Kidney disease is a global issue. It relates to the general damage of the kidneys. Chronic kidney disease (CKD) is the most prevalent type, affecting 10% of the global population. While there is no specific cause, diabetes and high blood pressure can increase your risk of developing CKD. Kidney disease is separated into 5 stages. Stage 1 and 2 represent a risk for future kidney disease. Stage 3 represents mild to moderate CKD. Stage 4 is severe CKD, and stage 5 is full kidney failure. Approximately 2% of CKD patients reach stage 5 and require a kidney transplant or dialysis. Besides a transplant, dialysis is the current gold standard of treatment for patients with late-stage kidney disease. 90% of late-stage CKD patients undergo haemodialysis treatment. There are 2 types of dialysis:

• Haemodialysis (HD)
• Peritoneal dialysis (PD).

Dialysis is a ex vivo treatment, meaning it takes place outside the body. Haemodialysis works by taking the blood outside the body and passing it through a machine to clean it. This process typically takes 3-5 hours to complete and requires 3-4 visits to the hospital a week. This can be very mentally strenuous on the patient, taking between 9-20 hours out of the week. Peritoneal dialysis is a newer option that involves pumping solvent into the abdominal cavity and allowing the body to diffuse waste out before removing the solvent. The below video explains these principles.

Artificial Kidneys

What is an artificial kidney?

Some may consider dialysis to a be an artificial kidney. The Kidney Project’s artificial kidney is an implantable biomedical device that will work like a natural kidney and provide 24/7 treatment. While the team’s aim is to fully replicate kidney function. Promising strides have been made with current prototypes replicating kidney function on the same level as stage 3-4 CKD.

How does it work?

Artificial kidney technology has made lots of progress through the years. First attempts included the work of Willem Kolff where they design a device that weighed 3.5kg but needed to be periodically connected to 20L of fluid. More recently many devices using peritoneal dialysis as its main starting point. The Kidney Project’s artificial kidney has introduced a new element, a bioreactor. In addition to the haemofilter these two components work together to clean and process the blood. Dr Shuvo Roy, one of the collaborators in the Kidney Project said, “The hemofilter processes incoming blood. It creates “ultrafiltrate”, a solution containing dissolved toxins, sugars, and salts. The bioreactor contains kidney cells. It processes the ultrafiltrate and directs wastes and excess fluid to the bladder for removal.” The device requires no external power source or connections, it uses the blood pressure of the body to power the device and run the blood through it. “The pores are big enough to allow waste and excess fluids into the bioreactor but small enough to keep out immune cells,” Dr Roy said. “This allows the artificial to work while remaining isolated from the immune system.” A video below explains the principle of the artificial kidney.

Conclusion

Dialysis has been the gold standard for many years now but the downsides still remain. It takes away so much time from the patient such that a fulfilling life is often not a possibility. With the additional use of biotechnology, could implantable technology be the way forward?

References

• Oladimeji Ewumi (2025). Kidney Disease Burden Is Bigger Than You Think, and Growing. [online] MedCentral. Available at: https://www.medcentral.com/nephrology/kidney/kidney-disease-burden-is-bigger-than-you-think-and-growing

• Suriyong, P., Ruengorn, C., Shayakul, C., Anantachoti, P. and Kanjanarat, P. (2022). Prevalence of chronic kidney disease stages 3–5 in low- and middle-income countries in Asia: A systematic review and meta-analysis. PLOS ONE, 17(2), p.e0264393. doi:https://doi.org/10.1371/journal.pone.0264393.

• Kidney Care UK. (n.d.). Stages of chronic kidney disease (CKD). [online] Available at: https://kidneycareuk.org/kidney-disease-information/stages-of-kidney-disease/stages-of-chronic-kidney-disease-ckd/.

• Cherney, K. (2025). What Is the Mortality Rate of Renal (Kidney) Failure? [online] Healthline. Available at: https://www.healthline.com/health/kidney-disease/renal-failure-death-rate#mortality-rate

• lauren.hoskin@nihr.ac.uk (2024). Dialysis for kidney failure: evidence to improve care. [online] NIHR Evidence. Available at: https://evidence.nihr.ac.uk/collection/dialysis-for-kidney-failure-evidence-to-improve-care/.

• Karageorgos, F.F., Stavros Neiros, Konstantina-Eleni Karakasi, Vasileiadou, S., Katsanos, G., Antoniadis, N. and Georgios Tsoulfas (2024). Artificial kidney: Challenges and opportunities. World journal of transplantation, [online] 14(1). doi:https://doi.org/10.5500/wjt.v14.i1.89025.

• National Kidney Foundation (2024). The Future of Artificial Kidneys. [online] Kidney.org. Available at: https://www.kidney.org/news-stories/future-artificial-kidneys.

• Ucsf.edu. (2019). Home | The Kidney Project | UCSF. [online] Available at: https://pharm.ucsf.edu/kidney.