outcomes in patients. In HD, these attempts include more biocompatible membranes, high-flux and high-efficiency membranes, more frequent and longer duration of dialysis, use of convective forms of therapy, and use of more user-friendly delivery systems. In PD, introduction of automated cyclers has improved convenience of the technique for some patients, increased the practical volume of dialysate, and, therefore, increased solute clearance and ultrafiltration capacity; however, none of these advances has had a substantial impact on patient outcomes.An ide...

Morphological Characterization of the Polyflux 210H Hemodialysis Filter Pores

“…Current data on membrane morphology [1] and patient morbidity and mortality [2] support the need to improve membrane design to better increase the clearance of uremic toxins, particularly the middle molecules [3–8]. As such, more relevant information on current membrane properties and their potential limitations is essential.…”

The Evolving Ethics of Dialysis in the United States

“…Options beyond treatment at a center three times weekly, such as home peritoneal dialysis or short daily or long nocturnal hemodialysis, can now be offered to appropriate patients (26). The future promises even more dramatic innovation (34). As these options differ greatly in their effect on daily life, the choice should be based largely on patient-specific values, which may include preservation of independence, amount of time spent on dialysis, need to travel, impact on family, and ability to continue important activities (35).…”

Renal Regeneration

“…Renal transplantation is still considered the option of choice for the treatment of most ESRD patients. However, only a small percentage of these patients are recipients of organ transplantation due to the limited number of organ donors [3]. Moreover, frequent complications with immunosuppressive drugs underscore the need for possibly better alternative therapies for ESRD patients.…”