Kidney donation: age limit, compatibility, tests to be done

Kidney failure is an increasing pathology in France. It goes hand in hand with the increase in kidney disease which may be due to diabetes, high blood pressure or a congenital disease. Kidney transplantation is one of the possible treatments. Several questions then arise: who can donate a kidney? How does this intervention take place? What are the consequences for the donor?

Who can donate a kidney?

Kidney donation is possible in France for all living and healthy adult adultsthat is to say the parents and the whole family of a patient: mother, father, brothers and/or sisters, spouses, cousins, cousins… : “In fact, kidney donation has been extended to anyone providing proof of a friendly relationship of at least two years with the recipient. Thus, many people can be potential donors“, adds Pr Christophe Legendre, nephrologist. Over the year 2022, there were 170 transplants at Necker Hospital including 40 transplants from living donors. “This year is not very representative because of the post-Covid period, we are generally around 60 transplants from living donors“, he notes.

What are the contraindications to kidney donation?

There are several contraindications to kidney donation:
► the main one is a HLA incompatibility problem (genetic map of each individual) : “the medical team will ensure that the recipient has not developed antibodies directed against the donor, which would prevent the transplant“.
► a insufficient kidney function to be split in two:the older the donor (generally, parents who are between 70-75 years old), the more this situation can arise. We cannot be sure in this case that by removing one kidney, the second can take over. This is a potential risk for the donor“;
► a chronic disease such as diabetes
► or the discovery of cancer.
Today, compatibility between ABO blood groups is no longer mandatory: “incompatible ABO grafts can be performed. We must have the same attitude for kidney donations as for blood donations. We indeed have the means to remove the antibodies which are embarrassing for the realization of the transplantation “says Professor Legendre.

What are the tests to do to donate a kidney?

The candidate for kidney donation will be the subject of a complete medical check-up with clinical, radiological and biological examinations to ensure the compatibility between the donor and the recipient, and the good health of the donor kidney. The balance sheet will include blood tests for compatibility. Kidney function will also be measured in a day hospital. “We will also check if it does not exist heart abnormalities by ultrasound of the heart“. In order for surgeons to see the conformation of arteries and veins, an abdomino-pelvic CT scan with product injection contrast will also be performed to obtain good quality imaging. aspect of kidney function.

Do you have to be compatible with the receiver?

“The best is to be compatible, that’s why giving within families is encouraged, since the father and the mother give half of their genes to their children, so the HLA profiles can be identical and the risk of transplant rejection is very, very low“, insists Professor Legendre. The family circle is therefore highly compatible for the donation of a kidney. Compatibility is important but we also try to avoid incompatibility. looking at antibodies and the possibility of removing them and to make transplantation possible. “In summary, the gift is made within the family with the compatible pair and outside the family with the pair that is not incompatible.

Can you donate a kidney if you have smoked?

Smoking is not a contraindication to kidney donation, it is rather its impact. “We try to make people aware of quitting smoking, but as long as smoking has not induced lung damage and vascular damagedonation may be possible“, he underlines.

What is the age limit for donating a kidney?

Age limit is relative to aging kidney function and the risk that the donation may cause. “There are not enough data to confirm the risks associated with this type of intervention for a 75-year-old patient who donated a kidney whether it is to have a heart attack or to die afterwards”.

Kidney donation is paid for by the hospital

The donor’s journey is punctuated by steps: information on risks and consequences any sample issued by the medical-surgical team, the expression of his consent before a magistrate and the summons of the donor by the living donor committee which authorizes or not the removal. Once the exams are correct and the requirements met, the intervention is carried out by laparoscopy and consists of removing one of the two kidneys. The surgeon will introduce the instruments and a camera into the abdomen through pipes. A gas is then insufflated so that the various organs of the abdominal cavity separate from each other to remove whatever is holding the kidney in the retroperitoneum. The kidney thus separated from the other organs will be slid along the side inside the abdomen to emerge through a small scar (8-10 cm) located above the fold of the groin. In a few cases, the kidney will come out through the umbilicus or through the vagina.

What are the consequences of kidney donation for the donor?

The short-term consequences, after the intervention, are the pain that will be taken care of because of the surgical procedure and fatigue for 1-1.5 months. There phlebitis is also a post-operative risk which will be controlled throughout the hospitalization (which lasts 7 days). The donor will keep only one kidney and it will grow a little to take up the available space. The donor will be able to live in the same way as before the donation of his kidney: “the donor, who is not sick, will regain the shape he had before the intervention and overall, there is no treatment, diet, prohibitions. He’ll just have one more scar“, he adds. In France, there is a national register of living donors which ensures follow-up: “Every year, on the “anniversary” date of the nephrectomy, a prescription is sent to the donor for blood and urine tests to check that their kidney is working. His blood pressure is also checked, in order to treat it if ever it was not normal“.

Is it free to donate your kidney? What cost if not?

Kidney donation is covered by the hospital where the operation is performed. The medical cost of a kidney transplant in France would amount to 80,000 euros the year of the transplant, then 20,000 euros per year. To these costs are added those of the steps prior to transplantation, in particular the search for a donor, the removal of the organ, or even the management of the national waiting list. A study published in 2014 in Nephrology & Therapeutics shows that the amounts invoiced in addition to the transplant rise from 13,835.44 to 20,050.67 euros for a deceased donor and 13,601.66 euros for a living donor.

Thanks to Pr Christophe Legendre, nephrologist at the Adult Nephrology-Kidney Transplantation Department, Necker-Enfants Malades Hospital, Paris.