By: Kumba Seddu, Sophie Suechting, Blake McCartney
http://youtu.be/bgJ-zw1P40Y
As of June 21, 2013 96,645 people in the United States await kidney transplants. Last year, 4,903 patients died while awaiting a kidney transplant. These patients suffer from very advanced chronic kidney disease, which requires dialysis or a kidney transplant to maintain life. The two main causes of chronic kidney disease are diabetes and high blood pressure, which are responsible for up to two-thirds of the cases.
Experimentation with renal transplantation started in humans around 1906. There were many failed attempts using kidneys (and other organs) from animals; this method resulted in tissue rejection and was ultimately fatal. In 1954 Murray performed the first successful transplant with a donor on the identical Herrick twins – the kidney started producing urine immediately. Shortly after, in 1960, Murray performed another successful transplant on twelve year-old twins Johanna and Lana Nightingale. Murray was unable to perform advanced tissue and blood typing, but the transplants worked because the twins were an exact match. Later, advancements for non-twin donor pairs developed. Research also continued in the field of immunology, improving transplantation success rates and decreasing cases of tissue rejection.
Dr. Murray (left) and the Herrick twins.
Dr. Murray (center) and the Nightengale twins.
The kidneys are located in the back of the abdominal cavity in the retroperitoneum. Their function is to filter blood and remove waste from the body. If the kidneys are unable to adequately filter waste products from the blood, the body can enter renal failure. Renal failure requires regular dialysis or a kidney transplant to maintain proper bodily functions.
Scientists have always been fascinated with discovering a way to preserve organs for transplantation. It was discovered that there is a reversible effect of hypothermia on the metabolic processes of isolated tissues and that when the tissues are rewarmed their function returns to normal. There are currently two main methods of organ preservation that both freeze the tissues: machine perfusion and simple cold storage. Machine perfusion was researched first as it seemed to most effectively mimic the actual physiology of the organ. Cold storage was discovered soon after and became the primary method of organ storage due to its simplicity, quality of organ preservation, and cost effectiveness. There still remains a debate today as to which preservation method is best, but cold storage continues to be the method of choice due to its simplicity and a lack of clinical evidence advocating for machine perfusion instead.
Due to the increased rate of surgical morbidities, the diseased kidney is usually left in its position. The transplanted kidney is placed in a different position, usually the iliac fossa, using a different blood supply. The renal artery of the kidney, branching from the donor’s abdominal aorta is connected to the recipient’s external iliac artery. The renal vein initially connected to the donor’s inferior vena cava is joined to the recipient’s external iliac vein.
The optimization of the Paired Donor Schema helps to increase the degree of compatibility in recipient and donor antigens. Blood test, Tissue test and cross matching are done on both recipient and donor and the results are then computed into an algorithm from graph theory. A random permutation is done and compatible matches are identified. This reduces rejection and helps better the transplant procedure.
Sources:
“About Chronic Kidney Disease.” The National Kidney Foundation: Kidney Disease. N.p., n.d.
Web. 14 Jan. 2014. <http://www.kidney.org/kidneydisease/aboutckd.cfm>.
Moers, Cyril, Jacques Pirenne, Andreas Paul, and Rutger J. Ploeg. “Machine Perfusion or Cold
Storage in Deceased-Donor Kidney Transplantation.” The New England Journal of Medicine (2012): n. pag. Web. 15 Jan. 2014.
Petechuck, David. “Organ Transplantation .” Google Books. N.p., n.d. Web. 15 Jan. 2014.
<http://books.google.com/books?id=POQB4YIjAnoC>.
Smith, Rebecca. “Breakthrough in Kidney Transplant ‘could Cut Waiting List'” The Telegraph.
Telegraph Media Group, 30 June 2008. Web. 15 Jan. 2014.
Smith, Susan. “Immunologic Aspect of Organ Transplant.” Medscape Log In. N.p., n.d. Web. 15
Jan. 2014. <http://www.medscape.com/viewarticle/436533_11>.
Terasaki, Connolly, and Jeffrey L. Veale “The New England Journal of Medicine.” Kidney Paired
Donation. N.p., n.d. Web. 15 Jan. 2014. <http://www.nejm.org/doi/full/10.1056/NEJMc1106996>.